Untitled

[juniperpublishers-nutrition]

Nutrition And HIV/AIDS: A Qualitative Study on Perceived Factors Affecting Feeding Practices among Adult People Living with HIV/AIDS in Kigali, Rwanda

Abstract

Background: A bidirectional relationship exists between nutrition and HIV/AIDS. Poor nutrition has been associated with unsuppressed viral loads among People Living with HIV/AIDS (PLWH) while HIV infection leads to poor nutrition. HIV treatment, care and support efforts should thus incorporate nutrition management. Despite the fact that various scholars have researched the dietary status of PLWH, there is paucity of explorative research exploring factors that drive feeding practice among adult PLWH. This study therefore aimed to explore the perceptions of PLWH on factors that affect their feeding practices and ultimately dietary diversity.

Methods: Three health facilities were purposively selected as study sites. Interviews were conducted by a trained health professional in a private room at the study sites. Participants were purposively selected for enrolment. Only participants who had recorded a low body mass index (<18.5) were considered for the interview prior to provision of nutrition related routine health education. Sample size was controlled by saturation of information. A pre-tested interview guide was used. The interview guide was developed based on guidelines from WHO and Rwanda National Guidelines for Comprehensive Care of People Living With HIV/AIDS. The conventional content analysis approach was used for the analysis of data.

Results: There were three major themes that emerged from data analysis: knowledge on importance of good nutrition in HIV/AIDS, food availability and, habits and family preferences that affect food intake. The feeding habits of the respondents were guided by their nutritional knowledge, availability of food and also by their habits and family preferences.

Conclusion: There is need for improved health education for PLWH on nutrition challenges associated with HIV/AIDS. The study further underscores the need for nutrition messages that extend to address habitual and family preferences.

Keywords: People living with HIV/AIDS; Nutrition; HIV/AIDS

Abbrevations: PLWH: People Living with HIV

Introduction

In 2016, the United National General Assembly set an ambitious goal to end AIDS epidemic by 2030 [1]. This call has seen many countries, including Rwanda, scaling up interventions that aim to scale up HIV diagnosis, antiretroviral therapy (ART) initiation and care continuum [2]. Not surprisingly, Rwanda has been one of the first countries reported to have reached The Joint United Nations Programme on HIV/AIDS (UNAIDS) 90-90-90 targets [3]. Despite this remarkable progress, UNAIDS, in 2017, there were 940,000 AIDS related deaths globally [4]. With ART coverage well established in most HIV struck regions, HIV researchers have attributed this mortality to the little focus on nutrition related care for people living with HIV/AIDS (PLWH) [5,6].

A bidirectional relationship exists between nutrition and HIV/AIDS [7-9]. Poor nutrition has been associated with unsuppressed viral loads among PLWH [10], while HIV infectionleads to poor nutrition [11,12]. HIV treatment, care and support efforts should thus incorporate nutrition management. As such, global interest in the concept of improving health outcomes for PLWH through proper nutrition has seen a multiorganizational effort including The U.S. President’s Emergency Plan for AIDS Relief (PEPFAR), WHO, UNAIDS, and the World Food Program (WFP) [13]. As of 2016, UNAIDS reported the heaviest burden of malnutrition to be in sub-Saharan Africa [14]. Studies measuring impact of malnutrition among PLWH have reported prevalence over 20% [8,15]. Such high prevalence is worrisome as poor dietary diversity has been associated with greater morbidity and mortality among PLWH [16,17].

While dietary status of PLWH has been researched elsewhere [18-21] there is paucity of explorative research exploring factors that drive feeding practice among adult PLWH. The purpose of the current study was to explore perceptions of PLWH on factors that affect their feeding practices and ultimately dietary diversity.

Methods

Study setting, sampling and participant enrolment

Three health facilities were purposively selected as study sites. Interviews were conducted by a trained health professional in a private room at the study sites. Participants were purposively selected for enrolment. Only participants who had recorded a low body mass index (<18.5) were considered for the interview prior to provision of nutrition related routine health education. Sample size was controlled by saturation of information [22].

Ethical considerations

Ethical approval was obtained from University Teaching Hospital of Kigali Ethics Committee (Approval number: EC/ CHUK/0129/2019). All participants signed informed consent prior to being interviewed.

Data collection and analysis

We used a pre-tested interview guide to collect data. The interview guide was developed based on guidelines from WHO [23] and Rwanda National Guidelines for Comprehensive Care of People Living With HIV/AIDS [24]. A survey trained interviewer, GP, conducted the interviews in a private room at the study site. We followed the steps; verbatim transcription, translation, back translation, upload of translated script into NVivo version 12, and reading, coding and narrative presentation of findings. We followed the conventional content analysis approach in analyzing data [25]. With this approach; themes were derived directly from the text data [25].

Results

A total of 15 PLWH were recruited. Out of this total, 7 were recruited from University Teaching Hospital of Kigali, 5 fromKibagabaga Hospital and 3 from Rwanda Military Hospital. Participants were aged between 29 and 52 years. More information on the informants is available on Table 1.

Knowledge on importance of good nutrition for PLWH

Majority of the interviewees demonstrated good knowledge of the importance on nutrition for PLWH. Counselling sessions at time of ART collection was the most cited source of information. ‘‘I know, because we have some food which are important in building our body, for energy and other which protect our body being attacked with some diseases’’ Source: PLH3‘‘…for us because of ARVs we need to eat well and even sufficiently. So that you live long, because to take it [ART] without sufficient food intake it not good as well. So we eat the food that contains all nutritive value like meat, milk, eggs, beans, porridge and others’’ Source: PLWH1

Food availability

Theme two revealed a major barrier was food availability. Interviewees expressed cost as a major factor influencing food availability. Some respondents could only afford certain types of food at certain times of the year where they would be plenty and relatively affordable. Meat was discussed as the most challenging food to obtain for most participants. ‘‘… I tested positive in 2003. At the time, I was living with my family nearby this health facility. There was not treatment that time but later that is when I started collecting have started my treatment in this facility, then as time goes on, this area become very expensive, and I couldn’t be afford to stay around here that why I shifted to Kagugu. So, if to live [rentals] are expensive, it also affects food….’’ Source: PLWH 2‘‘…sadly myhusband passed away, current I am living together with my child, as I said I am not working, therefore to have food is very difficult for us, and end results ARVs affect me in negative way….’’ Source: PLWH4

Habits and family preferences

From theme three, participants described how some habits and family preferences affected their feeding practice. Some participants found it difficult to change their feeding routine to incorporate some foods they normally would not take before being diagnosed with HIV. On the other hand, some participants felt their feeding practice was dependent on their family preferences as they would normally find it hard to have two sets of meals prepared; with one to accommodate their needs. “....my wife has diabetes, so we take different food. I mean she prepares the food different from what I need [as an individual living with HIV/AIDS].” Source: PLWH5“…even before I started taking these pills [ART], fruits were a luxury. I cannot afford to buy fruits so I can consume every day. You can imagine paying 400 Rwandan Francs for one orange. Better I buy one kilogram of Irish potatoes with that money.” Source: PLWH7

Discussion

The main aim of this study was to explore the perceived factors affecting feeding practices among adult people living with HIV/AIDS in Kigali, Rwanda. Based on the findings of the study, there were three main themes emerged. Most participants had good knowledge on importance of good nutrition in HIV/AIDS or were at least aware of the need for good nutrition when living with HIV/AIDS. Food availability and, habits and family preferences emerged as major factors participants perceived affected their feeding practices. These findings underscore the urgent need for renewed focus on nutrition as one of the main components of a comprehensive package of care for individuals who are living with HIV/AIDS [5,6].

Knowledge on importance of good nutrition for PLWH

Based on the findings of the current study, participants demonstrated good knowledge on importance of proper nutrition for PLWH. Counseling sessions at time of ART collection was the most cited source of information. The findings of this study corroborate well with the findings of Anand & Puri [26], which noted that PLWH possessed knowledge concerning nutrition. However, the study noted that most of them did not score very high when it comes to the practices section.

The study noted that while the individuals had proper nutritional knowledge, they did not apply them in their daily practices. The findings of a descriptive study, which was done by Young et al. [27] on nutrition-related knowledge, attitude, and practices (KAP) among individuals who live with HIV/AIDS (PLHIV) in India, demonstrated that while the attitude toward the disease and food was positive, the use of nutritional knowledge was lacking. The findings of the study by Young et al. [27] further noted that the PLWH were having proper knowledge regarding the significance of nutrition during infection.

At the same time, it noted that PLWH had a positive attitude toward the disease as well as the significance of nutrition during the course of the disease. The study further noted that translation of the knowledge into practice was generally low. Therefore, the scholars recommended continuous interventions, which are mainly aimed at behavior change to ensure conversion of the knowledge into healthy dietary practices [27].

This finding points out that knowledge on importance of good nutrition for PLWH is one of the perceived factors, which affects the feeding practices among adult PLWH in Kigali, Rwanda. Good nutritional information for the PLWH plays a key role in improving the overall quality of life of individuals through the provision of the nutrients, which are needed by the body. Besides, it is highly beneficial in keeping individuals’ immune system stronger in such a manner that they are capable of fighting diseases. In addition, through the nutritional information, they are in a position to manage HIV symptoms and complications effectively.

As a result, the government of Rwanda through the relevant authorities should ensure that measures are put in place to ensure that PLWH have access to highly credible nutritional information as it is one of the main perceived factors, which affects the feeding practices among adult people living with HIV/AIDS. Greater financial, political, and technical support ought to be provided to ensure that there are improvements in the quality of nutritional information that is conveyed to PLWH.

Nutrition counseling is a key strategy, which can be used by the government of Rwanda in order to disseminate nutritional information. The relevant authorities can ensure that there is adequate allocation of resources to ensure nutritional counseling it carried out in the right manner. Besides, the healthcare providers should enhance nutrition education to PLWH.

Food availability

From participant responses, an important factor, which affects the feeding practices among adult PLWH in Kigali, is food availability. The findings of the study noted that lack of food is one of the main challenges, which hamper the fight against HIV. Based on the findings of the study, a major concern regarding availability of food was the cost, which is associated with food. The high costs, which are associated with some of the foods hinders some of the PLWH from accessing them. As a result of the costs, affordability of some kinds of foods is notpossible. The findings of the study revealed that meat was the most challenging food to obtain.

The finding of the study is similar to the findings of other studies, which have been carried out by previous scholars. The findings of a number of other studies corroborates well with the findings of the current study. For instance, studies carried out in Mali [28,29], Taiwan [30], Vietnam [31], France [32] and Uganda [33] also concluded that food availability and access is a key factor, which influences the feeding patters of PLWH. The findings of the study noted that lack of some kinds of foods result in poor dietary practices. A separate study that was done by Young et al. [27] noted that food insecurity is one of the key barriers to adherence to care among PLWH.

Similarly, a study, which was carried out by Weiser et al. [34] also noted that there is an inextricably link between food insecurity and the HIV epidemic. Rodas-Moya [35] also carried out a study on the preferences for food and nutritional supplements among adult PLWH in Malawi. The findings of the study illustrated that food insecurity might contribute to intra-household sharing of various nutritional supplements.

Based on the findings of the study, it can clearly be pointed out that food availability affects the feeding practices among adult people living with HIV/AIDS in Kigali, Rwanda.

As a result, the government and the other relevant authorities ought to ensure that there are different kinds of measures in place to ensure that the challenge of food availability is looked into. One of the main measures, which can be put in place, is the development of various national level strategies, which can ensure that food, assistance as well as nutritional support are integrated into the national strategic plan. In addition, the government ought to ensure that the partners, who are involved in food assistance at the community levels, national levels as well as at international levels, are identified.

They can also ensure that a criteria in which foodassistance is offered is properly defined. The government should also define the standards of nutritional support to be provided to the pregnant women, nursing mothers as well as young children with the aim of ensuring prevention of mother to child transmission. The government should also be involved during the development of national policy to guide the community-based organizations, which are willing to offer nutritional support.

The government also needs to ensure that the healthcare facilities are well equipped with the human resources, infrastructure, as well as the supplies, which are needed. Incorporation of nutritional support into HIV/AIDS care always need workers to ensure distribution of adequate food assistance to community-based organizations, clinics, hospitals and schools among others. The government can alsoensure that there are adequate resources to ensure effective transportation of various food supplies and that there is proper storage for the given supplies

Habits and family preferences

Participants highlighted personal habits and family preferences as important factors that affect the feeding practice of PLWH. Based on the findings of the study, a number of the respondents indicated that as a result of HIV, they changed their feeding routine in order to include even foods, which previously they were not taking before being diagnosed with HIV. In addition, there were participants who opined that their feeding practice depended on the preferences of their families.

For instance, some of them previously found it very hard to have two sets of meals prepared; with one to accommodate their needs. The findings of a study that was done by Maertens [36] also noted that one of the main barriers to nutrition management among PLWH is family and personal preference. Based on the findings of the study, most of the patients noted that their attitudes toward changing their diet was brought about by being HIV-positive. At the same time, a number of the participants noted that their preferences for less healthy foods, together with the needs and preferences of their families made management of nutrition to be more challenging on a daily basis. This is similar to the findings of the study, which was carried out by Young et al. [27].

The study therefore notes that the preferences of PLWH for less healthy foods together with their families’ needs and preferences make the management of nutrition to be highly challenging. Measures needs to be put into place to ensure that PLWH are trained on specific nutrition management techniques like shopping, cooking and how they can balance food with illness. The government should also be involved during the development of national policy to guide the community-based organizations, which are willing to offer nutritional support

Conclusion

In PLWH, good nutrition plays a major role in supporting the overall health besides helping to maintain the immune system. At the same time, good nutrition is also highly beneficial for PLWH to maintain a healthy weight. As a result, HIV treatment, care and support efforts should thus incorporate nutrition management. This was a qualitative study based on the perceived factors affecting feeding practices among adult people living with HIV/AIDS in Kigali, Rwanda. It can be concluded that knowledge on the importance of good nutrition in HIV/AIDS, food availability as well as habits and family preferences are some of the main The study concludes that the major perceived factors, which affects feeding practices among adult people living with HIV/AIDS in Kigali, Rwanda include: knowledge on importance of good nutrition in HIV/AIDS, food availability and, habits and family preferences that affect food intake. As a result, the relevant authorities should ensure that there are measures in place aimed at ensuring provision of the right information to the PLWH. PLWH should also get information on how they can balance their food habits and preferences with the illness. The government should also be involved during the development of national policy to guide the community-based organizations, which are willing to offer nutritional support.

To Know More About Nutrition and Food Science International Journal 

Please click on: https://juniperpublishers.com/nfsij/index.php

For more Open Access Journals in Juniper Publishers

please click on: https://juniperpublishers.com/index.php

[juniperpublishers-nutrition]

Obesity in Obstetrics

Mini review

The people in industrialized countries have experienced a dramatic increase in obesity in recent times. Prevalence of obesity has doubled in the last 25 years. In the United States, 17-th on the list of most obese places in the world - average BMI 28.8 Kg/m2, more than 60% of reproductive-age women are overweight and 35% are obese, representing a 70% increase in pre-pregnancy obesity. In Romania, 75th on the list- average BMI is 22.2 Kg/m2, the lowest average BMI in the European Union (9.4% obesity in 2016). [1] One of three Romanians is overweight, and one of four is obese. There are over 3.5 million obese in Romania. The highest obesity rate is recorded in Moldova, where the percentage is 23.8%. Only 10% of them see a doctor. Only one percent are included in a national obesity education program [2].

Not all ethnic groups are at equal risk. Of particular concern is the rapid increase in adolescent overweight and obesity. Concordantly, pregnancy obesity rates are also increasing. Obesity is associated with increased morbidity and 6- to 12-fold increase in mortality. Obesity is highly complex in terms of etiology and prevalence. Genetic predisposition, race, socioeconomic status, built environment (e.g., the presence of sidewalks or community design), accessibility of healthy and affordable foods, sleep habits, and geographic region all play a role. Lifestyle changes, which include consuming foods and beverages with a high glycemic index, increased food portion sizes, decreased structured physical activity, and increased screen-based sedentary behavior, have influenced the prevalence of obesity.

Antenatal Monitoring

An evaluation of dietary intake and exercise habits can provide insight into women at risk. All pregnant women without contraindications should participate in regular exercise. During prenatal visits women should be questioned and advised about their diet and exercise habits. Where available, nutritional counselling can be a helpful adjunct for women not meeting the weight gain recommendations.

The sonographer’s ability to evaluate fetal structures is largely dependent on maternal size. Approximately 15% of normally visible structures will be sub optimally seen in women with a BMI above the 90th percentile. In women with a BMI above the 97.5th percentile, only 63% of structures are well visualized. Obstetric care providers should take BMI into consideration when arranging for fetal anatomic assessment in the second trimester. Anatomic assessment at 20 to 22 weeks may be a better choice for the obese pregnant patient.

Use all available technical tools improving image quality in obesity: lower transducer emission frequencies; harmonic imaging; compound imaging; speckle reduction filters. Consider approaching the fetus through the four major abdominal areas with least subcutaneous fat: periumbilical area, suprapubic area, right and left iliac fossae. Consider using the transvaginal approach for the assessment of the central nervous system (CNS) in fetuses in vertex presentation.

Gently inform the patient and her partner that obesity will reduce the diagnostic accuracy of the scan. Consider including the BMI value among the demographic data in the report to document the presence or absence of maternal obesity. Report other cofactors of limited acoustic window, such as previous cesarean section (for the scar), twinning and myomata.

Pregnancy Complications

The risk of spontaneous abortion is increased in obese women. Lashen et al. identified an odds ratio for spontaneous abortion of 1.2 (95% CI 1.01 to 1.46) for obese women (BMI > 30 kg/m2). The authors also identified an increased risk of recurrent early miscarriages (more than 3 successive miscarriages < 12 weeks’ gestation) in the obese population, odds ratio 3.5 (95% CI 1.03to 12.01).[8] Similar risks have been identified in obese women undergoing in vitro fertilization treatment [3].

Pre-gestational diabetes is more prevalent in obese women. Therefore, testing during early in pregnancy for women with risk factors is recommended. Obese women are also at increased risk of developing gestational diabetes (GDM). Not surprisingly, obese women are also at increased risk of having a macrosomic child. Physical activity is inexpensive and can significantly reduce the risk of gestational diabetes. More relevant to the obese population, they also reported a 34% reduction in the development of gestational diabetes in women who did not participate in vigorous exercise but who did participate in brisk walking compared with those who participated in easy pace walking. Women with GDM have a 30% chance of developing type 2 diabetes later in life [4].

Intrapartum Complications and Management

Macrosomia and shoulder dystocia

The use of antenatal ultrasound to detect fetal macrosomia is associated with such obstetric interventions as labor induction and cesarean section. The rate of cesarean section is affected. Higher cesarean section is more frequent when ultrasound examination indicates a macrosomic fetus.

Fetal monitoring

The obese abdominal wall may make monitoring more difficult than in other cases, and of course, the positive predictive value of antenatal testing (e.g. cardiotocography, nonstress testing, biophysical profile assessment) is limited. There is no evidence to support the routine use of internal fetal monitoring in this population, but it may be more effective in some women. Monitoring contractions and ensuring adequate labor in obese women poses a special challenge. Obese women require more oxytocin in labor. Consider allowing longer first stage of labor before performing a cesarean for labor arrest. Although most obstetric care providers rely on manual palpation and/or external tocometry, the use of an intrauterine pressure catheter may be advantageous in some cases.

Cesarean section

The risk of cesarean section is increased in the obese parturient. The increase in cesarean section rate may be partly due to the fact that overweight and obese nulliparous women have a slower progression of the first stage of labor. When faced with lack of descent in the second stage of labor, some practitioners may opt for cesarean section rather than operative vaginal delivery because of concerns about fetal macrosomia and shoulder dystocia. This may explain the low rate of operative vaginal delivery in some series [5]. Obese women undergoing caesarean section experience more complications, including blood loss > 1000 mL, increased operative time, increased postoperative wound infection and endometritis, and need for vertical skin incision. The obese diabetic women who undergo cesarean section have an odds ratio for postoperative wound infection of 9.3 (95% CI 4.5 to 19.2), and those who require a vertical skin incision have a 12% rate of wound complication serious enough to require opening the incision [6].

For morbidly obese patients, two standard 50-cm-width operating tables secured together may be necessary. Specially constructed wider operating tables would be ideal. Weighing scales suited for obese patients are necessary not only to measure weight and evaluate weight gain during pregnancy, but also for calculating medication dosages. A wider delivery bed that is easy to move around and that may be used at all stages of delivery, including cesarean section, without the need to move the patient into another bed is most useful. Nursing care of obese patients requires ergonomic adaptation and knowledge about the special risks involved in caring for these patients. More trained nurses are necessary to care for morbidly obese patients.

The decision-to-delivery interval may be longer when an emergent or urgent cesarean section is required in obese parturient. Causes for this delay may include patient transport and bed transfer, the time to establish adequate anesthesia, and the operative time from incision to delivery. The 30-minute rule of emergency cesarean section is an arbitrary threshold rather than an evidence-based standard.

Vaginal birth after cesarean section

In the absence of contraindications, women who have had their first child by cesarean section are asked to consider vaginal birth in subsequent pregnancies. The success of vaginal birth after cesarean section is commonly quoted at 80% [7]. Obese women are less likely than their lean peers to be successful in delivering vaginally after previous cesarean section (VBAC). In women with a BMI > 29 kg/m2 the success rate is 54% to 68% [8]. The success rate is further reduced in even heavier women. Chauhan et al. found a 13% VBAC success rate in women >300 lbs (136 kg) [9].

Thromboembolism

The risk of thromboembolism is high in obese parturients. Edwards et al. reported 683 obese women (BMI > 29 kg/m2) who were matched to 660 normal weight women (BMI 19.8 to 26.0 kg/m2). The incidence of thromboembolism was 2.5% in the obese women, and only 0.6% in the controls.[29] BMI >30 plus one additional risk factor qualify for seven days of postpartum Clexane; BMI >30 plus two additional risk factors require Clexane antenatally and for 6 weeks postpartum; BMI>40 should be regarded as already having two risk factors. Clexane dosage should be calculated by weight:

Early mobilization and T.E.D. anti-embolism stockings are clinically proven to reduce the incidence of deep vein thrombosis by up to 50% and to promote increased blood flow velocity in the legs 138% of baseline by compression of the deep venous system.

Perinatal outcomes

Maternal obesity is also an established risk factor for stillbirth. The reported risk of stillbirth is 2-5 times higher in obese compared with normal-weight women. The risk of stillbirth associated with obesity increases with gestational age. Infant mortality rates increase from 2.4/1000 among normal weight women (BMI 18.5-24.9) to 5.8/1000 among women with grade 3 obesity (BMI ≥ 40.0). Maternal overweight and obesity are associated with increased risks of infant mortality due to increased mortality risk in term births and an increased prevalence of preterm births. Maternal obesity may increase the risk for intellectual disability or cognitive deficits in offspring from 1.3- to 3.6-fold. Maternal prepregnancy obesity and high gestational weight gain of > 18 kg was associated with a 3-fold increase in offspring IQ deficit (mean of 6.5 points lower) [10]. The majority of studies that have examined a link between high maternal BMI and childhood diagnosis of autism spectrum disorders have found a significant positive association. This risk may be further augmented by intrauterine growth restriction (IUGR), preterm birth, high gestational weight gain, gestational or pre-gestational diabetes, and preeclampsia [11].

Conclusion

A national information campaign is required to exploit women’s interest in having as healthy a pregnancy as possible by giving them the information they need to become fit and have a normal BMI before they consider pregnancy. Periodic health check-ups and other appointments for gynecologic care prior to pregnancy offer ideal opportunities to raise the issue of weight loss before conception. Women should be encouraged to enter pregnancy with a BMI < 30 kg/m2, and ideally < 25 kg/m2. Although obesity is not an indication for the transfer of routine obstetric care, consultation with or referral to physicians with expertise in obesity may be appropriate if the obstetrician cannot safely and effectively care for the patient because of the lack of the specialized training, experience or institutional resources.

