Quantification of isoflavones and lignans in urine using gas chromatography/mass spectrometry.

TitleQuantification of isoflavones and lignans in urine using gas chromatography/mass spectrometry.
Publication TypeJournal Article
Year of Publication2003
AuthorsGrace, PB, Taylor, JI, Botting, NP, Fryatt, T, Oldfield, MF, Bingham, SA
JournalAnal Biochem
Volume315
Issue1
Pagination114-21
Date Published2003 Apr 01
ISSN0003-2697
Keywords4-Butyrolactone, Equol, Female, Gas Chromatography-Mass Spectrometry, Genistein, Humans, Isoflavones, Lignans, Molecular Structure, Phytoestrogens, Plant Preparations, Reproducibility of Results, Sensitivity and Specificity
Abstract

Phytoestrogens (isoflavones and lignans) are of increasing interest due to their potential to prevent certain types of complex diseases. However, epidemiological evidence is needed on the levels of phytoestrogens and their metabolites in foods and biological fluids in relation to risk of these diseases. We report an assay for phytoestrogens which is sensitive, accurate, and uses low volumes of sample. Suitable for epidemiological studies, the assay consists of a simple sample preparation procedure and has been developed for the analysis of five isoflavones (daidzein, O-desmethylangolensin, equol, genistein, and glycitein) and two lignans (enterodiol and enterolactone), which requires only 200 microl of urine and utilizes one solid-phase extraction stage for sample preparation prior to derivatization for GC/MS analysis. Limits of detection were in the region 1.2 ng/ml (enterodiol) to 5.3ng/ml (enterolactone) and the method performed well in the UK Government's Food Standards Agency-sponsored quality assurance scheme for phytoestrogens. For the first time, average levels of all the above phytoestrogens were measured in samples of urine collected from a free living population sample of women. Results show a large range in both the amount and the type of phytoestrogens excreted.

DOI10.1016/s0003-2697(02)00707-8
Alternate JournalAnal. Biochem.
Citation Key10.1016/s0003-2697(02)00707-8
PubMed ID12672419