Principle of the Procedure

Superoxide dismutases (SOD, EC1.15.1.1) are enzymes that catalyze the dismutation of superoxide anion into O2 and H2O2. They are an important antioxidant defense against the toxicity of superoxide radical in all cells exposed to O2. Aberrant SOD activities have been linked to diseases such as amyotrophic lateral sclerosis, perinatal lethality, neural disorders and cancer. There are three major families of superoxide dismutase: Cu/Zn, Fe/Mn, and the Ni type. Three forms of superoxide dismutase are present in humans. SOD1 is located in the cytoplasm, SOD2 in the mitochondria, and SOD3 is extracellular.This kit provides a simple and easy assay for the quantitative determination of SOD enzyme activity in serum, plasma, animal and plant tissues, cells lysates and other biological fluids. In the assay, superoxide anion (O2-) is provided by xanthine oxidase (XO) catalyzed reaction. O2- reacts with a tetrazolium salt WST-8 dye to form a water-soluble colored formazan product. SOD scavenges the O2- thus less O2- is available for the chromogenic reaction. This inhibition activity of SOD is measured by colorimetric method at 450 nm. The activity of SOD was negatively correlated with the amount of formazan.