4.6. Assays of Guaiacol Peroxidase (POX, E.C.1.11.1.7) and Superoxide Dismutase (SOD, E.C.1.15.1.1) Activities

The activities of enzymes that detoxify H₂O₂ (POX, E.C.1.11.1.7) and ˙O²¯ (SOD, E.C.1.15.1.1) were tested. The activity of guaiacol peroxidase (G-POX) was established according to Frič and Fuchs [67], and the activity of superoxide dismutase (SOD) according to Beauchamp and Fridovich [68]. One unit of SOD activity is the amount of proteins required to inhibit 50% initial reduction in nitrotetrazolium blue chloride (NBT) under the light. G-POX activity is expressed in µM of tetraguaiacol min⁻¹mg⁻¹ by molar extinction coefficient of tetraguaiacol (26.6). All chemicals were purchased from Sigma-Aldrich Co.