Extraction condition of protease frombroccoli (Brassicaoleracea var italic) and study of Biochemical Characteristic fromthe selectedsource

Abstract

Four species were tested for the Brassicaceae , Brassicaoleracea var italic, Brassicaoleracea var botrytis, Brassicarapa var rapa , Brassicaoleracea var captata.to investigate the presence of protease. The result showed that broccoli possessed a high level of protease ,which because it has a high specific activity of the enzyme ,so it was chosen as a source of enzyme extraction . the best condition to extraction protease from broccoli was by using sodium phosphate buffer (0.1M,pH 7.5) reaching an specific activity 70.769U/mg .the enzyme was extracted with different extraction ratios of 1:1, 2:1, 4:1, 6:1,8:1, 10:1(v:w) and the best ratio was 1:1(v:w) to specific activity 70.6 U/mg .the enzyme extraction in different concentration 0.05,0.1,0.2,0.4 the highest specific activity were 76.4when enzyme extract in 0.1M. finally the enzyme was extracted with different time intervals of 5,10,15,20 ,and the best time period for extracting was 5 min with specific activity 76.06 U/mg .the enzyme purified from broccoli by several step concentration by ammonium sulfate at saturation 75% the enzyme reached activity 30.2U/m,purified fold 1.63 and yield 74.60 .The second step was purified by DEAE-Cellulose column , the enzyme reached activity 20.1U/ml  and yield 69.51.The optimum pH for the enzyme activity and stability were 7.5 for 30 minute and 7-8.5 respectively . The optimum temperature of the enzyme activity 35 C⁰ for 30 minutes and that for stability was 25-40C⁰ for 30 minutes.