Superoxide--driven oxidation of quercetin and a simple sensitive assay for determination of superoxide dismutase
Kostyuk, V.A.; Potapovich, A.I.
Biochemistry International 19(5): 1117-1124
1989
ISSN/ISBN: 0158-5231 PMID: 2561443 Document Number: 332763
Oxidation of quercetin at pH 10 was shown to be a free radical chain reaction involving superoxide and hence inhibitable by superoxide dismutase (SOD) (EC 1.15.1.1). The degree of inhibition of quercetin oxidation was a function of SOD concentration, and fifty percent inhibition was produced by approximately 1.5 ng/ml of pure enzyme. This reaction proved to be a very useful tool for a rapid and highly sensitive measurement of SOD in crude tissue extracts and other biological samples.