Purification and properties of lipase from Tilapia intestine - Digestive enzyme of Tilapia - VI

Lipase of the intestine of Tilapia nilotica was purified by ammonium sulfat e precipitation, followed by ion-exchange chromatography (DEAE-cellulose), chromatofocusing (Polyexchanger PBE 94 ), and gel filtration (Sephadex G-10 0). The lipase was found to be a single band when examined by electrophoresis. The specific activity of the purified enzyme was 177 times higher than that of the crude extract. The lipase had a molecular weight of 46,000, showed the highest activity at pH 7.5 and 35 degreesC, and was stable at pH 6.5-8.5 and below 40 degreesC . The Km of the enzyme for olive oil was calculated to be 0.7 mM. Its activ ity was inhibited by Cu2+, Cd2+, Ni2+, Hg2+, PCMB, and CH2ICOOH. This enzyme specifically digested Tributyrin and Tricaproin, whereas it dig ested 1,2-diolein and 1-monoolein more than 1,3-diolein and 2-monoolein. Th e enzyme well decomposed soybean oil and coconut oil.