硝磺草酮降解菌的分离鉴定及其降解特性

Isolation,identification and characterization of a mesotrione-degrading bacterial strain

采用富集培养法,从活性污泥中分离到硝磺草酮降解菌HZ-2菌株,通过形态、生理生化特征及16SrDNA序列分析,初步鉴定其为短小芽孢杆菌Bacillus pumilus。在通气、pH 7.0、温度30℃、1%接种量、摇速180r/min、50 mL LB培养基条件下共培养5 d,该菌株对200 mg/L硝磺草酮的降解率达到100%。试验结果表明,分离到的硝磺草酮降解菌HZ-2菌株能高度耐受并快速降解硝磺草酮。

A bacterial strain HZ-2 was newly isolated by enrichment culture from the activated sludge in a sewage treatment plant. Based on the morphology, the physiological and biochemical charac- teristics, and 16S rDNA sequence analysis,the strain HZ-2 was identified as Bacillus pumilus HZ-2. The strain HZ-2 could not only completely degrade mesotrione 200 mg/L in 5 d, under the conditions of 1% inoculum, 30 ℃, pH 7.0 and 180 r/min, but also could tolerate and efficiently degrade mesotrione of high concentrations up to 400 mg/L. All these results indicate the strain HZ-2 is deserved to be further developed as a candidate mesotrione-degrading microbe.