中温碱性脂肪酶的研究——Ⅲ.扩展青霉PF868变株碱性脂肪酶的纯化及其酶学性质

Studies on Alkaline-Mesophile Lipase Ⅲ . Purification and Some Properties of Alkaline Lipase from Penicillium expansum PF868

扩展青霉PF868变株发酵液经硫酸铵盐析和Sephadex-G-200及Sepharose4B柱层析纯化,获得纯化倍数为32.4的酶粉.该酶分子量为23442Dal.酶学特性表明:该酶的最适作用温度为32℃,50℃保温30min仍保留50%酶活性,最适pH为9.0,作用pH稳定范围在7.0—10.0之间.Ca^(2+)Mg^(2+)对酶有激活作用.Fe^(2+)、Cu^(2+)和Mn^(2+)对酶活力有抑制作用.

Alkaline lipase from P. expansum PF868 was purified 32. 4-fold with a yield of 25.6%. The purification procedure included ammonium sulfate fractionation and column chromatography on Sephadex G-200 and Sepharose 4B. The molecu-lar weight of the enzyme was determined by SDS-PAGE to be about 23442 Dal. The optimal pH and temperature for hydrolysis of olive oil were 9.0 and 35℃ respectively. The enzyme activity was stimulated by Ca2+ and Mg2+, but was inhibited by Fe2+、 Cu2+ and Mn2+. More than 50% of the original activity was maintained by heating at 50℃ for 30 minutes.