Identification of Metabolites and Pathway in Liver Microsomes of Phoxim in Crucian Carp by High Performance Liquid Chromatography and Liquid Chromatography Electrospray Ionization Tandem Mass Spectrometry
The liver microsomes were prepared by differential ultracentrifugation for the investigation of in vitro metabolism of phoxim.The metabolites were extracted twice from the reaction solution with ethyl acetate,remove the organic phase to rotary evaporator by near dryness at 40 ℃,then constant volume by 1mL methanol,separated and determined by HPLC,and then identified by HPLC-MS(ESI).Three major metabolites(M1: O,O,O’,O’-tetraethyldithiopyrophosphate,M2: diethylthiophosphate and M3: phoxom) indicated that phoxim underwent desulfur-oxidation and hydrolysis in crucian carp liver microsomes.Therefore,this study deduced the metabolic pathway and metabolic characteristic of phoxim in liver microsomes of crucian carp and laid a solid foundation for further study of its metabolism and metabolic enzymes.