To Know More About Nutrition and Food Science International Journal 

Please click on: https://juniperpublishers.com/nfsij/index.php

For more Open Access Journals in Juniper Publishers

please click on: https://juniperpublishers.com/index.php

[juniperpublishers-nutrition]

Influence of oligochitosans and highly molecular chitosan on Lactobacillus bulgaricus cultivation

Abstract

It was established that decrease of oligochitosans with molecular masses 7.0, 25.4, 45.3 kDa concentration in the process of Lactobacillus bulgaricus cultivation leads to fermented dairy product pH reduction and titratable acidity increase. Further increase in titratable acidity and decrease of lactic acid microorganisms’ amount was determined during the fermented dairy product storage process. Oligochitosans with molecular masses 7.0, 25.4, 45.3 kDa in concentrations interval from 0.0025 to 0.01 per cent did not exhibit prebiotic properties. Active acidity elevation and titratable acidity depression was observed at the chitosan with molecular mass 350 kDa concentration rises. Also increase of highly molecular chitosan concentration leads to elevation of lactic acid microorganisms’ total amount, which was more than three degree as many as total count of lactic acid bacteria in control sample.

Keywords: Chitosan; Oligochitosan; Lactic acidbacteria; Lactose, Lactic acid fermentation; Lactic acid

Introduction

Starters of the Lactobacillus bulgaricus species pure cultures are widely used for manufacturing of functional fermented dairy products with dietary and health-promoting properties. The prospective way of fermented milks production technological development is enrichment with chitosan [1-3]. Chitosan is a biogenic heteropolymer consists of N-acetylglucosaminaine and glucosaminresidues [2,4]. Chitosan has high molecular mass and soluble in organic acids [5,6]. Low-molecular derivatives of chitosan are represented byolygochitosans with a molecular mass from 2 to 50 kDa, which are well soluble in water. Chitosan and olygochitosans are able to interact with Lactobacillus bulgaricus cells by a different mechanism depending of their molecular mass [7-9]. Teichoic acid negatively charged molecules of lactic acidbacteria cells are capable to multi-point ion binding with positively charged high-molecular chitosan, whereas their cytoplasmic membrane proteins interact with oligochitosans [4,9]. The consequence of this process may be a change in metabolic processes in lactic acid bacteria cells. The goal of research was to study the effect of different concentrations of high-molecular chitosan and oligochitosans with varying molecular mass on lactic acid fermentation process driven by Lactobacillus bulgaricus.

Materials and Methods

Targets of research were skim milk, starter culture of lactic acid bacteria Lactobacillus bulgaricus (producer: Dairy Plant “Stavropolsky”, Russia), chitosan with a molecular mass of 350 kDa and a 95 per cent degree of deacetylation (manufacturer: “Bioprogress LLC”, Russia). Oligochitosans with molecular masses of 7.0, 25.4, 45.3 kDa and 96 per cent degree of deacetyration was prepared by the previously described technique [5]. Dry skim milk was reconstituted to a dry mass concentration of (10 ± 0.2) % by dissolving in distilled water at temperature 30 to 35 °C. Reconstituted skim milk after recombination was characterized by the following parameters: mass concentration of fat 0.15 per cent, mass concentration of protein 3.2 per cent,mass concentration of lactose 5 per cent. The solution of chitosan with molecular mass 350kDa in 2 per cent concentration lactic acid aqueous solution with mass concentration 1 per cent was added into skim milk experimental samples for preparation of mixture with final concentration of chitosan 0.0025, 0.005, 0.0075 and 0.01 per cent respectively. Similar experiments were carried out using oligohitosans with molecular masses of 7.0, 25.4, 45.3 kDa in above mentioned concentrations. The starter culture of Lactobacillus bulgaricus was inoculated in the amount of 3 per cent of the total samples volume after pasteurization of the mixture and cooling to the fermentation temperature of (43 - 45) °C. The end of the fermentation process was determined by organoleptic curd density, as well as by titratable and active acidity. Experimental and control samples were stored during 17 days at 4 ± 2 °С after completion of fermentation process. Following parameters were tested in triplicate during storage of control and experimental samples: pH by potentiometry, titratable acidity by titrimetric analysis and total count of lactic acid bacteria (CFU per gram).

Results and Discussions

The effect of highly molecular chitosan and oligohitosans with a molecular weight of 7.0, 25.4, 45.3 kDa various concentrations on fermented dairy products physical and chemical properties during the cultivation of Lactobacillus bulgaricus and long-term storage process was studied.

As shown in Tables 1 &2, decrease in the concentration of oligochitosans leads to significant decrease in pH and increase of titratable acidity after 20 hours of cultivation.

This is explained by the fact that oligohitosans with molecular masses of 7.0, 25.4, 45.3 kDa in concentrations of 0.0025 and 0.005 percent effectively interact with the proteins of the lactic acid bacteria cytoplasmic membrane. This interaction induces bacterial stress [10]. Consequently, lactose enzymatic hydrolysis and lactic acid production are accelerated resulting in titratable acidity increase. The elevation of oligohitosans concentration leads to promotion of their interaction with bacterial cells teichoic acid molecules. This type of interaction influences on lactic acid bacteria cells cytoplasmic membrane permeability and as a result inhibit rate of lactose metabolism. Highly molecular chitosan concentration variation did not lead to significant changes of pH and titratable acidity of fermented skim milk in comparison with control samples. Chitosan with a molecular mass of 350 kDa puts into effective multi-point ion binding with negatively charged teichoic acid molecules of Lactobacillus bulgaricus cells. This is due to the presence into highly molecular chitosan structure of about 1850 amino groups. Lactose assimilation and lactic acid formation rates are changed depending on highly molecular chitosan concentration.

Physical and chemical properties of fermented dairy products during long-term storage at 4 ± 2 °С were studied after the completion of the Lactobacillus bulgaricus cultivation process. It was established that optimal organoleptic attributes (taste and odor) of fermented product control sample are achieved after 5 days of storage at pH 4.2 - 4.5 and titratable acidity 70 - 140 °T. Organoleptic attributes of this product deteriorated during the further storage.

As shown in Table 3, optimal titratable acidity of fermented milks experimental samples containing oligochitosans at a concentration of 0.01 per cent persisted for up to 17 days. Further increase of titratable acidity of experimental samples containing oligochitosans at a concentration 0.0025, 0.005 and 0.0075 per cent was observed during the storage after the completion of the fermentation process.

Decrease in titratable acidity of fermented dairy product experimental samples was detected when concentration of chitosan with molecular mass 350 kDa increased in interval from 0.0025 to 0.01 percent. Therefore high-molecular chitosan concentration elevation reduces the intensity of lactic acid fermentation in experimental samples. The most powerful process of lactose homo fermentative fermentation inhibition occurred in a sample containing high-molecular chitosan in concentration of 0.01 per cent. The decrease of lactose assimilation intensity by Lactobacillus bulgaricus cells may be propelled by two reasons. The interaction between chitosan molecules and lactic acid bacteria cells cytoplasmic membrane leads to disturbance of membrane permeability for β-galactosidase enzyme, which catalases the reaction of lactose into glucose and galactose hydrolysis. At the same time structural changes in cell cytoplasmic membrane cause retardation of lactose hydrolysis products active transport into bacterial cells.

Thus, there is an inhibition of lactic acid formation in the process of fermented dairy product containing high-molecular chitosan storage, which stimulates the preservation of a large number of lactic acid bacteria. This is confirmed by the data of lactic acid microorganisms ‘quantitative accounting in control and experimental samples after 17 days of storage, as shown in Table 4.

The data presented in Table 4 indicates that oligohitosans with molecular masses of 7.0, 25.4, 45.3 kDa did not affect significantly on Lactobacillus bulgaricus grows rates during fermented dairy products storage process. Addition of highly molecular chitosan in concentrations of 0.0075 and 0.01 per cent in fermented milks increased the content of lactic acid microorganisms,which was more than three degree as many as total count of lactic acid bacteria in control sample.

Thus, tested samples ofoligohitosans with varying degrees of polymerization did not exhibit prebiotic properties and did not prolong the shelf life of fermented dairy products. High-molecular chitosan in a concentration of 0.01 per cent can be recommended as a prebiotic, prolonging the shelf life of fermented milks, manufactured with application of Lactobacillus bulgaricus starter cultures.

To Know More About Nutrition and Food Science International Journal 

Please click on: https://juniperpublishers.com/nfsij/index.php

For more Open Access Journals in Juniper Publishers

please click on: https://juniperpublishers.com/index.php

[juniperpublishers-nutrition]

Cardiovascular Risk as a Context of Care

Abstract

Cardiovascular diseases stand out in terms of high mortality and the association of various cardiovascular risk factors. It is inferred that these involve a context of care with the interrelation of factors that accompany a situation of individual and/or collective cardiovascular vulnerability. This context demands a review and clarification of concepts and the development-based care protocols are in theory s to guide health policies and targeted assistance programs for health promotion and cardiovascular disease prevention in the world.

Keywords: Cardiovascular risk; Context; Care; Health; Prevention of diseases; Promotion of Health.

Opinion

Cardiovascular diseases stand out in terms of high mortality and the association of various cardiovascular risk factors, being the main cause of death in the world, with more than three quarters of these occurring in low- and middle-income countries [1]. Individuals at cardiovascular risk have a double chance of death, three times more likely to develop diseases of the circulatory system and five times more likely to suffer from type 2 diabetes mellitus [2]. It is inferred that cardiovascular risk is a context of care that involves the interrelation of factors that accompany a situation of individual and/or collective cardiovascular vulnerability.

Care in the context directed at people at cardiovascular risk should be developed through disease prevention and health promotion actions, with the potential to generate health indicators in the perspective of collaborating with the advancement of knowledge about the health phenomena involved. In view of this panorama, it is questioned what is the impact of care in the context of cardiovascular risk to be developed by health professionals in the world in which the concept of cardiovascular risk is often linked to cardiovascular disease itself, which seems to hinder the broad and structuring effective care.

Regarding the definition, the concept of cardiovascular risk is underwritten and not clarified, with restriction in punctuating the main factors involved (gender, age, smoking, physical inactivity, inadequate diets, hypertension, diabetes mellitus, dyslipid emia, overweight and obesity) and diseases consequent. In this perspective, it is understood that the definition of the concept of cardiovascular risk, as a context of care, is scarce, despite being widely presented, given the relevance of the theme and the impact on the life of the population, requiring critical analysis to contribute to the advancement in the identification and implementation of care directed at people at risk, regardless of the stratified score.

It is essential to overcome the reductionist view that links cardiovascular risk factors strictly to biological aspects, which can compromise care from the perspective of the complexity and comprehensiveness of interventions developed by health professionals, such as nurses, doctors and nutritionists. These health professionals should investigate cardiovascular risk with a broad view of the concept, understanding it as a context of care, in the varied profiles of patients and their community, with a focus on disease prevention and health promotion at the primary level, thus contributing to advance knowledge about the concept and refine its definition.

he literature also discusses the insertion of the metabolic syndrome in the context of cardiovascular risk, as a central phenomenon, due to the highlight of new and relevant empirical data, such as the psychosocial and cultural factors involved and the perspective of vulnerability in which people with the syndrome are inserted [3]. There is a need to analyze and understand the breadth of the concept of cardiovascular risk as a context of care for use in practice, teaching and research in health and to enable the recognition of the variables involved in this phenomenon to guide health professionals in the identification process human needs of these individuals and care planning.

Conclusion

Care in the context of cardiovascular risk should involve clarifying concepts and developing care protocols based on theories to guide health policies and assistance programs aimed at health promotion and cardiovascular prevention. Health professionals should strive to improve the concept and verify the occurrence of cardiovascular risk in individuals and the community, in order to contribute to the development of care for cardiovascular prevention in this public and to expand the investigation regarding the referred context of health care.

To Know More About Nutrition and Food Science International Journal 

Please click on: https://juniperpublishers.com/nfsij/index.php

For more Open Access Journals in Juniper Publishers

please click on: https://juniperpublishers.com/index.php

[juniperpublishers-nutrition]

Child Care Food Safety Hand Hygiene: The Role of the Director

Abstract

In the United State over 15 million children attend a childcare facility annually. These children are 3.5 times more likely to contract a foodborne illness than children cared for in other settings. Proper hand hygiene practices have been identified as the most important practice to mitigate the spread of foodborne illnesses. Thus, the aim of this study was to explore hand hygiene training opportunities given to childcare food handlers in childcare facilities; as well as explore what food safety training childcare directors currently possess. Results showed directors received food safety training yet did not always pass the training along to their employees. A lack of written hand hygiene policies was identified, as well as lack of childcare employee training for hand hygiene on the topics of hand washing and glove use. It is recommended that childcare directors communicate the importance of proper hand hygiene through microlearning food safety interventions.

Keywords: Childcare; Food safety; Foodservice; Hand hygiene; Training

Introduction

Food safety

Though ample research has been conducted pertaining to food safety and handling practices with numerous interventions tested, foodborne illness outbreaks continue to persist. The four pathogens identified most often in foodborne illness outbreaks are Norovirus (5.5 million), Nontyphoidal Salmonella spp. (1.0 million), C. Perfringens (1.0 million), and Campylobacter spp. (0.8 million) [1]. Of the approximately 5.5 million cases of Norovirus annually, 149 cases result in death and costing over $2.2 billion in economic burden [2]. Among American children under five years of age, Norovirus has been the leading cause of medical visits for acute gastroenteritis [3] and costs an estimated $273 million due to 14,000 hospitalizations, 281,000 emergency room visits, and 627,000 outpatient visits annually. Aside from the economic burden, foodborne illness can lead to severe short-term and long-term health consequences, such as vomiting, diarrhea, organ failure and, in some cases, death.

Childcare food safety

Annually, over 15 million children attend a childcare facility in the United States [4]. On average, these children spend 33 hours per week in some type of childcare facility [4]. Many childcare facilities provide breakfast, lunch, and snacks. Some facilities had designated foodservice employees, while others utilize teachers or parents to supply or prepare food. Each of these methods may be susceptible to unsafe food handling practices resulting from improper hand hygiene.

Research has shown children are 3.5 times more likely to contract FBIs in childcare facilities compared to children cared for in their own homes [5]. It has also been estimated that acute gastrointestinal illnesses associated with childcare facilities cost over $2.3 billion annually [6]. The American Academy of Pediatrics notes the close proximity of children in childcare facilities and their natural curiosity to touch a wide range of objects and surfaces only heightens their risk of infection [7]. Additionally, transmission of enteric pathogens in childcare facilities occurs from person-to-person contact (hand hygiene) due to the close interaction necessary in the care of children, particularly in diapering, toileting, and food service [7,8].

In childcare facilities, researchers have previously investigated food safety knowledge, attitudes toward safe food handling practices, food handling practices, as well as microbial analysis of food contact surfaces and hand hygiene. Wohlgenant et al. [9] examined hygiene and sanitation practices of childcare employees during food preparation in the kitchen as well as during food service in the classrooms to identify pathogen dissemination points. Researchers found the most out of compliance practices were food handlers wearing effective hair restraints, food handlers wearing gloves, sanitizer test kit available for facilities that wash dishes by hand, and availability of a food thermometer. Additionally, microbial analysis showed childcare facilities without a written food preparation policy had significantly higher aerobic plate counts on all surfaces [10]. Kotch et al. [11] identified that proper equipment in hand washing and food preparation areas designed to reduce the spread of infection had a significant effect on reducing illness among the children. The need for childcare workers to follow correct procedures to protect children from any harm, including foodborne illness, remains extremely important [7].

Childcare hand hygiene

Childcare employees play a crucial role in children’s health and safety [12] and must actively work to prevent FBI outbreaks [13]. For example, Fraser et al. [14] used observations to identify frequency of surfaces touched by childcare providers. Staskel, et al. [15] observed childcare cooks demonstrating lack of proper hand washing, nearly 50% used improper techniques. Cosby et al. [16] surveyed bacteriological contamination on selected food contact and non-food contact areas in childcare centers. Li et al. [10] combined observational and microbiological analysis showing facilities without a written food preparation policy had significantly higher microbial contamination on all surfaces than facilities with a written food preparation policy. Kinnula, et al. [17] investigated the use and safety of alcohol-based hand gels (AHGs) among children in childcare centers; Zomer et al. [18] observed childcare employees’ compliance to hand hygiene guidelines and identified environmental determinants of hand hygiene behavior.

Roberts et al. [19] showed through a hand hygiene intervention that proper hand washing in childcare facilities greatly reduced rates of respiratory and diarrheal illness. Hand washing by childcare employees has been identified as the single most important preventative measure to avoid infecting themselves and children with harmful pathogens [20,21].

Thus, the specific research objectives for this exploratory study were to:

1. Assess hand hygiene training opportunities given to childcare food handlers in childcare facilities.

2. Identify what food safety training childcare directors currently possess.

Material and Methods

Sample

The target population for this study was licensed center-based childcare directors in a South Eastern state. Licensed center-based childcare facilities including commercial, church, and preschools. 99 childcare directors were randomly selected from a database of all licensed center-based childcare facilities in the state.

Questionnaire

A paper-based questionnaire adapted from [22] was utilized, consisting of 9 questions to identify childcare facility demographics, and evaluate childcare facility food safety training. The childcare facility demographics section contained 3 questions including: type of childcare facility (i.e. independently owned or operated, chain/franchise); number of food handling employees; and current enrollment. The childcare facility food safety training section contained 6 questions pertaining to food safety policies (2 questions); and food safety training (4 questions).

Data collection & analysis

To reduce sampling error and increase participation rates a survey implementation plan was utilized [23]. In the initial mailing a packet containing:

• Director cover letter.

• Director questionnaire informed consent form.

• Director paper-based questionnaire; and

• Prepaid addressed return envelope. Follow-up contacts spaced approximately one week apart for three weeks, were used to recruit participants [23]. Replacement questionnaires were offered. A final telephone contact to childcare directors was made to those childcare facilities who had not responded.

Data were analyzed using SPSS (Version 23.0). Descriptive statistics including mean, standard deviation, frequency, and percentage were used to summarize the data.

Results and Discussion

A total of 68 of the 99 director questionnaires distributed were completed, for a response rate of 68.7%. The majority of facilities were reported as independently owned/operated (64.7%), withover 60% having 15 employees or fewer, as well as nearly 85% of facilities had 200 or less children enrolled (see, Table 1).

All but two (97%) childcare directors stated they have food safety hand hygiene policies in place, yet 24 directors stated they do not have written hand hygiene policies (see, Table 2). Current study results are higher than previous childcare research, in which 83% of centers reported written procedures for hand washing [10]. The American Academy of Pediatrics’ (2011) recommends having written food handling policies, as they have been shown to increase compliance with proper food handling [7]. The distinction between having “hand hygiene policies” and having “written hand hygiene policies” is important, as the ability to communicate these policies with employees in the form of written procedures has been shown to improve hand hygiene practices [24,25]. Furthermore, previous research has identified the need for clear communication from the director on food safety practices [26]. Of the 68 respondents, 88.2% (n=60) stated they had previously received food safety training, with 70.6% (n=48) receiving a food safety certification as well. The importance of having a director (manager) with proper food safety education has been identified as critical to ensure employees following proper food safety practices [26]. In a study assessing food safety culture in childcare facilities, findings showed childcare employee’s ability to speak freely about food safety practices and communication from directors to employees had a positive effect on employees’ self-commitment to following proper food safety practices [27]. In other words, childcare employees need to feel comfortable speaking and asking questions to the director about food safety practice. However, just as important the director needs to have the food safety knowledge to answer the questions and communication appropriate food handling practices. Previous research in the restaurant setting exploring the influence of food safety climate indicators on hand washing practices found managerial commitment significantly correlated with hand washing frequency [28]. However, finds also showed management rewarding of hand hygiene practices was not related to hand washing frequency. Similar findings were shown in a study on the perceptions of a video game to promote proper hand washing practices, in which respondents did not perceive the video game rewarding or helping to motivate them to increase their hand washing frequency or efficacy [28] (Table 2).

In the current study, over 30% of childcare directors (n=21) reported not providing any training on food safety hand hygiene. Of the 47 directors who reported providing training, 44 (64.7%) indicated providing hand washing training and/or 31 (45.6%) indicated discussing proper glove use as a training topic. These findings are lower than previous childcare hygiene research, in which facility directors reported 94% of centers provided initial food safety training [10].

Due to the high-risk population (young children) in which these childcare employees serve, the need for hand hygiene training to ensure proper food safety handling practices is crucial. Yet current study results show that less than half of directors discuss proper glove use, which could potentially mitigate the spread of foodborne microorganisms. It should also be noted that initial hand hygiene training during new hire orientation is not enough to ensure continuous proper food handling practices. In their research in childcare facilities, Park et al. [29] found the need for further education for the more tenured (10+ years) childcare cooks on proper food safety practices. On-going training and food safety interventions are recommended to ensure new employees are aware of and follow proper food handling practices, but also more tenured employees should receive refresher interventions on food handling practices.

Previous research investigating childcare employees’ perceived barriers to following food safety practices identified respondents perceived they did not need to follow safe food handling practices [25]. This reinforces the importance of the childcare director’s role in communicating not just the “how to handle food properly”, but also the “why food should be handled properly”. Furthermore, previous research has also suggested “evidence-based and customized education and support programs” should be created for educating childcare employees [29].

In a systematic review of foodservice industry food safety training topics & modalities findings showed the average length of training intervention was 6.5 hours [30]. However, “lack of time” and “too much work to do” have been identified as key barriers to following food handling practices and barriers to providing training [25,31]. Therefore, directors need to identify food safety training or interventions that are short as well as inexpensive.

A feasible approach to mitigate identified barriers to training in childcare could be to create multiple short single topic multimodality training interventions (microlearning modules), which combined create a food safety education library. Each of the microlearning training interventions can be completed quickly and can be directly reinforced while on the job the same day. Dolasinski & Reynolds [32] developed a microlearning model applied in the hospitality industry. The authors identified several benefits to utilizing a microlearning approach including inexpensive, quick content delivery, and effective for on-thejob service training. For example, for childcare hand hygiene, a microlearning topic could be “how to wash your hands” (single topic) utilizing an educational poster, short video, and 2-minute director demonstration (multi-modality). This should then be reinforced by the director through observation. This single topic can then be combined with similar hand hygiene topics (when to wash hands, hand sanitizer usage, etc...) to create a larger hand hygiene educational library. This concept can be replicated for various food safety topics (hand hygiene, personal hygiene, temperature controls, etc…) in the childcare setting, as they are inexpensive, short, and provide immediate customized practical information [33].

Conclusion

Proper hand hygiene practices have been identified as the most important practice to mitigate the spread of foodborne illnesses. Thus, the aim of this study was to explore hand hygiene training opportunities given to childcare food handlers in childcare facilities. Additionally, the manager of an operation (childcare director) has a major role in the food safety program at each facility. Therefore, this study also looked to explore what food safety training childcare directors currently possess. Key finds showed directors reported having hand hygiene policies, yet over one third lacked written hand hygiene policies. Additionally, most childcare directors received food safety training, however over 30% did not provide their food handling employees and hand hygiene training. Only slightly more than half the directors reported providing hand washing training, while even fewer provided glove use training.

The results show a clear need for increased childcare food handling employee hand hygiene training. Previous barriers of lack of time and funds have been identified. Yet, childcare directors can utilize microlearning to educate employees on hand hygiene using short, inexpensive, single content modules to mitigate these barriers. The microlearning training can be tailored to the facility’s needs and can be deployed easily on-the-job. Hand hygiene training must be ongoing as well as director observations should occur to ensure continuous proper handling practices.

This study was not without limitations. First, this was a snapshot of childcare directors in one state, at one particular moment. It should be noted that each state creates their own food safety regulations for childcare inspections, thus generalization is cautioned. Additionally, only center-based directors were targeted as home-based facilities are generally smaller and only have one or two employees. However, the current study’s exploratory results help to identify the lack of consistent training for the childcare director as well as the childcare food handler. Future research should assess the use of short customized food safety interventions (microlearning).

