COMPARISON OF PROBIOTIC PROPERTIES OF LACTOBACILLUS PARACASEI AND LACTOBACILLUS PLANTARUM ISOLATED FROM TRADITIONAL SEMNAN CHEESE

Background and Aim:Probiotics are defined as live microorganisms, which when administered in adequate amounts, confer a health benefit on the host. In fact, the beneficial effects of probiotics are exerted by improving microbial balance. The acid and bile tolerances are two fundamental properties that indicate the ability of a probiotic microorganism to survive the passage through the gastrointestinal tract, resisting the acidic conditions in the stomach and the bile acids at the beginning of the small intestine. New probiotic strains should be resistant to the severe condition of human gastrointestinal tract.Methods:In this study, the probiotic ability of Lactobacillus paracasei and Lactobacillus plantarum isolated from traditional Semnan cheese was evaluated. At first, the ability of isolates to bile resistance and acid tolerance was determined by culturing in MRS broth previously adjusted to pH values (3.5, 4.5 and 5.5) and bile concentrations (0.3, 0.5 and 1%). Then comparing the bacterial growth was monitored by measuring absorbance with a spectrophotometer at 600 nm during 24 hours incubation at 37 C.Results:Based on the comparison of the growth outcomes, Lactobacillus plantarum showed better resistance to Lactobacillus paracasei in PH and different concentrations of bile salts (p<0.05).Conclusion:Therefore, the mentioned Lactobacillus can be considered as a native probiotic for simultaneous application with commercial cultures to increase the health of probiotic dairy products.

کلیدواژه ها:

Lactobacillus plantarum ، Lactobacillus paracasei ، Probiotic ، Traditional cheese