Some kinetic properties of hepatic lipase of Oncorhynchus mykisswere investigated. Hepatic triacylglycerol lipase was found to be located in the cytosolic fraction of the cell. Optimal activity of hepatic lipase occurred at pH 8.00 and 32 °C. When pNPA was used as a substrate, Vmax and Km values of hepatic lipase were estimated as 0.40 U/mg protein and 0.12 mM pNPA respectively. A stimulating effect of monovalent (NaCl and KCl) and divalent (CaCl 2 and MgCl 2 ) metal ions on hepatic lipase activity was determined. The bile salts, Na-taurodeoxycholate and Na-deoxycholate, were determined to inhibit hepatic lipase activities. A chelating agent, EDTA, did not affect the activity of the lipase enzyme up to 4 mM whereas an increase in the activity of the enzyme was established with a 5 mM concentration.

Some kinetic properties of hepatic lipase of Oncorhynchus mykisswere investigated. Hepatic triacylglycerol lipase was found to be located in the cytosolic fraction of the cell. Optimal activity of hepatic lipase occurred at pH 8.00 and 32 °C. When pNPA was used as a substrate, Vmax and Km values of hepatic lipase were estimated as 0.40 U/mg protein and 0.12 mM pNPA respectively. A stimulating effect of monovalent (NaCl and KCl) and divalent (CaCl 2 and MgCl 2 ) metal ions on hepatic lipase activity was determined. The bile salts, Na-taurodeoxycholate and Na-deoxycholate, were determined to inhibit hepatic lipase activities. A chelating agent, EDTA, did not affect the activity of the lipase enzyme up to 4 mM whereas an increase in the activity of the enzyme was established with a 5 mM concentration.