浓硫酸法制备魔芋葡甘聚糖硫酸酯(KGMS)

Preparation of sulphated konjac glucomannan(KGMS) by sulfuric acid method

以魔芋葡甘聚糖(KGM)为研究对象,采用浓硫酸法制备魔芋葡甘聚糖硫酸酯(KGMS)。控制浓硫酸与正丁醇总体积为10mL,并在单因素实验的基础上,选择浓硫酸与正丁醇体积比、反应时间和KGM质量为自变量,KGMS取代度为响应值,利用Box-Benhnken中心组合设计原理和响应面分析法,研究各自变量及其交互作用对取代度的影响,模拟得到回归方程的预测模型。确定最佳制备工艺为:浓硫酸与正丁醇体积比为3.22∶1、反应时间为33min、KGM质量为0.59g。在此条件下制备的KGMS的平均取代度为0.93。通过红外光谱分析表明,经过酯化后KGM在1257cm-1和814cm-1处形成新的吸收峰,为S=O和C-O-S键的特征吸收峰,说明KGM硫酸酯化成功,制备获得的产物为KGMS。

Sulphated konjac glucomannan（KGMS） was prepared by using sulfuric acid method. Controled the total volume of concentrated sulphuric acid and 1 -butanol that were 10mL. Then three reaction parameters including the volume ratio of concentrated sulphuric acid and 1 -butanol,reaction time and quantity of KGM were optimized by using central composite design and response surface methodology based on single factor investigations for achieving maximum degree of substitution （DS） of KGMS. The interaction of the respective variables and their influences on the DS of KGMS were studied by using Box -Benhnken central composite design and response surface analysis theory,and the simulated quadratic polynomial regression equation of prediction model was set up. Under the optimal condition of concentrated sulphuric acid and 1-butanol volume ratio of 3.22∶1,reaction time of 33min,KGM quantity of 0.59g,the average DS of KGMS was 0.93. FTIR analysis result showed KGMS formed two new absorption peak at 1257cm -1 and 814cm -1 ,which were the characteristic peak of S=O and C-O-S groups,indicating the successful preparation of KGMS.