To Know More About Nutrition and Food Science International Journal 

Please click on: https://juniperpublishers.com/nfsij/index.php

For more Open Access Journals in Juniper Publishers

please click on: https://juniperpublishers.com/index.php

[juniperpublishers-nutrition]

Pandanus Conoideus Lamk Protects Inflammation by Regulating Reactive Oxygen Species and Nuclear Factor Kappa B in Lps-Induced Murine Macrophages

Abstract

Background: Pandanus conoideus Lamk (Red fruit) is a Papuan traditional food which has been used to treat various diseases. Despite these various effects of Red fruit, little is known about the physiological mechanism. Aims: The aim of this study was to investigate the anti-inflammatory properties of Red fruit oil (RFO) and establish the signal pathway of leading compounds.

Methods: Raw 264.7 murine macrophage cells were used with lipopolysaccharide (LPS). Cell viability and the pro-inflammatory factors were investigated using MTT assay, real time PCR, western blot analysis, and Enzyme linked immuno-sorbent assay (ELISA). The quantification of leading compounds in RFO was performed using high performance liquid chromatography (HPLC).

Results: RFO did not affect cell viability. RFO significantly reduced the production of nitric oxide (NO) and prostaglandin E2 (PGE2), and both the protein level and mRNA level of iNOS in LPS-induced macrophages. RFO also regulated the reactive oxygen species (ROS) in LPS-induced macrophages. RFO attenuated the translocation of NF-κB p65 subunit, phosphorylation of I-κB, extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK) in a dose-dependent manner. HPLC analysis determined that 1 g of RFO had 14.05±0.8 mg of β-cryptoxanthin and 7.4±0.7 mg of β-carotene.

Conclusion: RFO provides an anti-inflammatory effect by regulating ROS and NF-κB through MAPK due to the antioxidant activity.

Keywords: Pandanus conoideus Lamk; Macrophages; Anti-inflammation; ROS; NF-κB; β-cryptoxanthin

Abbreviations: RFO: Red fruit (Pandanus conoideus Lamk ) oil; LPS: Lipopolysaccharide; NO: Nitric oxide; iNOS: Inducible NO synthase; IL: Interleukin; ROS: Reactive oxygen species; ELISA: Enzyme linked immuno-sorbent assay; HPLC: High performance liquid chromatography; COX-2: Cyclooxygenase-2; PGE2: Prostaglandin E2; ERK: Extracellular signal-regulated kinase; JNK: c-Jun N-terminal kinase; MAPK: Mitogen-activated protein kinase; DMEM: Dulbecco’s modified Eagle medium; FBS: Fetal bovine serum; DCFH-DA: 2’7’-dichlorofluorescein diacetate; MTT: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide; RT- PCR: Real time polymerase chain reaction

Introduction

The inflammation process is tightly regulated by both initiation and maintenance signals and considered to be a major risk factor in the pathogenesis of chronic diseases where the macrophages are important immune cells which regulate inflammation producing expression of inflammatory proteins and pro-inflammatory chemokines, cytokines, and nitric oxide (NO) [1,2]. Macrophages are highly sensitive to initiators of inflammation as lipopolysaccharide (LPS) which respond by the release of mediators not only interleukins (ILs) and cytokines, but also inducible NO synthase (iNOS) and reactive oxygen species (ROS), which inducing the inflammatory gene expression where each is associated somehow with the pathophysiological of the inflammation [3-5]. Because macrophages produce a wide range of biologically active molecules participated in both beneficial and detrimental outcomes in inflammation, modulation of macrophage activation is a good strategy to prevent this diseases. Red fruit (Pandanus conoideus Lamk) is Papuan traditional food which has been used to treat various diseases such as cancer [6] preeclampsia [7], hepatitis [8], liver cirrhosis [9], diabetes mellitus [10], and sinusitis [11]. This bioavailability of red fruit has been due to unsaturated fatty acids such as palmitoleic acid, oleic acid, linoleic acid, linolenic acid and some carotenoids [10,12]. Despite these many biological effects, few researches were reported on the mechanism of red fruit oil (RFO). β-cryptoxanthin is a typical carotenoid found abundantly in persimmon, papaya, paprika, and carrot. β-cryptoxanthin has been reported to possess several beneficial functions, such as antioxidant, cancer-preventive effects, and anti-metabolic syndrome effects [13-16]. In present study, we hypothesized that the cause of this anti-chronic inflammation and anti-cancer effect is due to antioxidant function of RFO, and evaluated the anti-inflammatory effect of RFO on LPSstimulated RAW 264.7 macrophage cells. We also investigated the mechanism of inflammatory effect of reduced ROS by RFO in LPS-stimulated macrophages and investigated the component of β-cryptoxanthin in RFO.

Materials and Methods

Chemicals and reagents

RFO (APOTEK®) was supplied from Smile international Co., Ltd (Seoul, Korea). Dulbecco’s modified Eagle medium (DMEM), fetal bovine serum (FBS), and penicillin–streptomycin was purchased from Corning (Oneonta, NY, USA). 2’7’-dichlorofluorescein diacetate (DCFH-DA) and anti-iNOS antibody were purchased from BD (San Jose, CA, USA). Peroxidase-conjugated secondary antibodies and TriZol were purchased from Life technologies (Grand island, NY, USA). Phosphor-JNK, phosphor-ERK, phosphor-p38, phosphor-IκB and NF-κB antibodies were purchased from Cell Signaling Technology Inc. (Beverly, MA, USA). The enzyme immunoassay kit used for prostagladin E2 (PGE2) was obtained from R&D Systems (Minneapolis, MN, USA). The ECL detection reagents were purchased from GE Healthcare (Buckinghamshire, UK). LPS (Escherichia coli 0111: B5) was purchased from Creative Biolabs (Shirley, NY, USA). β-actin, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), and other chemicals were purchased from Sigma–Aldrich (St. Louis, MO, USA).

Cell culture

RAW 264.7, the murine macrophage cell line was purchased from American Type Culture Collection and maintained in DMEM supplement with 1 mg/mL glucose, 10% FBS, 100 mg/mL penicillin-streptomycin at 37 °C with 5% CO2

Cell viability assay

The cytotoxic effect of RFO against RAW264.7 cell lines was evaluated by MTT assay. Briefly, cells were seeded at a density of 5 × 103 cells/well in a 96-well plate for 24 h. Then, the cells were treated with at various concentrations of fractions with or without 1 μg/mL LPS. After 24 h, 2 mg/mL MTT was added onto each well, then incubated until formazan was constituted for 3h. The formazan was dissolved in dimethyl sulfoxide (DMSO) and the absorbance at 550 nm was measured using microplate reader (Molecular Devices, Sunnyvale, CA). Cell viability was calculated as a percentage of viable cells in drugs treated group versus untreated control. Each experiment was repeated three times.

Nitrite assay

Cells were treated with various concentrations of RFO for 30 min and incubated with 1 μg/mL LPS for 24 h. Because NO production is reflected in the accumulation of nitrite in the cell culture medium, 50 μL of supernatants were removed and mixed with the same volume of Greiss reagent (Promega, Madison, WI). After incubation for 10 min, the absorbance of mixture at 450 nm was measured using a spectrophotometer (TECAN, Austria). The nitrite levels were estimated as the percentage of absorbance of the sample to the respective controls.

Cyclooxygenase2 (COX-2) assay

Cells were treated with various concentrations of RFO for 30 min and incubated with 1 μg/mL LPS for 24 h. After incubation, the supernatants were removed and followed COX-2 measurement. The COX-2 concentrations were evaluated using a specific enzyme immunoassay (EIA) kit (Cayman, Ann Arbor, MI) according to the manufacturer’s instructions.

Prostaglandin E2 assay

Cells were treated with various concentrations of RFO for 30 min and incubated with 1 μg/mL LPS for 24 h. After incubation, the supernatants were removed and followed PGE2 measurement. The PGE2 concentrations were evaluated using a specific enzyme immunoassay (EIA) kit (Cayman, Ann Arbor, MI) according to the manufacturer’s instructions.

iNOS gene measurement by real-time PCR

The cells from the supernatants had been removed were subjected to RNA isolation. RNA isolation was performed using TRIzol reagent according to the manufacturer’s instructions. cDNA was synthesized using hyperscript RT master mix (GeneAll, Daejeon, Korea). The primers were described as; iNOS forward: 5′-ATGTCCGAAGCAAACATCAC-3′, reverse: 5′-TAATGTCCAGGAAGTAGGTG-3′, and GAPDH forward: 5′-TGTGATGGTGGGAATGGGTCAG-3′, reverse: 5′-TTTGATGTCAC GCACGATTTCC-3′. The PCR was amplified using ABI 7500 and Taqman gene expression master mix (Applied Biosystems, Waltham, MA, USA). The quantitative analysis was performed to compare the Δ Δ Ct after the normalization by GAPDH as an internal control. After analysis, PCR products were electrophoresed on 3% agrose gel and images were taken by cybergreen detection using Kodak imagestation FX® (Kodak, Rochester, NY, USA)

Analysis of ROS by flowcytometry

Cells were treated with various concentrations of RFO for 30 min and incubated with 1 μg/mL LPS for 24 h. Cells were followed by the addition of 10 mg/mL DCFH-DA). The suspensions were washed with PBS after incubation for 20 min. The suspensions were then assayed with a flowcytometer (C6 Accuri, BD, Bedford, MA, USA) according to Rhee et al. [4].

Western blot analysis

Cells were treated as described previously, then total lysates were prepared with lysis buffer (50 mM Tris (pH 7.4), 300 mM NaCl, 5 mM EDTA (pH 8.0), 0.5 % Triton X-100, 1 mM aprotinin, 1 mM leupeptin, 1mM pepstatin, 10mM iodoacetamide, and 2 mM phenylmethylsulfonyl fluoride (PMSF). Meanwhile, each nucleus extracts and cytosol extracts were isolated using a NE-PER nuclear and cytoplasmic extraction reagent kit (Pierce, Rockford, IL). Briefly, cells were washed with PBS, and were prepared with ice-cold extraction buffers sequentially. After centrifugation at 16,000xg, the cytoplasmic protein and nuclear extract were separated. Total lysates and nuclear fractions were estimated with Bio-Rad dye reagent concentrate (Bio-Rad Laboratories, Hercules, CA), then resolved on a 10% SDS-PAGE. After electrophoresis, the proteins were electro transferred to a PVDF membrane, blocked with 1% BSA, and probed with anti-iNOS (1:1,000), phospho- JNK (1:1,000), phospho-ERK (1:1,000), phospho-p38 (1:1,000), phospho-IκB (1:1,000), and NF-κB (1:500) antibodies at 4 °C overnight. The blot was washed, exposed to HRP-conjugated secondary antibodies for 2 h, and finally developed through enhanced chemiluminescence. For ß-actin detection, previously used membranes were soaked in stripping buffer (62.5 mM Tris- HCl, pH 6.8, 150 mM NaCl, 2% SDS, 100 mM ß-mercaptoethanol) at 65 ℃ for 30 min and hybridized with anti-ß-actin. The relative protein expression was densitometerically quantified using the BioRad GS-670 densitometer (BioRad, Hercules, CA) and normalized to β-actin.

High performance liquid chromatography (HPLC)

To determine the content of β-cryptoxanthin in RFO, we performed HPLC analysis according to previous studies [17]. HPLC analysis was performed using Agilent 1100 model with a pump (G1311C), auto sampler (G1329B), column, and diode array detector purchased from Agilent (Santa Clara, CA, USA). The analysis conditions are described in Table 1.

Statistical analysis

All results are presented as mean ± S.D. and are representing three or more independent experiments. Data were compared using the one-way ANOVA using Prism® (GraphPad, La Jolla, CA, USA) with p-values less than 0.05 considered statistically significant.

Results

RFO did not affect cell viability

Figure 1A showed the effect of RFO on viability of RAW 264.7 with or without LPS. Cell viability was not affected against 10- 1,000 μg/mL of RFO with or without LPS.

RFO reduced NO in LPS-induced macrophages

To assess the effects of RFO on NO production in LPSinduced RAW 264.7 macrophages, cells were treated with various concentrations of RFO for 30 min, then incubated with 1 μg/mL LPS for 24 h. NO release was elevated 224 ± 19.24% (p < 0.001) following LPS treatment, which was reduced 224 ± 19.24% at 10 μg/mL (p < 0.05), 161.38 ± 21.81% at 25 μg/mL (p < 0.001), and 136.16 ± 30.56% at 50 μg/mL (p < 0.001) with RFO combination (Figure 1B).

RFO decreased COX-2 production in LPS-induced macrophages

COX-2 production was significantly increased from 33.17 ± 5.23 ng/mL to 86.25 ± 1.88 ng/mL (p < 0.001) following LPS treatment. However, it was reduced 60.52 ± 12.49 ng/mL at 10 μg/mL (p < 0.05), 32.16 ± 8.85 pg/mL at 25 μg/mL (p < 0.001), and 13.27 ± 1.67 ng/mL at 50 μg/mL (p < 0.001) with RFO combination (Figure 1C).

RFO also decreased PGE2 production in LPS-induced macrophages

Meanwhile, PGE2 production was significantly increased 440.6 ± 35.36 pg/mL (p < 0.001) following LPS treatment, which was reduced 227.5 ± 13.6 pg/mL at 10 μg/mL (p < 0.001), 180.77 ± 48.95 pg/mL at 25 μg/mL (p < 0.001), and 103.27 ± 51.67 pg/ mL at 50 μg/mL (p < 0.001) with RFO combination (Figure 1D).

RFO suppressed both mRNA and protein levels of iNOS in LPS-induced macrophages

To determine the inhibitory effects of RFO on proinflammatory mediator NO, COX-2, and PGE2 production, the biosynthesis of transcriptional levels of iNOS was performed with semi-quantitative reverse-transcription PCR and western blot analysis on LPS-induced RAW 264.7 macrophages. Figure 1D indicates that both mRNA level and protein level of iNOS were significantly decreased by treatment of RFO (p < 0.001). Consistent with the findings shown in Figure 1E, RFO had a significant concentration-dependent inhibitory effect on the inflammation through pro-inflammatory mediator NO in LPSinduced RAW 264.7 macrophages.

RFO attenuated ROS in LPS-induced macrophages

The excess ROS is known to be injured intracellular proteins, lipids and nucleic acids and induce inflammation [18]. Thus, we investigated the ROS production in response to LPS using flowcytometry. DCFH-DA binds ROS produced cells. Figure 2 showed the DCFH-DA positive cells were increased following LPS treatment from 40.71 ± 2.11% to 70.87 ± 3.09%. However, ROS production was also significantly inhibited by RFO with a dose dependent manner; 47.08 ± 2.45% at 10 μg/mL (p < 0.001),41.34 ± 1.41% at 25 μg/mL (p < 0.001), and 33.76 ± 3.56% at 50 μg/mL (p < 0.001).

RFO suppressed nuclear translocation of the NF-κB p65 subunit via MAPKinase

Since p65 is a major component of NF-κB activated by LPS in macrophages, we evaluated the levels of p65 in nuclear extracts by western blotting analysis. Phosphorylation of IκB results in degradation and release of NF-κB, which then translocates to the nucleus. Therefore, we examined whether RFO could prevent phosphorylation of IκB induced by LPS treatment. Figure 3A shows that IκB phosphorylation was increased by treatment with LPS alone in cytosol level, but that such phosphorylation was significantly inhibited in the presence of RFO, similar to results for the nuclear translocation of p65. Taken together, these data suggest that the inhibitory effect of RFO on the LPS-induced translocation of p65 might be involved in the suppression of IκB phosphorylation. To further investigate whether the inhibition of pro-inflammatory mediators by RFO is modulated through the MAPK pathway, we evaluated the effects of RFO on the LPSinduced phosphorylation of p38, ERK, and JNK (Figure 3B). RFO suppressed LPS-induced phosphorylation of p38, ERK and JNK. These results suggest that RFO blocks MAPK pathways to suppress the inflammatory response in LPS-induced RAW 264.7 macrophages.

HPLC analysis of RFO

Table 2 showed the HPLC analysis of RFO. HPLC revealed that 1 g of RFO had 14.05±0.8 mg of β-cryptoxanthin and 7.4 ± 0.7 mg of β-carotene.

Discussion

Inflammation is an immune response that protects our body against host response to infection and injury [19,20]. All inflammatory responses act through mononuclear cells, macrophages, and lymphocytes. Macrophages play on important innate immune effectors and increase pro-inflammatory factors including nitric oxide (NO), prostaglandin E2 (PGE2) cytokines.

The excessive amounts of NO and PGE2 produced by activation of iNOS and COX-2 in response to LPS play an important role in inflammation [21,22]. The overproduction of iNOS-derived NO is involved in the pathology of various inflammatory disorders and tissue damage conditions. A change in the NO level through the inhibition of iNOS enzyme activity or iNOS induction provides a means of assessing the effect of these agents on the inflammatory process. iNOS is implicated in the synthesis of prostaglandin H2 starting of arachidonic acid, which is a precursor of PGE2, in activated macrophages with LPS [23]. In addition, iNOS leads to overproduction of NO, PGE2, and COX-2 which results in the production of inflammatory diseases. Thus, modulation of iNOS and NO expressions could be one of the strategies to reduce inflammatory diseases. The production of inflammatory cytokines is a crucial part of regulating inflammation and tumor progression. The key signaling pathway mediating the inflammatory response, the NF-κB transcription factor, has been well-established in various inflammatory diseases and cancers [24,25]. It is also well known that NF-κB is a significant role factor regulating the expression of inflammation-associated enzymes and cytokine genes, such as iNOS, COX-2, TNF-α and IL-1β, which contain NF-κB binding motifs within their respective promoters [1,26]. Therefore, this signaling pathway is a good target for anti-cancer and antiinflammatory drug development. Many of the upstream kinases and downstream substrates are the same for the each of the major cascades. Our results revealed that anti-inflammatory activities of RFO are mediated through the inhibition of IκB phosphorylation and nuclear translocation of the NF-κB p65 subunit. Besides, these results also indicate that the inhibitory effects of RFO on MAPK and NF-κB signaling are related to a decrease in ROS. It is well known that oxidative stress stimulates ROS production in RAW 264.7 cell line [11,27]. Our data showed the pretreatment with RFO significantly decreased ROS production in LPS-induced RAW264.7 cells using DCFH-DA staining which demonstrated that RFO had a potent to reduce the oxidative stress. We also suggested that RFO regulated MAPK and NF-κB signaling of inflammation operate through oxidative stress. These results demonstrated that RFO could act as scavenging agents or acting on redox state of the cell and other acting as scavenging agents. In previous study, we already demonstrated that RFO regulated the cellular senescence through ROS modulation in H2O2-induced endothelial cells [5].

Carotenoids such as β-cryptoxanthin, β-carotene are one of the antioxidants which are not produced in the human body that must be ingested from outside. Many studies indicated that healthy people had the higher level of β-cryptoxanthin in blood [28-31]. β-cryptoxanthin is the only provitamin A component of carotenoid-based xanthophylls [14,32]. Carotenoids are lipid soluble components that must be ingested with fat to absorb completely in the body. Carotenoids affect the inflammation levels in blood as strong antioxidants and helps purify the blood. Park et al. showed that the daily oral administration of β-cryptoxanthin prevented the progression of osteoarthritis and inhibited proinflammatory cytokines in mice [33]. Therefore, we examined the effects of RFO on the production of several inflammatory mediators and on the expression levels of iNOS in LPS-induced RAW 264.7 macrophage cells. Our results demonstrated that RFO inhibited the expression of iNOS as well as the production of NO and PGE2 and the mechanisms underlying the suppression of the inflammatory response of the NF-κB and ROS. According to the US USDA database, β-carotene content of RFO was significantly higher at 335 times of blackberry, 119 times of broccoli, 13.9 times of pumpkin, and 5.2 times for carrot [34,36]. In addition, β-cryptoxanthin content of RFO was significantly higher at 76 times of orange and 15 times of papaya [30,37]. These findings suggested that RFO might be a beneficial therapeutic agent in the treatment of a variety of inflammatory diseases.

Conclusion

RFO is Papuan traditional food and had been used to treat various disease for long time. In this study, we suggested RFO had an anti-inflammatory effect through regulating inflammatory mediators such as iNOS, COX-2, PGE2, and excessive ROS for the first time. These physiological benefits of RFO may be attributed by regulation of NF-κB transcription. HPLC indicated that large number of carotenoids such as β-cryptoxanthin, β-carotene. This finding may be a synergistic adjuvant therapy for inflammatory diseases by acting as a radical scavenger, ROS inhibitor.

To Know More About Nutrition and Food Science International Journal 

Please click on: https://juniperpublishers.com/nfsij/index.php

For more Open Access Journals in Juniper Publishers

please click on: https://juniperpublishers.com/index.php

[juniperpublishers-nutrition]

Comparative study on some in vitro biological activities of freeze-dried leaves extracts of six advanced accessions of Ipomoea batatas (L.) Lam

Abstract

Sweet potatoes (Ipomoea batatas L.) are an excellent source of bio-active phytochemicals. In recent years, polyphenols and other naturally occurring compounds have become essential research targets for non-insulin-dependent diabetes. Precisely, substances and plant extracts that occur readily have been checked for α-glucosidase (AGH) enzyme inhibition. This study investigated the anti-diabetic, antimutagenicity, and antioxidant activity from sweet potato leaves in vitro. The anti-diabetic activities were tested using the enzyme –α-glucosidase obtained from the rat intestine using the p-nitrophenyl-α-D-glucopyranoside (PNP-G) substrate for inhibitory activities. The α-glucosidase inhibition assay evaluated the anti-diabetic activity, and the extract showed a considerable α-glucosidase inhibitory activity. Among the genotypes, AN-6 exhibited the highest a-glucoside inhibitory activity, followed by AN-4, and AN-2. The leaf extract showed the inhibitory activity ranging from 22.33% to 74.98 on a-glucosidase from 10 to 1000 mg/ml, which was increased steadily with increasing sample concentrations. The antimutagenicity in the leaves explored using the Salmonella typhimurium TA 98. The Ipomoea batatas genotypes effectively decreased the reverse mutation induced by Trp-P-1, and the mutagenic activities were dose-dependent. Furthermore, the extract also capable of reducing the reverse mutation persuaded by Trp-P-2, IQ, and DEGB extract of grilled beef. The AN-6 showed higher antimutagenicity followed by AN-5 at 100 μL concentrations. The fallouts demonstrate that antioxidant capacity (4.42 to 10.98 μmole Trolox g-1 DW) and total phenolic contents (7.68 to 16.96 μmole TA. g-1 DW) broadly fluctuate among the genotypes. Our data demonstrate that all the genotypes have the physiological functions studied, and AN-6 and AN-4 exhibited the highest activities. The sweet potato leaves extract showed a more potent inhibitory activity for all the physiological functions studied, which might have values in anticipation of certain human health conditions.

Keywords: Antioxidant; Polyphenol; Anti-diabetic activity; Antimutagenicity; Sweet potato tops

Introduction

Sweet potato (Ipomoea batatas L. Lam) is the sixth most important food crop in the world, and new uses for this crop have been identified [1]. It is one of the diversified crops supplying vitamins and minerals such as vitamin A, B, C, beta-carotene, iron, calcium, zinc, protein and has high energy [2]. Fresh leaves contain vitamin A on an average of 1600 IU 100g-1 [3]. Leaves are very nutritious compared to leaves of cassava, amaranth, mushrooms, taro and pumpkin [4]. It is also one of the plants selected by the US National Aeronautics and Space Administration to be grown in a controlled ecological life support system as a primary food source [5]. Recent studies show that it contains bio-active compounds as polyphenols, anthocyanins, flavonoids, dietary fiber, etc., which are essential for human health. Sweet poato storage roots are a source of carbohydrates, while its leaves and green stems contain nutritional compounds in higher than many commercial vegetables [6-8]. Sweet potato leaves are cooked as vegetables in different locations of the world. The eating of Ipomoea batatas L. leaves as a vegetable in many parts of the world indicates that they are acceptable as edible like other traditional leafy vegetables. They are rich in phytonutrients and are further tolerant of diseases and pests than many other green plants [9-12]. Phytonutrients act as bioactive composites and a diverse group of secondary metabolites commonly present in higher plants [7,13-19]. They play important roles and contribute to the structure of the plants and complicated by a significant number of metabolic pathways [20,21]. Thus, the phenolic plant complexes, because of their diversity and widespread distribution, are the most exceptional talented group of natural antioxidants and add to the organoleptic and nutritional qualities of fruit and vegetables.

