title: Enhancing effect of lipids and emulsifiers on the accumulation of quercetin metabolites in blood plasma after the short-term ingestion of onion by rats.
abstract: The effects of co-ingested lipids and emulsifiers on the accumulation of quercetin metabolites in blood plasma after the short-term ingestion of onion by rats were investigated. Plasma extracts of rats that had been fed onion-containing diets for one and two weeks were analyzed by HPLC with electrochemical detection after a treatment with sulfatase/beta-glucuronidase. Almost all of the quercetin metabolites in the plasma were sulfate/glucuronide conjugates of quercetin and isorhamnetin. More than 4.6% (w/w) of soybean oil in the diets significantly enhanced the accumulation of quercetin metabolites in the plasma. Fish oil and beef tallow increased this to an extent similar to that with soybean oil, and lecithin was more effective than the other three lipids. Two emulsifiers, sodium caseinate and sucrose fatty acid ester, also showed an enhancing effect on the accumulation of quercetin metabolites. These results indicate that co-ingested lipids and emulsifiers could enhance the bioavailability of quercetin glucosides in onion.
authors.affiliation: National Institute of Vegetable and Tea Science, National Agricultural Research Organization, Ano, Mie, Japan. azumak@affrc.go.jp
authors.forename: Keiko
authors.initials: K
authors.lastname: Azuma
authors.forename: Katsunari
authors.initials: K
authors.lastname: Ippoushi
authors.forename: Hidekazu
authors.initials: H
authors.lastname: Ito
authors.forename: Hideki
authors.initials: H
authors.lastname: Horie
authors.forename: Junji
authors.initials: J
authors.lastname: Terao
mesh_terms: D000818:Animals; D002364:Caseins / Q000494:pharmacology; D002851:Chromatography, High Pressure Liquid; D045703:Emulsifying Agents / Q000494:pharmacology*; D005223:Fats / Q000378:metabolism; D044948:Flavonols / Q000032:analysis* / Q000097:blood; D005960:Glucosides / Q000032:analysis / Q000097:blood; D007408:Intestinal Absorption / Q000187:drug effects / Q000502:physiology; D050356:Lipid Metabolism; D008297:Male; D019697:Onions / Q000737:chemistry*; D011794:Quercetin / Q000032:analysis* / Q000097:blood / Q000031:analogs & derivatives; D051381:Rats; D017208:Rats, Wistar; D013024:Soybean Oil / Q000378:metabolism; D001617:beta-Glucosidase / Q000378:metabolism
chemical_list: D002364:Caseins; D045703:Emulsifying Agents; D005223:Fats; D044948:Flavonols; D005960:Glucosides; C047368:3-methylquercetin; D013024:Soybean Oil; C013698:tallow; D011794:Quercetin; D001617:beta-Glucosidase