Purification and Biochemical Characterization of Peroxidase Isolated from White Cabbage (Brassica Oleracea var. capitata f. alba)

Peroxidase enzyme was purified for the first time from white cabbage (Brassica oleracea var. capitata f. alba) in a single step using affinity chromatography and some biochemical characteristics of the purified enzyme were determined. The peroxidase was purified 24.7-fold with an overall recovery of 4.3% and a specific activity of 964.5. The molecular weight of the purified peroxidase was approximately 73.2 kDa as calculated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and it showed maximum activity at pH 6.5 and 30°C. For the guaiacol substrate, the K_M and V_max values were found as 3.19 mM and 0.2 EU/mL, respectively. Additionally, the IC₅₀ and K_i values were determined as 0.517 and 0.994 ± 0.453 mM, respectively, for 4-aminobenzohydrazide. 4-amino benzohydrazide showed non-competitive inhibition.