Systematic analysis of the polyphenol metabolome using the Phenol-Explorer database

Area of Science:

• Metabolomics
• Nutritional Science
• Pharmacokinetics

Background:

• Dietary polyphenols are plant-derived compounds with potential health benefits.
• Their in vivo effects depend on absorption, metabolism, and bioavailability.
• The full spectrum of polyphenol metabolites in humans and animals is not well-characterized.

Purpose of the Study:

• To characterize and visualize the polyphenol metabolome using existing data.
• To analyze qualitative and quantitative data on polyphenol metabolites from human and animal studies.
• To understand the biotransformations of dietary polyphenols in vivo.

Main Methods:

• Systematic analysis of data from the Phenol-Explorer web database.
• Inclusion of 383 polyphenol metabolites from 221 publications and 424 intervention studies.
• Identification of metabolites with and without enzymatic hydrolysis of biofluids.

Main Results:

• 301 metabolites identified without hydrolysis, including various conjugates and aglycones.
• Approximately one-third of metabolites were direct food constituents.
• Gut microbiota significantly contribute to metabolite formation, particularly from hydroxycinnamates, flavanols, and flavonols.
• Median C(max) in humans was 0.09 microM (food) and 0.32 microM (supplements).
• Median T(max) in humans was 2.18 hours.

Conclusions:

• The polyphenol metabolome is highly complex.
• Biotransformations, especially by gut microbiota, are crucial for polyphenol activity.
• Understanding these metabolic pathways is essential for elucidating the role of dietary polyphenols in health and disease.