降解黄曲霉毒素B_1芽孢杆菌的筛选与鉴定

Screening and Identification of Bacillus Strain for Degradation of Aflatoxin B_1

本研究以香豆素为唯一碳源进行黄曲霉毒素B_1(AFB_1)降解菌的筛选,从花生地土壤中分离出高效降解AFB_1的菌株A3042。研究该菌的上清液、菌悬液、胞内液对AFB_1降解特性。结果表明,菌株A3042能高效降解AFB_1,其胞外上清液、菌悬液和胞内液分别降解91. 7%、11. 4%和7. 6%的AFB_1,表明起降解的活性物质主要位于胞外液。综合其形态学特征、生理生化特征和16S rRNA基因分析,鉴定菌株A3042为蜡样芽孢杆菌(Bacillus cereus),命名为Bacillus cereus A3042。本研究为食品和饲料中AFB_1的生物降解提供菌种资源。

In this study, the bacterial strain A3042 was isolated from the soil in Qingdao by screening with coumarin as the only carbon source. It could efficiently degrade aflatoxin B 1（AFB 1）.The degradation characteristics were studied in the supernatant, suspension and intracellular fluid. The results showed that the extracellular supernatant, bacterial suspension and intracellular fluid of the strain A3042 could respectively degrade 91.7%, 11.4% and 7.6% of AFB 1, indicating that the main biodegradable active substance was in extracellular fluid. The strain A3042 was identified as Bacillus cereus and named as Bacillus cereus A3042 using morphological, physiological and biochemical features and 16S rRNA gene analysis. This study provided strain resource for the biodegradation of AFB 1 in food and feed.