Isolation and Characterization of Brevibacillus parabrevis S09T2, a Novel Ochratoxin A-Degrading Strain with...

Ochratoxin A (OTA), a fungal secondary metabolite, is frequently detected in grains, herbal products, and other agricultural commodities, posing potential food safety risks. Among existing detoxification strategies, biological degradation is considered both specific and environmentally sustainable. In this study, a novel OTA-degrading bacterium, Brevibacillus parabrevis S09T2, was isolated from soil using OTA as the sole carbon source. The strain exhibited no hemolytic activity and carried no virulence or antibiotic resistance genes, indicating a favorable safety profile. S09T2 efficiently degraded OTA, removing over 93% of 5-8 μg/mL OTA within 24 h at 37 °C, and almost completely degrading OTA concentrations up to 10 μg/mL within 72 h. UPLC-HRMS analysis identified ochratoxin α (OTα) and phenylalanine as the only degradation products, confirming detoxification via amide bond hydrolysis. The intracellular enzyme responsible for this reaction displayed notable thermostability, achieving near-complete degradation of 1 μg/mL OTA at 50 °C within 6 h. Moreover, the cell lysate significantly reduced OTA levels in Plumeria rubra extract, a widely consumed functional food, demonstrating applicability in complex food matrices. Collectively, these findings highlight S09T2 as a promising candidate for OTA detoxification and support its potential use in food and feed safety applications.