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Abstract ?The present results showed that the maximum activity of both phytase and acid phosphatase from marrow cotyledons was observed on the 5th day of seed germination. NaCl and sorbitol induced the activities of phytase and acid phosphatase in marrow cotyledons. NaCl or sorbitol did not reduce the level of Pi in marrow cotyledons. The induction of phytase or acid phosphatase activities by NaCl and sorbitol was almost completely blocked by CHI and this indicated that such induction of both enzymes is due to de novo synthesis of the two enzymes. The activities of phytase and acid phosphatase were elevated following application of exogenous JA. EGTA, LaCl3 and verapamil inhibited the induction of phytase or acid phosphatase by JA. The activities of phytase and acid phosphatase were increased in presence of either Triton X100 or Nonidet P40 as detergents. These two compounds increased the activities of the two enzymes at 0.2 % (v/v), 0.5 % (v/v) and 1.0 % (v/v) and it has been noted that 1.0 % (v/v) was the most effective concentration. Benzyladenine (BA) at either 105 or 103 M induced the activities of phytase and acid phosphatase. However, coumarin at 105 or 103 M resulted in the inhibition of phytase but did not affect acid phosphatase. The three polyamines: spermine, spermidine and putrescine inhibited both phytase and acid phosphatase at the different concentrations tested (15 mM). Spermidine was the most potent inhibitor of the two enzymes throughout the experimental period. Phytase was purified with specific activity of 260 U mg1 protein from marrow cotyledons by ammonium sulphate fractionation, DEAE cellulose column and hydroxylapatite column. The fold of purification of phytase was 1181.8fold. The purification of acid phosphatase included precipitation of the crude extract by ammonium sulphate, DEAEcellulose column and SephacrylS300 columns. The specific activity of acid phosphatase was 213 U mg1 protein. |