空心莲子草多糖的提取研究

Study on the extraction of polysaccharide from Alternanthera philoxeroides

以干燥的空心莲子草粉末为原料,采用水提醇沉法提取空心莲子草水溶性多糖并进行纯化.研究了料水比、浸提温度、滤液浓缩比、醇沉乙醇用量和浸提的时间对多糖收率的影响.最佳条件为:料水比1∶20 g/mL,浸提温度60℃,滤液浓缩比1/5,醇沉乙醇用量2.5倍体积乙醇,浸提时间0.5 h,此条件下粗糖的收率为11.6%,粗糖的纯度为34.2%,多糖的收率为4.0%.对比了活性炭和AB-8大孔树脂吸附法纯化空心莲子草粗糖的效果,AB-8大孔树脂效果最佳.用红外光谱、核磁共振谱和凝胶色谱等对多糖进行了结构表征.

The water-soluble polysaccharide of Alternanthera philoxeroides was extracted and purified by water extraction and alcohol precipitation method with dry Alternanthera philoxeroides powder as raw material.The effects of solid-liquid ratio,extraction temperature,filtrate concentration ratio,ethanol amount,extraction time,and purification conditions on the yield of polysaccharides were studied.The results showed that the solid-liquid ratio was 1∶20 g/mL,the extraction temperature was 60℃,the filtrate concentration ratio was 1/5,the filtrate concentrate was added with 2.5 times the volume of ethanol,and the extraction time was 0.5 h.Under this condition,the yield of crude sugar was 11.6%,the purity of crude sugar was 34.2%,and the yield of polysaccharides was 4.0%.AB-8 macroporous resin is the optimal option to purify the crude sugar of Alternanthera philoxeroides.The composition,structure,and yield of various polysaccharides were analyzed by infrared spectroscopy,nuclear magnetic resonance spectroscopy,and gel chromatography.