@inproceedings{oai:repo.qst.go.jp:00054221,
 author = {Nakanishi, Ikuo and Uto, Yoshihiro and Ohkubo, Kei and Matsumoto, Kenichiro and Hori, Hitoshi and Fukuhara, Kiyoshi and Okuda, Haruhiro and Ikota, Nobuo and Fukuzumi, Shunichi and Ozawa, Toshihiko and Anzai, Kazunori and 中西 郁夫 and 松本 謙一郎 and 小澤 俊彦 and 安西 和紀},
 book = {Free Radical Biology and Medicine},
 issue = {Supplement 1},
 month = {Nov},
 note = {It is known that 2-methyl-6-phytylhydroquinone (2-MePHQ) and 2,3-dimethyl-6-phytylhydroquinone (2,3-Me2PHQ) are formed as precursors in the biosynthetic process of vitamin E.  However, very little is known about the antioxidative activity of these vitamin E precursors.  Thus, we determined the scavenging rate constants of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical by 2-MePHQ, 2,3-Me2PHQ, and their synthetic analogues, 2,5-dimethyl-6-phytylhydroquinone (2,5-Me2PHQ) and 2,3,5-trimethyl-6-phytylhydroquinone (2,3,5-Me3PHQ) in deaerated ethanol at 298 K using the stopped-flow technique.  2,3,5-Me3PHQ and 2,3-Me2PHQ, which have a methyl group at the C-3 position, showed a stronger DPPH radical-scavenging activity than alpha-tocopherol.  The mechanism of the DPPH radical-scavenging reaction by the hydroquinones will also be discussed based on the kinetic and theoretical results obtained in this study.},
 pages = {S191--S191},
 title = {Radical-Scavenging Activity of Biosynthetic Precursors of Vitamin E and Their Derivatives},
 volume = {47},
 year = {2009}
}