title: Long-term kinetics of daidzein and its main metabolites in human equol-producers after soymilk intake: identification of equol-conjugates by UPLC-orbitrap-MS and influence of the number of transforming bacteria on plasma kinetics.
abstract: The main aim of the study was to establish in vivo a correlation between equol (EQU) production and a number of intestinal bacteria able to perform the transformation. Thus, healthy female volunteers were selected for their ability to convert slowly (n = 6, 105-109cells/g wet feces) or quickly (n = 6, 1010-1012cells/g wet feces) daidzein (DAI) in EQU. After oral administration of 100 mg DAI in soymilk, plasma (0-99 h) and urine (0-96 h) samples were collected. DAI and its metabolites were determined by LC-MS/MS and EQU -conjugates by UPLC-High Resolution-MS. Only for EQU a direct correlation was found between the number of transforming microorganisms and parameters such as tmaxand t1/2(p = 0.027). Peak serum concentration time, Cmax, AUC0-72 hand t1/2for total EQU (n = 12) were 36 ± 10 h, 89 ± 78 nM, 2.4 ± 1.7 (μmol × h/L) and 15.6 ± 3.3 h, respectively. In plasma and urine EQU was found mainly as 7-O-glucuronide.
authors.affiliation: a Department of Food, Environmental and Nutritional Sciences, Division of Human Nutrition , Università degli Studi di Milano , Milano , Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Gardana
authors.affiliation: a Department of Food, Environmental and Nutritional Sciences, Division of Human Nutrition , Università degli Studi di Milano , Milano , Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Simonetti
mesh_terms: D019540:Area Under Curve; D001419:Bacteria / Q000145:classification* / Q000378:metabolism; D002853:Chromatography, Liquid / Q000379:methods*; D060754:Equol / Q000737:chemistry / Q000378:metabolism*; D006207:Half-Life; D006801:Humans; D007529:Isoflavones / Q000737:chemistry / Q000378:metabolism* / Q000493:pharmacokinetics*; D013058:Mass Spectrometry / Q000379:methods*; D015394:Molecular Structure; D041942:Soy Milk / Q000378:metabolism*
chemical_list: D007529:Isoflavones; D060754:Equol; C004742:daidzein
keywords: Daidzein; equol; human; mass spectrometry; metabolism; pharmacokinetics