欢迎访问《环境科学学报》编辑部网站！

快速检索			高级检索

污染控制技术及原理

Isolation, identification and degradation-efficiency measurement of chlorpyrifos-degradaing bacteria

摘要：取毒死蜱废水处理系统出口处的污泥进行驯化培养,分离出能降解毒死蜱的3株高效降解菌株B、D₁和D₃,对降解效果最好的D3菌株经中科院微生物研究所鉴定为玫瑰红红球菌(Rhodococcus rhodochrous);3株菌株的生长情况及对毒死蜱的降解动力学研究表明,B菌株在第3天繁殖增量达到最大,D₁、D₃菌株在第4天繁殖增量达到最大,B、D₁和D₃菌株的最适宜生长温度都是在30℃;采用10mg·L^-1毒死蜱作为唯一碳源时,B、D₁和D₃菌株对毒死蜱的降解速率分别为0.0543、0.0479和0.0620h^-1;对于浓度为10mg·L^-1的毒死蜱,D₃菌投入的初始菌量OD₂₂₃为0.4是最适宜的;D₃菌对不同初始浓度的毒死蜱降解表明,初始浓度增大,降解速率降低,半衰期延长.

Abstract：Three bacterial strains that had a capability to utilize chlorpyrifos as the sole carbon and energy sources were isolated from the sludge. Based on the morphology and physio-biochemical properties, the strain D₃ which had the best degradation capability to chlorpyrifos was identified as Rhodococcus rhodochrous by Institute of Microbiology Chinese Academy of Sciences. The biomass got to the maximum when strain B was cultivated for 3 d, however strains D₃ and D₁ need 4 d. The optimal cultivating temperature of all the strains was 30 ℃. In aqueous solution of chlorpyrifos at the concentration of 10 mg·L^-1, the degradation rate constants of strains B, D₁ and D₃ utilizing chlorpyrifos as the sole carbon source were 0.0479, 0.0543 and 0.0620 h^-1, respectively. It was optimal that the OD₂₂₃ of strain D₃ solution attained 0.4 for the degradation of chlorpyrifos at the concentration of 10 mg·L^-1. The results also showed that the degradation efficiency of the strain D₃ to chlorpyrifos decreased with initial concentration of chlorpyrifos increasing.