National Institute of Nutrition, India
Green leafy vegetables (GLVs) are pigment-rich and nutritionally relevant functional food sources with unique phytochemical constitution that includes carotenoids. Carotenoids and their geometric isomers protect cells from oxidation and cellular damages. Cooking processes that involve factors such as temperature, light and alteration in moisture content generally promote either isomerization (trans to cis form) or oxidative degradation of carotenoids to epoxides. Studies pertaining to the effect of cooking methods on dietary carotenoids and their geometric isomers are inadequate in Indian foods. The extent of carotenoid isomeration were evaluated in GLVs such as amaranth (Amaranthus gangeticus), spinach (Spinacia oleracea) and curry leaves (Murraya koenigii) subjected to domestic cooking methods of microwave, sautéing, pressure cooking and deep frying in oil for time durations of 8 and 12 minutes, either with and without lid covering. The isomers of carotenoids were quantified by high performance liquid chromatography (HPLC) using vydac column (RP-C-18) with 100% methanol for first 5 minutes and methanol: chloroform (96:4) for the subsequent run as gradient mobile phase. Tranʼs β-carotene content in amaranth ranged from 5525 to 6375 μg/100g upon boiling without lid and microwave cooking. 9-cis isomer of beta carotene is the predominant geometric isomer formed during cooking in all the GLV studied (Amaranth: 423 to 620, Spinach: 377 to 443, Curry leaves: 562 to 687 μg/100g). 13 cis isomers also formed in the processed GLV samples (22 to 375 μg/100g). 15 cis beta carotene was observed in few food samples during processing and not observed in some of the methods which processed. The retention percentage of all Trans and cis beta carotene was also studied. These isomers of beta carotenes were also for the precursors of Vitamin A. The changes in the contents of Trans and cis isomers of carotenes in GLVs in correlation to various cooking methods are discussed which would be valuable for food researchers, nutritionists and health practitioners in promoting nutritionally balanced diets and minimize vitamin A deficiency in Indian contest.
Keywords: GLV, Carotenoids, HPLC, Isomers
Dr. Sreenivasa Rao Jarapala is an Assistant Director at NIN, ICMR, India. He was completed his masters degree in Biochemistry from Andhra University and (PhD) from Osmania University, Hyderabad. He has published several research papers in reputed journals and he has presented his research findings in several National and International conferences and workshops. He received young scientist award (Sagarmal goenka) in 2012 and best research paper award in nutrition from USA in 2016. Presently he is working on tribal indigenous foods, plant secondary metabolites and heavy metals in Indian foods. His area of interest is carotenoids bio accessibility and bioconversion to vitamin A and nutrient retention in foods. He is a life member of NSI, SBCI, IDA, IIIS and several other nutrition relevant research bodies.
1Avinashilingam University for Women, India
2Sri Sarada college for Women, India
3The World Vegetable Center, Taiwan
Background: In India, the recent ICMR study revealed that the prevalence of diabetes (both known and newly diagnosed) in 4 regions of the country: 10.4 per cent in Tamil Nadu, 8.4 per cent in Maharashtra, 5.3 per cent in Jharkhand, and 13.6 per cent in Chandigarh (Anjana et al., 2011). High prevalence of prediabetes observed in many South Asian countries highlights a potential indicator of further progression of the diabetic epidemic in the region. Unless appropriate action is taken, this will place an economic burden. Hence a food based approach was planned to reduce the incidence of prediabetics. The main aim of the present study was to investigate the hypoglycemic effect of bitter gourd (Mormordica Charantia L.) among prediabetics.
Materials and Methods: A single blinded, placebo-controlled, randomized, cross-over designed intervention study was conducted with freeze dried bitter gourd powder (2.5 g) to find out its hypoglycemic effect. In the first phase Group 1 (AB) started the bitter gourd juice (A) intervention followed by placebo(B), while the Group 2 (BA) started the supplementation with placebo(B) followed by bitter gourd(A). The intervention continued for a period of eight weeks. Between the two arms, 4 weeks were left as wash-out period. This is to minimize the carry-over effect of one phase to the other. Cross over was done after this washout period.
Results: The mean initial fasting blood glucose level of prediabetics in AB group was 110.66 mg/dl which got reduced significantly (p<0.01) to 99.86 mg/dl at the end of bitter gourd intervention. In the case of BA group the placebo treatment did not bring forth any appreciable change in FBG where as the bitter gourd treatment was found to have a significant (p<0.01) impact. No serious adverse effects were observed.
Conclusions: The present study proves that the consumption of bitter gourd juice prepared with 2.5 g freeze-dried bitter gourd powder (50g of the vegetable) reduced the fasting blood glucose and total cholesterol level among the prediabetics.
Keywords: Hypoglycemia, prediabetes, bitter gourd, diabetes.
