Isolation and Identification of the Insecticidal Ingredients from the Fermentation Broth of Streptomyces qinlingnensis

A new actinomycete was isolated from the soil of Qinling mountain area and named Streptomyces qinlingnensis sp.nov.Previous research results showed that the fermentation broth exhibited high fungicidal activity against several species of fungus and bacteria,and moderate insecticidal activity against Plutella xylostella.Three insecticidal compounds were isolated from fermentation broth by macro porous,silica gel column chromatography and pre-HPLC.They were identified as avermectin B1a, B2a and A1a based on the data of HR-MS and NMR spectrum. The results indicated that Streptomyces qinlingnensis,which was not cognate with Streptomyces avermectinius, also could produce avermectins.