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

Aflatoxin B-1 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 AFB(1) detoxification activity. Among106 strains isolated from fermented foods, one potential strain was identified as Lactobacillus plantarum based on 16S rDNA sequence. Removal ratio of AFB(1) 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 AFB(1) could be decomposed by the strain. The strong antifungal ability against A. flavus growth and spores growth revealed that AFB(1) secretion could be highly inhibited by the strain. In addition, High Performance Liquid Chromatography analysis indicated that fermentation supernatant of the strain could degrade AFB(1). Scanning Electron Microscopy and Transmission Electron Microscopy indicated that the strain had a strong resistance to AFB(1) and had ability to bind AFB(1) on the strain surface. Possible detoxification pathway to AFB(1) was proposed. Therefore, the strain with high antifungal, antimycotoxigenic abilities might have great potential and immense value in detoxifying AFB(1). The use of the strain might be a promising biocontrol strategy to detoxify AFB(1).