Dr. M. Amirthaveni is a Professor and Head, Department of Food Science and Nutrition and has 42 years of teaching and research experience in Avinashilingam University, Coimbatore. She has completed Post Doctoral Fellowship training at Asian Vegetables Research and Development Centre (AVRDC), Taiwan during 1998. She has guided about 8 Ph.D. dissertations and 64 post graduate students. To her credit, she has completed 4 international research projects and 3 national projects. She has authored 2 books and published 20 international and 60 national level articles in refereed journals. Has also participated and presented papers in conferences at Japan, Tanzania and Taiwan. She is appointed as JRM team member for the Midday Meal Evaluation Committee by Ministry of Human Resource Development, Government of India. Member in various committees and boards of national standards like Nutrition Society of India, Home Science Association of India and Indian Dietetic Association.
University of Maryland, USA
The United States Food Safety Modernization Act (FSMA) was signed into law in 2011. FSMA aims to better protect public health by strengthening the food safety system. It focuses more on preventing food safety problems rather than relying primarily on reacting to problems after they occur. For the first time, the US Food and Drug Administration (FDA) will require comprehensive, science-based preventive controls across the food supply. The law directs FDA to develop a comprehensive plan to expand the capacity of foreign governments and their industries. One component of the plan is to address training of foreign governments and food producers on U.S. food safety requirements. The Joint Institute for Food Safety and Applied Nutrition (JIFSAN) at University of Maryland (UMD) was established by the university and FDA in 1996. The UMD and FDA partnership has provided a dynamic program that integrates research, education and outreach that enhance FDAʼs ability to address safety concerns and public health issues related to foods. JIFSAN has also developed and delivered education and training programs to support food safety capacity building in more than 50 countries. These programs include food safety best practices at production, risk analysis, preventive controls and hands-on laboratory techniques. Over 8,000 food safety professionals have participated in the programs. JIFSAN will continue to strengthen the established programs and work on new initiatives to be identified that are important to support FSMA in enhancing science-based preventive control standards to strengthen the food safety system and improve worldwide health.
Dr. Jianghong Meng is Director, Joint Institute for Food Safety & Applied Nutrition (JIFSAN); Acting Director, Center for Food Safety and Security Systems; and Professor, Department of Nutrition and Food Science, University of Maryland, College Park. Prof. Meng received his Ph.D. from University of California, Davis. He is an internationally renowned expert in microbial food safety, and has authored over 180 publications. He has made a major impact on food safety globally through his strong leadership at JIFSAN (www.jifsan.umd.edu), an FDAʼs Center of Excellence. He has built strong partnerships in expanding JIFSANʼs food safety training programs both locally and globally.
Charles Sturt University, Australia
The incidence of food-borne diseases has been increased over the last decade and has become a major public health worldwide. Among 31 identified food-borne pathogens, non-typhoidal Salmonella and Campylobacterspp. are the most common detected bacteria in food-borne incidents. Poultry meat, eggs and products contaminated with Salmonella and/or Campylobacter are the major source of food-borne diseases in humans. The aim of this study was to develop reliable and rapid diagnostic tests that can detect and differentiate Salmonella seroptypes and Campylobacter jejuni from Campylobacter coli without requiring DNA sequencing. Specific primers were used to amplify targeted genes of different Salmonella and Campylobacter reference strains and clinical isolates from commercial poultry farms. PCR products were subjected to high-resolution melt curve analysis and Salmonella or Campylobacter isolates were differentiated based on their HRM curves. Analysis of the nucleotide sequences of the amplicons from selected isolates confirmed that each melting curve profile was related to a unique DNA sequence. The relationship between Salmonella or Campylobacter reference strains and tested specimens was also evaluated using a mathematical model without requiring visual interpretation of HRM curves. In addition, the potential of the PCR-HRM curve analysis was evaluated for genotyping of additional Salmonella isolates from different avian species or human Campylobacter isolates. The findings indicate that PCR followed by HRM curve analysis provides a rapid and robust technique for genotyping of Salmonella and Campylobacter isolates in about 6 hours. Applications of PCR-HRM in identification of other pathogens, important in food safety will be discussed.
Keywords: Salmonella, Campylobacter, PCR, high resolution melting curve analysis, genotyping
Dr. Ali Ghorashi is a senior lecturer in Animal production and Health at the Charles Sturt University, Australia. He received his DVM degree from Tehran University and a Ph.D. from James Cook University in Australia. He worked at National Institute of Genetic Engineering and Biotechnology and moved to Melbourne University as a research fellow before joining Charles Sturt University. Dr. Ghorashi is a member of editorial board of five international scientific journals as well as professional organisations. His research interests are molecular diagnosis and genotyping of veterinary pathogens and molecular epidemiology of infectious diseases.