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Updated: May 13, 2026

Analyzing Beneficial Effects of Nutritional Supplements on Intestinal Epithelial Barrier Functions During Experimental Colitis
Published on: January 5, 2017
Bioavailability of dietary (poly)phenols: a study with ileostomists to discriminate between absorption in small and
Gina Borges1, Michael E J Lean, Susan A Roberts
1Plant Products and Human Nutrition Group, School of Medicine, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK.
Abstract:
A feeding study was carried out in which six healthy ileostomists ingested a juice drink containing a diversity of dietary (poly)phenols derived from green tea, apples, grapes and citrus fruit. Ileal fluid and urine collected at intervals over the ensuing 24 h period were then analysed by HPLC-MS. Urinary excretions were compared with results obtained in an earlier study in which the juice drink was ingested by ten healthy control subjects with an intact colon. Some polyphenol components, such as (epi)catechins and (epi)gallocatechin(s), were excreted in urine in similar amounts in ileostomists and subjects with an intact colon, demonstrating that absorption took place principally in the small intestine. In the urine of ileostomists, there were reduced levels of other constituents, including hesperetin-7-O-rutinoside, 5-O-caffeoylquinic acid and dihydrochalcones, indicating their absorption in both the small and large intestine. Ileal fluid analysis revealed that even when absorption occurred in the small intestine, in subjects with a functioning colon a substantial proportion of the ingested components still pass from the small into the large intestine, where they may be either absorbed before or after catabolism by colonic bacteria.
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