Screening, identification and antagonistic effect of antagonistic bacteria JTFM1001 against aflatoxin contamination in corn

Aflatoxin is a strong carcinogenic and toxic fungal toxin produced by Aspergillus flavus and other Aspergillus species, and can seriously threaten the health of consumers, thus becoming a global concern. Corn, as an important oil and economic crop, is highly susceptible contaminated by aflatoxin. In this study, antagonistic bacteria with strong inhibitory effect on aflatoxin were screened to provide support for the treatment aflatoxin contamination control in corn. Ten strains which have strong antagonistic effects against A. flavus were isolated from healthy corn from different corn producing areas in China. Among them, the antagonistic bacteria JTFM1001 through corn kernels in vivo and field experiment, the inhibition effect of aflatoxin contamination reached above 70% and 55%, respectively. And the strain was identified as Bacillus subtilis based on its morphological, physiological and biochemical characteristics and phylogenetic analysis of 16S rDNA. In addition, our data showed that it can colonize in the rhizosphere and survive for a long time, forming the dominant flora, with broad application prospect. Finally, we were surprised to find that the antibacterial metabolites secreted by the antagonistic bacteria was one of the mechanisms of its inhibition of A. flavus and aflatoxin. This will provide us with new ideas and perspectives on the effective prevention and control of aflatoxin contamination in corn and corn oil.