【摘要】 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%。更多还原

【Abstract】 The preparation methods of immobilized β-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 β-glucosidase,and the optimized conditions by orthogonal experiments were as follows: the cross-linking time 3h,0.1% glutaraldehyde,1% sodium alginate,2% CaCl2.The immobilized β-glucosidase exhibited different properties from the free β-glucosidase in thermal and pH stabilities,while its optimal pH was 5.5 and optimal temperature was 70℃.Under this condition,the immobilized β-glucosidase remained 68.82% enzyme activity when storaged at 15℃ for 30 days.The optimal conditions for transformation ginsenoside Rg1 into ginsenoside F1 by immobilized β-glucosidase were determined as: the bearing capacity of the immobilized β-glucosidase was 3.76U/g immobilized enzyme carrier,the concentration of substrate was 0.2mg/mL,the transformational temperature was 40℃,the transformational duration was 2 days,the effective continuous transformational times were 4 rounds and the average transformational ratio for ginsenoside Rg1 was up to 80.49%.更多还原