Abstract: Vomitoxin, also known as DON, is a secondary metabolite produced by several Fusarium sp. In order to select microorganisms capable of degrading DON, high-throughput sequencing was used to analyze DON-degrading bacteria in bacterial consortia. In this study, bacterial consortium LG-6 with DON-degrading capacity was obtained from soil, and it was found that the effect varied depending on the dilution ratio of the bacterial consortium. LG-6 diluted by a factor of 10-7 (denoted as LG-6-7) but not 10-8 (denoted as LG-6-8) could completely degrade DON. The analysis of microbial diversity demonstrated that LG-6-7 included Pseudochrobactrum, Pseudomonas, Delftia, Devosia, and Achromobacter, while LG-6-8 included only Pseudochrobactrum and Achromobacte, indicating that Pseudomonas, Devosia and Delftia are essential for the degradation of DON. In addition, DON was completely degraded within 48 h by a bacterial consortium of Pseudomonas sp. B6-24 and Devosia A6-243. The optimal culture conditions for the bacterial consortium were 37 ℃, pH 7.0, and MMT medium. Moreover, microbial enzymes from the consortium were responsible for the degradation of DON. In conclusion, a bacterial consortium of Pseudomonas sp. B6-24 and Devosia A6-243 can degrade DON completely, which will lay a foundation for the research and development of biological detoxifying agents for vomiting toxin.

Key words: deoxynivalenol; detoxification; microbial diversity analysis; Pseudomonas; Devosia