1200ITU/mg Bti浓悬浮剂的研制

摘要

The culture medium for highly toxic Bacillus thuringiensis subsp. Israelensis L-10 strain was obtained by orthogonal tests of nitrogen source. The formula with good physicochemical properties was conducive to the post-treatment. In the pilot fermentation in 200 L fermentors, the potency of the fermentation broth was 395 ITU/|xL. After the optimization of post-treatment, the optimal route of 1 200 ITU/mg Bti suspension concentrate was developed. It was prepared by using fermentation broth to the secondary centrifugation and high-powered concentration, then adding additive and grinding with sand mill. Its titer reached 1 245 ITU/mg against mosquito larva.%通过对苏云金芽孢杆菌以色列亚种Bti L-10菌株进行培养基的改良优化得到一种理化性质好、利于后处理的配方.200 L罐发酵效价达395 ITU/μL;通过后处理工艺的优化,得到一种制备1 200 ITU/mgBti浓悬浮剂路线,即发酵液2次离心并高倍浓缩得到菌浆,添加各种助剂经砂磨机研磨,得到Bti浓悬浮剂产品效价达到1 245 ITU/mg.