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Abstract : |
Ionic effect on the degradation of oil seeds (Brassica napus L) storage lipid was investigated during germination. Lipid degradating enzyme lipase was identified in germinating Brassica napus L and the enzyme was purified to homogeneity by extraction, Sephadex G-50, DEAE and CM-cellulose column chromatography. The enzyme was purified to 67.59 fold with the final specific activity of 39.10 mmol min-1 mg-1 at 37C using triolein as a substrate. The purified enzyme showed a single band when it was subjected to SDS / PAGE electrophoresis. The SDS/PAGE electrophoresis indicated a molecular mass of 34 kDa for this lipase which corresponding to the high-resolution gel filtration. The optimum pH and temperature for hydrolysis of Oleic acid were 7.0 and 37C, respectively. In the presence of Ca 2+ and Bi 3+, the lipase activity was dramatically enhanced by 165 and 124%, respectively. Fe3+, Fe2+, Zn2+, Hg2+ and Cu2+ could inhibit this lipase but Al 3+, Pb 2+ showed no influence on hydrolysis activity. Km of this enzyme was 0.23 mM., Ionic effect on the degradation of oil seeds (Brassica napus L) storage lipid was investigated during germination. Lipid degradating enzyme lipase was identified in germinating Brassica napus L and the enzyme was purified to homogeneity by extraction, Sephadex G-50, DEAE and CM-cellulose column chromatography. The enzyme was purified to 67.59 fold with the final specific activity of 39.10 mmol min-1 mg-1 at 37?C using triolein as a substrate. The purified enzyme showed a single band when it was subjected to SDS / PAGE electrophoresis. The SDS/PAGE electrophoresis indicated a molecular mass of 34 kDa for this lipase which corresponding to the high-resolution gel filtration. The optimum pH and temperature for hydrolysis of Oleic acid were 7.0 and 37?C, respectively. In the presence of Ca 2+ and Bi 3+, the lipase activity was dramatically enhanced by 165 and 124%, respectively. Fe3+, Fe2+, Zn2+, Hg2+ and Cu2+ could inhibit this lipase but Al 3+, Pb 2+ showed no influence on hydrolysis activity. Km of this enzyme was 0.23 mM., |
