选用蔗糖磷酸化酶和葡聚糖磷酸化酶合成直链糊精，并对工艺条件进行优化。以蔗糖为底物，在添加磷酸盐的条件下，蔗糖磷酸化酶催化反应，生成中间产物葡萄糖-1-磷酸，选用液质联用仪鉴定葡萄糖-1-磷酸的产生；加入麦芽四糖作引物，葡聚糖磷酸化酶催化合成直链糊精，用高效离子交换色谱分析终产物直链糊精的聚合度分布。通过单因素实验，分别研究酶浓度、反应时间、pH及温度对两步反应的影响。蔗糖磷酸化酶催化生成中间产物葡萄糖-1-磷酸的优化工艺条件为：酶浓度4．0U／mL、反应时间4h、pH6．5、温度40℃；葡聚糖磷酸化酶催化合成直链糊精的优化工艺条件为：酶浓度5．0U／mL、反应时间4h、pH4．5、温度40℃。%Sucrose phosphorylase and glucan phosphorylase were chosen to synthesize the amylodextrin and the process conditions were optimized in this paper. Using sucrose as substrate and phosphate as buffer, the reaction was catalyzed by sucrose phosphorylase to produce the intermediate product glucose-l-phosphate which was determined by liquid chromatography-mass spectrometry. Based on the above system, the synthetic reaction using mahotetraose as primer was catalyzed by glucan phosphorylase to produce amylodextrin. The degree of polymerization of the product contained in the system was determined by high-performance anion-exchange chromatography. The optimal conditions including enzyme concentration, time, pH and temperature were determined by mono-factor experiment. The results indicated that the optimum conditions of the reaction which using sucrose phosphorylase as catalyst to produce glucose- 1-phosphate were as follows: enzyme concentration 4.0 U/mL, reaction time 4 h, pH 6.5, temperature 40℃ ; and conditions of reaction which using glucan phosphorylase as catalyst to synthesis amylodextrin were as follows: enzyme concentration 5.0 U/mL, reaction time 4 h, pH 4.5, temperature 40℃.
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