Shanmugasundaram Balasubramanian, Singh Vijay Kumar, Shrestha Shrijana, Sarkar Sajib Kumar, Jeevaratnam Kadirvelu, Koner Bidhan Chandra

Coconut oil and sesame oil are commonly used in South India for frying foods. On heating, edible oils form hazardous chemicals. This study explores the effect of consumption of unheated and thermally-altered sesame and coconut oils on coronary artery disease (CAD) risk factors in Wistar rats. Thirty Wistar albino rats were randomly divided into five groups (n=6/group). Group I (Control) was fed only chow, Group II: chow + unheated sesame oil, Group III: chow + heated sesame oil, Group IV: Chow + unheated coconut oil, Group V: chow + heated coconut oil. After eight weeks of treatment, serum lipid profile, hs-CRP, leptin, glucose, insulin, HOMA-IR, TNF-α, IL-6 and plasma homocysteine and fibrinogen levels were estimated. Rats in Group II showed a significant decrease in serum cholesterol, LDL-c, TNF-α, hs-CRP, insulin, and HOMA-IR but a significant increase in HDL-c, Group III showed opposite effects on these parameters, except that it decreased serum triglycerides level. Group IV and V did not show any significant effect on stated parameters. We conclude that consumption of unheated sesame oil gives protective effects against the CAD. Thermally altered sesame oil increases the CAD risk. Unheated and thermally altered coconut oil did not show any significant effect. Hence, we recommend that sesame oil better be used for dressing the food and coconut oil for frying.

Optimization of nutritional and non-nutritional factors involved for production of antimicrobial compounds from Lactobacillus pentosus SJ65 using response surface methodology

Bacteriocins from lactic acid bacteria are ribosomal synthesized antibacterial proteins/ peptides having wide range of applications. Lactobacillus pentosus SJ65, isolated from fermented Uttapam batter (used to prepare south Indian pan cake), produces bacteriocin having a broad spectrum of activity against pathogens. Optimization studies are of utmost important to understand the source of utilization and the conditions to enhance the production of metabolites. In the present study, an attempt was made to identify the parameters involved for maximal production of antimicrobial compounds especially bacteriocin from the isolate L. pentosus SJ65. Initially, optimal conditions, such as incubation period, pH, and temperature were evaluated. Initial screening was done using methodology onevariable-at-a-time (OVAT) for various carbon and nitrogen sources. Further evaluation was carried out statistically using Plackett-Burman design and the variables were analyzed using response surface methodology using central composite design. The optimum media using tryptone or soy peptone, yeast extract, glucose, triammonium citrate, MnSO4, dipotassium hydrogen phosphate and tween 80 produced maximum bacteriocin activity.

Molecular characterization of lactobacilli isolated from fermented idli batter

Lactic acid bacteria are non pathogenic organism widely distributed in nature typically involved in a large number of spontaneous food fermentation. The purpose of this study was to characterize the bacteriocinogenic lactobacilli from fermented idli batter which can find application in biopreservation and biomedicine. Eight most promising lactobacilli were chosen from twenty two isolates based on their spectrum of activity against other lactic acid bacteria and pathogens. The eight lactobacilli were characterized based on the various classical phenotypic tests, physiological tests and biochemical tests including various carbohydrate utilization profiles. All isolates were homo fermentative, catalase, and gelatin negative. Molecular characterization was performed by RAPD, 16S rRNA analysis, 16S ARDRA, and Multiplex PCR for species identification. RAPD was carried out using the primer R2 and M13. Five different clusters were obtained based on RAPD indicating strain level variation. 16S rRNA analysis showed 99 to 100% homology towards Lactobacillus plantarum. The restriction digestion pattern was similar for all the isolates with the restriction enzyme AluI. The subspecies were identified by performing Multiplex PCR using species specific primer. Among the five clusters, three clusters were clearly identified as Lactobacillus plantarum subsp. plantarum, Lactobacillus pentosus, and Lactobacillus plantarum subsp. argentoratensis.