Send to

Choose Destination
See comment in PubMed Commons below
Arch Biochem Biophys. 2003 Sep 1;417(1):12-7.

Antioxidative flavonoid quercetin: implication of its intestinal absorption and metabolism.

Author information

Department of Nutrition, School of Medicine, The University of Tokushima, Kuramoto-cho 3, Tokushima 770-8503, Japan.


Quercetin is a typical flavonoid ubiquitously present in fruits and vegetables, and its antioxidant effect is implied to be helpful for human health. The bioavailability of quercetin glycosides should be clarified, because dietary quercetin is mostly present as its glycoside form. Although quercetin glycosides are subject to deglycosidation by enterobacteria for the absorption at large intestine, small intestine acts as an effective absorption site for glucose-bound glycosides (quercertin glucosides). This is because small intestinal cells possess a glucoside-hydrolyzing activity and their glucose transport system is capable of participating in the glucoside absorption. A study using a cultured cell model for intestinal absorption explains that the hydrolysis of the glucosides accelerates their absorption in the small intestine. Small intestine is also recognized as the site for metabolic conversion of quercetin and other flavonoids as it possesses enzymatic activity of glucuronidation and sulfation. Modulation of the intestinal absorption and metabolism may be beneficial for regulating the biological effects of dietary quercetin.

[Indexed for MEDLINE]
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Support Center