Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Sensitive spectrophotometric method for the determination of superoxide dismutase activity in tissue extracts

Journal Article · · Anal. Biochem.; (United States)
Superoxide dismutase (EC 1.15.1.1) has been assayed by a spectrophotometric method based on the inhibition of a superoxide-driven NADH oxidation. The assay consists of a purely chemical reaction sequence which involves EDTA. Mn(II), mercaptoethanol, and molecular oxygen, requiring neither auxiliary enzymes nor sophisticated equipment. The method is very flexible and rapid and is applicable with high sensitivity to the determination of both pure and crude superoxide dismutase preparations. The decrease of the rate of NADH oxidation is a function of enzyme concentration, and saturation levels are attainable. Fifty percent inhibition, corresponding to one unit of the enzyme, is produced by approximately 15 ng of pure superoxide dismutase. Experiments on rat liver cytosol have shown the specificity of the method for superoxide dismutase. Moreover, common cellular components do not interfere with the measurement, except for hemoglobin when present at relatively high concentrations. The assay is performed at physiological pH and is unaffected by catalase.
Research Organization:
Universita di Firenze, Italy
OSTI ID:
5533630
Journal Information:
Anal. Biochem.; (United States), Journal Name: Anal. Biochem.; (United States) Vol. 154:2; ISSN ANBCA
Country of Publication:
United States
Language:
English

Similar Records

Induction and inactivation of catalase and superoxide dismutase of Escherichia coli by ozone
Journal Article · Tue Sep 01 00:00:00 EDT 1987 · Arch. Biochem. Biophys.; (United States) · OSTI ID:5833301

Catalase and superoxide dismutase in alfalfa root nodules. [Medicago sativa L]
Conference · Mon Mar 31 23:00:00 EST 1986 · Plant Physiol., Suppl.; (United States) · OSTI ID:5273174

Modifiers of free radicals inhibit in vitro the oncogenic actions of x-rays, bleomycin, and the tumor promoter 12-O-tetradecanoylphorbol 13-acetate
Journal Article · Mon Feb 28 23:00:00 EST 1983 · Proc. Natl. Acad. Sci. U.S.A.; (United States) · OSTI ID:5605352