title: Isolation of an anaerobic intestinal bacterium capable of cleaving the C-ring of the isoflavonoid daidzein.
abstract: Colonic bacteria were screened for bacteria involved in the conversion of phytoestrogens. A gram-positive anaerobic bacterium, strain HGH 136, capable of conversion of the isoflavonoid daidzein, was isolated and identified as a Clostridium sp. The bacterium cleaved the C-ring of daidzein to produce O-demethylangolensin ( O-Dma). This compound was identified by comparison of the HPLC retention time and UV spectrum of the metabolite with chemically synthesized O-Dma. The identity of the metabolite was confirmed by liquid chromatography-mass spectrometry and NMR using synthetic O-Dma as a standard. The bacterium incubated with synthetic dihydrodaidzein also produced O-Dma. After 3 days of incubation, 28% of added daidzein and 12% of added dihydrodaidzein were converted to O-Dma. This is the first study in which an anaerobic bacterium involved in the ring cleavage of daidzein to produce O-Dma has been identified.
authors.affiliation: Department of Environmental Science and Engineering, Kwangju Institute of Science and Technology, Korea.
authors.forename: Hor-Gil
authors.initials: HG
authors.lastname: Hur
authors.forename: Richard D
authors.initials: RD
authors.lastname: Beger
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Heinze
authors.forename: Jackson O
authors.initials: JO
authors.lastname: Lay
authors.forename: James P
authors.initials: JP
authors.lastname: Freeman
authors.forename: Joel
authors.initials: J
authors.lastname: Dore
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Rafii
mesh_terms: D001421:Bacteria, Anaerobic / Q000302:isolation & purification* / Q000378:metabolism; D002244:Carbon / Q000737:chemistry / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D007422:Intestines / Q000382:microbiology*; D007529:Isoflavones / Q000737:chemistry / Q000378:metabolism*; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000032:analysis
chemical_list: D007529:Isoflavones; D012336:RNA, Ribosomal, 16S; C004742:daidzein; D002244:Carbon