毒死蜱降解菌的驯化筛选及高活性毒死蜱降解菌群的构建

Domestication and Screening of Chlorpyrifos-degrading Bacteria and Construction of Composited Flora with High Chlorpyrifos-degrading Capacity

[目的]通过对3种活性污泥的长期驯化、微生物多样性分析及优势菌筛选与复配,构建一种对毒死蜱具有高降解活性的菌群。[方法]以农药公司的3种不同废水处理工序的污泥为材料,利用毒死蜱长期胁迫驯化以获得高效降解毒死蜱的活性污泥;随后,在驯化后的3种活性污泥中筛选优势菌株,并以筛选的菌株构建复合菌群用于毒死蜱的降解。[结果]以毒死蜱为碳源,在驯化后的活性污泥中筛选到3株具有毒死蜱降解活性的菌株(Paracoccus MLCa-1、Klebsiella MLCp-2、Serratia MLCs-1),并对3种菌株进行复配,构建了复合菌群MLCF7。复合菌群MLCF7对100 mg/L毒死蜱降解率达82.84%。[结论]复合菌群对毒死蜱具有高降解活性,表明其在农药污染生物修复中具有应用潜力。

[Objective]Based on three activated sludges,through long-term domestication,analysis of microbial diversity,and dominant bacteria screening and composition to construct a composited flora with high chlorpyrifos-degrading capacity.[Method]Using sludge from 3 different wastewater treatment processes of pesticide companies as materials,the chlorpyrifos long-term stress domestication was used to obtain activated sludge that efficiently degrades chlorpyrifos;subsequently,the dominant strains were screened from the three domesticated activated sludges,and the screened strains were used to construct a complex flora for the degradation of chlorpyrifos.[Result]Using chlorpyrifos as a carbon source,three dominant bacterial strains(Paracoccus MLCa-1,Klebsiella MLCp-2,and Serratia MLCs-1)were screened from these domesticated activated sludges when chlorpyrifos as the carbon source.A chlorpyrifos-degrading flora was constructed by composition of these three dominant bacterial strains.The degradation capacity of the composited flora MLCF7 was reached 82.84%towards 100 mg/L chlorpyrifos.[Conclusion]The easily constructed composited flora MLCF7 has high degradation activities to chlorpyrifos,indicating it has the application potential for bioremediation of pesticide contamination.