本文探讨了β-葡萄糖苷酶的固定化方法,及利用固定化β-葡萄糖苷酶转化人参皂苷Rg1为人参皂苷F1的转化工艺.确定交联-包埋法为最佳固定化方法,应用正交实验得出最佳制备条件为:交联时间3h,戊二醛浓度0.1％,海藻酸钠浓度1％,CaCl2浓度2％.固定化酶与游离酶在热稳定性和pH值稳定性方面显示出不同的性质,其中固定化β-葡萄糖苷酶的最适反应温度为70℃,最适反应pH值为5.5.固定化β-葡萄糖苷酶在15℃环境中保存30d后,酶活回收率为68.82％.固定化β-葡萄糖苷酶转化人参皂苷Rg1为人参皂苷F1的转化条件为:固定化酶承载量为3.76U/g固定化酶载体,底物浓度为0.2mg/mL,转化温度为40℃,转化周期为2d,转化次数为4次,平均转化率为80.49％.%The preparation methods of immobilized P-glucosidase and the transformation of ginsenoside F1 from ginsenoside Rg1 by this immobilized enzyme were reported in this work. It showed that the Crosslink-embedding method was optimum for the immobilization of p-glucosidase, and the optimized conditions by orthogonal experiments were as follows: the cross-linking time 3h, 0.1% glutaraldehyde, 1% sodium alginate, 2% CaC2. The immobilized P-glucosidase exhibited different properties from the free P-glucosidase in thermal and pH stabilities, while its optimal pH was 5.5 and optimal temperature was 70°C. Under this condition, the immobilized β-ghicosidase remained 68.82% enzyme activity when storaged at 15°C for 30 days. The optimal conditions for transformation ginsenoside Rg, into ginsenoside F, by immobilized P-glucosidase were determined as: the bearing capacity of the immobilized P-glucosidase was 3.76U/g immobilized enzyme carrier, the concentration of substrate was 0.2mg/mL, the transformational temperature was 40 °C, the transformational duration was 2 days, the effective continuous transformational times were 4 rounds and the average transformational ratio for ginsenoside Rg, was up to 80.49%.
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