The antioxidant action of N-acetylcysteine: its reaction with hydrogen peroxide, hydroxyl radical, superoxide, and hypochlorous acid.
N-acetylcysteine has been widely used as an antioxidant in vivo and in vitro. Its reaction with four oxidant species has therefore been examined. N-acetylcysteine is a powerful scavenger of hypochlorous acid (H--OCl); low concentrations are able to protect alpha 1-antiproteinase against inactivation by HOCl. N-acetylcysteine also reacts with hydroxyl radical with a rate constant of 1.36 X 10(10) M-1s-1, as determined by pulse radiolysis. It also reacts slowly with H2O2, but no reaction of N-acetylcysteine with superoxide (O2-) could be detected within the limits of our assay procedures.
Aruoma
O I
OI
Department of Biochemistry, University of London King's College Strand Campus, U.K.
Halliwell
B
B
Hoey
B M
BM
Butler
J
J
D000111:Acetylcysteine; D000975:Antioxidants; D001798:Blood Proteins / Q000378:metabolism; D005609:Free Radicals; D006861:Hydrogen Peroxide; D006878:Hydroxides; D017665:Hydroxyl Radical; D006997:Hypochlorous Acid / Q000494:pharmacology; D007700:Kinetics; D010196:Pancreatic Elastase / Q000037:antagonists & inhibitors; D011480:Protease Inhibitors / Q000378:metabolism; D013481:Superoxides; D000515:alpha 1-Antitrypsin
D000975:Antioxidants; D001798:Blood Proteins; D005609:Free Radicals; D006878:Hydroxides; D011480:Protease Inhibitors; D000515:alpha 1-Antitrypsin; D013481:Superoxides; D017665:Hydroxyl Radical; D006997:Hypochlorous Acid; D006861:Hydrogen Peroxide; D010196:Pancreatic Elastase; D000111:Acetylcysteine