Antifungal properties and AFB1 detoxification activity of a new strain of Lactobacillus plantarum.

Aflatoxin B1 is the most toxic mycotoxin and has strong carcinogenicity. In this study, coumarin was employed as the sole carbon source to isolate the microorganisms that had AFB1 detoxification activity. Among106 strains isolated from fermented foods, one potential strain was identified as Lactobacillus plantarum based on 16S rDNA sequence. Removal ratio of AFB1 was 89.5%, inhibitory ratio to A. flavus growth was 42.8% and inhibitory ratio to A. flavus spores growth was as high as 100%. Coumarin utilization indicated that the AFB1 could be decomposed by the strain. The strong antifungal ability against A. flavus growth and spores growth revealed that AFB1 secretion could be highly inhibited by the strain. In addition, High Performance Liquid Chromatography analysis indicated that fermentation supernatant of the strain could degrade AFB1. Scanning Electron Microscopy and Transmission Electron Microscopy indicated that the strain had a strong resistance to AFB1 and had ability to bind AFB1 on the strain surface. Possible detoxification pathway to AFB1 was proposed. Therefore, the strain with high antifungal, antimycotoxigenic abilities might have great potential and immense value in detoxifying AFB1. The use of the strain might be a promising biocontrol strategy to detoxify AFB1.