Diabetes mellitus is a common disease with many complications, such as atherosclerosis, cardiac dysfunction, retinopathy, neuropathy, and nephropathy [22]. α-glucosidase (EC 3.2.1.20) catalyzes the final step in the digestive process of carbohydrates. Its inhibitors can retard the uptake of dietary carbohydrates and suppress postprandial hyperglycemia and could be useful for treating diabetic and obese patients [23]. α-Glucosidase inhibitors such as acarbose, miglitol, and voglibose are known to reduce postprandial hyperglycemia primarily by interfering with the carbohydrate digestive enzymes and by delaying glucose absorption. Free radicals can lead to a variety of physiological and biochemical lesions [24] and induce degenerative diseases such as coronary disease, diabetes, stroke, and cancer [25]. The new expansion of screening approaches for environmental carcinogens by determining their mutagenicity has allowed detecting numerous types of mutagens and carcinogens in foods [2,24-27]. On the other hand, it is now recognized that several types of inhibitors act against mutagens and carcinogens in food. They show a substantial part in plummeting the dangers of mutagenesis and carcinogenesis [28]. Several authors described that the nutritive constituents of sweet potato tops are comparable to those of commercial leafy vegetables [2,6,14-18,26,29-30]. However, the physiological function of sweet potato leaves has not yet been deliberate synthetically. In the current article, the effects of the extracts of the selected sweet potato accessions with the diverse polyphenolic levels on the antidiabetic activity, mutagenicity, and antioxidant capacity are explored.

Materials and Methods

The leaves from six Ipomoea batatas L. (sweet potato) advanced accessions, namely AN-1, AN-2, AN-3., AN-3, AN-4, AN- 5, and AN-6, were used for this study. Sweet potato roots were planted 2 inches deep and about 2 inches apart (density of 5 cm x 5 cm) in a greenhouse and field conditions in late February (greenhouse) to March/April in the University of Arkansas at Pine Bluff’s Agricultural Research Farm, Pine Bluff, AR. After two months, tips were harvested every 10-15 days. Chemical fertilizer (N: P: K = 8: 8: 8) was used at a rate of 500 lbs/acre, and compost was used at a rate of 8000lbs/acre in volume. After each harvest, 150 lbs/acre of ammonium sulfate was applied as additional fertilizer. After harvest, the leaves were washed softly, moved into pre-labeled separate vinyl bags, and directly frozen at -85 ℃. The next day all the frozen samples were freeze-dried for 48 h in a freeze dryer. The freeze-dried samples were ground in a blender and used for laboratory analysis. The extract was prepared from the lyophilized flour (1g) using 20 mL of ice-cold water for 1h. The suspension was centrifuged at 18000 x g for 20 min, and the resultant precipitate was re-extracted under the same conditions. The collected supernatant was lyophilized and used for analysis.

α-Glucosidase inhibitory assay

The α-Glucosidase inhibitory assay was performed according to a slightly modified method described by Islam [31]. One hundred microliters of 3 mM pNPG in 0.2 M sodium phosphate buffer (pH 6.8) was added as a substrate to the mixture of 50 μl of α-glucosidase (0.15 unit/ml) and 50 μl of sample to start the reaction. The reaction was conducted at 37 ℃ for 15 min and stopped by the addition of 750 μl of 0.1 M Na2CO3. The α-Glucosidase activity assessed by measuring the release of p-nitrophenol from pNPG at 405 nm. Acarbose used as a positive control. All tests were performed in independent triplicate (n=3), and data were expressed as mean ± SD.

Extraction and Measurement of Total Phenolic

The total phenolic contents of the extracts were measured according to a slightly modified method described by Islam et al. [18]. The lyophilized sweet potato leaf extract was forcefully mixed with ten times its equivalent volume of 80% ethanol. The mixture was boiled for 5 min and centrifuged at 5000g for 10 min, and the supernatant was composed. The residue was mixed with an additional 80% ethanol and boiled for 10 min to re-extract the phenolic and centrifuged under similar conditions. The extracts were pooled and made up to 10 mL and used for to quantity of total phenolic. The alcohol extract was diluted to achieve an absorbance reading at the range of the standard tannic acid (TE). The results were stated as μmol TE g-1 DW (dry weight).

Antioxidant capacity in the DPPH assay

The radical-scavenging activity of the extracts was measured according to a slightly modified method described by Islam et al. [17]. A stock solution of DPPH (6 mM) was prepared by dissolving 0.0263g in 10 ml of ethanol (or methanol). The stock solution is diluted to develop a 60 μM working solution. Again, a ten mM stock solution of Trolox was ready for every sample tested. Dilutions were made for each sample tested. Dilution strength was dependent upon each extract’s relative antioxidant capacity. For each dilution, 20 μL were added to 2.5ml of DPPH solution and incubated in a dry bath at 37 ˚C for 30 min. Absorbances were measured at 520 nm on an ASYS UVM 340 plate reader. TEAC values were measured by comparing the slope of sample plots to the slope of Trolox. Antioxidant activity was reported as μmoles Trolox equivalent per gram dry weight sample (μmol TE/g DW).

Assay of antimutagenicity

The antimutagenicity assay was performed as described in earlier papers [27]. The antimutagenic activity was assessed for Salmonella typhimurium TA 98 using a mutagen, Trp-P-1. These mutagens need metabolic activation to induce mutation in TA 98. The s-9 mix containing 50 μmol of sodium phosphate buffer (pH 7.4), 4 μmol of MgCl2, 16.5 μmol of KCl, 2.5 μmol of glucose-6- phosphate, two μmole of NADH, 2 μmol of NADPH, and 50 μL of the S-9 fraction in a total volume of 0.5 mL. For the inhibition test, 0.1 mL of mutagen, 0.1 mL DMSO-dissolved polyphenolics solution, and 0.5 mL of S-9 mix or phosphate buffer were concurrently incubated with 0.1 mL of a bacterial suspension at 37 ℃ for 20 min and then dispensed into minimal-glucose-agar plates with 2 mL of soft agar. The colony number of each dish was accounted after 48 h cultivation at 37 ℃.

Statistical analysis

A randomized complete block design with three replications was adopted. Data for the different parameters were analyzed by analysis of variance (ANOVA) procedure, and the level of significance was calculated from the F value of ANOVA.

Results and Discussion

α-Glucosidase inhibitory effect

The α-glucosidase inhibition assay evaluated the antidiabetic activity, and the extract showed a considerable α-glucosidase inhibitory activity (Table 1). The leaf extract demonstrated a moderate to high inhibitory activity on α-glucosidase, among the genotypes, AN-6 (80% inhibition at 1000 μg/ml) exhibited the highest a-glucoside inhibitory activity, followed by AN-4 (75% inhibition at 1000 μg/ml) and AN-2 (80% inhibition at 1000 μg/ml). The results also suggested that the α-Glucosidase inhibitory effect in the sweet potato tops is dose-dependent (Table 1), and increasing the doses resulted in a higher rate of inhibition percentage. The leaf extract showed the inhibitory activity ranging from 22.33% to 74.98% on a-glucosidase from 10 to 1000 mg/ml, which was increased steadily with increasing sample concentrations. On the other hand, the control treatment (Acarbose) showed 98.01% inhibitory activity at the strength of 0.1 μg/ml.

One therapeutic approach for treating diabetes is to increase postprandial hyperglycemia. This is done by retarding the absorption of glucose through the inhibition of the carbohydrate hydrolyzing enzyme α-glucosidase in the digestive tract. Inhibitors of these enzymes delay carbohydrate digestion, causing a reduction in the rate of glucose absorption and consequently blunting the postprandial plasma glucose rise (Rhabasa and Chiasson, 2004) [32]. The results suggest that the Ipomoea batatas leaf extracts have the potentiality for treating diabetes by inhibiting α-glucosidase activity.

Total polyphenol content and antioxidant capacity

The antioxidant capacity (μmole Trolox/mg dry leaf powder) and total polyphenol (μmol TE g-1 DW) in the leaves of three genotypes are presented in Table 2. The genotypes fluctuated extensively in their total polyphenolic contents. The highest total phenolic found was 16.98 μmol TE g-1 DW, and the lowest was 7.68 μmol TE g-1 DW. The accessions AN-6 had higher content (16.98 μmol Trolox.g-1 DW) flowed by AN-4 (16.52 μmol Trolox.g-1 DW), and AN-5 (15.63 μmol Trolox.g-1 DW). The results showed that sweetpotato leaves had higher or similar content of total polyphenolics than other vegetables [12,17-18,21,29]. The data also suggested that there was a positive correlation between polyphenol contents and antioxidant activity. Because the accessions higher in total phenol contents also exhibited higher antioxidant activity. The above results also agree with the observations of Islam [6], where he added that sweet potato leaves, could serve as a new leafy vegetable. Acceptable tops should be tender, glabrous, and purplish. Those eating tops prefer the top 10 cm of tips, including both stem and leaves. Heads with the most significant number of leaves with petioles less than 4/10 of 1cm long are considered desirable because they are tender and suitable for vegetables. Petiole length varies widely with genotype and may range from approximately 10 to 40 cm [33]. (Table 2)

The antioxidant capacity of the genotypes ranges from 4.42 to 10.98 μmol Trolox g-1 DW. The accessions AN-4 (10.98 μmol Trolox.g-1 DW) had the highest contents of phenolic, followed by AN-6 (10.69 μmol Trolox.g-1 DW). The accessions AN-1 showed the lowest (4.42 μmol Trolox.g-1 DW) antioxidant activity followed by AN-2 (5.75 μmol Trolox.g-1 DW). The phenolic is pervasive bioactive compounds found in plant foods and beverages. The polyphenolic compounds show numerous biological functions, sweet potato leaves might also be expected to have physiologically active possessions because they comprise higher contents phytonutrients. The antioxidative substances contained in plant parts have attracted much consideration all over the world. Several researchers [17,27,34] have reported the radical scavenging and antioxidant activities of sweet potato leaves. The polyphenolics contents and antioxidant activity in sweet potato leaves, other different plants and foods showed a high correlation [6,16,17,26]. Usually, the antioxidant capacity of various plants is influenced by the genetic factor. Therefore, the extent of the antioxidant capacity may be a critical tool for use in plant breeding programs intended to improve antioxidant components available for human consumption. This result will be valuable for some chemical breeding programs to develop needed organoleptic and nutritional quality characteristics of crop plants.

Effects of water extract of leaves on the mutagenicity

The antimutagenic impact of the water extracts from sweet potato leaves of three genotypes were determined by antimutagenicity assays using Trp-P-1 at a dose of 0.075 μg/plate, and using three different doses of the sweet potato leaves extracts such as 100, 50 and 10 μg/plate (Table 3).

The results found that inhibitory activity was higher at higher doses in all genotypes studies. The inhibitory activity (%) ranged from 69 to 94 at 100μg/plate, 68 to 84 at 50μg/plate, and 61 to 73 at ten μg/plate doses. The highest activity found in the accessions AN-6 (90% inhibition at 100 μL) followed by AN-5 (92% inhibition at 100 μL) while AN-2 (80% inhibition at 100 μL) had the lowest. Therefore, the results propose a wide disparity of antimutagenicity among the genotypes, and the extracts showed dose-dependent inhibitory activities. Similar trends were also found by several researchers [6,17,35,36]. The antimutagenic effect of the extract at low doses is relatively minor compared with the one from higher doses. (Table 4)

We also evaluated the antimutagenic activity of the extract using several mutagens, such as Trp-P-2, IQ, B[a] P, and DEGB (Table 4). The DEGB was utilized at a dose of 100 μL/plate without dilution. The s-9 mix was added for the assay using Trp-P-1, Trp-P-2, IQ, B[a] P, and DEGB to cause mutations in TA 98. The extract used in doses of 50, 10, and 5 μL/plate. The extract inhibited Trp-P-2 induced mutation by 14%, IQ by 88%, b[a] P by 27%, and Trp-P-1 by 71%, respectively, at the concentration of 10 μL/plate. Thus, the sweet potato leaf extract effectively decreased the reverse mutations induced by all purified mutagens tested. This study exhibited that Ipomoea batatas L. tops could be an outstanding source of natural active compounds with numerous biological functions with the aptitude to defend in contradiction of certain sorts of human illnesses. We tested several physiological functions of the leaves extracts in six advanced accessions. All the accessions tested accumulated higher physiological functions. The high biological activity in the leaves extracts, which might have values in the prevention of specific human conditions. Therefore, sweet potato leaves can be considered as a potential source of functional food and a pharmaceutical agent. Furthermore, the leaves with high phytonutrient content may be used as herb, tea, food ingredient, and a nutritional supplement that could be demanded to have a positive impact on human health.

To Know More About Nutrition and Food Science International Journal 

Please click on: https://juniperpublishers.com/nfsij/index.php

For more Open Access Journals in Juniper Publishers

please click on: https://juniperpublishers.com/index.php

[juniperpublishers-nutrition]

Ensuring Athlete Immunity Through Nutrition During the Pandemic Period

Abstract

The aim of the study was to provide recommendations for increasing the immunity of athletes through regular training as well as nutrition during the pandemic period. Coronavirus (Covid-19) infection, considered a pandemic by the World Health Organization [37], poses a significant threat to public health as well as to athletes around the world. While the danger of new types of coronavirus has been observed in the world increasing day by day, it stresses the importance of athlete’s attention to prevention measures for Covid-19 as well as strengthening the immune system. Although there is no vaccine to prevent or treat coronavirus transmission alone, it is known that healthy and balanced nutrition of athletes strengthens the immune system along with planned and programmed training / physical activity and regular sleep. The healthier nutrition of athletes, when evaluated in the context of the coronavirus pandemic, contributes greatly to improving the performance of healthy athletes, along with training and genetic factors. The higher the athlete’s knowledge about athlete nutrition, the higher the rate of application. If we consider the performance of both themselves and the athletes they will train in the future, awareness about athlete nutrition is very important. Health professionals, point out that keeping immunity strong in this process is important because Covid-19 disease degree and risk of death are associated with weakening in the immune system; They say that a diet enriched with vitamins, minerals and antioxidants reduces the risk of developing infectious diseases. As a result of the study, athletes will learn the right nutrition ways and gain immunity, which becomes even more important during the pandemic period.

Keywords: Nutrition; Athletics; Pandemic; Covid-19, Immunity

Abbreviations: COVID-19: Coronavirus Disease 2019

Introduction

Thousands of people around the world are struggling with this epidemic because of the coronavirus that is experienced in the world, which the World Health Organization also accepts as a pandemic. So, how should it be fed during this period? Many scientists related to coronavirus are working intensively on treatment and healing processes Coronavirus, the immune system is weak and chronic disease people under the influence of more. Because of this epidemic, the importance of strengthening our immune system comes to the fore once again. The solution to this disease is of course not possible with just a medical diet plan, but healthy eating, regular sleep and physical activity can help strengthen our immune system. You should take steps to strengthen your immune system before you catch coronavirus. For this reason, you can start by increasing your consumption of vegetables and fruits first [1].

The source of the word nutrition is the word nutria, a Latin word [2]. According to the World Health Organization, nutrition is the intake of foods that are needed in connection with the body’s dietary requirements. Good nutrition, an adequate, balanced diet combined with regular, physical activity, is one of the cornerstones of Health. Poor nutrition can lead to decreased immunity, increased susceptibility to disease, poor physical and mental development, and decreased productivity [3].

Of all the sub-disciplines of sports and exercise science, sports nutrition has been the most important in the past decade [4]. Athletes should seek guidance from qualified sports nutrition professionals who can advise on individual energy, nutrient and fluid needs, and help develop sports-specific nutrition strategies for training, racing and recovery [5]. Coaches have significant effects on their athletes, even in the field of sports nutrition [6].

But in our country, the only profession that is trained in athlete nutrition and can write a diet for athletes is dietitian. Therefore, it will contribute to the performance of athletes to receive nutritional advice from dietitians who are experienced in athlete nutrition. The sports nutritionist should stay up to date on the role of nutrition on training so they can provide athletes with honest and accurate information about the role of nutrition and dietary supplements on performance and training [7]. Therefore, athletes should be referred to a registered dietitian nutritionist for a personalized diet plan [8].

Specific nutritional goals should be set to improve the performance of athletes. Nutritional goals vary from athlete to athlete, the type of sport and the performance expectations of the athlete. The training period of the athlete and the nutrition plan of the competition 4 period also changes. Nutrition goals during competition periods meet the body’s need for fuel and improve performance. Improving the performance of athletes is not a condition to be provided with a daily diet. It is a long process for the athlete to train regularly, adapt to the athlete’s nutrition plan, increase the muscle glycogen stores, and meet the novelties needed during the competition.

Whether you are an athlete or just going to exercise, prefeeding with exercise workouts is important for all levels of exercise. Fluid consumption and the type of fluid before exercise or training are also critical [9]. The importance of hydration for performance is undeniable. The athlete’s body temperature increases during training or competition. The body begins to sweat in response to this condition. With sweating, loss of water and certain minerals occurs in the body. Not only the athlete’s body temperature, but also the temperature and humidity of the environment, such as the circumstances affect the sweating.

Immune system and phytotherapy

Plants have been used in medical treatment throughout human history. Today, interest in herbal treatment has increased all over the world. Plants have also been a guiding resource for synthetic drugs. Viruses, which are the main causes of their disease, trigger a series of diseases by weakening the immune system of the living thing and cause some important diseases [10]. These diseases are a major health issue as effective drugs against Viral infections are still not developed [11]. The effects of antiviral drugs developed today are limited. Given the structural diversity and numerical multiplicity of plant components present in nature, the plant world is a promising resource for new antiviral treatments [12].

There are studies showing that effective results are obtained with Phytotherapy related to strengthening the immune system. Tea made from black elderberry, ginger, sage, black pepper, and balm leaves strengthens the immune system. The flavonoids and anthocyanins in the elderberry plant have an antioxidant effect as well as stimulating the immune system and increasing the body’s resistance [13].

The antiviral effect of Melissa Officinalis aqueous extract, which is common in our country and known as Son weed and is used for the healing effect of herpes especially from daily ailments, against herpes virus was proved by researchers in 2 clinical trials and 3 in vitro studies. Clinical trials for the antiviral effect against Herpes Labialis virus and in vitro studies against HIV, Influenza and Vaksinia viruses, respectively.

As a result of the studies, melissa cream showed positive results in reducing complaints and treating infections in Herpes simplex lesions. The volatile components contained in Sage are known to be beneficial in infections and inflammation (pharyngitis, jinjivitis, etc.) that settle in the mouth and throat [14]. In recent years, the effects of piperidine in black pepper on the central nervous system, stimulants, painkillers, and feverreducing effects have also been identified. Omega-9 fatty acids found in oils such as olive oil and nut oil also positively affect the immune system.

The effects of food on immunity

Vitamin A: Vitamin A is a powerful vitamin in yellow, orange and green vegetables and fruits such as eggs, milk, fish, spinach, oranges, carrots, yesilbiber, apricots, and certain amounts of these foods play an important role in preventing diseases. Vitamin A is a powerful antioxidant vitamin that fights free radicals, promotes skin and eye health, Fights Cancer by blocking DNA mutations in cancerous cells and delays aging. In foods, vitamin A is found as retinol and vitamin A precursor carotene. The daily requirement is 1000mcg for adult male and 800mcg for female.

Vitamin C: Vitamin C helps to remove harmful substances from the body and strengthens the defense system. Green pepper, parsley, Cress, arugula, cauliflower, spinach, orange, lemon, tangerine, rosehip contains plenty of vitamin C. To prevent vitamin C loss, salads should also be prepared just before they are consumed, such as fruit juices. The deficiency can cause symptoms such as immune system, gingivitis, and easy bruising. Conversely, getting enough can help protect against disease and infection, increase iron absorption, and even reduce the risk of painful conditions such as gout. 3 servings of fruit should be consumed every day to increase the consumption of vitamin C, besides adding plenty of lemon salad must not neglect to your meals. The amount required to take Vitamin C daily is 50-75mg per day for adults.

Vitamin E: The most important feature of vitamin E is that it is a powerful antioxidant. Nuts, walnuts, almonds, Yesil seeds, oils, green leafy vegetables, dried legumes are rich in vitamin E. Daily requirement for adults is 8-10mg/day.

Vitamin B12: Vitamin B12, also called cobalamin, is a watersoluble vitamin that is present in every cell of the human body. Vitamin B12 is the largest of the eight vitamin B varieties. B12 deficiency is thought to be one of the leading nutrient deficiencies in the world. Vitamin B12, which protects against depression, benefits our mood, energy levels, memory, heart, skin, hair, digestion and much more. It is also an essential vitamin in adrenal gland insufficiency, enzyme production, formation of multiple metabolic functions including DNA synthesis and hormonal balance, and protection of nervous and cardiovascular systems. The amount of B12 that should be taken daily is recommended for adults between 2-3 micrograms/mcg and 4-7 micrograms/ mcg per day. The amount of need in pregnant women and breastfeeding is increasing.

Vitamin D: Vitamin D strengthens healthy bone structure and immune system, helps prevent depression and insulin resistance, can have anti-cancer properties. The amount of Vitamin D needed to be taken daily is around 4000 units per day and 1000-1500 units in the first age. Vitamin D regulates calcium and phosphorus absorption and metabolism and plays a key role in maintaining bone health [8].

Vitamin K: It is an important fat-soluble vitamin that plays an important role in bone and heart health. It is one of the main vitamins involved in bone mineralization and blood clotting, as well as helping to maintain brain function, maintain a healthy metabolism and protect against cancer. The daily dose of Vitamin K required for adults is 65-80MCG.

Omega-3: Omega-3 fatty acids found in fish, fish oil, nuts and walnuts are a powerful antioxidant, and Omega-9 fatty acids found in oils such as olive oil and hazelnut oil also positively affect the immune system in strengthening the immune system.

Iron: Iron deficiency, with or without anemia, can impair muscle function and limit work capacity 78,81 leading to compromised training adaptation and athletic performance. Suboptimal iron status often results from limited iron intake from heme food sources and inadequate energy intake (approximately 6mg iron is consumed per ~1,000 kcals). 82 Periods of rapid growth, training at high altitudes, menstrual blood loss, footstrike hemolysis, blood donation, or injury can negatively impact iron status. 79,81 Some athletes in intense training may also have increased iron losses in sweat, urine, feces, and from intravascular hemolysis [8].

Zinc: Zinc is one of the most effective minerals that boosts the immune system, reducing the frequency of life-threatening infections. The best sources are animal-derived foods such as red meat and shellfish and liver. Zinc is found in animal protein sources such as meat, fish, eggs, as well as pumpkin seeds and almonds.

Probiotics: Myco organisms that help regulate the digestive system and thus positively affect immunity are called “probiotics”. Probiotics help the gut’s natural flora to create a barrier against all kinds of pathogens, namely harmful organisms that cause disease. A large part of the immune system’s cells is found in the intestines, and having strong intestines means that the immune system is also strong. Yoghurt contains probiotics that strengthen both the gut flora and the immune system. Because it regulates the intestinal flora, it lowers the risk of colon cancer, and because it strengthens immunity, it increases resistance to allergic diseases. Yogurt has a low lactose content compared to milk. For this reason, yogurt consumption is appropriate for individuals who cannot tolerate milk.

Calcium from yogurt also speeds up fat burning. Yoghurt also contains potassium, phosphorus, riboflavin, iodine, zinc, vitamins A, E and B. This makes yogurt a powerful protective food against gastrointestinal disorders, bad cholesterol leading to hypertension, and cardiovascular diseases. In addition, it was determined that the risk of breast cancer decreased due to the consumption of fermented dairy products, especially yoghurt [15].

Honey, garlic, and black elderberry: Honey is used as a natural remedy for infections in the mouth, throat, and bronchi. Garlic also contains high amounts of saponin, phosphorus, potassium, sulfur, zinc, moderate amounts of selenium, vitamins A and C, and small amounts of calcium, magnesium, sodium, iron, manganese, and B complex vitamins. The drugs prepared from the fruits of black elderberry are used in the treatment of upper respiratory tract infections. Black elderberry has both an immuneboosting effect and an antiviral effect. With the right choice of foods, we consume and the fact that we can fight many diseases with protective or therapeutic plants, we can live a healthier life with the right treatment approaches of specialist physicians and the possibilities of today’s medicine. It is important to remember that herbal treatments and foods may have interactions with the drugs we use, that is, they may decrease and increase the desired effects of the drugs. Before applying these treatments, the physician who has undertaken the treatment should be consulted.

