Identification and characterization of Bacillus coagulans strains for probiotic activity and safety

Four Bacillus coagulans strains were isolated from plant-based sources and screened for heat resistance, in vitro probiotic properties and toxicological characteristics and compared with B. coagulans GBI-30, 6086. These strains survived high temperatures and low pH, were resistant to bile and lysozyme, were able to produce biofilm, had antimicrobial activity, and were antibiotic-sensitive. All strains had the properties of adhesion, auto- and co-aggregation, although the level of each varied and with incubation time. The safety of these strains was confirmed as no enterotoxin genes (bceT, ces, entFM and cytK) were present and enterotoxins (Hbl, and nhe) were not detected. Hemolytic activity and lecithinase production did not occur. These results indicate that isolated B. coagulans strains have potential probiotic characteristics and could be used as candidate probiotics in heat-treated vegan probiotic food products.