一株氯嘧磺隆高效降解菌分离鉴定及降解条件优化

Isolation and identification of a chlorimuron-ethyl-degrading bacterium and optimization of its degradation conditions

采用富集培养方法从氯嘧磺隆生产单位排污口处污泥中分离得到一株能降解氯嘧磺隆细菌,命名为D310-5。通过对该菌株形态特征观察,生理生化特性和16S r DNA序列分析,将菌株D310-5鉴定为肠杆菌属(Enterobacter sp.)。采用响应面分析方法探究底物浓度、温度、p H和培养时间对菌株D310-5降解氯嘧磺隆影响,优化菌株D310-5对氯嘧磺隆降解条件。结果表明,菌株D310-5最佳降解条件为底物浓度101.57 mg·L-1,温度30.25℃,p H 6.63,培养时间5 d。在最佳条件下,菌株D310-5对氯嘧磺隆降解率为87.57%。

A chlorimuron-ethyl-degrading strain D310-5 was isolated from the sludge samples which derived from chlorimuron-ethyl production factory by the method of enrichment culture. Based on morphology, physiological and biochemical characteristics, 16 S r DNA sequence analysis, strain D310-5 was identified as Enterobacter sp. The effects of substrate concentration, temperature, p H and culture time on the chlorimuron-ethyl degradation by strain D310-5 were optimized using a response surface methodology（RSM）. The results showed that the optimal chlorimuron- ethyl degradation conditions were substrate concentration101.57 mg·L^-1, temperature 30.25 ℃, p H 6.63, culture time 5 d. Under the optimal degrading conditions, the chlorimuron-ethyl degradation efficiency of strain D310-5 was 87.57%.