Bioscience and Microflora
Online ISSN : 1349-8355
Print ISSN : 1342-1441
ISSN-L : 1342-1441
30 巻 , 3 号
Full Paper
  • Motoi Tamura, Sachiko Hori, Hiroyuki Nakagawa
    原稿種別: Full Paper
    2011 年 30 巻 3 号 p. 65-71
    発行日: 2011年
    公開日: 2011/08/15
    ジャーナル フリー
    Much attention has been focused on the biological effects of equol, a metabolite of daidzein produced by intestinal microbiota. However, little is known about the role of isoflavone metabolizing bacteria in the intestinal microbiota. Recently, we isolated a dihydrodaidzein (DHD)-producing Clostridium-like bacterium, strain TM-40, from human feces. We investigated the effects of strain TM-40 on in vitro daidzein metabolism by human fecal microbiota from a male equol producer and two male equol non-producers. In the fecal suspension from the male equol non-producer and DHD producer, DHD was detected in the in vitro fecal incubation of daidzein after addition of TM-40. The DHD concentration increased as the concentration of strain TM-40 increased. In the fecal suspension from the equol producer, the fecal equol production was increased by the addition of strain TM-40. The occupation ratios of Bifidobacterium and Lactobacillales were higher in the equol non-producers than in the equol producer. Adding isoflavone-metabolizing bacteria to the fecal microbiota should facilitate the estimation of the metabolism of isoflavonoids by fecal microbiota. Studies on the interactions among equol-producing microbiota and DHD-producing bacteria might lead to clarification of some of the mechanisms regulating the production of equol by fecal microbiota.