Antimutagenic potential of four strains of bacteriaof the genus <i>Lactobacillus</i>

BACKGROUND: Bacteria of the genus Lactobacillus possessing a number of positive properties on the human body are a promising source for the creation of functional nutrition. The study of antimutagenic activity of lactobacilli will substantiate the use of these bacteria to prevent the effects of genotoxic environmental factors. AIM: To comparative analysis the antimutagenic potential of four Lactobacillus strains. MATERIALS AND METHODS: Four bacterial strains Lactobacillus casei 3184, L. casei MB, L. plantarum AB, L. plantarum B578 were used in this work. The antimutagenic activity of cells suspension and supernatant of Lactobacillus culture was evaluated using Ames test. RESULTS: The supernatant of L. plantarum B578 in the stationary growth phase most effectively suppressed the mutagenic effect of sodium azide (45.6%) and 2-nitrofluorene (43.5%). Substantial antimutagenic activity was also observed for the cell suspension of the strains L. casei 3184 and L. plantarum AB in the exponential growth phase against sodium azide(40.8% and 39.9%, respectively), and for the supernatant of these strains in the stationary growth phase against 2-nitrofluorene (39.8% and 37.5%, respectively). L. casei strain MB did not significantly reduce the effect of known mutagens: the antimutagenic activity of all tested samples for this strain in different growth phases ranged from 15.9% to 23.4% against sodium azide, and from 15.6% to 28.5% against 2-nitrofluorene. CONCLUSION: Analysis of the results obtained suggests that the antimutagenic effect of L. casei 3184 and L. plantarum AB strains against sodium azide is due to direct binding of the mutagen by lactobacilli cells, and that of L. plantarum B578 strain — by exometabolites accumulating in the tested culture media during the stationary growth phase. Reduction of 2-NF mutagenicity by L. casei 3184, L. plantarum AB and L. plantarum B578 strains can also be associated with direct binding of the mutagen, with inhibition of biotransformation enzymes of this compound, and with the antioxidant effect of exometabolites of lactobacilli strains. The data obtained emphasize the dependence of the antimutagenic potential of lactobacilli on the growth phase and indicate the promising application of the strains L. plantarum B578, L. casei 3184 and L. plantarum AB to reduce the negative effects of genotoxic agents.