Box-Behnken响应面法优化酶法制备α-环糊精及其分离纯化

Optimization of Enzymatic Preparation ofα-Cyclodextrin by Response Surface Methodology and Its Separation and Purification

以α-环糊精葡萄糖基转移酶(α-cyclodextrin glycosyltransferase,α-CGTase)为催化剂,研究其作用于马铃薯淀粉产出α-环糊精的酶法生产工艺。通过单因素试验和Box-Behnken中心组合设计法设计响应面试验,分析不同条件对α-环糊精转化率的影响。试验结果表明,当α-CGTase的反应温度为50℃,pH值为5.5时,α-CGTase呈现最好的酶活性质,α-环糊精的转化率最高。反应体系中加入有机溶剂正癸醇,底物浓度为1.0%,加酶量为200 U/g淀粉,反应时间为14 h时,α-环糊精的转化率可达40.6%。通过水蒸气蒸馏法进一步分离纯化α-环糊精产物,经高效液相色谱法(high performance liquid chromatography,HPLC)鉴定分析,转化率可达到20%~40%,纯度达到75%。

Usingα-cyclodextrin glycosyltransferase(α-CGTase)as a catalyst,the enzymatic production process of potato starch to produceα-cyclodextrin was studied.The response surface test was designed by single factor test and box-behnken center combination design method to analyze the influence of different conditions on theα-cyclodextrin conversion rate.The experimental results showed that when the reaction temperature ofα-CGTase was 50℃and the pH value was 5.5,α-CGTase exhibited the best enzyme activity,and the conversion rate ofα-cyclodextrin was the highest.In the reaction system,the organic solvent n-decanol was added,the substrate concentration was 1.0%,the enzyme amount was 200 U/g starch,and the reaction time was 14 h.The conversion rate ofα-cyclodextrin could reach 40.6%.Theα-cyclodextrin product was further separated and purified by steam distillation.After identification and analysis by high performance liquid chromatography(HPLC),the conversion rate could reach 20%-40%and the purity could reach 75%.