Absorption and metabolism of quercetin glucosides after the ingestion of onions by human volunteers

Crozier, Alan and Mullen, William (2005) Absorption and metabolism of quercetin glucosides after the ingestion of onions by human volunteers. [Proceedings Paper]

Onions containing 275 μmoles of flavonols, principally quercetin-4'- glucoside and quercetin-3,4'-diglucoside, was fed to human volunteers after which plasma and urine were collected over a 24 h period. Sample were analysed by HPLC with diode array and tandem mass spectrometric detection. Five flavonol metabolites, quercetin-3'-sulfate, quercetin-3- glucuronide, isorhamnetin-3-glucuronide, a quercetin diglucuronide and a quercetin glucuronide sulfate, were detected in plasma in quantifiable amounts together with trace quantities of six other metabolites. Sub-μM peak plasma concentrations (Cmax) of quercetin-3'-sulfate, the major metabolite, quercetin-3-glucuronide, isorhamnetin-3-glucuronide and quercetin diglucuronide were observed 0.6-0.8 h after ingestion. In contrast, the Cmax of the quercetin glucuronide sulfate was 2.5 h. The elimination half-lives (T12) of quercetin-3'-sulfate, quercetin-3-glucuronide and quercetin diglucuronide were1.71, 2.33 and 1.76 h respectively while the T1/2 of isorhamnetin-3-glucuronide was 5.34 h and that of the quercetin glucuronide sulfate was 4.54 h. The profile of metabolites excreted in urine was markedly different to that of plasma with many of the major urinary components, including quercetin-3'-glucuronide, two quercetin glucoside sulfates and a methylquercetin diglucuronide, being either absent or present in the bloodstream in only trace quantities. This is indicative of substantial phase II metabolism. Total urinary excretion of quercetin metabolites was 12.9 µ moles which corresponds to 4.7% of intake.

Full text available from:

Abstract

Onions containing 275 μmoles of flavonols, principally quercetin-4'- glucoside and quercetin-3,4'-diglucoside, was fed to human volunteers after which plasma and urine were collected over a 24 h period. Sample were analysed by HPLC with diode array and tandem mass spectrometric detection. Five flavonol metabolites, quercetin-3'-sulfate, quercetin-3- glucuronide, isorhamnetin-3-glucuronide, a quercetin diglucuronide and a quercetin glucuronide sulfate, were detected in plasma in quantifiable amounts together with trace quantities of six other metabolites. Sub-μM peak plasma concentrations (Cmax) of quercetin-3'-sulfate, the major metabolite, quercetin-3-glucuronide, isorhamnetin-3-glucuronide and quercetin diglucuronide were observed 0.6-0.8 h after ingestion. In contrast, the Cmax of the quercetin glucuronide sulfate was 2.5 h. The elimination half-lives (T12) of quercetin-3'-sulfate, quercetin-3-glucuronide and quercetin diglucuronide were1.71, 2.33 and 1.76 h respectively while the T1/2 of isorhamnetin-3-glucuronide was 5.34 h and that of the quercetin glucuronide sulfate was 4.54 h. The profile of metabolites excreted in urine was markedly different to that of plasma with many of the major urinary components, including quercetin-3'-glucuronide, two quercetin glucoside sulfates and a methylquercetin diglucuronide, being either absent or present in the bloodstream in only trace quantities. This is indicative of substantial phase II metabolism. Total urinary excretion of quercetin metabolites was 12.9 µ moles which corresponds to 4.7% of intake.

[error in script]

Item Type:	Proceedings Paper
Additional Information:	Available at Perpustakaan Sultan Abdul Samad, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia. TP684 P3I61 2005 Call Number
AGROVOC Term:	onions
AGROVOC Term:	quercetin
AGROVOC Term:	functional foods
AGROVOC Term:	human nutrition
AGROVOC Term:	bioavailability
AGROVOC Term:	metabolism
AGROVOC Term:	analysis
AGROVOC Term:	sampling
AGROVOC Term:	humans
AGROVOC Term:	human health
Geographical Term:	United Kingdom
Depositing User:	Nor Hasnita Abdul Samat
Date Deposited:	02 Nov 2025 02:38
Last Modified:	10 Nov 2025 01:10
URI:	http://webagris.upm.edu.my/id/eprint/1232

Actions (login required)

View Item