AGFD 4 |
| Anthocyanins (ACNs) are unique among the flavonoids in that they are absorbed as the intact glycoside. Berries are rich sources of anthocyanins; differences among the berries in aglycone as well as in sugar moieties provide opportunities to study factors which influence absorption/metabolism. The relative proportions of different metabolites depended upon concentrations, amounts consumed and type of glycosides of ACNs. Cyanidin aglycone with different sugar moieties varied in recovery within the gastrointestinal tract (GIT) with sambubiose>sambubiose-rhamnose=rutinose>>glucose. Complex ACNs containing di- or tri-glycosides disappeared more slowly than simple monoglycoside ACNs. Phenolic acids (protocatechuic acid and 3-hydroxybenzoic acid) were recovered in the GIT which appeared to be formed from ACNs. Homoprotocatechuic acid was a major phenolic acid detected in the cecum/colon. Cyanidin and other ACN monoglycosides were metabolized via methylation and glucuronidation as well as by formation of both derivatives on the same ACN molecule. Over 80% of the ACN compounds containing rutinose or sambubiose excreted in urine were excreted intact. The data clearly demonstrate that the sugar moieties can alter apparent absorption and metabolism of ACNs. |
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Characterization and Bioavailability of Flavonoid Glycosides
8:00 AM-12:10 PM, Sunday, August 19, 2007 BCEC -- 255, Oral
Division of Agricultural & Food Chemistry |