咪唑乙烟酸降解菌的分离、鉴定及其降解特性研究

Isolation and Identification of Imazethapyr Degradable Bacteria and Its Degradation Characteristics

从生产咪唑乙烟酸化工厂排污口的污泥和长期施用咪唑乙烟酸的混合土壤中分离到1株能降解咪唑乙烟酸的细菌.该菌株在72 h内对500 mg/L的咪唑乙烟酸降解率达到90%以上.pH为5时,500 mg/L的咪唑乙烟酸72 h内可全部降解,而pH 8和pH 9条件下,72 h咪唑乙烟酸的降解率仅为50%左右,酸性条件比碱性条件更适合降解菌的生长.25℃和30℃条件下,降解菌对咪唑乙烟酸的降解效率较高.25℃,pH 5是降解菌对咪唑乙烟酸降解的最佳条件.从形态特征、生理生化特性及16S rRNA序列分析鉴定该菌株属于产碱菌属.

One strain of imazethapyr degradable bacteria was isolated from the mixture of imazethapyr production factory＇s sludge and the soil that was contaminated with imazethapyr for a long time. The strain could degrade imazethapyr more than 90% within 72 h when it grew in 500 mg/L imazethapyr condition. When pH was 5, the bacteria could degrade all the imazethapyr of 500 mg/L in 72 h, but when pH was 8 and 9, only 50% imazethapyr was degraded which showed acid condition was more compatible than that of alkalescency for this bacteria growing. The higher degradation ratio at 25 and 30℃ was observed and the optimum condition for the bacteria to degrade imazethapyr was pH = 5 and 25℃. Characterizing by physiological and biochemical properties as well as 16S rRNA sequence analysis, the strain is related and shared characteristics of the genus Alcaligenes sp.