锐劲特降解菌株R-2的分离、鉴定及降解特性

Isolation and characterization of a fipronil-degrading strain R-2 and its degrading characteristics

摘要:

从长期受锐劲特污染的农药厂活性污泥中分离到一株锐劲特降解菌株R-2, 根据其生理生化特征和16S rRNA基因序列同源性分析, 将该菌株鉴定为Paracoccus sp.。菌株R-2能以锐劲特为唯一碳源生长, 在含有50 mg/L的锐劲特的基础盐培养基中, 3 d的降解率达到85%。菌株R-2降解锐劲特的最适温度为30 °C, 最适pH值为6.0?7.0, 其降解锐劲特的效率与锐劲特初始浓度呈负相关。添加0.1 mmol/L的Zn2+或Fe3+能够显著促进菌株对锐劲特的降解。灭菌与非灭菌土壤降解试验表明, 菌株R-2均可以在10 d内降解63.4%?71.2%的100 μg/g的锐劲特。

Abstract:

A bacterial strain R-2, capable of degrading fipronil, was isolated from a long-term fipronil-polluted activated sludge in a fipronil manufacture factory. Strain R-2 was preliminarily identified as Paracoccus sp. based on its physiological and biochemical properties, as well as the 16S rRNA gene sequence analysis. Strain R-2 could utilize fipronil as the sole carbon source for growth, and degrade 85% of 50 mg/L fipronil within 3 d in mineral salts medium. The optimal pH value and temperature for fipronil degradation by strain R-2 were 6.0?7.0 and 30 °C, respectively. The degrading rate showed a negative correlation with the initial concentration of fipronil. The addition of 0.1 mmol/L Zn2+ or Fe3+ to the culture medium could significantly increase the degradation of fipronil. In both sterile and non-sterile soils, strain could remove 63.4%?71.2% of 100 μg/g fipronil within 10 d.