响应面法优化酶法转化合成维生素C糖苷（AA-2G）条件的研究

采用Design—Expert软件的Central Composite Design（CCD）响应面设计对环糊精葡萄糖苷转移酶转化合成糖基抗坏血酸（AA-2G）的五个主要因素（转化时间、转化温度、pH、Vc浓度、β-环糊精浓度）进行了研究。采用降维分析方法对pH与转化时间、转化温度、Vc浓度、β-环糊精浓度以及反应温度与反应时间的交互作用对酶法转化合成AA-2G的影响进行了分析。建立了影响因素与响应值之间的回归方程，根据回归方程优化得到最佳转化条件为：转化时间25h，温度36．5℃，pH5．4，Vc72dL，β-环糊精55g／L。在此条件下，AA-2G的理论产量为10．06g／L，在验证实验中AA-2G的产量为9．76g／L，与预测的理论产量接近，比优化前提高了33％。

Process optimization of enzymatic glucopyranosyl-L-ascorbic acid(AA-2G)synthesis by response surface methodology

Response surface analysis （uniform precision of central composite design, Design-Expert software） was applied to optimize the five major factors （time, temperature, pH, Vc concentration and β-cyclodextrin concentration） for enzymatic synthesis of glucopyranosyl-L-ascorbie acid （AA-2G）. Dimensional analysis method was used to analyze the interaction of pH and time, temperature, Vc concentration, β-cyclodextrin concentration, as well as temperature and reaction time. The regression model was established and the optimal conditions were obtained via model analysis： time 25 h, temperature 36.5 ℃, pH 5.4, Vcconcentration 72 g/L, β-cyclodextrin concentration 55 g/L. Under the optimal con- ditions, the theoretical AA-2G production was 10.06 g/L and in the validation experiments AA-2G production reached 9.76 g/L, which was increased by 33 % in comparison with that of the control without optimization.