title: Evaluation of free radical scavenging activities of antioxidants with an H(2)O(2)/NaOH/DMSO system by electron spin resonance.
abstract: An H(2)O(2)/NaOH/DMSO system has been developed for the formation of three free radicals, and the application of the system was examined with the antioxidants ascorbic acid and tocopherol. Superoxide anion, hydroxyl radical,and methyl radical are simultaneously generated in this system. The scavenging activity of ascorbic acid and tocopherol for these radicals was estimated by 5, 5'-dimethyl-1-pyrroline-N-oxide spin trapping electron spin resonance. Both water-soluble and oil-soluble antioxidants could be evaluated by using this system. Ascorbic acid specifically inhibited the superoxide anion and hydroxyl radical, whereas tocopherol suppressed the methyl radical.
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmaceutical Science, Hoshi University, Ebara 2-4-41, Shinagawa-ku, Tokyo 142-8501, Japan. yosimura@hoshi.ac.jp
authors.forename: Y
authors.initials: Y
authors.lastname: Yoshimura
authors.forename: T
authors.initials: T
authors.lastname: Inomata
authors.forename: H
authors.initials: H
authors.lastname: Nakazawa
authors.forename: H
authors.initials: H
authors.lastname: Kubo
authors.forename: F
authors.initials: F
authors.lastname: Yamaguchi
authors.forename: T
authors.initials: T
authors.lastname: Ariga
mesh_terms: D000975:Antioxidants / Q000737:chemistry*; D004121:Dimethyl Sulfoxide; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods*; D005609:Free Radicals; D006861:Hydrogen Peroxide; D012972:Sodium Hydroxide
chemical_list: D000975:Antioxidants; D005609:Free Radicals; D012972:Sodium Hydroxide; D006861:Hydrogen Peroxide; D004121:Dimethyl Sulfoxide