The Study Of The Biotransformation Of Paichongding And Avermectins

In this paper，the biotransformation of Paichongding, which is a kindof neonicotinoids and Avermectins, a group of fermentation productsfrom Streptomyces avermitilis was studied.A microbial strain had ability to convert Paichongding by screeningof1131strains. After separation and purification throughchromatographic methods, the product was identified by ESI-MS, NMR.The spectra date showed that the molecular fomula of the product isC14H17N4O3Cl,with a molecular weight of324, as the same as a knowcompound of1-[(6-chloropyridin-3-yl)methyl]-7-methyl-8-nitro-1,2,3,5,6,7-hexahydroimidazo[1,2-α]pyridin-5-ol. The conversion rate is94.8%at0.2mg/ml of theconcentration of Paichongding, pH7and28℃for48hours. Theinsecticidal activity against the larvae of Culex Pipiens betweenPaichongding and the product was envaluated, the LC50and its95%confidence limits of Paichongding were8.295(7.490-9.324)mg/l and theproduct were5.739(5.303-6.195)mg/l. It was found that the insecticidalactivity of the product was higher.The biotransformation of Avermectins by Catharanthus roseussuspension cell was studied. Analysis by TLC, HPLC, Two products havegood insecticidal activity against the larvae of Culex pipiens. Themorality of the two product is63.7%and73.8%.