Anti-oxidative stress enzymes in Pleurotus ostreatus

Pleurotus ostreatus is an edible white-rot basidiomycete with medicinal and bioremediation properties. In this research, the activity of key intracellular anti-oxidative stress enzymes, superoxide dismutase (SOD), catalase (CAT) and peroxidase (POX), was investigated and characterized in the mushroom. A Pleurotus ostreatus homogenate was centrifuged at 3,000 g for 10 min; the supernatant was centrifuged at 35,000 g for 30 min, and the new supernatant obtained, called “crude extract” was used for our studies. Results showed that up to 7.4 units SOD, 11.7 units CAT and 0.037 units POX were detectable per mg protein in Pleurotus ostreatus extract. All three enzymes were sensitive to KCN. Non-denaturing polyacrylamide gel electrophoresis of the extract, followed by activity staining, revealed one SOD band (estimated M.W. 44 kD), one CAT band (estimated M.W. 280 kD) and three POX bands (estimated M.W. 77, 65, and 60 kD, respectively).