Foods to be avoided in Coronavirus outbreak: Food and beverages that should be limited during this period; sugar and sugary foods and beverages that rapidly increase blood sugar, pastry products including white bread, processed meat products, foods containing excess salt (ready sauces, salty products such as chips, popcorn, salty cookies, etc.). The consumption of alcoholic beverages with high energy content should be limited as much as possible since they can negatively affect the absorption of vitamins and minerals and lead to sleep problems. There is no evidence that alcohol consumption prevents coronavirus infection, and fake drinks containing methyl alcohol instead of ethyl alcohol can cause very serious poisoning [16].

Carbohydrates and athletic performance: Multiple transportable carbohydrates, ingested at high rates, can be beneficial during endurance sports in which the duration of exercise is 3h or more. Carbohydrates are organic compounds composed of carbon, hydrogen, and oxygen elements. Carbohydrates, proteins, and fats meet the body’s energy needs. 55-60% of a healthy individual’s energy needs are provided by carbohydrates (Wallis).

Carbohydrates are converted into glycogen and stored in the body, novelties, and liver. But these stores are limited [17]. Athletes use a range of dietary strategies to improve performance, maximizing glycogen stores is an important strategy for many people [18].

According to the type of sports and the needs of the athlete, the carbohydrate needs of the athlete should be determined and it should be ensured that the athlete consumes the nutrients he needs in time. Only in this way can optimal performance be achieved for the athlete. Carb needs of the athlete; the body type of the athlete, the training situation, the type of sport performed, the season, the pre-season period, the preparation period, the sex of the athlete and the age of the athlete. The formation of the nutrition plan experienced dietitians and the compliance of the athlete with the nutrition plan can contribute to the performance of the athlete. However, it is necessary to evaluate carbohydrate consumption well. Carbohydrate, which is more than the athlete’s need, will be stored as fat in the body. It should be considered that the carbohydrate and energy requirements of the athlete are different during training days, non-training days and race days [19]. The ingestion of a combination of different types of carbohydrate during exercise results in high rates of muscle glucose oxidation (1.5g/min) and can improve intense, shortduration (∼60min), and prolonged (>90min) submaximal steadystate exercise, either by metabolic or neural mechanisms.

Protein and athletic performance: Protein consumption in the immediate pre- and post-exercise period is often intertwined with carbohydrate consumption as most athletes consume foods, beverages, and supplements that contain both macronutrients [8]. Strength and endurance athletes indicate that, in fact, exercise does increase protein/amino acid need. Proteins are one of the three macronutrients that provide the energy people need, such as carbohydrates and fats [20]. The Latin equivalent of the word Protein is the essential nitrogen element for living beings. Protein is the structure of the living cell, which is the smallest part of the body, and the enzymes that catalyze metabolic reactions. Protein is essential for growth since growth means the proliferation of cells [17].

The main determinants of an athlete’s protein need are the training regime and the usual nutritional intake [21]. Protein needs should be properly regulated in the daily nutrition plan of the athlete and the athlete should comply with the specified amounts. The daily recommended amount of protein for a Normal person is 0.8g/kg/day [22,23]. Assuming total energy intake is sufficient to cover the high expenditures caused by daily training, a diet containing 12 to 15% of its energy from protein should be adequate for both types of athletes.

Fat and athletic performance: Fat is a necessary component of a healthy diet, providing energy, essential elements of cell membranes and facilitation of the absorption of fat-soluble vitamins. Body fat and carbohydrate stores provide the major sources of exercise fuel; whereas fat sources (plasma free fatty acids derived from adipose tissue and intramuscular triglycerides) are relatively plentiful. Approximately 9kkal of energy is obtained from fat, which provides twice the energy of carbohydrates and proteins. However, as more oxygen is needed during the conversion of fats into energy compared to carbohydrates, fats are not as favorable energy source as carbohydrates. In our daily diet, excess fat is stored in the body and used to create energy when necessary [24].

Fat is a necessary component of a healthy diet and maintaining an adequate intake of fat is crucial to meeting the nutritional requirements of essential fatty acids and fat-soluble vitamins, vitamins A, D, E and K [22,25]. Oil consumption must be 25% or less of daily energy [26]. For athletic performance, fat consumption must come from at least 20% of total energy, according to Clifford and Maloney [22].

Water and athletic performance: Athletes might gain a competitive edge by drinking water that contained extra dissolved oxygen. The notion stems from observations that oxygen breathing during exercise enhances athletic performance. Water is the most important element after oxygen for human life. Although human can survive for weeks without food; waterless but vitality can be maintained for a few days. The water content of the human body varies between 42-71% according to age and gender. Average 59% of adult human body is water [17].

The water loss varies from person to person during training/ race. Loss of sweat can be monitored by measuring weight immediately before and after exercise. To prevent dehydration, an athlete should drink 5-7 milliliters (mL) per kg of body mass about four hours before the start of an event [22]. Fluid drunk during exercise is necessary to replace fluids lost in sweat. In most cases, sweat loss rates are higher than drinkable during exercise, so most athletes lose fluid [27]. Compared to sports drinks, water can be replaced with sports drinks for shorter activities. Water consumption is very useful for athletes before and during training [28]. In short sports (less than 60 minutes), the best drink is cold water, it is possible to replace the lost electrolytes with nutrients during these periods [29]. Hypohydration and hyperthermia can adversely affect physiological responses to exercise and aerobic exercise performance. However, these effects can be reduced by proper fluid and electrolyte (sodium) consumption [30]. Drinking a sufficient volume of fluid during physical activity to minimize dehydration is the simplest and most effective way to maintain physiological function and improve physical performance [31]. In a dehydrated athlete, the volume of blood circulating in the body decreases.

Vitamin-Mineral and athletic performance: Micronutrients play an important role in energy production, hemoglobin synthesis, protection of bone health, adequate immune function, and protection of the body against oxidative damage. They help for the synthesis and repair of muscle tissue during exercise and recovery [32]. Careful monitoring of the micronutrient condition is also important for the prevention of inadequate fatigue and immune disorder caused by deficiency [33]. Vitamins are essential nutrients for life that provide healthy growth and development. By participating in biochemical and physiological processes in the organism; They help create energy from nutrients, normal functioning of the nervous and digestive systems, protect body health and grow. People must take most of the vitamins from outside because they cannot produce them in their own organisms [24].

Minerals are substances found naturally in the earth’s crust, and some, like vitamins, are very important for your health and can only be obtained from what you eat and drink [34]. Athletes usually do hard physical training and therefore need more energy intake and micronutrients to meet their needs. Mineral deficiency can impair athletic performance [35]. A liquid multivitamin and mineral supplement will improve athlete’s anaerobic exercise performance [8].

Nutritional supplement and athletic performance: The key to healthy and successful athletic performance is a carefully designed, healthy and nutritionally balanced diet and a welldeveloped training program. No quick fixes or shortcuts to success. In general, healthcare professionals note that vitamin supplements are not necessary for the individual for a balanced diet, but can be recommended for some people, such as the elderly, those who don’t eat meat only, and women of childbearing age [36]. In some cases, nutritional supplements may be required for athletes. For example, athletes skipping a certain food due to a food allergy or other medical problem, or athletes on lowercalorie diets may need an additional to meet the recommended daily intake. In addition, dietary supplements may be necessary to treat or prevent a known nutrient deficiency. If a vitamin / mineral supplement is required, it should be part of a total diet management plan and should be prescribed by a sports dietitian or physician [31].

Yarar et al., in his study on elite athletes; athletes use nutritional supplements to increase performance, build muscle and provide fitness. Most of the participants think that the nutritional supplements are useful [37].

Nutrition recommendations for endurance sports: The training diet is to provide nutritional support to allow the athlete to stay healthy and injury-free while maximizing the functional and metabolic adaptations to a periodized exercise program that prepares him or her to better achieve the performance demands of their event. While some nutrition strategies allow the athlete to train hard and recover quickly, others may target an enhanced training stimulus or adaptation [8]. Meeting energy needs is the main nutritional goal of endurance athletes [38]. In endurance athletes to meet the energy required for daily high and intensive training periods and to maintain the necessary muscle tissue; Carbohydrate consumption is important before, during and after training. It is important to prevent protein breakdown and maintain optimal immune function. Before the race, athletes should consume normal or high doses of carbohydrates and practice low intensity. Thus, carbohydrate oxidation capacity is not blunted on race day [39]. It shows that carbohydrate-protein intake increases the performance of multiple sprint sports over carbohydrates, potentially altered through central fatigue or increased protein oxidation [40-42].

Conclusion

Athletes need to consume energy that is adequate in amount and timing of intake during periods of high-intensity and/or long duration training to maintain health and maximize training outcomes. The training diet is to provide nutritional support to allow the athlete to stay healthy and injury-free while maximizing the functional and metabolic adaptations to a periodized exercise program that prepares him or her to better achieve the performance demands of their event. While some nutrition strategies allow the athlete to train hard and recover quickly, others may target an enhanced training stimulus or adaptation. Body carbohydrate stores provide an important fuel source for the brain and muscle during exercise and are manipulated by exercise and dietary intake. Dehydration/hypohydration can increase the perception of effort and impair exercise performance; thus, appropriate fluid intake before, during, and after exercise is important for health and optimal performance. An additional nutritional strategy for events of greater than 60 minutes duration is to consume carbohydrate according to its potential to enhance performance. vitamin and mineral supplements are unnecessary for the athlete who consumes a diet providing high energy availability from a variety of nutrient-dense foods. Athletes should be counseled regarding the appropriate use of sports foods and nutritional ergogenic aids. Such products should only be used after careful evaluation for safety, efficacy, potency and compliance with relevant antidoping codes and legal requirements [8]. Nutrition and Dietetics and Sports Nutrition affect their levels positively based on their minds. Athletes should become conscious about the importance of sports nutrition. Having sufficient level of information will also benefit in applying this information. It will be more effective and effective for the athletes to receive training from dietitians who are experts in this field to raise awareness about sports nutrition. In advanced studies, a weekly food consumption record should be kept along with the body analysis of the athletes should be compared with the nutritional knowledge levels. Athletes should be trained on basic nutritional levels. Training on nutritional needs should be provided according to the branches. From time to time, it should be determined whether the athletes are using their nutrition information correctly or not [19].

To Know More About Nutrition and Food Science International Journal 

Please click on: https://juniperpublishers.com/nfsij/index.php

For more Open Access Journals in Juniper Publishers

please click on: https://juniperpublishers.com/index.php

[juniperpublishers-nutrition]

Effects of Probiotics on Maintaining Human Health

Abstract

The purpose of this publication is to review the beneficial impact of probiotics and their role in humans’ diet. Besides, introducing the dietary sources and the role of prebiotics is included in this manuscript, as well. Pro- and prebiotics are significant also in health maintenance, they have a good influence on immunity, they decrease the occurrence of several chronic diseases, accordingly, applying them in healthy diet is not negligible either. Hopefully, my manuscript contributes to popularizing functional foods, mainly fermented products. It also meant the motivation to create this review.

Keywords: Probiotics; Prebiotics; Healthy diet; Fermentation; Functional foods

Introduction

Fermented dairy products their benefits can be found in several literature. Their beneficial impact for the organism is due to mainly the useful bacteria. Probiotics can restore the composition of gut microbiota [1], thus they help preserve the activity of the immune system [2]. Also, they serve in preventing several chronic diseases, and in supplementing the treatment. For instance, they are applied in cosmetics industry, pharmaceutical industry, feed industry and food industry; their outstanding representatives are Lactobacilli and Bifidobacteria. In my manuscript their effect on human organism are reviewed, and those possibilities are revealed which may be the part of everyday diet. I believe it is essential to highlight the role of both pre- and probiotics in humans’ diet, how they contribute to maintaining healthy lifestyle.

Role of prebiotics in humans’ diet

Prebiotics are non-digestible oligosaccharides (e.g. inulin, fructo oligosaccharides), which help the probiotics with colonization, prevent the establishment of pathogens, and help the production of short-chain fatty acid. Besides, they are also the nutrition of probiotics. In some cases, they are complemented by means of food supplement, so they appear as symbiotic, where there are pre- and probiotics together [3]. Their primary dietary sources are the nutrition with high fibre contents, mainly vegetables and fruit (e.g. oat flakes, apples, plain chocolate, walnut), that also induce increase in beneficial intestinal bacteria [4].

Beneficial effects and dietary sources of probiotics

It is worth to get to know the proper diet, namely those of consuming probiotics, in childhood. Then, as part of getting to know the healthy diet, foods containing probiotics [5], mainly fermented dairy products are also promoted. Beneficial bacteria have a role principally in establishing gut microbiota. They prevent the colonization of pathogens, ensure the integrity of permeability, control bowel motility [6], and help the immune system with normal function, and thus with maintaining the intact gut microbiota, as well. Beside aiding the digestion, several literatures is about probiotics used in cosmetics industry, which have a role in protecting the skin and maintaining its health [7]. Moreover, they produce antimicrobial agents and influence metabolic pathways, also they reduce the risk of cancer [8]. Among dietary sources fermented foods (yoghurt, kephir, leavened bread) outstand [9]. Probiotic content of functional foods can be increased with enrichment, as well.

Conclusion

The most important purpose of my manuscript is to review the beneficial impacts of probiotics, their role in human organism, and to give dietary advice, that can help to consume more in everyday diet. I believe it is essential to highlight the importance of prebiotics and their dietary adaptability that also contributes to maintain the gut microbiota. I am convinced and several literatures proves that dietary adaptation of pre- and probiotics has a significant role in preventing and treating digestive disorders. I hope, my manuscript contributes to popularizing agents used also as part of healthy diet.

To Know More About Nutrition and Food Science International Journal 

Please click on: https://juniperpublishers.com/nfsij/index.php

For more Open Access Journals in Juniper Publishers

please click on: https://juniperpublishers.com/index.php

[juniperpublishers-nutrition]

Assessment of Water requirements for Horticultural Crops in Arid Regions

Abstract

Arid regions have very low precipitation values (usually less than 250mm), consequently there is little water availability, so in these regions efficient management of this resource is imperative. This study aims to assess the water needs of some horticultural crops and a fruit tree on the island of São Nicolau, Cape Verde. Twelve crops were selected among the most used by farmers in the area and three scenarios related to precipitation were created. The water needs of the crops in the three scenarios were assessed using the previously calibrated Hargreaves - Samani method. The water balance to determine irrigation consumption was made for the following 3 rainfall conditions: scenario 1 corresponds to the year with the lowest rainfall; scenario 2 is the average of the values recorded over the series; and scenario 3, the year with the highest rainfall. The consumption of water by the crops was not significantly different in the 3 scenarios, the difference being in the amount of water resulting from the precipitation that can be stored and, thus, determining which area can be dedicated to irrigated agriculture. The lettuce, cucumber, pepper and carrot cultures, since the cultures studied were those with the lowest water requirements. The cultivation of banana cultivation should be the subject of a study on its adaptability, due to its high consumption, namely the possibility of applying deficient irrigation in order to increase water productivity.

Keywords: Arid regions; Water needs; Horticultural crops

Introduction

Arid climatic zones can be defined, according to [1], as those in which in no season of the year can crops grow without the use of irrigation, where, normally, the average annual precipitation is less than 250 mm and with a very irregular, unpredictable fall and with wide intervals.

In these regions, which normally have very high evaporation rates, as well as very high solar radiation values and very low air humidity, a very intensive type of agriculture could develop. However, normally, its low resources in surface or ground water prevent this from happening [2].

The need for water in a crop corresponds to the evaporative demand for that crop in a given environment and receiving specific cultural treatments. Crop evapotranspiration is the sum of crop transpiration and soil water evaporation. There are several methods that can be used to calculate the reference evapotranspiration, among which Penman-Monteith [3] stands out.

With this method, it is possible to obtain results similar to those observed in the measurement of grass cover evapotranspiration, as it has a solid physical base and for clearly incorporating both physiological and aerodynamic parameters. The grass was chosen as a reference crop, with a constant height and also a constant surface resistance, in order to avoid the problems of local calibration, which require exhaustive and expensive studies [3].

In many regions, in particular in Africa, there are no consistent climatic data and, often, only maximum and minimum temperatures are obtained. Under these conditions, it is not possible to use the Penman-Monteith method, so more simplified ones should be used, such as the Hargreaves-Samani method. This method is widely used for irrigation management in situations with little available meteorological data [4]. According to Shahidian et. al, [5]. The Hargreaves-Samani equation has been used a lot by other authors and in several regions and with good results namely:

a) Sepahskhah and Razzaghi (2009) where they used lysimeters to compare the Thornthwaithe, Willmott and Hargreaves- Samani equations in the regions semiarid regions of Iran and concluded that the calibrated Hargreaves-Samani equation was the most accurate.

b) Lopes Urra et al. (2006), compared seven ET0 equations in the arid region of southern Spain with data from lysimeters and concluded that Hargreaves Samani was the second best after the Penman Montheith equation.

c) (Martínez-Cob and Tejero-Juste, 2004, Jensen et al., 1997), and as the Hargreaves equation does not account for the wind, it differs significantly from calculations performed with the Penman-Monteith equation. As the wind speed in the greenhouse is negligible, it is likely that these equations can produce more satisfactory results inside greenhouses than outside.

The present work uses the Hargreaves-Samani method for the hydrographic basin of Fajã, in the municipality of Ribeira Brava, on the island of São Nicolau, in Cape Verde.

Methodology

The island of São Nicolau is located between the parallels 16ᵒ 30 ‘and 16ᵒ 40’ N and the meridians 24ᵒ and 24ᵒ 30 ‘W. The NW is the island of Santa Luzia and the N-NE is the island of Sal. fifth island of the archipelago in surface, occupying an area of 343 km2 with a maximum length of 45 km in the EW direction and a maximum width of about 25 km in the NS direction (Nunes, 1962a).

The Fajã River Basin is located in the municipality of Ribeira Brava and is one of the most important basins on the island of São Nicolau, extending from the Monte Gordo massif to the seafront, covering an area of 13.8 km², as shown shown in Figure 1.

For the development of this study, the first selection of agricultural crops usually practiced by farmers in the Fajã area was carried out.

Within the range available, 12 representative crops were chosen, and which were considered most suitable for the economic sustainability of farmers in the irrigation perimeter. Eleven vegetables were selected, which are: onion, carrot, lettuce, cucumber, tomato, watermelon, sweet potato, pepper, beet, common potato and cabbage and a fruit tree, banana.

The assessment of the water needs of the crops was carried out based on the calculation of the reference evapotranspiration, for the average year, using the Hargreaves-Samani method, with the maximum temperature and minimum monthly temperature data for the Preguiça aerodrome station, for the period from 1941 to 1960 (19 years). These data were taken from the study and project to use the areas of influence of the new dams in Cape Verde, as there are no other data available [6].

The Hargreaves-Samani method was previously calibrated for the Cape Verde situations, based on the climate data of the island of Santiago, obtained from the PhD dissertation by Moreno [7].

In 1985 Hargreaves and Samani developed a simple equation that only needs air temperature data (minimum highs), and the latitude-dependent coefficients of the place and time of year. This equation, known as the Hargreaves-Samani equation, is described by the following expression:

In which:

ET0 = Reference evapotranspiration (mm / day)

Ra = radiation at the top of the atmosphere (mm / day)

Tmax = maximum temperature (ᵒC)

Tmin = Minimum temperature (ᵒC)

Krs is the equivalent unit of water evaporation, varying between 0.19 in coastal areas and 0.16 in inland areas. Usually the equation is written with Krs equal to 0.17

For this calibration, the reference evapotranspiration was calculated by the Penman-Monteith method and by the Hargreaves-Samani method, to then draw a calibration line that allows to adjust the results obtained by this last method. This line is described by the following equation:

Y = 1,4615x - 0,7662, com R2 = 0,99

Since Y, the result obtained by the Penman Montheith method and x, the result obtained by the Hargreaves-Samani method, the adjustment of the calibration line can be seen in Figure 2.

Cultural evapotranspiration (ETC) was obtained using the following formula ETC = ET0 * Kc where,

(ET0) is reference evapotranspiration

(Kc) the cultural coefficient

The values of the cultural coefficients used were obtained using the specialized bibliography. The Kc values and the respective references can be found in Table 1.

Irrigation needs were calculated using the water balance method as described in [8], with three precipitation scenarios having been created, since in Cape Verde, rainfall varies greatly from year to year [9-11].

The balance was made for the following three rainfall conditions: scenario 1 corresponds to the year with the lowest rainfall; scenario 2 is the average of the values recorded over the series; and scenario 3, the year with the highest rainfall. Table 2 shows the precipitation values for the 3 scenarios.

Results and discussion

The Hargreaves-Samani method underestimated the reference evapotranspiration values by 15-18% compared to the values obtained by the Penman-Monteith method.

The average annual reference evapotranspiration is 1737.6 mm. There is a certain difference from month to month, especially between the months of December and September, the difference between these two months being 102 mm. December was the lowest (96 mm) and September the highest (198 mm). If this difference is not taken into account, this fact can be problematic in terms of irrigated agriculture for an arid region in dry years, especially with regard to the availability of water to satisfy the water needs of the crop.

In other years, the high evaporative rate coincides with the months of greatest precipitation. Table 3 shows the average monthly values of reference evapotranspiration and cultural evapotranspiration for the cultures considered in this study.

In Figure 2, it can be seen that the banana crop is the one with the highest irrigation consumption, about 1100 mm over its cycle, which represents 57.6% of the annual reference evapotranspiration on the island of São Nicolau.

The crops with the least watering consumption are lettuce, peppers, carrots, cucumbers and cabbage. This aspect must be taken into account when choosing the crop, especially in cases where there is little availability of water for irrigation. On the other hand, the banana culture, being the crop that presents the highest consumption of irrigation, in situations of water scarcity should give way to other cultures that are less demanding in water, with the aim of a more sustainable management of water resources.

The irrigation needs and the respective amount must be taken into account when choosing the crops and the area to be devoted to each of these crops, especially in years with little water availability. On the other hand, from the market point of view, in which the price is often not competitive, especially for those who use surface irrigation, as the demand for water is greater in relation to that of drip irrigation. In scenario 2, despite presenting greater precipitation compared to scenario 1, with a difference of 199.4 mm, there is not much difference (27.9 mm) in terms of water consumption.

Regarding the irrigation needs for the selected crops, there are differences in terms of the monthly irrigation needs. The biggest difference is observed in the lettuce culture, without significant distinction between scenarios (which also happens with peppers) and with watering needs about five times lower than those of bananas and three times lower than those of onions as you can see in the Figure 3.

Evolution of irrigation consumption throughout the year

The months with the highest consumption of water for irrigation are the months of January and May, with around 1000 mm, with no difference for the 3 scenarios in the month of January (Figure 4). The same is no longer the case with the month of May, where the lowest consumption of irrigation water is recorded in scenario 2, with a consumption of 103.5 mm, as a result of a better distribution of rainfall throughout the year.

In the period from July to October there is practically no water consumption, particularly for scenarios 2 and 3. (Figure 4)

The evolution of water consumption by irrigation and the water needs of the crops throughout the year is very important information to adapt the crop calendar, so as not to install a water demanding crop in periods when there is a greater demand for water. water by the others, thus compromising the management of water resources.

Conclusion

Access to climatic data for the calculation of evapotranspiration in Cape Verde, and in particular on the island of São Nicolau, is still limited because, in addition to the lack of weather stations, the few stations that exist operate in a deficient manner.

The evolution of water consumption by irrigation and the water needs of the crops throughout the year is very important information to adapt the crop calendar, so as not to install a water demanding crop in periods when there is a greater demand for water. water by the others, thus compromising the management of water resources.

In the irrigation perimeter of the Banca Furada dam, it can be seen that there will be two periods of the year with a greater number of crops on the ground and, consequently, greater area for irrigation and greater water consumption: from November to February and from March to June.

For some crops, namely the banana crop, higher water consumption was obtained in scenario 3 (the year with the highest rainfall) than in other scenarios, contrary to what was expected. This is due to the fact that the months of August, September and October present high values of precipitation, that is, great availability of water.

