DLL-1菌对甲基对硫磷农药的降解作用及其降解机理

Biodegradation of Parathion-methyl by Pseudomonas sp.(DLL-1)and Its Mechanism

摘要: 研究了假单胞菌 (DLL - 1)在水溶液介质中降解甲基对硫磷的性能与影响因素及其降解机理。结果表明 ,当菌体浓度为 10 ⁵个·ml^-1时 ,即发生快速的降解作用 ,3h时 ,降解率达 88.5 %。在pH为 5 .0、7.0和 9.0条件下 ,DLL - 1菌均产生对甲基对硫磷农药的高效降解作用。采用气相色谱 -质谱联用技术与离子色谱法 ,测定了DLL - 1菌 -甲基对硫磷作用过程产生的中间产物和最终产物 ,表明对硝基苯酚为主要中间产物 ,且DLL - 1菌能将其进一步降解为NO₂ ^-和NO₃^- 。

Abstract: Biodegradation of parathion methyl by Pseudomonas sp.(DLL-1)and its influencing factors in solution were studied in the laboratory.Results showed that when the population of DLL-1 bacteria was 10 ⁵ml ^-1 in the solution,high rated biodegradation occurred.It reached 88.5% in 3 h.But the concentration of parathion methyl did not change much in the contrast test.The half time of degradation of parathion methyl was 2.84,0.685 and 1.43 h in the solutions with pH at 5.0, 7.0 and 9.0,respectively.Mechanism of the degradation of parathion methyl by DLL-1 bacteria was also studied.With the aid of GC-MS,IC and Ion Chromatography,intermediate products and final products of the degradation were determined. p Nitro phenol was the main intermediate product and could be further degraded into NO ₂^-and NO ₃ ^- .