Daidzein Intake Is Associated with Equol Producing Status through an Increase in the Intestinal Bacteria Responsible for Equol Production

Abstract

Equol is a metabolite of isoflavone daidzein and has an affinity to estrogen receptors. Although equol is produced by intestinal bacteria, the association between the status of equol production and the gut microbiota has not been fully investigated. The aim of this study was to compare the intestinal bacteria responsible for equol production in gut microbiota between equol producer and non-producer subjects regarding the intake of daidzein. A total of 1044 adult subjects who participated in a health survey in Hirosaki city were examined. The concentration of equol in urine was measured by high-performance liquid chromatography. The relative abundances of 8 bacterial species responsible for equol production in the gut microbiota was assessed using 16S rRNA amplification. There were 458 subjects identified as equol producers. The proportion of equol production status and the intake of daidzein increased with age. Daily intake of daidzein was larger in equol-producer. The intestinal bacteria, which convert daidzein to equol were present in both equol producers and non-producers. However, the relative abundance and the prevalence of Asaccharobacter celatus and Slackia isoflavoniconvertens were significantly higher in equol producers than those in equol non-producers. The intestinal bacteria that convert daidzein to equol are present in not only the equol producers but also in the non-producers. The daidzein intake is associated with the equol production status through an increase of A. celatus and S. isoflavoniconvertens in the gut microbiota.

Dietary intake of isoflavones is associated with a lower prevalence of subclinical cardiovascular disease in postmenopausal women: cross‐sectional study

“…Indeed, equol‐producing ability varies greatly among individuals and higher dietary isoflavone consumption was associated with a lower IMT in equol producers but not in equol non‐producers in a study involving 572 healthy Chinese adults . Interestingly, recent reports suggest that the equol production status might be associated with intake of dietary isoflavones and a healthy diet pattern by increasing gut microbiome diversity . Although our participants with higher isoflavone dietary intake could present a better gut microbiome profile, the equol‐producing ability could not be assessed in the present study because of the lack of specific biological (urine) samples.…”

Disease severity and proton pump inhibitor use impact strongest on faecal microbiome composition in liver cirrhosis

“…However, none of these have been previously described to be associated with age related changes in microbiome composition. Collinsella aerofaciens has been associated with diet and intestinal inflammatory diseases, Slackia with equol production, whereas Alistipes onderdonkii has not been associated with any human condition yet …”

“…Collinsella aerofaciens has been associated with diet and intestinal inflammatory diseases, [58][59][60] Slackia with equol production, 61 whereas Alistipes onderdonkii has not been associated with any human condition yet. 62 Nutritional status is an important prognostic factor in liver cirrhosis.…”

Effects of Phytoestrogens on the Developing Brain, Gut Microbiota, and Risk for Neurobehavioral Disorders

“…Within Asian populations, increased consumption of soy is associated with increased number of equol-generating bacteria within the intestine (12). A similar study found that ingestion of daidzein positively correlated with greater abundance of Asaccharobacter celatus and Slackia isoflavoniconvertens, two equol producing bacteria (13). Other rodent and human studies suggest that genistein (GEN) or soy based foods impacts gut microorganisms (14)(15)(16)(17)(18)(19)(20)(21)(22).…”