【摘要】 利用生物测定，ＳＤＳ－ＰＡＧＥ方法对苏云金杆菌ＧＣ－９１发酵液的上清液进行了研究。研究表明，上清液中含有增效物质，离心丢弃上清液是导致毒力收率大幅度下降的根本原因。上清液对粉剂增效明显，本实验中最高增效倍数为２３．５倍，且上清液对不同菌种粉剂增效力不同，对ＧＣ－９１菌粉增效极为显著，对ＨＤ－１菌粉增效较为缓慢。上清液中含有的增效物质是一种热稳定物质，能耐１５分钟沸水浴，在ｐＨ２～１０范围内稳定，证明不是β－毒素更多还原

【Abstract】 Testing on the culture supernatant of Bacillus thuringiensis GC 91 by bioassay and SDS PAGE, found that it has some synergistic action to Bt dust. The same supernatant may have different synergistic action on different Bt strains. For instance, the supernatant of GC 91 reacts quickly to GC 91 dust but slowly to HD 1 dust. Further research showed that this “synergiser” is thermostable and also stable at pH2-pH10. It is not β exotoxin, however.更多还原