Title: Methods for improving survival of probiotics against harsh environments Abstract :
Probiotics are live microorganisms which pass through the gastrointestinal tract and survive the harsh environments of the GI tract tolerating low pH in stomach, bile salts, limited space preoccupied by the pathogens etc. Therapeutic benefits have led to an increase in the incorporation of probiotic bacteria such as lactobacilli and bifidobacteria in dairy products, especially fermented dairy products. Encapsulation techniques enhanced the survival of probiotic cultures compared to free cells in different dairy products stored for a longer periods. It also protects the bacteria from harsh conditions (low pH, antibiotics, bacteriocins, bile salt concentration etc) in the gut. Different coating materials for encapsulations for various bacterial cultures including probiotics has been a common practice for extending their storage life in vitro and also survivability in the GI tract in vivo to provide the health benefits to the consumers consuming different functional fermented dairy foods.
Title: Production of concentrated yoghurt culture using whey based media Abstract :
In this investigation, growth performance of yoghurt culture was studied in a developed whey based medium (WBM) for production of cultures biomass and preservation in concentrated dried form.Growth performances (K) of yoghurt cultures in WBM were 0.765 and 0.723 for S. thermophilus and L. bulgaricus. Culture biomass produced was harvested by centrifugation, re-suspended in freeze-drying medium followed by freeze drying. Viable counts of freeze dried cultures were 11-12 log cfu/ g. Dry culture was packed in storage vials and stored at -20±1°C and viable counts were in the range of 11 to 12 log cfu/g. Physiochemical, microbiological and sensory qualities of yoghurt prepared using concentrate preserved culture and fresh propagated culture were comparable under refrigeration conditions till 5 days of study.
Title: Probiotic lassi preparation and sensory evaluation using L. paracasei immobilized dry fruit pieces Abstract :
The objective of the study was to formulate and study sensory acceptability and probiotic cell count of fresh and stored lassi prepared using probiotic cells immobilized on two selected dry fruits. Free cells of the probiotic microorganism and cells immobilized in alginate beads were used for control lassi preparation. The organism used was L. Paracasei and the dry fruits selected for immobilization were figs and dates.Sensory evaluation (using modified Hedonic score card) of the fresh and stored products was carried out and L. paracasei count (on RCABV Agar) was also enumerated.
Title: Isolation and identification of phytate-degrading lactobacilli from indian cereal-based fermented milk product – “Raabadi” Abstract :
The present study on the isolation and characterization of potential phytate degrading lactobacilli from Raabadi was carried out. Twenty five samples of country made Raabadi collected from different villages of Rajasthan and Haryana in India were analyzed. Out of 40 lactobacilli isolates, nine were identified as phytate degrader, one was identified as Lactobacillus rhamnosus, five were identified as Lactobacillus fermentum and remaining three were identified as Lactobacillus brevis through phenotypic and genotypic characterization. These isolates are very much potential to degrade the phytate in cereal based fermented products.
Title: Evaluation of probiotic potential of lactic acid bacteria isolated from traditional fermented milks by in vitro study Abstract :
Probiotic potential of five lactic acid bacteria(Lactobacillus rhamnosus NK2, Lactobacillus casei NK9, Lactobacillus rhamnosus NK10, Lactobacillus pentosus M20 and Lactobacillus plantarum M22 ) was carried out by performing a battery of in vitro tests i.e. low pH tolerance, tolerance to high bile concentration, cell surface hydrophobicity, bile salt hydrolase and antimicrobial activity. These isolates were able to tolerate upto pH 2.0 for 3h and 0.5% oxgall upto 4hrs. Hydrophobicity against toluene and xylene was found in the range of 42.48% to 77.80% and 37.97% to 75.39%, respectively. Bile salt (0.5% sodium taurocholate) hydrolase activity was found only in L. plantarum M22. The antimicrobial activity was measured using cell free supernatant (CFS) and neutralized CFS (pH 7) against four indicator strains (Bacillus cereus, Listeria monocytogenes, Staphylococcus aureus and Salmonella typhi). All the isolates were able to producezone of inhibition with CFS depending on the indicator strains but with neutralized CFS,Lactobacillus rhamnosus NK2 was failed to inhibitS. typhi,L. casei NK9 was failed to inhibit Listeria monocytogenes, S. aureus and S. typhi while L. rhamnosus NK10, L. pentosus M20 and L. plantarum M22 couldn’t produce inhibition zone against Listeriamonocytogenes andS. aureus. L. plantarum M22 could be a potential probiotic isolate compared to others.
