title: [Antioxidant activity of oxygen-containing aromatic compounds].
abstract: Inhibition efficiency (antioxidant activity) of 26 oxygen-containing aromatic compounds was studied in methemalbumin-H202-o-phenylenediamine (PDA) or tetramethylbenzidine (TMB) pseudoperoxidase system at 20 degrees C in buffered physiological solution (pH 7.4) containing 6% DM F and 0.25% DMSO. The inhibitor's efficiency was quantitatively characterized by the inhibition constants (Ki, microM) or the inhibition degree (%). Ki values varied in the range of4 to 500 microM and were influenced by a substrate, the structure of an inhibitor, hydroxyl groups, electron-donating substituents in aromatic ring, and steric hindrances. The type of inhibition at cooxidation of eight pairs was noncompetitive, and that of five pairs was mixed and determined by the substrate nature and the inhibitor structure. Lignin phenolic compounds ofguaiacyl and syringal series exhibited high antioxidant activity (Ki in the range of 10-300 microM), and their efficiency decreased in the following order: caffeic acid > synapaldehyde > syringic acid > coniferyl aldehyde > para-hydroxycou maric acid.
authors.forename: M V
authors.initials: MV
authors.lastname: Potapovich
authors.forename: V P
authors.initials: VP
authors.lastname: Kurchenko
authors.forename: D I
authors.initials: DI
authors.lastname: Metelitsa
authors.forename: O I
authors.initials: OI
authors.lastname: Shadyro
mesh_terms: D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology*; D001560:Benzidines / Q000737:chemistry / Q000378:metabolism; D002384:Catalysis / Q000187:drug effects; D006841:Hydrocarbons, Aromatic / Q000737:chemistry / Q000494:pharmacology*; D006861:Hydrogen Peroxide / Q000737:chemistry / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008031:Lignin / Q000737:chemistry / Q000494:pharmacology*; D008705:Methemalbumin / Q000737:chemistry / Q000378:metabolism; D018716:Molecular Mimicry; D010084:Oxidation-Reduction; D010100:Oxygen; D010544:Peroxidases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D010636:Phenols / Q000737:chemistry / Q000494:pharmacology*; D010655:Phenylenediamines / Q000737:chemistry / Q000378:metabolism; D012996:Solutions / Q000378:metabolism; D012997:Solvents / Q000737:chemistry
chemical_list: D000975:Antioxidants; D001560:Benzidines; D006841:Hydrocarbons, Aromatic; D008705:Methemalbumin; D010636:Phenols; D010655:Phenylenediamines; D012996:Solutions; D012997:Solvents; C021758:3,3',5,5'-tetramethylbenzidine; C034193:1,2-diaminobenzene; D008031:Lignin; D006861:Hydrogen Peroxide; D010544:Peroxidases; D010100:Oxygen