The consumption of water by the cultures was not significantly different in the 3 scenarios, the difference being the amount of water resulting from precipitation that can be stored and, thus, determining which area can be dedicated to irrigated agriculture.

The lettuce, cucumber, pepper and carrot cultures, since the cultures studied were those with the lowest water requirements.

The cultivation of banana cultivation in years with little rainfall should be the subject of a study on its adaptability, due to its high consumption, namely, the possibility of the application of deficient irrigation in order to increase the productivity of the water used in this culture.

To Know More About Nutrition and Food Science International Journal 

Please click on: https://juniperpublishers.com/nfsij/index.php

For more Open Access Journals in Juniper Publishers

please click on: https://juniperpublishers.com/index.php

[juniperpublishers-nutrition]

Ketogenic Diet: Biochemistry, Weight Loss and Clinical Applications

Chemistry of food and its biochemical interactions

Abstract

The ketogenic diet (KD) has obtained immense popularity that stretches beyond its myriad of clinical applications. KD provides a practical solution to attain body recompositing and meet the weight loss target within a short interval. This review aims to eliminate misinformation surrounding the KD as it has now become a fad diet. All the major scientific evidence revolving around the biochemistry, physiology, and weight loss are compiled. A special section is dedicated to the scientific literature published on the usage of KD in the management of diabetes and neurological diseases such as drug-resistant epilepsy, Alzheimer’s disease, and Parkinson’s disease. Lastly, the short-term and long-term adverse effects with the use of KD are discussed and cautionary contraindications are also listed.

Keywords: Nutritional ketosis; Obesity; Ketogenic diet; Ketogenesis; Weight loss; Epilepsy; Diabetes; Neurological

Introduction

Obesity has a complex multivariate etiology, but it can be managed via lifestyle modifications and dietary alterations. Interestingly, it has always remained in the background as a modifiable factor modulating the mortality and morbidity in a myriad of medical conditions such as diabetes, cardiovascular and peripheral vascular disease, and hypertension. As such, obesity contributes to the staggeringly high adult mortality rate of 2.8 million per year.

The global trend is alarming as the prediction model still seems to be favoring the positive increasing trends. The WHO statistics in 2016 reported that over 1.9 billion and 650 million adults were overweight and obese, respectively. These obesity prevalence projections remain consistent at local levels and in all age cohorts. Ward et al. fitted a multinomial regressions model that has predicted that by 2030, 48.9% of adults in the US will be obese [1]. The pediatrics cohort has also now joined this predicament. In the UK, the epidemiological data provided by the National Child Measurement Program showed an increase of 0.7% in 4 years within the 10-11-year-old cohort with a baseline obesity prevalence of 20% [2]. Specialized dietary alteration for weight loss can be effective in preventing the rampant rise in obesity. The ketogenic diet consisting of very low caloric contribution by carbohydrates and calorically predominant fat contribution has shown effective and sustainable acute weight loss [3-5].

Review

Utilization of the ketogenic diet

The composite macromolecules are stratified as 55-60% from fats, 30-35% proteins, and 5-10% carbohydrates. This would translate as a person with a baseline 2000kcal intake will require 133.3 g of fat, 175g of proteins, and 25g of carbohydrates.

History of ketogenic diet

Woodyatt et al. reported the production of ketone bodies such as acetone, acetoacetate, and β-hydroxybutyrate in healthy subjects when starved or put on a low-carbohydrate and high-fat diet [6]. Dr. Russel Wilder coined the term ketogenic diet in 1921 and proposed that this diet could be used to treat epilepsy. In the following decade, the ketogenic diet had become standard for the treatment of pediatric epilepsy until the advent of antiepileptics [7-9].

Biochemistry and physiology of ketogenic diet

Stringent carbohydrate restriction below 50g leads to insulin suppression which causes a global catabolic state. After the glycogen reserves are depleted the compensatory metabolic processes gluconeogenesis and ketogenesis occur [10,11]. Gluconeogenesis utilizes lactic acid, glycerol, and glucogenic amino acids as substrates for endogenous glucose synthesis. During prolonged starvation, this constitutional production of endogenous glucose will be outpaced by the metabolic demands of the body. An alternative energy source in the form of ketone bodies via ketogenesis will now become the primary energy source. Due to the low serum glucose levels, insulin secretion is drastically decreased and therefore halts fat and glucose storage. The ketogenesis enzymes are upregulated and hence increase the triacylglycerol catabolism. The resultant fatty acids are broken down into ketones bodies (acetone, acetoacetate, and β-hydroxybutyrate). If the low carbohydrate and high fat state are maintained ketosis will perpetuate. This ketosis state is called nutritional ketosis wherein the serum ketones concentration is within 0.5-3.0mmol/L and there is a compensatory mechanism to maintain the blood pH in the physiologic range (7.35-.45). In the absence of compensation, the serum ketone concentration is >10mmol/L. This can manifest as ketoacidosis or the rare alkaline ketoacidosis (masked DKA).

Endogenous ketone bodies are utilized by the kidneys, cardiac and skeletal muscles, and the neural tissues via the blood-brain barrier. RBCs have no mitochondria and hepatocytes lack the enzyme beta ketoacyl-CoA transferase in its mitochondrial matrix and therefore the only tissues that are unable to utilize ketones. The rate of production of ketones can vary based on the basal metabolic rate, age, and body fat percentage. Interestingly, the utilization of ketones leads to a reduction in the production of reactive oxygen species. The epigenetic modulation is targeted via specific inhibition of the class I histone deacetylases by β-hydroxybutyrate [12]. This causes downregulation in the transcripts of genes FOXO3A and MT2, responsible for oxidative stress resistance [12].

Ketone bodies are more efficient energy production substrates than glucose or fatty acids. Each unit of fatty acids, ketones, and glucose produce 6.7, 5.4, and 5.4 ATPs, respectively [13]. Energy efficiency is better expressed as ATP per oxygen atom ratio (P/O ratio). The P/O ratio for glucose, ketone, and fatty acids is 2.58, 2.50, and 2.33, respectively [13]. There is a need for novel experiments that measure the effect of ketones on cardiomyocytes and skeletal tissue preparation to discern the mechanical work to oxygen output ratio in both physiological and pathological states.

Ketogenic diet for weight loss

Table 1 [14-22] displays the weight changes over multiple studies comparing weight loss in ketogenic diets and low-fat diets at six and twelve months. An average of 5 studies containing 663 patients was completed for 6 months comparing ketogenic diet weight loss and low-fat diet weight loss. The results present a greater weight loss by a ketogenic diet (9.6Kg) compared to weight loss using low-fat diets (5.8Kg). Importantly, when these dietary plans were carried out for 12 months with an average of 910 patients; there was a much lower difference between the weight loss in the ketogenic diet (5.7Kg) compared to a low-fat diet (4.6Kg). Thus, the conclusion is both diets are beneficial for weight loss; however, ketogenic diets may be more beneficial in the first 6 months compared to low-fat diets. Another metaanalysis of multiple randomized controlled trials at 12 months or longer was carried out comparing a very-low-calorie ketogenic diet (VLCKD) with low-fat diets. The VLCKD group recorded more weight loss over 12 months (average weight difference, -0.91kg; 95% CI: -1.65 to -0.17, in 1415 patients) [22].

Temporal association of weight loss during ketogenic diet

The rapid decrease in weight in the first 2 weeks following a ketogenic diet is often misunderstood as a fat loss when the majority is water loss. This occurs because carbohydrate polymers quench water molecules when stored in the body, and thus low carbohydrate diets cause a diuretic effect in the initial weeks. This water weight can come back rapidly if people begin to consume carbohydrates again.

Physical exam and laboratory changes during the ketogenic diet

The effects of ketogenic diets vs low-fat diets were examined in a meta-analysis of 23 randomized controlled trials with 2788 participants. The results display that in comparison to low-fat diets, a VLCKD diet recorded lower systolic and diastolic blood pressure, decreased serum triglyceride levels (-14.0mg/dL; 95% CI: -19.4, -8.7), and elevated HDL levels (3.3mg/dL; 95% CI: 1.9, 4.7). However, a VLCKD diet causes an increased net difference of LDL cholesterol levels in participants (+3.7mg/dL; 95% CI: 1.0, 6.4) [23]. The data supports the conclusion that a reduction of carbohydrates in diets such as the VLCKD diet is adequate for weight loss; however, it is associated with increased total cholesterol levels and the VLCKD diet has not been proven to be clearly more effective than other weight loss methods. In addition, there were no significant differences between VLCKD diets or low-fat diets in the reduction in weight or waist circumference. Finally, it is important to note that this study did not assess the serum ketone levels, thus it is undetermined whether the weight loss is associated with ketosis or any ketogenic effects.

Monitoring ketones

Urine strip is useful to detect ketones during the early phase of nutritional ketosis. Later, there will be a renal adaptation wherein the ketones are reabsorbed, and the urine dipstick will not be sensitive enough [24]. More accurate monitoring is by handheld glucometer (precision Xtra®, Abbott) that has a ketone modality to detect β-hydroxybutyrate. These devices measure blood glucose and ketone levels. In a comparison between urine dipstick and handheld β-hydroxybutyrate testing, a total of 516 hyperglycemic patients were used. The urine dipstick had a sensitivity and specificity of 98.1% and 35.1% respectively. When using handheld testing devices following a cutoff of >1.5mmol/L, the sensitivity and specificity were 98.1% and 78.6% respectively. The inference from these results can be drawn that both urine dipstick and handheld devices both have a high sensitivity for ketones; however, the handheld β-hydroxybutyrate detecting devices have a much higher specificity for ketones, which is important in the case of diabetic patients where this may significantly reduce the number of diabetic patients that enter the emergency department [25].

The breath test has a good correlation with blood β-hydroxybutyrate levels (r=0.821) as well as blood acetone levels. When the concentration of blood β-hydroxybutyrate served as the standard, the sensitivity of exhaled acetone was 90.9% with a specificity of 77.1% [26]. Breath tests have a high sensitivity and specificity, thus making them beneficial as a non-invasive and convenient method of measuring ketones. Importantly in rare situations, people may have false-positive results with an alcohol breath test due to ketogenic diets because of ketonemia. This occurs due to acetone being reduced to isopropanol by hepatic alcohol dehydrogenase in the body, thus giving a false-positive result on alcohol breath tests if inexpensive models are in use.

Clinical Implication

Ketogenic diets can be used in managing a myriad of Neurological disorders, Diabetes, Pre-Diabetes, Cancer, Polycystic Ovarian Syndrome, and Autosomal Dominant Polycystic Kidney Disease.

Ketogenic diet in neurology

While modern pharmaceutical drugs are the first-line treatment for epilepsy, there has been a resurgence of the keto diet as a treatment option for drug-resistant epilepsy. The quality of life of patients with drug-resistant epilepsy is often severely negatively impacted, ultimately urging them to try every treatment available for this debilitating illness. The mechanism behind the therapeutic effect of the keto diet in treating epilepsy has been studied extensively on animal models in vivo and in patients with epilepsy in a clinical setting. Kawamura et al. performed a study on mouse and rat models of epilepsy to understand the effect of glucose levels on hippocampal neuronal excitability [27]. In vitro analysis of brain slices of animals that were fed a keto diet for 2-3 weeks showed reduced neuronal excitability, specifically in the seizure-prone region of the hippocampus CA3 [27]. Furthermore, the binding of adenosine to the adenosine A1 receptor (A1R) leads to an inhibitory effect that decreases neuronal excitability. The keto diet increases adenosine levels, which is one possible mechanism for seizure prevention. Kawamura et al. fed A1R knockout animals the keto diet, in which it no longer reduced neuronal excitability in vitro. This study demonstrated the significance of a low glucose diet in reducing neuronal excitability in a seizure-prone area in the brain and a possible physiological mechanism underlying the effect of the keto diet in treating epilepsy.

Patients on a keto diet have less glucose available to be metabolized by the brain for energy, ultimately leading to the utilization of ketone bodies as an alternative energy source. Ketone bodies are metabolized anaerobically, decreasing the energy available and leading to a higher seizure threshold [28]. The Modified Atkins Diet (MAD) is a modified version of the ketogenic diet that has more flexibility and palatability. This renders it better suited for children compared to the ketogenic diet especially since both diets have an equivalent therapeutic value for treating children with drug-resistant epilepsy [29]. There is also evidence for the efficacy of MAD in treating drugresistant epilepsy in adolescents and adults, however, the rate of seizure reduction is lower than that of the children population [28].

There is further evidence for the efficacy of the keto diet in treating other neurological diseases such as Alzheimer’s disease (AD) and Parkinson’s disease (PD) [30]. In a study carried out by Henderson et al., patients with AD were given a medium-chain triglycerides drink (MCT) for 3 months and compared them with AD patients that received a placebo drink. Patients that received an MCT drink scored significantly higher on the Alzheimer’s Disease Assessment Scale. Another study examined the efficacy of the keto diet in treating patients with PD [31]. It was found that patients treated with the keto diet for 4 weeks showed an improvement in their score on the Unified Parkinson’s Disease Rating Scale. Additionally, there is evidence for the efficacy of the ketogenic diet in rat models for the treatment of brain cancer, neurotrauma, and amyotrophic lateral sclerosis [30]. The results of these studies on in vivo animal models provide a steppingstone for further research on the efficacy of the keto diet in treating other neurological disorders, which can be worthwhile in patients where pharmaceuticals are proven minimally effective.

Ketogenic diet in type 2 diabetes mellitus (T2DM)

T2DM patients (n=13) were treated with 2 diets for a duration of 3 weeks. The diet was matched for a caloric intake of 650kcal and protein intake, but one group received low carbohydrates (24g) and the other received high carbohydrates (94g). The low carbohydrate group entered nutritional ketosis confirmed by their serum β-hydroxybutyrate levels [32]. This group had lower fasting glucose levels and Oral Glucose tolerance test (OGGT) glycemia and 22% lower hepatic glucose output (HGO) [32]. This study validates that serum ketone levels have a strong correlation with HGO.

T2D inpatients (n=10) fed on a low carbohydrate (<20g) diet for 2 weeks had a 1.2mmol/L drop in serum glucose drop from a baseline admission glucose of 7.5 mmol/L [33]. A significant improvement in insulin sensitivity shown by 75% in the euglycemic hyperinsulinemic clamp [33]. The hemoglobin A1c dropped 0.5% from a baseline admission reading of 7.3% [33]. The hemoglobin A1c is representative of chronic hyperglycemia over the life span of an RBC (120 days), as such this result must not be given significant weightage. With further investigation, it is seen that a diet with less than 45% carbohydrates that one would have further glycemic control. With the trials investigated following the KD, as the number of restriction increases (like the data point where there are 20% carbohydrates that make up your diet there is a -23% change in HbA1C whereas if there is a greater amount of carbohydrates to approximately 54% there is an increase of +12.5% increasing the amount of HbA1C). More than half of the patients participating in the study using the ketogenic diet in the study had a change in their HbA1C.

Adverse Effects of the Ketogenic Diet

Initiating the ketogenic diet leads to natriuresis in lieu of the low circulating insulin levels. This leads to loss of circulating volume and can manifest as headaches, orthostatic hypotension, fatigue, compensatory tachycardia. If the sodium is not replaced, then the Renin Angiotensin Aldosterone System (RAAS) cycle can induce hypokalemia and its resultant sequelae. Long-term usage of the ketogenic diet can cause hepatic steatosis, hypoproteinemia, and vitamin and mineral deficiencies. Importantly, urolithiasis can issue secondary to urine acidification.

Pediatric patients on the ketogenic diet can experience constipation, low-grade acidosis, and hypoglycemia. More rare side effects in these children are kidney stones, dyslipidemia, and diminished growth. The acidosis and the hypercalcemia in the diet are the causes of the stones, and these children tend to have a low baseline acidosis, with HCO3 between 12- and 18 mg/dL. To be more aware, continual screening for stones and potassium bicarbonate is given with a dosage of 2mEq/Kg/Day split within the day as a ratio higher than 0.2. Without evidence of a family history of kidney stones, certain anticonvulsants with carbonic anhydrase inhibition properties that increase the risk of kidney stones should be avoided. None of these however tend to be the reason behind the discontinuation of the keto diet, it is usually due to its inefficiency as a diet (around 3-6 months is the usual time span) that is helping the children with epilepsy.

Contraindication

The ketogenic diet has a relative contraindication in diabetics on insulin or oral hypoglycemics as they need careful optimization of their regiment prior to initiation of this diet. The ketogenic diet has an absolute contraindication in pancreatitis, hepatic failure, congenital fat metabolism errors, porphyrias, and pyruvate kinase deficiency.

Conclusion

The ketogenic diet has been implemented in the management of a myriad of neurological diseases, diabetes, cancers etc. This diet has now been revived beyond its clinical application since KD mirrors the metabolic pathways identified in caloric restriction and longevity. This might make it appealing to the fad culture of dieting, but the short-term benefits must be weighed against the long-term adverse effects and contraindications. KD has shown to cause rapid weight loss of up to 9.6kg within 6 months. Physiological changes associated with the VLCKD include hypotension, and an elevated HDL and LDL. People attempting KD can accurately monitor their ketone levels to verify nutritional ketosis using the handheld glucometer and the ketone breath test. During this COVID-19 period, the ketogenic diet has become a popular and practical solution for rapid weight loss in lieu of the constraints for physical exercise amidst the quarantine.

To Know More About Nutrition and Food Science International Journal 

Please click on: https://juniperpublishers.com/nfsij/index.php

For more Open Access Journals in Juniper Publishers

please click on: https://juniperpublishers.com/index.php

[juniperpublishers-nutrition]

Antiproliferative Effect of Green Papaya on Lymphocytic Leukemic Cells

Abstract

Numerous edible plants have been reported to interfere with the carcinogenic process, and therefore, the regular consumption of these plant products may reduce the risk of developing cancer. We investigated the effect of papaya fruit and leaves on the cell proliferation of Jurkat T-lymphocytic and Daudi B-lymphocytic leukemia cells. Cells were treated with aqueous or methanolic extracts from leaves, skin, pulp, and seeds from green papaya. The papaya fractions were tested for total phenolic content, total flavonoids content, and anti-oxidation activity using chemical assays. Cell proliferation was measured using a WST-1 assay. Our data indicate that methanol and water extracts of seeds and leaves contained higher concentrations of total phenolic compounds and higher anti-oxidation activity than that of extracts from skin and pulp.

Both methanol and water extracts from leaves and skin potently inhibited the proliferation of leukemic Jurkat T-cells and Daudi B-cells. However, the effect was more potent on Jurkat T-cells, and the leaf extracts were more effective than that of skin extracts. None of the pulp or seed extracts showed inhibitory activity on leukemic cell proliferation. Although papaya leaves are not consumed as a food, leaf extracts have been used for the treatment of various conditions, including dengue and malaria fevers, gastric ulcers, low platelet counts, and cancers of the breast, lung, and cervix. Our data suggest that the consumption of papaya leaf extracts may also be beneficial in preventing and/or treating lymphocytic cancer. Isolation of active compounds from papaya leaves will also help in developing new drugs for cancer treatment.

Keywords: Polyphenols; Antioxidants; Anticancer; Jurkat cells; Daudi cells; Leukemia

Introduction

Leukemia is a cancer of the blood or bone marrow, as described by an anomalous multiplication of immature clonal hematopoietic cells. Leukemia is one of the cancers that can affect all races in the United States. The American Cancer Society estimates that there will be around 60,530 new cases of leukemia in the United States in 2020, resulting in 23,100 deaths [1]. Leukemia is classified based on its onset (acute or chronic), the affected blood cell type (lymphoblastic/lymphocytic or myeloid/myelogenous), the maturity stage of the blood cell, and phenotypic expression of the disease [2]. Leukemia, like other forms of cancer, can be treated by using a number of methods, including chemotherapy, radiation therapy, targeted therapy, or stem cell therapy, though it is easier to treat acute leukemia than chronic leukemia [3]. Although leukemia remains a common medical issue, there has been a decrease in incidence due to preventive measures, and death rates have also declined since 1991 due to recent advances in treatment strategies [4]. The 5-year survival rate for children with acute lymphocytic leukemia has greatly increased over time to about 90% [5]. Although there are improved treatment strategies and survival rates, the cost of such therapies remains an issue that hinders access for all patients [6]. There is a need for less expensive alternative strategies to increase treatment access and survival outcomes for all patients.

Recent advances in alternative and complementary medicine have shown that various herbs, fruits, and vegetables have compounds that could act as inhibitors of cancer formation, blockers of carcinogen interaction, and suppressors of tumor progression. For example, Korean red ginseng extract treatment inhibited the growth of U937 leukemia cells by downregulating the expression of human telomerase reverse transcriptase [7]. Another study confirmed that Kenaf seed oil causes the death of human leukemia cells HL60 and K562 by induction of apoptosis [8]. Studies demonstrated that a hot water extract of Euphorbia formosana (EFW) restrained the growth of THP-1 human leukemic cells by inducing apoptosis through caspase-dependent cell death via Fas and mitochondrial pathways [9]. Water, ethanol, and methanol extracts of garlic have exhibited lethal cytotoxic effects of 50-75% on cells harvested from 3 patients with acute lymphoblastic leukemia (ALL) and three patients with acute myeloid leukemia (AML) [10]. Typhonium flagelliforme (TF), a herbal plant in Malaysia, exhibited cytotoxic effects in P388 [11] and WEHI-3 [12] murine leukemia cells. Further, in vivo studies showed a significant decline in the cell count of immature monocytes and immature granulocytes, when the TF extract was orally administered for 28 days in a BALB/c leukemic mouse model [12]. Studies with grape seed extracts reported induction of apoptosis in Jurkat leukemic cells through a process that involves sustained JNK activation and Cip1/p21 up-regulation, culminating in caspase activation [13].

Papaya fruit has also been studied for its anticancer activities for colorectal [14], prostate [15,16], cervical [17], breast [18- 20], and skin cancers [21]. Papaya also effectively inhibits cancers of hematopoietic cell lines, including T cell lymphoma (Jurkat), plasma cell leukemia (ARH77), Burkitt’s lymphoma (Raji), anaplastic large cell lymphoma (Karpas-299), and human promyelocytic leukemia (HL-60) [22-23]. A study demonstrated that Benzyl isothiocyanate (BITC), a promising chemo preventive agent found in papaya fruits, when given followed by cisplatin (BITC/cisplatin) caused significant death in HL-60 cells [24]. Furthermore, a recent study reported that papaya leaf extract improved bone marrow blast counts and stabilized the hematological parameters of a 76-year-old male with untreated chronic myelomonocytic leukemia [25].

It is well Known that fruits, vegetables, and other medicinal plants contain polyphenols and flavonoids that exhibit various biological and pharmacological properties [26], which are often mediated by their anti-oxidation activity [27]. Based on these earlier studies, we evaluated water and methanol extracts from leaves, skin, pulp, and seeds of green papaya on T-lymphocytic leukemia and B-cell lymphocytic leukemia using Jurakt and Daudi cell lines, respectively, and hypothesized that the effect of papaya fractions on cell proliferation of leukemic cells is correlated to their phenolic contents and/or anti-oxidation activity.

Materials and Methods

Materials

The Jurkat T-cell line and Daudi B-cell line were purchased from ATCC (Manassas, VA). RPMI 1640 medium was purchased from Gibco (Grand Island, NY). Fetal Bovine Serum (FBS) was purchased from RAMBIO (Missoula, MT). Penicillin and streptomycin antibiotics (BP2959) and Phosphate Buffered Saline (PBS; BP399-550) were purchased from Fisher Scientific (Fair Ln, NJ). Folin Ciocalteu, sodium carbonate, aluminum chloride, Diphenyl-1-picrylhydrazyl (DPPH), quercetin, gallic acid, and trolox were purchased from Sigma Chemical Co. (St Louis, MO). WST-1 (MK400) was purchased from Takara (Kusatsu, Shiga, Japan). Green papaya was obtained from Randolph Farm at Virginia State University, Petersburg, VA.

