title: Inhibition of free radical initiated peroxidation of human erythrocyte ghosts by flavonols and their glycosides.
abstract: The in vitro peroxidation of human erythrocyte ghosts was used as a model to study the free radical-induced damage of biological membranes and the protective effect of flavonols and their glycosides, i.e., quercetin (Q), quercetin galactopyranoside (QG), quercetin rhamnopyranoside (QR), rutin (R), morin (MO), kaempferol (K) and kaempferol glucoside (KG). The peroxidation was initiated by a water-soluble free radical initiator 2,2'-azobis(2-methylpropionamidine) dihydrochloride (AMPAD) at physiological temperature, and monitored by oxygen uptake. Kinetic analysis of the peroxidation process demonstrates that these flavonols and their glycosides are effective antioxidants against AMPAD-initiated oxidative damage of human erythrocyte ghosts, and that the flavonols bearing ortho-dihydroxyl groups possess significantly higher antioxidant activity than those bearing no such functionalities and the glycosides are less active than their parent aglycones.
authors.affiliation: National Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, China.
authors.forename: Lifen
authors.initials: L
authors.lastname: Hou
authors.forename: Bo
authors.initials: B
authors.lastname: Zhou
authors.forename: Li
authors.initials: L
authors.lastname: Yang
authors.forename: Zhong-Li
authors.initials: ZL
authors.lastname: Liu
mesh_terms: D000578:Amidines / Q000737:chemistry; D000975:Antioxidants / Q000494:pharmacology*; D004910:Erythrocyte Membrane / Q000187:drug effects / Q000378:metabolism*; D004912:Erythrocytes / Q000187:drug effects; D005419:Flavonoids / Q000494:pharmacology; D044948:Flavonols / Q000494:pharmacology*; D005609:Free Radicals / Q000378:metabolism*; D006027:Glycosides / Q000494:pharmacology*; D006801:Humans; D044949:Kaempferols / Q000494:pharmacology; D007700:Kinetics; D015394:Molecular Structure; D010084:Oxidation-Reduction; D011794:Quercetin / Q000494:pharmacology; D012431:Rutin / Q000494:pharmacology; D047309:Flavones
chemical_list: D000578:Amidines; D000975:Antioxidants; D005419:Flavonoids; D044948:Flavonols; D005609:Free Radicals; D006027:Glycosides; D044949:Kaempferols; D011794:Quercetin; D012431:Rutin; C006552:kaempferol; C046728:2,2'-azobis(2-amidinopropane); C008548:morin; D047309:Flavones