Probiotic properties of lactobacillus isolated from traditional milk and yoghurt of Babol and their antimicrobial effects against Salmonella enteritidis H7

Introdution: Today, probiotics are known to be effective in preventing the spread of many infectious diseases. Probiotic are living microorganisms that will be beneficial for the health of the host when used in adequate amounts. The purpose of this study was to investigate the probiotic properties of Lactobacillus isolated from traditional milk and yogurt. Methods: Probiotic properties of five Lactobacillus strains isolated from traditional milk and yoghurt of Babol including L. plantarum M19-1, L. paralimentarius M4-3, L. paracasei M18-1, L. paracasei Y8-1, L.paracasei Y1-3 and L. fermentum Y2-2 were studied. The inhibitory effect of these strains against Salmonella enteritidis H7 was measured. These strains also investigated for antibiotic susceptibility, resistance to acidic conditions, resistance to bile salts, and hemolysis. Results: The highest inhibitory effect was observed by Y1-3 strain with a mean diameter of 14 mm. In acid tolerance test at pH 2.5, M18-1 strain had the highest resistance, which its colonies were countable after three hours. Strains M19-1 showed the highest resistance to bile (MRS broth contains 0.3% bile) with Cinh 0.26. None of the strains had hemolysis activity. Conclusion: Lactobacillus strains with good inhibitory effects against Salmonella enteritidis could be isolated from milk and yogurt, which can be used as a probiotic candidate for the prevention or treatment of this bacterial infection, but further studies are needed