title: Rapid and convenient detection of urinary equol by thin-layer chromatography.
abstract: Equol, a metabolite of daidzein for some intestinal microflora, is known to retain highly estrogenic activity and is of wide interest in relation to human health. However, not all humans can produce equol. In this study, detection of urinary equol using thin-layer chromatography (TLC) was performed to distinguish between equol producers and non-producers. After 36 h of soy food intake, urine, collected from 7 volunteers, was hydrolyzed, purified by reverse phase silica gel column and applied to normal phase TLC. Consequently, equol was clearly separated from the urine samples and discriminated the equol producers in this system. The detection limit of equol was at least 20 ng.
authors.affiliation: Research Institute for Bioengineering, Gifu Prefectural Government, 3481-2 Kamihachiya, Hachiya-cho, Minokamo, Gifu 505-0004, Japan. yokoyama@bio.rd.pref.gifu.jp
authors.forename: Shin-Ichiro
authors.initials: S
authors.lastname: Yokoyama
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Kuzuguchi
mesh_terms: D015415:Biomarkers / Q000652:urine; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D002855:Chromatography, Thin Layer / Q000379:methods; D060754:Equol; D006801:Humans; D007529:Isoflavones / Q000302:isolation & purification / Q000652:urine*; D012680:Sensitivity and Specificity; D045730:Soy Foods; D030262:Soybean Proteins / Q000378:metabolism
chemical_list: C007610:4',7-dihydroxy-3,4-dihydroisoflavone; D015415:Biomarkers; D007529:Isoflavones; D030262:Soybean Proteins; D060754:Equol