Title: Design, development and comparison of ethanol production from free and immobilized saccharomyces cerevisiae under stationary culture Abstract :
The aim of the present study is to design, develop and compare the production capacity and the difference in the yield of the ethanol by fermentation technology. The utility of the alcohol per annum is increasing day by day as the number of industries using ethanol as a solvent, pharmaceutical aid. Hence the production of ethanol by fermentation technology has triggered us to investigate the best way and method to produce ethanol of benefit of Pharmaceutical Industry. Method: The conventional method of production of alcohol was performed by aerobic batch type of fermentation: the yield was noted. The same production was performed by using immobilized yeast cells by gel entrapment technique. We produced ethanol by free and immobilized saccharomyces cerevisiae under stationary culture. Cane molasses was used as a sugar source for about (12 – 21%), medium pH (4-5.5). incubation temperature (250c-300c), volume of fermentation medium (200 – 350ml) and reuse of immobilized yeast cells. Result: Rate of ethanol production was maximal with immobilized yeast cells. The results indicate that 2gm vegetative cells of yeast on utilizing molasses at 15% sugar concentration with medium pH 4.5 at 30oC. Conclusion: Hence we conclude that the fermentation optimization and the yield value of popular organic solvent (ethanol) was studied and reported.
Title: ‘Chubitchi’- The native fermented rice beverage of the garos’ of west garo hills, Meghalaya Abstract :
TheWest Garo Hills is one of the largest districts of the state of Meghalaya located in the western part of the State with Tura being the district headquarters. They are inhabited by tribal dwellers, the majority of whom are Garo people whose staple cereal food is rice. Also home brewed fermented rice beverage plays an important role in the life of the rural tribal folks. This traditional beverage constitutes an integral part of their dietary culture and has strong socio-cultural importance among these ethnic people.The prowess of preparation of this beverage involves starter culture preparation using locally available medicinal plants and fermentation in earthen pots. Some rural villages where the fermented rice beverage is prepared were visited and the traditional process was observed and documented. This article reflects the expertise of the ethnic Garos’ who are unwittingly exploiting the natural microbial consortium in fermentation of this beverage.
Title: Antimicrobial activity of bioactive peptides derived from fermentation of soy milk by Lactobacillus plantarum C2 against common foodborne pathogens Abstract :
This study presents, antimicrobial activity of bioactive peptides derived from fermentation of soy milk along with their production by Lactobacillus plantarum C2 strain. Bioactive peptides are specific fragment of protein, can be released by fermentation, upon release they may act as antimicrobial, antioxidant, antihypertensive, immunomodulatory and hypocholesterolemic activities. LP C2 showed very good growth in soy milk by increasing their count and acidity significantly, consequently pH dropped. Ultrafiltration was used for the separation of peptides and their peptide contents analyzed by OPA assay. 10kDa fraction was found high in peptide (655.128±2.95 μg/ml). Antimicrobial activity of bioactive peptide fractions was checked by agar well diffusion method and found that 5 kDa showed highest activity against all the pathogens with highest inhibition against E.coli (12±0.57) followed by S. dysenteriae (11±0.57), L. monocytogenous (10±0.57) and B. cereus (10±0.57 mm). However it was observed that unfractionated sample high in antimicrobial activity, may be due to combined effect of all the fractions.