Characterization and Probiotic Potential of Lactobacillus plantarum Strains Isolated from Cheeses

Abstract

Ninety-eight Lactobacillus plantarum strains isolated from Italian and Argentinean cheeses were evaluatedfor probiotic potential. After a preliminary subtractive screening based on the presence of msa andbsh genes, 27 strains were characterized. In general, the selected strains showed high resistance tolysozyme, good adaptation to simulated gastric juice, and a moderate to low bile tolerance. The capacityto agglutinate yeast cells in a mannose-specific manner, as well as the cell surface hydrophobicity wasfound to be variable among strains. Very high b-galactosidase activity was shown by a considerablenumber of the tested strains, whereas variable prebiotic utilization ability was observed. Only tetracyclineresistance was observed in two highly resistant strains which harbored the tetM gene, whereasnone of the strains showed b-glucuronidase activity or was capable of inhibiting pathogens. Three strains(Lp790, Lp813, and Lp998) were tested by in vivo trials. A considerable heterogeneity was found amonga number of L. plantarum strains screened in this study, leading to the design of multiple cultures tocooperatively link strains showing the widest range of useful traits. Among the selected strains, Lp790,Lp813, and Lp998 showed the best probiotic potential and would be promising candidates for inclusionas starter cultures for the manufacture of probiotic fermented foods.