Isolation of an anaerobic intestinal bacterium capable of cleaving the C-ring of the isoflavonoid daidzein.
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.
Hur
Hor-Gil
HG
Department of Environmental Science and Engineering, Kwangju Institute of Science and Technology, Korea.
Beger
Richard D
RD
Heinze
Thomas M
TM
Lay
Jackson O
JO
Freeman
James P
JP
Dore
Joel
J
Rafii
Fatemeh
F
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
D007529:Isoflavones; D012336:RNA, Ribosomal, 16S; C004742:daidzein; D002244:Carbon