Extraction, partial purification and characterization of acidic peroxidase from cabbage leaves (Brasicca olearacea var. capitata)

The present work deals with extraction of cabbage peroxidase (CP) from fresh cabbage leaves and subsequent purification using ammonium sulphate (80% w/v) precipitation. The peroxidase extraction has been carried out by screening two different cabbage and then different parameters like different buffer systems, strength of buffers, buffer volumes, grinding time and cabbage leaves weight ratio to buffer volumes were optimized. The purified peroxidase showed maximum activity at pH 5.5 and at temperature 55 °C. The enzyme action followed the Michelis–Menton kinetics and gave a Km of 0.7018 mg/ml for Guaiacol oxidation over different concentrations (0 – 10 mg/ml) at pH 5.0 and Vmax was obtained as 0.6498 mg/min.ml. The molecular weight of the partially purified enzyme was found to be about 67,000 Daltons using SDS-PAGE and zymogram method.