Asian Journal of Research in Biosciences

In this study thirteen lactobacilli isolates possessing probiotic characteristics such as acid and bile tolerance were screened out of forty Lactic Acid Bacteria (LAB) isolates which were obtained from fifteen domestic dahi samples. These acid and bile tolerant lactobacilli isolates further, were identified phenotypically and genotypically as Lb. rhamnosus (5 Nos). Lb.fermentum (3 Nos), Lb. plantarum (3 Nos) and Lb. delbrueckii ssp. bulgaricus (2 Nos). The identified cultures were subjected for the antibiotic test using the disc diffusion technique against Penicillin (10μg), Gentamycin (10 μg), Streptomycin (10 μg), Chloramphinicol (10 μg), Kanamycin (30 μg) Erythtomycin (15 μg) and Bacitracin (10 μg). All the five strains of Lb. rhamnosus strains were susceptible to all the seven antibiotics tested as they showed more than 10 mm diameter inhibitory zone. Similarly all the three strains of Lb. plantarum, Lb. fermentum and Lb. delbruckii ssp. bulgaricus were susceptible to all the antibiotics to varying degrees. In this study the results clearly demonstrate the susceptible nature of the probiotic Lactobacilli isolates against the commonly used antibiotics.