Properties of postbiotics produced by probiotics: antimicrobial, antioxidant activities and production of vitamins, organic acids

Abstract

Abstract The current study was conducted to determine and investigate the antimicrobial, antioxidant activity, vitamins, organic acid and short-chain fatty acid composition of postbiotics produced by some probiotics. In this study, the antimicrobial activity of all postbiotics from tested probiotic strains showed zones of inhibition against most indicator strains, but with different diameters. The results show that L. acidophilus and L. helveticus had the largest inhibitory effects on pathogenic bacteria and fungi. The results also show that the postbiotics have antioxidant activity. It was observed that the L. plantarum strain had the highest antioxidant activity, followed by L. rhamnosus GG and B. bifidum. The results indicated that postbiotics produced by various strains contain many organic acids in different concentrations. In conclusion, different compounds detected in the postbiotics of the probiotic strains used in this study are in preparation for the next research on their nutritional evaluation to identify the best strains for application in functional dairy products.