酶法合成2-氧-α-D-葡萄糖基-L-抗坏血酸(AA-2G)条件的研究

采用单因素优化法对环糊精葡萄糖苷转移酶(CGTase)合成糖基抗坏血酸(AA-2G)条件进行优化,AA-2G的产量为2.76 g/L,比未优化前0.46g/L提高了500%。再采用响应面法对AA-2G合成条件进行优化。由Plackett-Burman法筛选出三个主要因素为:pH、V_C和麦芽糊精浓度;由最陡爬坡实验得出最佳响应面区域;最后由Box-Behnken实验,得到最优条件为:pH 5.51,V_C36.16g/L,麦芽糊精28.54 g/L,转化时间24 h,温度37℃。在此条件下,AA-2G的理论产量为3.15 g/L,通过验证实验,得出AA-2G的产量为3.13 g/L,与预测的理论值接近,比单因素优化的结果(2.76g/L)提高了14%。

Optimization of synthesis 2-O-alpha-D-glucopyranosyl-L-ascorbic acid by using response surface methodology

The synthesis of 2-O-alpha-D-glycosyl-L-ascorbic-acid （AA-2G） by using cyclodextrin glucosidase was optimized through the single factor experiment. AA-2G production was as high as 2.76 g/L, which was increased by 500% in comparison with the control （0.46 g/L） before optimization. Then the synthesis conditions of AA-2G were optimized by using response surface and three main factors such as pH, the concentration of Vc and the concentration of maltodextrin were obtained by Plaekett- Burman method. The steepest ascent experiment was used to derive the optimum response sur- face area and Box-Behnken experimental design was used to get the optimum conditions of the various factors. The opti- mum conditions were as follows ： pH 5.51, Vc concentration 36.16 g/L, maltodextrin concentration 28.54 g/L, time 24 h and temperature 37 ℃. Under the optimum conditions, the theoretical AA-2G production was 3.15 g/L and in the vali dation experiments AA-2G production reached 3.13 g/L, which was increased by 14% in comparison with the control （2.76 g/L） by one factor optimization.