Isolation of papaya leaves, skin, pulp, and seeds

The papaya samples were isolated as described previously [28]. Briefly, the papaya was washed with distilled water and blotted dry with a paper towel. The skin was peeled off using a kitchen peeler. An unskinned papaya was cut into half to remove seeds, and then the pulp was cut into small pieces. The leaves and seeds were washed with distilled water. All fractions (leaves, skin, pulp, and seeds) were freeze-dried. The dried leaves, skin, pulp, and seeds were ground to a fine powder using a mortar and pestle with liquid nitrogen added to keep the powder frozen. The dried powder was flash-frozen with liquid nitrogen and stored at -80 ℃ until used.

Preparation of extracts from papaya leaves, skin, pulp and seeds

The methanol and water extracts of papaya fractions were prepared as described previously [28]. Briefly, a known quantity (5g) of different fractions of freeze-dried papaya powder was homogenized with 200ml of 80% methanol or distilled water. The mixtures were placed on a shaker at room temperature overnight. The next day, the mixture was centrifuged at 2000 x g for 20 minutes using a Thermo Scientific centrifuge (Waltham, MA). The supernatants were collected, and the residues were washed two times by resuspending in the respective solutions, mixing, and placing on a shaker overnight. The collected supernatants were pooled, and the insoluble residues were discarded. The methanol extracts were dried in a nitrogen evaporator (Organomation Associates, Inc, Berlin, MA), whereas the water extract was freezedried. The dried extracts were stored in a -20℃ freezer. The dried extract was suspended into DMSO at a concentration of 250mg/ ml and was further diluted into media for cellular studies.

Characterization of anti-oxidation activity of papaya extracts

The oxidative properties of papaya were determined by assaying their total polyphenolic content (TPC), total flavonoid content (TFC), and anti-oxidation capacity (DPPH) as previously described [29].

Cell culture

Jurkat T-cells and Daudi B-cells were maintained in RPMI 1640 media supplemented with penicillin (100 units/ml), streptomycin (100μg/ml) and 10% FBS. All cell cultures were incubated in a humidified incubator at 37 °C and 5% CO2. Media was changed every three days, and cells were subcultured when they became confluent.

Cell proliferation assay

The effects of papaya leaf, skin, pulp, and seed extracts on cell proliferation were determined using a WST-1 assay as per manufacturer instructions and described previously [28]. Briefly, cells were isolated from a confluent flask, and about 10,000 cells were placed in each well of a 96 well plate and incubated in a CO2 incubator for 24 hours. The next day, media was removed, and cells were incubated in serum-free media containing varying concentrations of papaya leaf, skin, pulp, or seed extract for 24 hours. After treatment with papaya extract, 10 μl of WST-1 was added in each well, and the plate was read at 420 nm in a 96 well plate reader for the background reading. The plate was then incubated for 3 hours at 37 ℃ in a CO2 incubator, and the reduction of WST-1 dye due to mitochondrial oxidation was recorded at 420 nm. The change in absorbance was calculated by subtracting the initial reading from the final reading. The results are expressed as % change from control (untreated cells).

Data analysis

The data are expressed as mean ± SD for at least three replicates. All comparisons were made by one-way ANOVA with Tukey’s -HSD-post-hoc test using SPSS Statistics 20 software (IBM, Armonk, NY). All significant differences are reported as P < 0.05 and indicated by “*” whereas non-significant differences are not marked.

Results

Characterization of papaya extract for anti-oxidation activity

The anti-oxidation potentials of papaya extracts were determined by assessing their total polyphenol content, total flavonoid content, and by assaying their anti-oxidation capacity. The data showing the total phenolic contents are presented in Table 1 and reported previously [28]. The highest amounts of polyphenols were found in the seed extracts that ranged 14 -16 mg/g dry weight. There was no significant difference in total phenolic contents between water and methanol extracts from papaya seeds. The leaves were second highest in total phenolic content but had a significantly lower amount of total phenolic content than that of seeds (P < 0.05). The leaves contained 1- 4 mg/g dry weight total phenolic content. Water extracts of leaves contained less total phenolic content (~ 1 mg/g dry weight) compared to that of methanol extracts. The skin extracts contained total phenolic content ~ 0.5 - 1 mg/g dry weight, whereas the pulp extracts have very small amounts of total phenolic content (0.05 - 0.5 mg/g dry weight).

The data for the total flavonoid contents in various papaya fractions are presented in (Table 2) and reported previously [28]. The water extract of seeds contained the highest amounts of total flavonoid content (5 mg/g dry weight), whereas the methanol extracts contained lower amounts (2-2.5 mg/g dry weight, P < 0.05). In leaves, the methanol extract contained more total flavonoid content (~ 5mg/g dry weight) than that of water (~2 mg/g dry weight). The total flavonoid contents in pulp and skin were less than those of seeds and leaves. In the skin, higher total flavonoid contents were present in the methanol extracts (~ 3.2 - 3.5 mg/g dry weight) than in water extracts (1 mg/g dry weight). The pulp contained the lowest total flavonoid contents compared to other fractions. The total flavonoid content in pulp ranged from 1 - 1.5 mg/g dry weight.

The anti-oxidation capacities of papaya fractions were measured by assaying the inhibition of DPPH oxidation and are shown in (Table 3) and reported previously [28]. The seeds and leaves contained significantly more (P < 0.05) anti-oxidation capacity than that of the skin and pulp. The methanol fractions of seeds and leaves contained more anti-oxidation activity than water extracts. The methanol fractions of seeds and leaves inhibited DPPH oxidation by 75 - 85%, whereas the water extracts of these fractions inhibited DPPH oxidation by 50 - 70%. The skin and pulp inhibited DPPH oxidation from 25 - 35%. There were no significant differences between water or methanol extracts of skin and pulp.

Effect of papaya water extracts on T- cell leukemia

The effects of papaya water extracts from different fractions are presented in Figure 1. The treatment with leaf extract caused a dose-dependent decrease in cell viability. A concentration of the extract as low as 50 μg/ml caused significant cell death by 30% (P < 0.05). Upon increasing the extract concentration more cells died, reaching a plateau of almost 70% cell death (P < 0.05) at 150 μg/ml. Additional increases to 250 μg/ml concentration resulted in a very small change in cell viability (Figure 1).

The treatment with water extract from papaya seeds caused a dose-dependent decrease in cell viability. Extract concentrations as low as 150 μg/ml caused a significant 20% increase in cell death (P < 0.05). On further increasing the extract concentration, no further decrease in cell viability occurred, which reached a plateau at 250 μg/ml with 25% cell death (P < 0.05) (Figure 1)

The water extract of papaya skin started to significantly (P < 0.05) inhibit leukemic cell proliferation at 25 μg/ml, causing about 30% cell death. However, the leukemic cells progressively died in a dose-dependent manner reaching to about 80% cell death at 250 μg/ml of the dried papaya skin extract.

The water extract from papaya pulp was unable to cause significant cell death of Jurkat leukemic T-cells.

Effect of papaya methanol extracts on T- cell leukemia

The effects of papaya methanol extracts from different fractions are presented in Figure 2. The methanolic extract of papaya leaves appeared to be less effective than water extract. At 25 μg/ml a significant (P < 0.05) 30% decrease in cell viability resulted; however, the cell viability was decreased by only 60% (P < 0.05) on further increasing the methanolic extract concentration to 250 μg/ml. Similarly, the methanolic extract of papaya seeds appeared to be less effective than water extract. At 200 μg/ml, a significant P < 0.05) decrease in cell viability resulted (10%); however, the further decrease in cell viability was not significant at 250 μg/ml. The methanolic extract of skin also caused significant cell death by 25% at 25 μg/ml (P < 0.05). Further increase of the extract concentration resulted in a dose-dependent response reaching 80% cell death at 250 μg/ml .

The methanol extract from papaya pulp caused a modest significant effect by decreasing cell viability by 20% at 50 μg/ml ; however, on increasing the concentration of pulp extract to 250 μg/ml , there was no further increase in cell death.

Effect of papaya water extracts on B- cell leukemia

The effects of water extract from different papaya fractions on Daudi leukemia B-cells are presented in Figure 3. Treatment with leaf extract caused a dose-dependent decrease in cell viability. Concentrations as low as 25 μg/ml caused a significant 20% cell death (P < 0.05). On further increasing the extract concentration, significantly more cells (P < 0.05) died in a dosedependent manner, with approximately 50% cells dead at the highest concentration of 250 μg/ml. The water extracts from seeds and pulp have no significant effect on cell viability at any concentration. The extract of papaya skin started to significantly (P < 0.05) inhibit leukemic cell proliferation at 25 μg/ml causing about 25% cell death. However, on further increasing the extract concentration, no change in cell death was observed

Effect of papaya methanol extracts on B- cell leukemia

The effects of methanol extracts from different papaya fractions on Daudi leukemia B-cells are presented in Figure 4. The methanolic extract of papaya leaves appeared to affect Daudi B-cells, similar to water extracts. At 50 μg/ml, a significant 30% (P < 0.05) of cells died and the cell death was further increased in a dose-dependent manner to 80% (P < 0.05) at 250 μg/ml. Consistent with the water extract, the methanol extract of papaya pulp has no effect on Daudi B-cells. The methanolic extract of skin had a similar effect on Daudi B-cells as the water extract. It caused significant cell death by 25% at 25 μg/ml (P < 0.05). Increasing the concentration of extract resulted in a dose-dependent effect, reaching 50% cell death at 250 μg/ml.

Discussion

The present study was carried out to investigate the effect of water and methanol extracts of papaya leaves, skin, pulp, and seeds on Jurkat leukemia T- cells and Daudi leukemia B-cells. Water and methanol were used because phenolic compounds have different chemical characteristics and polarities, and because of these properties, compounds in different fractions of papaya may or may not be soluble [30]. We initially tested these fractions for their phenolic contents and their anti-oxidation activity. Most of the anti-oxidation activity in fruits and vegetables is due to their total polyphenolic contents [31]. Our data indicate that papaya seeds have higher amounts of polyphenols than that of other fractions (Table 1). Papaya leaves also contained substantial amounts of total phenolic contents but were 1/3 that of seeds. Other fractions have very little total phenolic content. In seeds, the amount of total phenolic content was similar in both extracts, but the leaf water extract has less total phenolic content than that of methanol. However, the water extract of skin contained almost twice the polyphenols than that of the methanol extract. Organic solvents are generally used to extract bioactive agents from fruits and vegetables. The most suitable solvents for the extraction of polyphenols are aqueous mixtures containing ethanol, methanol, acetone, and ethyl acetate. Ethanol has been known as a good solvent for polyphenol extraction and is safe for human consumption. Methanol has been generally found to be more efficient in the extraction of lower molecular weight polyphenols, whereas aqueous acetone is good for the extraction of higher molecular weight flavonoids [32]. Currently, over 8000 phenolic structures have been identified in fruits and vegetables [33], and flavonoids are one of the major phenolic classes comprising almost 4000 compounds present in different edible plants [33]. We also determined the total flavonoids in the papaya extracts. Our data show that water extracts of seeds and methanol extracts of leaves contained the highest amount of total flavonoid content, which represented about 30- 40% of total phenolic compounds in seeds and leaves (Table 2). The data suggest that most of the polyphenols in seeds are water-soluble flavonoids, whereas a higher proportion of polyphenols in leaves are less water-soluble flavonoids.

Next, the anti-oxidation activities were determined in these fractions. The leaves and seeds possess a higher anti-oxidation activity compared to that of other fractions (Table 3). Although leaves and seeds have different phenolic and flavonoid contents, they have similar profiles for their anti-oxidation activity. It was interesting to note that methanol extracts exhibited higher antioxidation activity than the water extracts. This difference could be due to the different natures of polyphenols.

Next, we analyzed the anticancer properties of papaya fractions on Jurkat cells and Daudi cells. The Jurkat cells are an immortalized line of human T lymphocyte cells that are often used to study acute T cell leukemia. The Jurkat cell line was established in the late 1970s from the peripheral blood of a 14-year-old boy with T cell leukemia [34] whereas the Daudi cell line is a wellcharacterized B lymphoblast cell line which was derived from a 16-year-old black male with Burkitt’s lymphoma [35].

A large number of phytochemicals from vegetables, fruits, and grains have been reported to possess anticancer properties and are promoted for cancer prevention and treatment [36-40]. Recently, multiple scientific reports have emerged about the medicinal benefits of papaya [16,41-43].

Our data indicated that none of the extracts from seeds or pulp possess significant inhibitory activity for cell proliferation in Jurkat leukemic T-cells or Daudi leukemic B-cells. The extracts from leaves and skin, however, showed significant inhibition of both Jurkat leukemic T-cells and Daudi B-cell growth. This effect was stronger on Jurkat T-cells and modest on Daudi B-cells. During the present study, we found that papaya seeds contained the highest amounts of phenolic compounds; however, none of the extracts from papaya seeds have any inhibitory activity for Jurkat leukemic cells. Our data clearly indicated that the inhibitory activity of these extracts was neither dependent on their phenolic contents, nor was it dependent on their anti-oxidation activity. It appears from this observation that the inhibitory compounds in papaya leaves and skin extracts acted on cellular mechanisms linked to cell growth. For example, phytochemicals have been shown to interfere with the stabilization of the microtubule structure, thereby inhibiting mitosis and cancer cell propagation [44]. Vincristine and vinblastine, isolated from the leaves of Madagascar periwinkle, were the first phytochemicals to be used clinically in combination with other anticancer agents in lymphomas, leukemias, and breast, lung, and ovarian cancers [45,46].

Epigallocatechin-3-gallate (EGCG), a polyphenol from the leaves of Camellia sinensis (processed to green tea), possesses anti-oxidation activity but it limited cancer cell proliferation by reducing DNA methylation through the inhibition of DNA methyltransferase together with reactivation of the silenced tumor suppressor genes [47]. Curcumin (diferuloylmethane), a polyphenol isolated from the rhizome of the turmeric plant, has also shown therapeutic efficacy on numerous disorders, including cancer [48]. Curcumin is reported to inhibit NF-κB signaling that triggers the intracellular inflammatory response as well as cellcycle- associated genes. By arresting the cell cycle and inducing apoptosis through the relaying pathways, curcumin interferes with angiogenesis and reduces tumor invasion.

An additional group of anticancer phytochemicals functions as inhibitors of topoisomerase I or II, which are the nuclear enzymes that control DNA supercoiling, eliminate tangles in the chromatin structure, and allow DNA to be replicated and transcribed. Thus, topoisomerase inhibitors can act as anticancer agents by inducing a delay of the cell cycle, followed by cell death [36]. β-Lapachone from the bark of the Lapacho (Handroanthus impetiginosus) plant, camptothecin from the bark/stem of Camptotheca acuminata (the Chinese happy tree), and podophyllotoxin from the root of the Mayapple (Podophyllum peltatum) plant are examples of phytochemicals inhibiting topoisomerases in cancer cells [49- 51]. We have not yet characterized the chemical composition of aqueous and methanolic extracts of leaves and skin or explored the molecular mechanisms that may be involved in inhibition of Jurkat leukemic cell growth. Clearly, additional experiments are required for isolation and identification of active compounds in papaya leaves and skin to determine the cellular mechanisms of their anticancer activity.

Our data suggest that consumption of papaya leaves or skin may be beneficial for preventing and/or treating leukemia, particularly T-cell leukemia. Historically, papaya leaves have been used in different cultures around the world, which suggests that the consumption of leaves extract is not toxic [52]. It is possible that anticancer compounds from leaves can be extracted by boiling them in water. However, the skin is not typically consumed because of its bitter taste. The skin can be dried and made into a powder that can be consumed in the form of pills. Alternatively, the active compounds from leaves and skin can be extracted and isolated in pure form, which can be the basis for new therapeutic leukemia drugs. In conclusion, this study suggests that leaves and skin of papaya contained anticancer activity for leukemic cells.

To Know More About Nutrition and Food Science International Journal 

Please click on: https://juniperpublishers.com/nfsij/index.php

For more Open Access Journals in Juniper Publishers

please click on: https://juniperpublishers.com/index.php

[juniperpublishers-nutrition]

Non-Centrifugal Cane Sugar is a Potential Functional Food?

Abstract

Non-centrifugal sugar (NCS) is a traditional sweetener consumed worldwide. Previous investigations have reported that NCS is an important source of nutritional and bioactive compounds. The results show that NCS is of great scientific and nutritional and technological interest due to its potential beneficial effects on health. However, better characterization is required to recognize NCS as a functional food.

Keywords:Sugar cane; Antioxidants compounds; Functional food; Amino acids; Complex sugars

Introduction

Nutraceuticals and functional foods have broad potential for preventing the mechanisms of viral infection and modulating immune responses [1], for this reason, in the last decade this topic has been widely studied. Non-centrifugal sugar (NCS) is a traditional sweetener consumed worldwide Flórez-Martínez et al. [2] that contains abundant amounts of sucrose and potentially relevant components like phenolic compounds, amino acids, complex sugars and other compounds that make it different from refined sugar [3]. Interest in the constituents of sugarcane and its products has been rekindled by the recognition that sugarcane juice and some of its products, particularly un-refined sugars, less-refined sugars, and molasses, have antioxidant capacities. Previous authors have reported that NCS is an important source of nutritional and bioactive components [4-8]. The aim of this review to provide a comprehensive overview of beneficial reports of NCS properties from antioxidants compounds and other potentially relevant components.

Methodology

Relevant studies published in scientific journals were analyzed. The search was done in the Scopus database using a structural equation with keywords. Keywords related to minerals, vitamins, antioxidants, and other potentially relevant components and their effect on health were used in this search.

Health Effects of NCS

NCS can be considered as a potential bioactive product. The cane plant itself supplies primarily low molecular weight plant pigments (flavonoids, chlorophylls, carotenes, xanthophylls and phenolic compounds [5]. Previous research [8-11] have demonstrated the antioxidant activity of NCS. Furthermore, Asikin et al. [9] reported policosanol content in NCS, which may have beneficial effects on human health. Different in vitro studies have reported the effect of the antioxidant activity of NCS. Harish Nayaka et al. [7] showed that NCS has a 97% protection against the oxidation of NIH 373 cells. Salazar et al. [12], demonstrated the neuroprotective and antioxidant effects of NCS. Cuellar et al. [13] studied the potential regenerative effects of NCS in a 2D Skin wound Model. In addition, the effect on diseases such as the decrease in the proliferation of tumor cells in leukemia, stomach, lung, colon, and bladder cancer has been demonstrated [14]. An antitoxic and cytoprotective effect has also been demonstrated. Of the studies reviewed, only two articles report the beneficial effects of NCS in human trials [14]. Jaffe [14] showcased the state-of-the-art research reporting the health benefits associated with NCS consumption. The reported benefits include immunological effects, as well as cytoprotective, antitoxic and anticariogenic effects. Also, he found that NCS has the ability to scavenge free radicals, reduce iron complex, and inhibit lipid peroxidation.

Conclusion and Future Prospect

NCS is of great scientific, nutritional and technological interest due to its potential beneficial effects on health, but a better characterization is required. In addition, this antioxidant and healthy product could have a more relevant position as a key nutritional component in a wide variety of foods. In this way, the recognition of NCS as a promising functional food would be promoted, and it would be hoped that research efforts would be increased to extend its use.

To Know More About Nutrition and Food Science International Journal 

Please click on: https://juniperpublishers.com/nfsij/index.php

For more Open Access Journals in Juniper Publishers

please click on: https://juniperpublishers.com/index.php

[juniperpublishers-nutrition]

Physicochemical and Sensory Characterization of Pitaya (Stenocereus thurberi) Jelly

Abstract

The pitayo (Stenocereus thurberi) is an indigenous cactus from northern Mexico and the southwest region of United States which produces a small, sweet fruit known as pitaya, which is closely related to pitahaya (Hylocereus genus) or dragon fruit. In this study, pitaya fruit were processed to obtain a jelly. The fruit was harvested from wild plants of the Sonora desert to formulate four different jellies using sugar (33 % or 50 %) and pectin (0.8 % or 1.2 %), which were then sensory evaluated. The total soluble solids concentration of jellies varied from 65 % -67.5 %; the pH from 3.6 - 4.2; the water activity (aw) was measured at 0.69 - 0.77; and the reducing sugars fluctuated between 23 % - 33 %. The product composed of 49.2 % fruit, 50 % sugar and 0.8 % pectin had the lowest spreadability score, as well as the lowest viscosity value of 2.64. This food product could be profitable for local communities due to the high perishability of the pitaya fruit, which also has a very short harvest period.

Keywords: Pitaya; Jelly; Viscosity

Introduction

There is a great variety of fruit that are in high demand locally, and worldwide. These include vine, mango, tomatoes, citrus, strawberries and others, which are generally high-water demanding crops, and frequently attacked by diseases; thus, affecting their production yield or/and increasing their retail price [1-3].

Mexico within its territorial surface, has 80,000,000 ha of arid and semi-arid of regions mostly distributed in the northern, center and southwest regions of the country [4]. The main limitation for these regions to be used as farmlands is the lack of irrigation water [5]. Due to the low availability of water on the surface of the land, both annual crops and perennials are irrigated during their cultivation with water from underground sources [6,7]. Of these rains, surface runoff is mostly stored in reservoirs within the Yaqui and Sonora rivers pluvial system. For instance, Sonora, a semi-desert region of northwestern Mexico, receives approximately 80 % of its rainwater during July, August, and September, through a phenomenon known as the Mexican monsoon characterized by a dramatic increase in rainfall [8]. The pecan walnut and the vine are the main perennial crops in the region representing around 30 % of the total cultivated area, and they consume more than 50 % of the aquifers annual recharge [9].

In contrast, there are other non-conventional fruit species marginally exploited including some species that are not very demanding in terms of water requirements. Thus, being able to develop in arid and semi-arid conditions due to physiological and morphological adaptations allowing them to grow in these environments [10]. These modifications includes: stems capable of storing water; absence of leaves or modified leaves; waxy cuticles; ribs and tubers that allow the stem to expand and contract in response to changes in water availability; and roots that are generally shallow and non-succulent. These characteristics allows these plants to be very efficient in the use of water, typically, 5 to 10 times more than conventional crops [11]. Typical examples of these plant species are cacti which have had great importance in subsistence agriculture for the inhabitants of these regions. Of note, those known as garambullo from Myrtillocatus geometrizans (Martius), console, tuna or “cactus pear” (Opuntia spp.), and pitaya (Stenocereus spp.) [12]. The commercial exploitation of these fruit species in arid and semi-arid is limited. However, some cactus species such as pitaya-producing plants stand out, with potential for regional, national and international markets [13]. The fruit is usually obtained from wild plants, sold in local markets and transported to nearby cities [12]. Due to its organoleptic properties (color, flavor, and aroma), pitaya fruit is in great demand for consumption during the season as fresh fruit, frozen products, and jams. However, processing is challenging due to its low acidity and high pH [14]. These characteristics have posed problems related with the stability of pitaya pigments in the elaboration of juices and confectionery [15-8].

The current use of processed pitaya fruit in Sonora is the preparation of a homemade sweet. More recently it has been marketed as frozen products such as popsicles and ice-cream. In this region, pitaya-producing plants have not been systematically cultivated, and are only found in the wild, from which the fruits are collected to be consumed and marketed as fresh. The lack of information regarding the behavior of this fruit, as well as the lack of knowledge concerning its transformation are the main reasons why its commercialization has not been achieved. Therefore, in this work, the feasibility of making a jelly-like product based on pitaya fruit is proposed, portraying an industrialized process.

Materials and Methods

Plant Material

Pitaya fruit (Stenocereus thurberi) was harvested near Carbó Municipality (29°34’29.79”N 111°0’51.02”W), Sonora, Mexico during June, and July. Ripe and over-ripe red fruits (closed and open) were used to produce the jelly. The seeds were eliminated by porous sieves until obtaining the fruit juice.

Jelly formulation

The total soluble solids of the extracted juice were determined using a refractometer Abbe (model 10450) to calculate the weight of the final product and pectin by equation (1) and (2):

where:

F: Weight of the final product (g)

A: Weight of the fruit per load (g)

Xa: % fraction of the °Brix of the fruit.

Az: Weight of sugar per load (g)

Xf: % fraction of the desired ° Brix.

P = F ×WP (2)

where:

P: Weight of pectin (g)

F: Weight of the final product (g)

Wp: % of pectin required

The proportion of commercial sugar, pectin (150 grade, USASAG, IFT 1959) and commercial citric acid were determined according to (Table 1).

