title: The inhibitory effect of luteolin-7-O-glucoside on the formation of pentyl and 7-carboxyheptyl radicals from 13-hydroperoxy-9,11-octadecadienoic acid in the presence of iron(II) ions.
abstract: A flavone glucoside, luteolin-7-O-glucoside (luteolin-7-G) inhibited the formation of pentyl and 7-carboxyheptyl radicals in the reaction of 13-hydroperoxy-9,11-octadecadienoic (13-HPODE) acid with iron(II) ions. The inhibitory effect of luteolin-7-G was diminished in the presence of EDTA. These results indicated that the inhibitory effects of luteolin-7-G occur partly through the chelation of iron ions. Measurement of visible spectra also showed that luteolin-7-G chelates iron ions. On the other hand, luteolin-7-G did not inhibit the reaction under anaerobic conditions, suggesting that oxygen molecules participate in the inhibition. Oxygen consumption measurements showed that the luteolin-7-G/iron ion complexes react with oxygen molecules in competition with 13-HPODE acid, and free iron ions exclusively react with 13-HPODE acid. The reaction of luteolin-7-G/iron ion complexes with oxygen molecules possibly diminishes the formation of pentyl and 7-carboxyheptyl radicals.
authors.affiliation: Department of Chemistry, Wakayama Medical University, 811-1 Kimiidera, Wakayama 641-8509, Japan. chem1@wakayama-med.ac.jp
authors.forename: Hideo
authors.initials: H
authors.lastname: Iwahashi
authors.forename: Kayo
authors.initials: K
authors.lastname: Akata
authors.forename: Atsuko
authors.initials: A
authors.lastname: Sunaga
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Tone
authors.forename: Noriko
authors.initials: N
authors.lastname: Yamada
authors.forename: Keiko
authors.initials: K
authors.lastname: Iijima
mesh_terms: D002851:Chromatography, High Pressure Liquid; D005231:Fatty Acids, Unsaturated / Q000737:chemistry; D005609:Free Radicals / Q000737:chemistry*; D005960:Glucosides / Q000737:chemistry* / Q000494:pharmacology; D007501:Iron / Q000737:chemistry* / Q000494:pharmacology; D008041:Linoleic Acids / Q000737:chemistry*; D008054:Lipid Peroxides / Q000737:chemistry*; D047311:Luteolin / Q000737:chemistry* / Q000494:pharmacology; D015394:Molecular Structure; D010100:Oxygen / Q000737:chemistry; D013057:Spectrum Analysis
chemical_list: C092671:13-oxotrideca-9,11-dienoic acid; D005231:Fatty Acids, Unsaturated; D005609:Free Radicals; D005960:Glucosides; D008041:Linoleic Acids; D008054:Lipid Peroxides; C038649:13-hydroperoxy-9,11-octadecadienoic acid; C066408:luteolin-7-glucoside; D007501:Iron; D047311:Luteolin; D010100:Oxygen