阿维菌素在土壤中的微生物降解研究

Microbial degradation of Abamectin in soil.

运用恒温培养法研究了阿维菌素在土壤中的降解动力学 .结果表明 ,非生物 +微生物降解、非生物降解及微生物降解的半衰期分别为 34 8、2 77 3和 4 9 9d ,说明阿维菌素在土壤中的降解主要由微生物引起 .从试验土壤中分离到 1株高效降解阿维菌素的菌株 ,经 16SrDNA鉴定为嗜麦芽寡养单胞菌(Stenotrophomonasmaltrophilia) .从该降解菌中提取的粗酶液米氏常数 (Km)为 6 78nmol·ml-1,最大降解速率为 81 5nmol·min-1·mg-1.

Incubation test on the degradation dynamics of Abamectin in soil showed that the half-life of its non-biodegradation plus microbial biodegradation,non-biodegradation,and microbial biodegradation was 34.8,277.3 and 49.9 d,respectively,and its degradation in soil was mostly by microbes.A dominant bacterium which could effectively degrade Abamectin was isolated from test soil,and identified as Stenotrophomonas maltrophilia by 16S rDNA.The crude enzyme extracted from the dominant bacteria had a Michaelis-Mentn's constant 6.78 nmol·ml -1 and a maximum rate 81.5 nmol·min -1 ·mg -1 .