Investigation of probiotic properties of lactobacilli bacteria isolated from human gastrointestinal tract

Abstract

In this study, the probiotic characteristics of Lactobacillus which were taken from the stool samples of 30 children, aged between 5 and 15 years, were studied. The stomach medium (low pH) and bile salt tolerance, bile salt hydrolysis activity, antagonistic activity and cholesterol assimilation quantity of Lactobacillus strains were determined. It was defined that on the whole Lactobacillus strains were resistant to high acidity (pH 2.0-2.51 and sensitive to high levels of bile salt 1% 1.00 Oxgall), there was no bile salt hydrolysis activity, they were resistant to vancomycin, teicoplanin and bacitracin and had antagonistic effects on pathogenic bacteria. It was noted that only L. curvatus L26 strain, which produced bacteriocin, had a general antagonistic effect; was indulgent to gastric acid and bile salt; and in different bile salt medium assimilated cholesterol at a high degree 115.22-25.42 mu g/ml). At the same time, the fact that L. curvatus L26 had beta-glucuronidase digesting prebiotics and beta-galactosidase digesting lactose is one of its most significant probiotic properties. In the light of this information, our opinion is that L. curvatus L26 can involve potential probiotic characteristics.