title: Phyto-oestrogen content of berries, and plasma concentrations and urinary excretion of enterolactone after a single strawberry-meal in human subjects.
abstract: Quantitative data on phyto-oestrogen, particularly lignan, content in edible plants are insufficient. We, therefore, measured isoflavonoids and lignans in nine edible berries using an isotope dilution gas chromatography-mass spectrometry method for foods and found substantial concentrations of the lignan secoisolariciresinol (1.39-37.18 mg/kg DM), low amounts of matairesinol (0-0.78 mg/kg DM) and no isoflavones. To determine pharmacokinetics and urinary excretion pattern of the mammalian lignan enterolactone derived from plant lignans, a study with human subjects was conducted. Five healthy women and two men consumed, after a 72 h period of a phyto-oestrogen-free regimen, a single strawberry-meal containing known amounts of plant lignans. Basal and post-meal blood and urine samples were collected at short intervals. The samples were analysed using time-resolved fluoroimmunoassay of enterolactone. The meal increased plasma concentration of enterolactone after 8-24 h and in urine in the 13-24 h and 25-36 h urine collections. High individual variability of the metabolic response was observed. Enterolactone excreted in the urine collected throughout the 48 h post-meal yielded on average 114% of the plant lignans consumed. It is concluded that berries containing relatively high concentrations of plant lignans contribute to plasma and urinary levels of mammalian enterolactone in human subjects.
authors.affiliation: Folkhälsan Institute for Preventive Medicine, Nutrition and Cancer, University of Helsinki, Finland.
authors.forename: W M
authors.initials: WM
authors.lastname: Mazur
authors.forename: M
authors.initials: M
authors.lastname: Uehara
authors.forename: K
authors.initials: K
authors.lastname: Wähälä
authors.forename: H
authors.initials: H
authors.lastname: Adlercreutz
mesh_terms: D000328:Adult; D005260:Female; D015200:Fluoroimmunoassay; D005638:Fruit / Q000737:chemistry*; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D007529:Isoflavones / Q000032:analysis*; D007783:Lactones / Q000097:blood / Q000493:pharmacokinetics* / Q000652:urine; D017705:Lignans / Q000032:analysis* / Q000493:pharmacokinetics; D008297:Male; D008875:Middle Aged
chemical_list: D007529:Isoflavones; D007783:Lactones; D017705:Lignans