title: Antioxidant activity of flavonoids evaluated with myoglobin method.
abstract: Antioxidant activities of four flavonoids (rutin, quercetin, luteolin, and kaempferol) and two non-flavonoids (chlorogenic acid and pyrocatechol) against four reactive oxygen species (ROS) have been measured with a myoglobin method developed by our group. The myoglobin method uses the absorbance changes of myoglobin (a probe molecule) due to the reaction with the ROS as an indicator for the antioxidant activity measurement. Myoglobin protective ratio (MPR) was defined to express the antioxidant activities of the specimens. Antioxidant activities against hypochlorite ion, hydroxyl radical, peroxyl radical, and peroxynitrite were measured with the myoglobin method. The antioxidant activities were comprehensively evaluated by plotting MPR against four ROS and vitamin C equivalent concentration evaluated by DPPH quenching method in 5-axe cobweb charts. The four flavonoids show a very similar pattern in the 5-axe cobweb charts, while the patterns of two non-flavonoids are quite different from that of the flavonoids. This procedure combining the myoglobin method with the cobweb charts is useful in the evaluation of antioxidant activities of plant-derived food, and also can be extended to monitor antioxidant condition of media for plant cell cultures.
authors.affiliation: Department of Biosphere Sciences, School of Human Sciences, Kobe College, 4-1, Okadayama, Nishinomiya, Hyogo, 662-8505, Japan. terasima@mail.kobe-c.ac.jp
authors.forename: Masaaki
authors.initials: M
authors.lastname: Terashima
authors.forename: Yuri
authors.initials: Y
authors.lastname: Kakuno
authors.forename: Naruho
authors.initials: N
authors.lastname: Kitano
authors.forename: Chiharu
authors.initials: C
authors.lastname: Matsuoka
authors.forename: Mayumi
authors.initials: M
authors.lastname: Murase
authors.forename: Naoko
authors.initials: N
authors.lastname: Togo
authors.forename: Ryoko
authors.initials: R
authors.lastname: Watanabe
authors.forename: Saki
authors.initials: S
authors.lastname: Matsumura
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D001671:Biochemistry / Q000379:methods*; D001713:Biphenyl Compounds; D005419:Flavonoids / Q000378:metabolism*; D006736:Horses; D017665:Hydroxyl Radical; D006997:Hypochlorous Acid; D007477:Ions; D009211:Myoglobin / Q000378:metabolism*; D030421:Peroxynitrous Acid; D010851:Picrates
chemical_list: D000975:Antioxidants; D001713:Biphenyl Compounds; D005419:Flavonoids; D007477:Ions; D009211:Myoglobin; D010851:Picrates; D030421:Peroxynitrous Acid; D017665:Hydroxyl Radical; D006997:Hypochlorous Acid; C004931:1,1-diphenyl-2-picrylhydrazyl