Comparative biokinetics and metabolism of pure monomeric, dimeric, and polymeric flavan-3-ols: A randomized cross-over study in humans

authored by: S. Wiese, T. Esatbeyoglu, P. Winterhalter, H.-P. Kruse, S. Winkler, A. Bub, S.E. Kulling
Abstract: Scope: Flavan-3-ols are abundant polyphenols in human nutrition and are associated with beneficial health effects. The aim of this study was to comparatively investigate the metabolic fate of (-)-epicatechin, procyanidin B1, and polymeric procyanidins in a randomized cross-over study in humans. Methods and results: Parent compounds, conjugates, and microbial metabolites were determined in plasma, urine, and faeces by HPLC-MS and GC-MS/MS. Glucuronidated, sulfated, and methylated (-)-epicatechin and 5-(3′,4′-dihydroxyphenyl)-valerolactone were the dominant metabolites in blood and urine. In addition, minor amounts of procyanidin B1 and 4-hydroxy-5-(3′,4′-dihydroxyphenyl)valeric acid and their conjugated metabolites were detected. The formation of 5-(3′,4′-dihydroxyphenyl)-valerolactone and 4-hydroxy-5-(3′,4′-dihydroxyphenyl)valeric acid varied largely between individuals as well as with the degree of polymerization of flavan-3-ols. Monomer units were not detectable in plasma or urine after procyanidin B1 and polymeric procyanidin intake. No correlation was found between the intake of flavan-3-ols and the occurrence of phenolic acids in blood and urine or the phenolic compound profiles in faeces. Conclusion: In addition to conjugated metabolites derived from the absorption of monomeric flavan-3-ols, 5-(3′,4′-dihydroxyphenyl)-valerolactone represents an important in vivo metabolite of (-)-epicatechin and procyanidin B1 produced by the gut microbiota.
Organisation(s): Institute of Food Science and Human Nutrition
Molecular Food Chemistry and Food Development
Type: Article
Journal: Molecular Nutrition and Food Research
Volume: 59
Pages: 610-621
No. of pages: 12
ISSN: 1613-4125
Publication date: 01.04.2015
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Biotechnology, Food Science
Sustainable Development Goals: SDG 3 - Good Health and Well-being
Electronic version(s): https://doi.org/10.1002/mnfr.201400422 (Access: Closed)