【摘要】 采用乙醇研磨法和水溶醇沉法制备魔芋葡甘聚糖,研究了两种方法对魔芋葡甘聚糖纯度、表观黏度、黏均分子量及溶解性能的影响,结果表明,水溶醇沉法制备的魔芋葡甘聚糖,其纯度、表观黏度、黏均分子量与乙醇研磨法基本相同,但溶解速率差异显著,从26.4mg/mL.h下降到10mg/mL.h。用红外光谱,X射线衍射,扫描电镜等方法表征了魔芋葡甘聚糖的结构,结果表明,乙醇研磨法对葡甘聚糖形态及微观结构几乎没有影响,能保留魔芋葡甘聚糖固有的性能,而水溶乙醇沉淀法由于使其分子链发生伸展、重排、卷曲、相互缠绕交织等,其表面形态和聚集态结构发生了变化,从而魔芋葡甘聚糖的溶解速率明显降低。更多还原

【Abstract】 The preparation of konjac glucomannan(KGM) using water-extracting alcohol-precipitating and milling KGM in 50% ethanol was investigated.The results show that the purity,apparent viscosity,weight average molecular weight of KGM,which is obtained using two methods,are similar.The KGM dissolution rates are significant different got from different methods.KGM dissolution rates obtained using milling KGM in ethanol are 26.4 mg/mL·h,and KGM dissolution rates obtained using water-extracting alcohol-precipitating method are 10 mg/mL·h.The KGM structure was characterized using FT-IR,X-ray diffraction and SEM.The results of IR spectrum,X-ray diffraction and SEM microphotographs show that expanding,rearrangement,crimping,interlacing and interaction between the molecular chains have happened in molecular of KGM obtained using water-extracting alcohol-precipitating method.In this process,KGM molecular chains expended in aqueous solution,and crimped when precipitated from ethanol.This preparation method resulted in significant changes of dissolution rate.更多还原