毒死蜱降解菌的筛选及其特性的研究

Study on the Screening of Chlorpyrifos-degrading Bacteria and Their Characteristics

[目的]筛选对毒死蜱具有良好降解作用的菌株,为利用微生物进行有机磷农药土壤修复提供理论依据。[方法]采用富集分离法从喷施毒死蜱的土壤中分离出4株对毒死蜱有良好降解作用的菌株,经复筛最终得到1株能够高效降解毒死蜱农药的微生物菌株D12,在充分供氧的条件下,研究菌株降解毒死蜱的降解过程、生长条件及其影响因素,并在纯培养的条件下测定该菌株对毒死蜱的降解效果。[结果]当接种量为菌浓度OD560=0.179,最适pH值为7.0,温度为30℃,毒死蜱浓度为100mg/L时,该菌株D12培养6d后的降解率达到50.4%。该菌生长的最佳毒死蜱浓度为1000mg/L,对毒死蜱的最大耐受浓度为3000mg/L。[结论]试验筛选的菌株D12在基础培养基中对毒死蜱有较强的降解能力。

[ Objective] The study aimed to screen the strain that had good degradation on the chlorpyrifos and provided the theoretical basis for the soil remediation on the organophosphorus pesticide by using microorganism. [ Method] 4 strains that had good degradation on the chlorpyrifos were isolated from the soil which was sprayed with chiorpyrifos by enrichment culture. Through secondary screening, 1 microorganism strain D12 that could effectively degrade chlorpyrifos pesticide was obtained fimially. The degrading process, growth condition and their effecring factors of the strain in degrading chlorpyrifos were studied under the condition of full oxygen supply and the degrading effect of the strain on chlorpyrifos was determined under pure culture. [ Result] When the inoculation amount was strain cencn. OD560 =0. 179, the optimum pH was 7.0, the temperature for growth was 30 ℃ and the chlorpyrifos was 100 mg/L, the degrading rate of the strain reached 50.4%. The optimum chlorpyrifos concn, for the strain growth was 1 000 mg/L and the maximum tolerated cohen, of the strain for chiorpyrifos was 3 000 mg/L. [ Conclusion] The strain D12 screened from the experiment showed stronger the degrading ability on chiorpyrifos in basic medium.