2010 Fiscal Year Final Research Report

Analysis of lipid-alkyl radical scavenging reactions of vitamin E

Research Project

Project/Area Number	20580125
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Single-year Grants
Section	一般
Research Field	Food science
Research Institution	Gifu University
Principal Investigator	YAMAUCHI Ryo Gifu University, 応用生物科学部, 教授 (50126760)
Project Period (FY)	2008 – 2010
Keywords	ビタミンE / α-トコフェロール / 脂質過酸化 / フリーラジカル
Research Abstract	Formation of alkyl radicals of unsaturated lipids is the first step of lipid peroxidation. We have studied the lipid-alkyl radical scavenging reactions of vitamin E (α-tocopherol, α-TH). When cholesteryl linoleate (ChL) hydroperoxides were reacted with α-TH at 100℃, two addition products were obtained as 6-O-epoxyChL-α-TH and 6-O-ChL-α-TH. Iron-catalyzed reaction of phosphatidylcholine (PC) hydroperoxides with α-TH under nitrogen gave the addition products, 6-O-epoxyPC-α-TH. A sensitive method using a high-performance liquid chromatography with post-column reduction using platinum as the catalyst followed by fluorescence detection has been developed for the quantification of the addition products of α-TH during the peroxidation of an emulsion of ChL and PC. The addition products of α-TH with alkyl and peroxyl radicals were detected when the emulsion was peroxidized. The results indicate that α-TH may react with lipid-alkyl radicals under oxygen-insufficient conditions.