Jelly making process

Pitaya juice, to which pH and total soluble solids content (°Brix) were initially determined, was placed in a 2 L stainless steel pot. Heating, using a commercial stove (VWR, 1324, Cornelius, OR, USA) was started with continuous stirring until the product was brought to a boil (90-95 °C). From this moment, the monitoring of the concentration of total soluble solids began, sampling at intervals of 3-5 min. Once 20-24 °Brix were reached, a homogeneous hot sugar syrup was added with 50 % of the total citric acid obtaining the inversion of sucrose to prevent its crystallization during storage [19]. After the syrup was added, the boiling continued as well as controlling the total soluble solids content. The process was maintained until reaching 62 °Brix, at that time, the product was removed from the heat source. When the product cooled, total soluble solids content, and pH were determined, and the jam was packed in plastic containers with hermetic lids.

Physicochemical determinations

Direct Reducing Sugars, ° Brix and pH

Water activity

The water activity (Aw) of jellies was determined at a constant temperature using a thermo-hygrometer (Higroline HTC-2, Beckman Industrial) provided with a relative humidity sensor. The instrument was previously calibrated using the standard salts provided by the manufacturer, corresponding to three relative humidity points: 11.3 %, 52.9 %, and 90.2 %. The Aw determination was assayed by placing 3 g of each sample in the appropriate containers to reach its relative equilibrium humidity (approximately after 5 h) and then, Aw was calculated using the equation 3:

where:

Aw: Water activity

% RH: equilibrium relative humidity between food and environment

Viscosity

The viscosity of the jellies (pour in a 100 mL beaker), was determined by means of a rotational viscometer (Brookfield, LVTD). The 4 LV needle (radius 0.1588 cm; effective length 3.4 cm) was selected, based on preliminary tests, allowing the generation of viscosity readings within the range between 10 and 100 Brookfield units (BU). According to Canovas, et al. [21], the jellies of some fruits follow a non-Newtonian type flow behavior independent of time. The previous behavior was taken as a basis for the pitaya jelly. The working formula used for the development of the power law model for the rotational viscometer was the following:

where:

Ω : Rotor angular speed (Rad s-1)

M: Torque (N m)

h: Effective length of cylinder (m)

Rb = Radius of the container (m)

Rc = Radius of cylinder (m)

η : consistency coefficient (Pa s)

n: Flow behavior index

This formula corresponds to the equation of a line. Thus, to obtain each parameter of this equation, the values of Brookfield Units, as well as the speed of the rotor, underwent transformations and were adjusted by means of least squares. The flow behavior index (n) was obtained as the inverse of the slop (m) value. The ordinate to the origin was used to calculate the consistency coefficient according to the following equation:

where:

K: Consistency coefficient (Pa sn)

n: Flow behavior index

b: Intercept

h: Effective length of cylinder (m)

Rb = Radius of the container (m)

Rc = Radius of cylinder (m)

To calculate the flow behavior index (n) and the consistency coefficient (K), readings were obtained at different rotor speeds (12, 30 and 60 rpm), obtaining values of 10-100 BU, with all samples previously equilibrated at 24 °C.

Sensory evaluation

Judges

A semi-trained sensory panel of 24 judges of both sexes was gathered. The panelists ages varied from 22 to 31 years old. Before the session, an explanation regarding the mechanism for completing the questionnaire was provided.

Sensory methods

Four pitaya jellies were selected for sensory evaluation. They contained the same acid concentration (0.3 %), two different proportions of sugar (33 % and 50 %), as well as two different proportions of pectin (0.8 % and 1.2 %). Acceptability tests included attributes of color, flavor, texture (consistency) and general acceptability. A hedonic or acceptability questionnaire (very good, good, slightly good, neither good nor bad, slightly bad, bad, very bad) was developed to score samples.

Statistical analysis

Data from the sensory evaluation was examined by two-way analysis of variance for each one of the sensory attributes studied, using the information provided by the judges during the evaluation session. The two factors were, on the one hand, the experimental treatments (samples of jellies) and on the other hand, the judges. Mathematical transformations of hedonic responses to numerical scales was perform. A value of 7 was be given to the highest evaluation point up to a value of 1 to the lowest rating. The data was analyzed using the STATPACK statistical package.

Results and Discussion

Physicochemical parameters

The initial plan of the experiment was to determine the most acceptable jelly by altering the amount of fruit, sugar, pectin, and ascorbic acid. However, it was evident that the maximum acid content that the jelly could present was at 0.3 %. Higher levels of acidity in the jelly derived on lower acceptability scores. Therefore, four jellies were chosen as the most acceptable according to the previous consideration. The formulation of the selected jellies is presented in Table 2.

Quality parameters

The total soluble solid values obtained for each jelly were maintained in a range of 65 to 67.8 ° Brix, which are adequate for the gel formation (Table 2). To be optimal as a gelling agent, pectin should be in a matrix with at least 65 °Brix [22]. The pH value for each of the jellies is also presented in Table 2. It can be noted that similar to the total soluble solid content, the pH of the jellies allowed the jellification. In addition, it is important to note that a grade 150 + 5 pectin was used in this study. This is a high-grade rapid gelling citrus pectin capable to gel up to 150 parts of sugar under specific conditions. This type of pectin can perform effectively in a pH range from 3.4 to 4.2 [22]. Therefore, the prepared jellies also met this condition, since none exceeded this range (Table 3).

The nutritional composition of the pitaya fruit jellies (Table 2) was comparable to the values found in dragon fruit (Hylocereus undatus) reported by [23]. Where the content of pectin and sugar for at least one pair of jellies, was 33 % of sugar. Likewise, the direct reducing sugars values (32.9 % and 23.6 %) were related to those described for strawberry jam by Cano [24], and for dragon fruit (Hylocereus undatus), registered by [23]. The Aw values included in Table 2 place the pitaya jelly as an intermediate moisture food, since it presented an Aw value in the range of 0.6 to 0.92 [25]. These foods must not allow microbial growth, nor the development of deteriorating reactions, and must also have adequate sensory characteristics. A comparative study carried out by Cano [24] reported values in the range of 0.9 to 0.93 for Mexican candies including jams, viznagas and jamoncillo; the jellies on the other hand had a lower Aw at 0.69 to 0.77. All bacterial growth is drastically reduced at Aw values less than 0.85, yeast growth is reduced at Aw values less than 0.78, and fungal growth is reduced in environments with less than 0.62 Aw values [26]. Thus, fungal growth can be expected if the jellies are stored at high temperatures. Therefore, a food preservative could be considered to prevent the growth of fungi. Sodium benzoate could be incorporated in the jelly at a concentration of 0.1 % and to obtain a more stable product.

Viscosity

The rotational viscometer allowed the generation of data applicable to the proposed model to establish the rheological characterization of the pitaya jellies. The values of consistency coefficients (K) and flow index behavior (n) for the jellies are shown in Table 3. The jelly I exhibited a lower consistency value compared to the other formulations, which were kept in a narrow range of 8.50-9.86 Pa s (Table 3). The decrease in the consistency coefficient was associated with a poor gelling effect of pectin in the medium. Additionally, this jelly was also classified as “very soft” by the panelists (Table 4). In the case of vegetable-origin products, such as the case of the jelly, the consistency coefficient of a suspension mainly depend on the solids content, as well as the viscosity of the suspending medium [27]. In the formulation I, the solids content was similar to other jellies, confirming that jelly consistency is related to the gelling activity of pectin. On the other hand, the lowest pH value of all formulations was observed on jelly I (3.60). Thus, it would have been expected to this formulation formed the best gel, yet it was the least firmness the gel of all. This might have been related with a deficient pectin activity in that formulation.

Formulations II, III and IV were very similar in terms of their consistency values. Even though jelly III was slightly higher at 9.87 Pa.s (Table 3), this jelly was also the one with the highest solids content. The flow behavior index values obtained (<1.0) ensured that the pitaya jelly behaves like a non-Newtonian pseudoplastic fluid [28]. This is in agreement with other studies, including concentrated apple juice (65 °Brix, n=0.65) [21]; tomato puree (n=0.44) [29], as well as that of mustard with (n=0.33) [30]. Rao [27], have described that in suspensions of vegetable-origin, such as concentrated juices, the content of pulp is very important on flow parameters. In concentrated orange juice (65 °Brix), this author has reported consistency coefficient values of 13.92 Pa s. Also, in similar matrices, there is an important effect of the serum, or the medium in which the solids are suspended, and its consistency is determined by the sugar and the pectin content. Furthermore, these two factors have a high correlation, and even the pectin content alone is a good parameter to estimate the serum viscosity [31]. Once this value has been obtained, along with the pulp content, it is possible to predict the consistency coefficient of the complete system. The relevance of the prior is that they demonstrate that pectin plays an important role on the product viscosity. It should be highlighted that when examining non- Newtonian type fluids, the viscosity should not be evaluated with a single point, since there is no linear function between the shear rate (γ) and the consistency coefficient (η) [32]. Thus, different rotor speeds were selected, to obtain various readings and more reliable results. The obtained parameters are of practical relevance since friction factors and the Reynolds number, necessary for the design of industrial processes, can be directly estimated [33].

Sensory evaluation

The global results of the sensory analysis of the four jellies are tabulated in Table 4. The 5 attributes studied, and the means of the 24 replicates are included. Of all attributes, significant differences (p < 0.05) were only observed on spreadability from the formulation I (50 % sugar 0.8 % pectin, and 66.2 °Brix). The rest of the jellies had similar spreadability values and corresponded to a texture that was neither soft nor hard. In jellies I and II, which contained the highest proportion of sugar but different pectin content, the firmness improved when the pectin content increased, similar to that reported for dragon fruit [23]. This was reflected in the sensory evaluation of the panelists to jelly I, giving it the lowest rating for the spreadability attribute, being significantly different from jelly II which contained 1.2% pectin in its formulation. The samples were also evaluated for the attributes of aroma, flavor, color and general acceptability. The scores are shown in Table 4, where no significant differences were found among the evaluated attributes in the four samples. Nevertheless, it was observed that the formulations with the highest percentage of pectin achieved the best scores. A similar trend was observed for Dragon fruit jelly, although in his case, statistically significant differences were found in color and general acceptability [23]. On the other hand, it has been reported, that the low pectin content is insufficient to achieve a good quality prickly pear jellies, due to the use of ripe and overripe fruits [14]. This might have been the case in this study where the pectin content in pitaya fruit decreases considerably when is overripe.

Conclusion

The information provided by this study sets the tone for future research for the use of this fruit on unutilized land on arid regions. As well as the feasibility to establish micro-industries in rural areas capable to transform the pitaya fruit in food products which could increase the development of those regions.

To Know More About Nutrition and Food Science International Journal 

Please click on: https://juniperpublishers.com/nfsij/index.php

For more Open Access Journals in Juniper Publishers

please click on: https://juniperpublishers.com/index.php

[juniperpublishers-nutrition]

The Needs and Applications of Delivery Systems to Fortify Food with Active Ingredients

Abstract

Fortifying food products with bioactive agents is a major initiative within the food industry for human health. However, many agents are water insoluble with low bioavailability; some are unstable and easily degrade during storage. Thus, it is necessary to overcome these obstacles before adding them to the final food products. Entrapping bioactive agents into suitable delivery systems such as liposomes, emulsions, etc., has been proven to be a useful method. This review simply describes the reasons for bioactive agents needed to be entrapped in delivery systems, the common formulations used, and their applications. This would provide a general understanding of how active ingredients generally enrich food.

Keywords: Active ingredients; Delivery systems; Emulsion; Liposome

Introduction

Consumers are increasingly demanding a healthy diet rich in active ingredients such as flavors, vitamins, minerals, antioxidants, lipids and so on [1-3]. However, on the one hand, the compositions of active ingredients in natural food are usually limited; on the other hand, some agents may be high in raw food, but their bioavailability is very low [4-6]. For example, β-carotene has received increasing attention during the past 30 years due to its beneficial health effects such as antioxidant and anticancer activities as well as its ability to reduce the risk of heart disease and certain chronic disease [7]. However, humans cannot synthesize β-carotene in their bodies, and they must obtain it from the foods they consume. Many vegetables and fruits (peppers, tomatoes, carrots, mangoes, and kale) are rich in β-carotene, but literatures show that only a minor part (<10%) of the carotenoids in these raw foods is absorbed [8,9]. In addition, many active ingredients including β-carotene also have many other disadvantages such as low water-solubility, physical or chemical instability, undesirable flavor, and so on [10-12]. All of them make active ingredients difficult to directly incorporate into final food products. Therefore, development of strategies to incorporate active ingredients is necessary if such foods are to keep successful and initiative in the marketplace.

Luckily, these challenges can be overcome by entrapping active ingredients into suitable delivery systems. During the past decades, delivery systems (such as liposomes, emulsions, lipid particles, microcapsules, beads, etc.) have been effectively designed and utilized in food industry to encapsulate, protect, and deliver functional components before introduced into final food products [13-16].

Among of them, emulsions especially for oil-in-water emulsion have attracted the interest of many research groups in food and pharmaceutical fields due to their favorable properties such as good biocompatibility, easy design and preparation [3,17]. To obtain uniform emulsion, the oil phase dissolved with bioactive agents is mixed with emulsifier water solution, blended and then passed through a homogenizer. In this system, emulsifiers play an important role in the formation of emulsion and its stability thereafter. To be an effective emulsifier, ingredients should exhibit perfect emulsifying activity [18]. That means it should quickly adsorb to the surfaces of small oil droplet form an interfacial coating and appreciably decrease the interfacial tension during homogenization [3]. Synthetic emulsifiers such as Tween 20, tween 80 are the traditional emulsifiers for many products. With the increasing demand for food and beverage with natural ingredients in recent years, many food manufacturers are trying to replace synthetic emulsifiers with natural and sustainable alternatives. To date, researchers have found a lot of natural emulsifiers (such as protein, polysaccharides, phospholipids, and bio surfactants), which are able to form and stabilize oil droplets [18-21]. Chung et al., [18] found that emulsion prepared by using quillaja saponin as a natural emulsifier could produce whitish milk similar to a commercial liquid creamer. Lin et al., [22] have prepared β-carotene loaded emulsion by using modified starch. He et al., [4] have fabricated curcumin emulsions containing Konjac glucomannan stabilized with whey protein isolate and achieved a controlled and sustainable release of bioactive compounds from emulsions. Lv et al., [20] have compared the effectiveness of a number of natural emulsifiers (whey protein, gum arabic and quillaja saponin) on the production and stability of vitamin E fortified emulsions and found that whey protein isolate and quillaja saponin were more effective at forming emulsions containing fine droplets than gum arabic, while quillaja saponin based and gum arabic based emulsions exhibited better resistance to pH change. Due to the above-mentioned advantages, emulsions are already widely utilized in the food industry, e.g., in dressings, sauces, soups, beverages, dips, creams, and desserts [6,19,22].

Liposome, as one of the most common used formulations, also has great potential to embed bioactive agents. A liposome is a self-assembling and cell-resembling delivery system with concentric bilayer structure. The size of liposome is typically about 10 to 1000nm with the structure varying from a balloonlike unilamellar to an onion-like multiple structures [3,12]. There are different hydrophilic and hydrophobic regions in liposomes separated by surfactant substances (such as phospholipids) [3]. Therefore, both hydrophilic and lipophilic molecules and even amphiphilic molecules can all be entrapped in the special bilayer. Since liposomes were first described in the 1960s by Alec Bangham, they have been beneficial in medical, cosmetic, and agricultural fields, and have become integral to food research. More recently, liposomes have been widely used to encapsulate proteins/peptides/enzymes, polyphenols/flavones, essential oils/fatty acids, vitamins, energetic substrates, and minerals [3,23-25]. Active agents in the form of liposomes could then be effectively added into different food products: dairy products (milk, cheese, and yogurt), drinks (juices and milk drinks), meat (pork, beef, and rabbit), and other products (chocolate, tofu, etc.) [12,27-32].

Delivery systems containing bioactive agents could be directly added into food material with simple blending or homogenization and bring a number of benefits to food industry: supplying good protection for bioactive agents against environment stress, masking off-flavor (bitterness, astringency), improving storage and handling characteristics, extending shelf life, besides increasing bioavailability. However, the food system microenvironment (pH, intrinsic component, and ionic strength etc.) and emulsifier properties used are critical factors needed to take into account if appropriate final food is wanted [3,6]. For example, whey proteinbased emulsion could effectively inhibit oxidation of fish oil in milk, but is less stable in yoghurt and dressing [18].

Conclusion

A number of challenges associated with active ingredient need to be addressed when incorporated into food. Suitable delivery systems such as emulsions, liposomes, etc. could be designed to encapsulate active agents followed by simple blending or homogenization. However, whether appropriate final food could be obtained is dependent on food and emulsifier properties.

To Know More About Nutrition and Food Science International Journal 

Please click on: https://juniperpublishers.com/nfsij/index.php

For more Open Access Journals in Juniper Publishers

please click on: https://juniperpublishers.com/index.php

[juniperpublishers-nutrition]

Bacteriophages as Preservation Agents to Promote Minimally Processed Food Safety

Abstract

Foodborne disease related to ready to eat products contaminated by foodborne pathogens is a global concern due to its impact on human health and economy worldwide. Minimally processed food like ready to eat fruits and vegetables are not subjected to common preservation processes, additionally, the use of antibiotics and chemicals for pathogens eradication may affect consumers health. Baceriophages or viruses that infect bacteria have been suggested as bio-control tools and advantageous bio-preservation agents to promote minimally processed food safety. Recent studies show a reduction of pathogens after application of phages cocktails on fresh produce. Usefulness of broad-host range bacteriophages as bio-preservation agents needs more investigation.

Keywords: Ready to eat products; Bacteriophages; Bio-preservation; Broad-host range; Food process

Introduction

Bacteriophages or viruses that infect bacteria are extremely abundant in nature with a high diversity. There are more than 1031 phage particles in the biosphere. They outnumber bacteria in most studied habitats including human and animal associated microbial communities. Phages are considered non-pathogenic to humans and obligate intracellular parasites without intrinsic metabolism, they replicate in metabolizing host bacteria. After adsorption, phages inject their genomes into the bacterial cytoplasm and replicate by means of one or two main life cycles: the lytic cycle or the lysogenic (or temperate) cycle. During the lytic cycle they induce the bacterial mortality by disrupting host cell and releasing the phage progeny. Phages bind to specific targets on the cell wall, this specificity determinate its host range. Since their discovery by Frederick Twort (1915) and Felix d’Herelle (1917), bacteriophages were used for many applications in clinical and veterinary medicine (phage therapy), in microbial source tracking for water assessment (viral indicators of fecal contamination) and in agro-food industry (sanitation, biocontrol and food preservation) through food chain.

Aside their use in food safety for therapy by the reduction of pathogens in living animal during primary production and for the disinfection of surfaces and equipment in contact with processed food, bacteriophages could be used as a bio-preservation tool, as well.

Phages used for ready to eat food preservation can have a broad host range. Broad host range phages or polyvalent phages are capable of infecting many strains of the target, species or targets Bacteriophage host range is not a fixed characteristic of each species of bacteriophage as it evolves over time and can show unexpected plasticity cross species, genera, families and even classes boundaries.

In fact, fresh-cut vegetables and ready to eat products constitute a favorable medium for foodborne bacteria transmission to human causing foodborne illnesses and even death. Numerous pathogenic bacteria may contaminate ready to eat fruits and vegetables like Salmonella enteric, E. coli O157: H7, Listeria monocytogenes, Shigella…Furthermore, food industries are facing challenges related to the susceptibility of consumers to foodborne pathogens infections due to the high number of immune-compromised individuals and the special processing requirements for ready to eat food and fresh cut fruits and vegetables prior to commercialization. Moreover, ready to eat food is highly perishable and can’t be preserved with common processing methods including heat, pasteurization and dehydration…that may alter its organoleptic properties and reduce its nutritious value. Hence, bacteriophages seem to be appropriate for controlling bacterial pathogens in food processing environments especially ready to eat food industries as they can be used as natural antimicrobials without affecting food organoleptic properties or nutritious value. Only strictly lytic phages are used for food bio-preservation and must be well known and genetically mapped to avoid the risk of bacterial mutation and the emergence of new resistant phenotype. Regarding application for the preservation of minimally processed food, phages are used during minimal process (slicing, washing…), storage and marketing of the final product (packaging…). Despite the controversial efficiency of phages application for pathogens eradication on animal products using different strategies (oral delivery, injection…) [1-3], it seems that phages application on fresh produce and ready to eat food is very promising and effective regarding pathogens reduction and even pathogens total eradication. Knowing that the most used strategy in ready to eat food preservation reported in literature is spray of phage cocktail containing different phages against specific bacteria [4-6], it`s important to highlight that there is insufficient data concerning the use of broad-host phages to eradicate pathogens from ready to eat food. Hence, further studies are needed to be performed on this topic.

As an outcome of the latest studies on the usefulness of bacteriophages as agents for ready to eat food preservation prior to consumption, it may be concluded that the emergence of pathogenic bacteria resistant to phage infection and the choice of the most adequate strategy for phage delivery process are challenging issues that need further studies to set a strong scientific evidence required for regulations and standards authorities for a commercialized and a common use of phages as bio-preservation tools in agro-food industry. Meanwhile, the perception of “phage-treated food products “by the general public and consumer attitude should be addressed.

To Know More About Nutrition and Food Science International Journal 

Please click on: https://juniperpublishers.com/nfsij/index.php

For more Open Access Journals in Juniper Publishers

please click on: https://juniperpublishers.com/index.php

[juniperpublishers-nutrition]

What does the Name Change Entail? Differentiation of Strains for Bacterial Names

Abstract

The frequent change of bacterial names and the consequences have been discussed in brief, with recent examples of Bacillus spp, and Lactococcus spp.

Keywords: Bacterial classification, B. paralicheniformis, B. licheniformis, L. plantarum and L. pentosus

Opinion

The bacterial classification change of names “Bacillus licheniformis into B. paralicheniformis, Lactobacillus plantaruam, L. pentosus and L. paraplantarum” and implications. The change of a strain name creates many hurdles in representing, patenting, and in academic events. Even more important, patents filed under the previous name may disappear as the new name appears. The incorporation of a new name locally is easy, but this is a major concern globally. In 2019, we filed a patent on the Bioprocess developed for the purification of (B. licheniformis), bacteriocin as a result, the patent granted. During the submission of the whole genome sequence (WGS) in the NCBI portal, we were informed that this is B. paralicheniformis, but based on 16S rRNA sequence it was B. licheniformis. Identical incident observed involving L. plantarum, after submitting the genome sequence, it was informed as L. pentosus. Current microbial classifications based on 16S rRNA gene sequences, and also a few housekeeping genes [1-4] have several limitations. They begin with low phylogenetic resolution at various taxonomic ranks [5], followed by missing diversity because of primer mismatches [6], finally formation of corrupt tree topologies by drawing together various disparate groups [7]. Subsequently, we discovered the incidents that led to a change in the names of a few bacterial strains. It was a certain type of nucleotide changes to non-standard housekeeping genes such as rec A. Surprisingly, if the 99.9 % similarities found in the 16S rRNA right away it may be sequence blasted at nucleotide level and given a specific name. If not, above 99.0 % sequence similarity may be considered as another but, without considering the 16S rRNA. The dependence more on other than 16S rRNA sequence may be followed/considered/ ignored. These kinds of sudden changes in the name, causes lot of complications. The change in the name sometimes disqualifies the strain for human applications, as it has not listed in the local food safety guidelines. The name changes also created irreparable damage in commercializing the products. At the end, we should understand and accept that nothing changes the nature of the objects under classification the level of variations needs accounted for in any proposal. The classification scheme could be measured based on the number of people subscribe to it. Therefore, we may conclude that classification schemes of changing the names are rarely “right” or “wrong” but considered as simple and formal procedures to relax the complexity. This subsequently, provides a common acceptable nomenclature.

To Know More About Nutrition and Food Science International Journal 

Please click on: https://juniperpublishers.com/nfsij/index.php

For more Open Access Journals in Juniper Publishers

please click on: https://juniperpublishers.com/index.php