title: Conversion of dieldrin to aldrin by intestinal bacteria in rats.
abstract: The present study provides the evidence that dieldrin is reductively metabolized to aldrin by intestinal bacteria in rats. When dieldrin was incubated with the cecal contents of rats, aldrin, a reduced metabolite of the epoxide, was isolated from the incubation mixture. The metabolite was identified unequivocally by UV and mass spectral comparison with an authentic sample, and on the basis of its TLC and HPLC behavior. The cecal contents of rats exhibited epoxide reductase activity toward dieldrin under anaerobic conditions. However, only marginal activity was observed under aerobic conditions. Four pure strains of intestinal bacteria exhibited epoxide reductase activities to varying degrees under anaerobic conditions. The highest activity was observed in Clostridium sporogenes. Cell-free extracts of the intestinal bacteria in rat cecal contents showed reductase activity when supplemented with both NAD(P)H and FMN under anaerobic conditions.
authors.affiliation: Institute of Pharmaceutical Science, Hiroshima University School of Medicine, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Kitamura
authors.forename: M
authors.initials: M
authors.lastname: Mita
authors.forename: Y
authors.initials: Y
authors.lastname: Shimizu
authors.forename: K
authors.initials: K
authors.lastname: Sugihara
authors.forename: S
authors.initials: S
authors.lastname: Ohta
mesh_terms: D000452:Aldrin / Q000378:metabolism*; D000818:Animals; D003013:Clostridium / Q000378:metabolism; D004026:Dieldrin / Q000493:pharmacokinetics*; D013293:Enterococcus faecalis / Q000378:metabolism; D004926:Escherichia coli / Q000378:metabolism; D007422:Intestines / Q000382:microbiology*; D007778:Lactobacillus / Q000378:metabolism; D008297:Male; D051381:Rats; D017208:Rats, Wistar
chemical_list: D004026:Dieldrin; D000452:Aldrin