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Updated: May 13, 2026

Semi-Targeted Ultra-High-Performance Chromatography Coupled to Mass Spectrometry Analysis of Phenolic Metabolites in Plasma of Elderly Adults
Published on: April 22, 2022
Absorption and isomerization of caffeoylquinic acids from different foods using ileostomist volunteers
T Erk1, M Renouf, G Williamson
1Department of Chemistry, Division of Food Chemistry and Toxicology, University of Kaiserslautern, Erwin-Schroedinger-Str. 52, 67663, Kaiserslautern, Germany.
Background:
Polyphenols are thought to play important roles in human nutrition and health but these health effects are dependent on their bioavailability. This study is one of a series with the aim of determining possible effects of food matrices on caffeoylquinic acid (CQA) bioavailability using ileostomy volunteers.
Methods:
After a CQA-free diet, ileostomists consumed coffee (746 μmol total CQA), and CQAs in excreted ileal fluid were subsequently identified and quantified with HPLC-diode array detection and HPLC-ESI-MS/MS. In our previous studies, other food sources such as cloudy apple juice (CAJ) (358 μmol CQA) and apple smoothie (AS) (335 μmol CQA) were investigated with the same model.
Results:
Interesterification of CQA from both apple matrices was observed during gastrointestinal passage, whereas CQA consumed in coffee was not influenced by interesterification reactions. In total, 74.3, 22.4, and 23.8 % of the CQA from CAJ, AS, and coffee, respectively, were absorbed or degraded.
Conclusion:
Our results show that variations in food matrices and variations in phenolic composition have a major influence on intestinal bioavailability and interesterification of the investigated subclass of polyphenols, the CQAs.
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