Microbial and dietary factors are associated with the equol producer phenotype in healthy postmenopausal women

Bolca, Selin, Possemiers, Sam, Herregat, Annelies, Huybrechts, Inge, Heyerick, Arne, De Vriese, Stephanie, Verbruggen, Marian, Depypere, Herman, De Keukeleire, Denis, Bracke, Marc, De Henauw, Stefaan, Verstraete, Willy and Wiele, Tom Van de (2007) Microbial and dietary factors are associated with the equol producer phenotype in healthy postmenopausal women. The Journal of Nutrition, 137 10: 2242-2246.

Author Bolca, Selin
Possemiers, Sam
Herregat, Annelies
Huybrechts, Inge
Heyerick, Arne
De Vriese, Stephanie
Verbruggen, Marian
Depypere, Herman
De Keukeleire, Denis
Bracke, Marc
De Henauw, Stefaan
Verstraete, Willy
Wiele, Tom Van de
Title Microbial and dietary factors are associated with the equol producer phenotype in healthy postmenopausal women
Journal name The Journal of Nutrition   Check publisher's open access policy
ISSN 0022-3166
Publication date 2007-10
Sub-type Article (original research)
Volume 137
Issue 10
Start page 2242
End page 2246
Total pages 5
Place of publication Bethesda, MD, United States
Publisher American Society for Nutrition
Language eng
Subject 110801 Medical Bacteriology
Abstract Equol, a microbial metabolite of daidzein, has been hypothesized as a clue to the effectiveness of soy and its isoflavones but is excreted by only 33% of Caucasians. Microbial and dietary factors associated with the ability to harbor equol-producing bacteria were studied in a randomized dietary intervention trial with 100 healthy postmenopausal women. After a 4-d baseline period, subjects delivered first-void urine, fecal, and breath samples. During the 5-d treatment period, 3 portions of either soymilk or soy germ containing 28.51 and 37.99 mg isoflavone aglycone equivalents/portion, respectively, were administered daily, and on the last day, 24-h urine samples were collected. The urinary recoveries of genistein and daidzein from soymilk were significantly higher than those from soy germ tablets. Because the proportion of equol:(daidzein + metabolites) in the urine did not differ between the treatment groups, subjects were pooled and classified into poor, moderate, and strong equol producers based on this criterion. The strong equol producer phenotype correlated negatively [in vivo, r = –0.478 (–0.256 to –0.893), P = 0.021; in vitro, r = –0.576 (–0.350 to –0.949), P = 0.030] with Clostridium coccoides-Eubacterium rectale counts and positively [in vivo, r = 1.158 (0.971–1.380), P = 0.048; in vitro, r = 1.156 (1.007–1.327), P = 0.039] with the abundance of sulfate-reducing bacteria. Furthermore, persons with a higher PUFA [in vivo, r = 2.150 (1.058–4.371), P = 0.034; in vitro, r = 2.131 (1.144–3.967), P = 0.017] and alcohol [in vivo, r = 1.166 (0.721–1.887), P = 0.050; in vitro, r = 1.850 (1.215–2.817), P = 0.004] intake were more likely to be strong equol producers. Finally, we validated the daidzein metabolism by fecal cultures as screening assay to identify equol producers without dietary intervention.
Keyword Equol
Q-Index Code C1
Q-Index Status Confirmed Code

Document type: Journal Article
Sub-type: Article (original research)
Collections: Excellence in Research Australia (ERA) - Collection
ERA 2012 Admin Only
Advanced Water Management Centre Publications
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 65 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 0 times in Scopus Article
Google Scholar Search Google Scholar
Created: Fri, 13 Feb 2009, 15:43:32 EST by Gina Velli on behalf of Library Corporate Services