Biological detoxification of zearalenone by Aspergillus niger strain FS10

Zearalenone (ZEN) contamination of corn and cereal products is a serious health hazard throughout the world and its elimination by microbial methods is now being widely examined. In this study, an Aspergillus niger strain, FS10, isolated from Chinese fermented soybean, was shown to reduce levels of ZEN in corn steep liquor (CSL). Spores, mycelium and culture filtrate of the strain FS10 were tested for their ability to remove ZEN. The results indicated that strain FS10 could remove 89.56% of ZEN from potato dextrose broth (PDB) medium. Mycelium and culture filtrate decreased the ZEN content by 43.10% and 68.16%, respectively. The contaminated corn steep liquor initially contained ZEN 29 μg/ml, 60.01% of which could be removed by strain FS10. To demonstrate the loss of toxicity in vivo, the culture filtrate incubated with the contaminated corn steep liquor for 48 h was administered to rats. The results indicated that the contaminated corn steep liquor severely damaged liver and kidney tissue. Rats administered with contaminated corn steep liquor treated with the strain FS10 culture filtrate showed significantly less severe liver and kidney damage, and organ index values were comparable to the non-ZEN-exposed control (p<0.05). Our study suggests an effective approach to reduce the hazards of ZEN in corn steep liquor.