Unlocking the Potential of Bacillus subtilis: A Comprehensive Study on Mycotoxin Decontamination, Mechanistic Insights, and Efficacy Assessment in a Liquid Food Model

Mycotoxin detoxification by microorganisms offers a specific, economical, and environmentally sustainable alternative to physical/chemical methods. Three strains of <i>B. subtilis</i>, isolated from poultry farm environments and recognized by EFSA as safe in animal nutrition for all animal species, consumers, and the environment, were screened for their ability to remove mycotoxins. All of them demonstrated mycotoxin-dependent removal efficacy, being very effective against ZEA and its analogues (α- and β-ZOL, α- and β-ZAL, and ZAL) achieving up to 100% removal within 24 h under aerobic, anaerobic, and restrictive growth conditions with toxins as the sole carbon source. ZEA removal remained effective across a wide range of pH values (5-8), temperatures (20-40 °C), and at high toxin concentrations (up to 10 µg/mL). Additionally, up to 87% ZEA removal was achieved after 48 h of incubation (30 °C) of the strains in a contaminated liquid food model containing 1 µg/mL of the toxin. Mechanistic studies suggest that ZEA detoxification involves metabolic processes rather than physical adsorption or entrapment into bacterial cells. Enzymatic activities within the bacterial cells or associated with their cell walls likely play a role in the metabolization of the toxin. Interestingly, it has been observed that growth conditions and culture media can influence the metabolization and/or conjugation of the toxin, which can result in the production of various metabolites. Further investigation is needed to identify these metabolites and assess their safety.