【摘要】 以壳聚糖为载体,用物理吸附固定化脂肪酶,对影响固定化过程的各种因素进行了考察,确定了最优条件,并比较了游离酶和固定化酶的最适温度、pH、酶的热稳定性以及表观Km。固定化酶水解的最适pH(pH7.0)稍低于游离酶(pH8.0),最适温度为50°C(游离酶为40°C)。固定化酶在50°C的半衰期(0.96h)是游离酶(0.32h)的3倍,在4°C的冰箱中贮存3个月活力变化很小。更多还原

【Abstract】 Lipase (EC3.1.1.3) from Candida sp. was immobilized on chitosan by physical adsorption. In this article, different factors that influenced the immobilization were investigated, and the optimum conditions were ascertained. Comparative studies of pH, temperature and thermal stability between free lipase and immobilized lipase were conducted. As a result, the optimum pH(7.0) of the immobilized lipase was lower than that of the soluble lipase (8.0). The optimum reaction temperature shifted from 40(°C) for the free lipase to 50(°C) for the immobilized lipase. The patterns of thermal stability indicated that the immobilization process tends to stabilize the enzyme. Compared with the half-life(0.32 h) of the soluble free (lipase) at 50(°C), the half-life(0.96 h) of the immobilized lipase increased three times. The activity of immobilized lipase changed slightly after 3 months storage at 4(°C).更多还原