In vitro pH tolerance, bile salt resistance and antimicrobial activity of lactobacillus plantarum isolated from crossbred cattle

This research was done to evaluate the characteristics and probiotic potential of lactic acid bacteria (LAB) isolated from the small intestine of ten three year-old male Ongole crossbred cattle. Ten-centimeter samples were obtained from each small intestine, wastes were removed then samples were placed in sterile sample bottles, and immediately taken to the laboratory for bacterial isolation. The LAB isolates were subjected to low pH tolerance (pH 2 and 4), bile salt resistance, and antimicrobial activity against enteric pathogens Staphylococcus aureus and Eschericia coli. Biochemical assay indicated that isolate was gram positive, rod-shaped, catalase negative, and capable of fermenting glucose, mannitol, xylose, rhamnose, sucrose, lactose, arabinose, raffinose and sorbitol. Biochemical and morphological identification suggests that the isolate was Lactobacillus plantarum WPL 117 (strain number of control indicator organisms was Lactobacillus plantarum ATCC 14917). This isolate was able to survive at low pH (2 and 4), tolerated 0.3% bile salts, and capable of inhibiting S. aureus and E. coli. Thus, this isolate can be considered a probiotic candidate for further study.