三唑酮降解菌SM3的降解特性及其应用研究

Study on the degradation characteristics and application of triadimefon-degrading strain SM3

以课题组前期筛选到的1株三唑酮高效降解菌SM3为研究对象,对其降解特性、酶学性质及应用潜力进行了初步研究。结果表明:在纯培养条件下,温度30℃、pH 7.0、接菌量5%、盐浓度10 g·L^(-1)及葡萄糖含量1%为高效降解菌株SM3最适培养条件;通过对降解酶定位发现,降解三唑酮关键酶为胞内酶,且酶促降解最适pH为7.0,最适温度为30℃;室内模拟三唑酮污染土壤分别设置了0.4、2和5 mg·kg^(-1)3个浓度,同时添加菌剂,于1、5、10、15、20和25 d后取样测定土壤中的三唑酮含量。25 d后,3个浓度污染土壤中三唑酮降解率分别达到99.7%,79.1%和58.1%,降解过程符合一级动力学方程。结果可为三唑类杀菌剂三唑酮的生物降解和环境治理提供优良的菌株资源。

In this paper,a triadimefon-degrading strain SM3,which was screened by the research group in the early stage,was taken as the research object,and its degradation characteristics,enzymatic properties and application potential were preliminarily studied.The results showed that:under pure culture conditions,the temperature of 30℃,pH 7.0,inoculum volume of 5%,salt concentration of 10 g·L^(-1) and glucose content of 1%were the optimal culture conditions for the efficient degrading strain SM3.The key enzymes of triadimefon are intracellular enzymes,and the optimum pH for enzymatic degradation is 7.0 and the optimum temperature is 30℃;indoor simulated triadimefon-contaminated soils were set at 0.4,2 and and 5 mg·kg^(-1),respectively.After 1,5,10,15,20 and 25 days,samples were taken to determine the content of triadimefon in the soil.After 25 days,the degradation rates of triadimefon in the contaminated soil with three concentrations reached 99.7%,79.1% and 58.1%,respectively,and the degradation process conformed to the first-order kinetic equation.This study provides an excellent strain resource for the biodegradation and environmental management of triazole fungicides triadimefon.