The activity of peroxidase (POD) in cabbage was evaluated using
spectrophotometric method. The enzyme was extracted from the cabbage leaves
with 0.1 M phosphate buffer solution pH 7. 0 . POD activity was determined using
(O-dianisidine) as a substrate. The effects of the amounts of enzyme extract,
substrate concentration, pH and temperature were investigated. The highest activity
of POD was recored at 2 mg/ml. The highest activity of POD was optimized with
16 mM O-dianisidine, The optimum pH was 7.0 for POD , The optimum
temperature was 30°C for POD. These optimum conditions were used to
determined the enzyme activities in cabbage sample. Acetone fractionated
peroxidase from crude extract of Brassica oleracea leaves (Cabbage) was purified
on DEAE-Cellulose chromatographic columns. The specific activity of purified
POD is 103.70 (U/mg) ،which is 5.37 times more than the crude extract with
28.72% recovery. Maximum pH, thermal activity and stability of this purified
enzyme are also determined were 40°C