EVALUATION OF ANTIMICROBIAL ACTIVITY OF PROBIOTIC BACTERIA ISOLATED FROM DIFFERENT NATURAL AND COMMERCIAL PRODUCTS

V. Asha Ranjani*, G. Tulja Rani, M. Sneha, N. Bhuvaneshwari and V. Vengal Reddy

ABSTRACT

Probiotics are defined as live microorganisms which when consumed in a sufficient amount could confer a health benefits. Probiotics are made of good live bacteria and yeast that naturally living in your body you constantly have both good and bad bacteria in body, when you get any infection, there is more bad bacteria knocking your system out of balance. Probiotics shows antimicrobial, anti-oxidant, and recently discovered that probiotics also contains anti-fungal property they also inhibit the growth of fungus.(Lactobacillus rhamnoses). Commonly claimed benefits of probiotics include the decrease of potentially pathogenic gastrointestinal microorganisms the reduction of gastro-intestinal discomfort, strengthening of immune system, improvement of skin function improvement of bowel regulator resistance to pollen allergens decrease in body pathogens the protection of DNA maintaining the stomach health when receiving antibiotics etc. Present paper discuss about isolation of probiotic bacteria from different natural sources fruits and vegetables kiwi, cabbage and capsicum and commercial sample like yoghurt etc. A total of four samples (kiwi, yoghurt, capsicum and cabbage) samples were collected from the local market. Fruit sample was inoculated into 100 ml of sterile MRS broth and incubated at 370C and the growth of isolates were sub cultured on nutrient agar plates and kept for incubation. After incubation, colonies were randomly selected, picked up and purified for further characterization. Then the isolates were screened for physiological characterization and biochemical characterization. Physiological characterization studies were performed at different temperature, pH, NaCl concentration. Isolates were exhibited growth at various conditions. Biochemical characterization were performed for catalase activity, carbohydrate fermentation test, arginine hydrolysis, starch hydrolysis citrate utilization and urea utilization. The antimicrobial properties of the probiotic bacteria were determined using agar well diffusion and the disc diffusion method using Bacillus subtills. Probiotic isolates exhibits antimicrobial activity for Bacillus subtilis.

Keywords: Probiotic bacteria, Physiological characterization, Biochemical characterization, MRS broth, Citrate utilization test, Antimicrobial studies.