Detoxification of Aflatoxin B1 by a Potential Probiotic WF2020.

Microbial degradation is considered as an attractive method to eliminate exposure to aflatoxin B1 (AFB1), the most toxic mycotoxin that causes great economic losses and brings a serious threat to human and animal health, in food and feed. In this study, WF2020, isolated from naturally fermented pickles, could effectively degrade AFB1 ranging from 1 to 8 μg/ml, and the optimum temperature and pH value were 37-45°C and 8.0, respectively. Moreover, WF2020 was considered to be a potential probiotic due to the synthesis of active compounds, absence of virulence genes, susceptibility to various antibiotics, and enhanced lifespan of . Extracellular enzymes or proteins played a major role in AFB1 degradation mediated by WF2020 into metabolites with low or no mutagenicity and toxicity to . AFB1 degradation by the cell-free supernatant was stable up to 70°C, with an optimal pH of 8.0, and the cell-free supernatant could still degrade AFB1 by 37.16% after boiling for 20 min. Furthermore, WF2020 caused a slight defect in fungal growth and completely inhibited AFB1 production when co-incubated with . Additionally, WF2020 suppressed the expression of 10 aflatoxin pathway genes and 2 transcription factors ( and ), suggesting that WF2020 might inhibit AFB1 synthesis in . These results indicate that WF2020 and/or its extracellular enzymes or proteins have a promising potential to be applied in protecting food and feed from AFB1 contamination.