Separation of Lipase from Karnel of Pistacia khinjuke and Determination of it's Affinity Toward some Inhibitors in Mice In vivo and In vitro

The study included the purification of lipase from Pistacia khinjuke by the application of the ammonium sulfate precipitation (70%), dialysis, ion exchange chromatography and finally slab electrophoresis techniques. One isoenzyme was obtained having a molecular weight of 43597 dalton and specific activity of 3-10 152 unit / mg protein. The maximum lipase activity was obtained at pH 7.5, temperature 40 C. The maximum velocity (Vmax) was 0.142 unit/ml/min and Km value was 0.666 mM. The type and ability inhibition of lipase was tested in presence of quercitine rutinoside and melatonine. The inhibition type was noncompetitive and the inhibition constant Ki values for the two inhibitors were 1.025 and 1.006 mM, respectively.
The lipase affinity of normal and induced diabetic mice serum toward these compounds was tested. The treatment of animals by a dose of 523.3 mg quercitine rutinoside / Kg of body weight showed a significant decrease in lipase activity, but an insignificant decrease with a dose of 8 mg melatonine / Kg of body weight. The treatment of animals by these compounds led to a significant decrease in glucose, total cholesterol and ratio of total cholesterol/HDL-C levels, but a significant increase in HDL-C in serum of normal and induced diabetic mice. The inhibitory effect of quercitine rutinoside and melatonine toward lipase and biochemical parameters' levels studied may help in using these compounds as natural inhibiting drugs.