异丙隆降解菌Y57的分离鉴定及其降解特性

从农药厂的活性污泥中分离出1株能高效降解异丙隆的细菌Y57,通过生理生化鉴定和16SrDNA同源性序列分析,鉴定为鞘氨醇单胞菌属(Sphingomonassp.).接种量为1%的Y57可以在48h之内将30mg/L的异丙隆完全降解,降解率达到99%以上,降解最适pH值为7.0,降解效率与接种量呈正相关,在通气良好状况下降解速率较高.1mmol/L的Li⁺、Ca²⁺、Mg²⁺可以提高Y57降解异丙隆速率;1mmol/L的Ni²⁺、Zn²⁺对降解有明显的抑制作用;1000mg/L的酵母粉、葡萄糖、牛肉膏或蛋白胨对降解具有抑制作用.降解谱实验表明,Y57还可以降解绿麦隆、敌草隆、敌稗等除草剂.

Isolation identification of isoproturon degradation bacterium Y57 and its degradation characteristic

A bacterium (Y57) able to degrade efficiently the isoproturon (IPU) was isolated from the active sludge of herbicide factory. Through biochemical-physiological identification and sequence analysis of the 16S rDNA, Y57 was identified as Sphingomonas sp.. The Y57 of inoculation quantity of 1% could degrade completely 30mg/L isoproturon (IPU) in 48h. The most adaptable pH value for IPU degradation by Y57 was 7.0. The degradation rate was related positively to inoculation quantity. The IPU degradation rate of good ventilation state was higher than that at relatively poor ventilation state. The Li+, Ca2+, Mg2+ of 1mmol/L could enhance the IPU degradation rate; but Ni2+, Zn2+ of 1mmol/L could inhibit obviously IPU degradation. Addition of 1000mg/L yeast extract, glucose, beef extract or peptone could inhibit IPU degradation. Y57 could also degrade chlorotoluron, diuron and propail.