生地黄中低聚糖的提取和纯化研究

Preparation and purification of oligosaccharide from Radix Rehmanniae

目的研究从生地黄中提取分离低聚糖的工艺。方法以水苏糖的量为指标,采用正交试验优化水提取工艺,考察了除杂工艺中大孔树脂种类、洗脱液用量及活性炭脱色方法,并采用葡聚糖凝胶柱纯化得到生地黄低聚糖。结果优选的水提取工艺为:12倍量水,煎煮3次,每次0.5 h。水提取液经D-101大孔吸附树脂除杂,0.1%活性炭脱色3次,SephadexG15葡聚糖凝胶分离纯化获得生地黄低聚糖部位,其中水苏糖质量分数大于60%。结论该工艺从生地黄中提取分离低聚糖部位,工艺合理、可行,低聚糖部位收率达药材量的26%。

Objective To optimize the technique of isolating and extracting oligosaccharide from Radix Rehmanniae. Methods The optimum conditions for the water extracting technique of Radix Rehmanniae were studied by orthogonal test design. Then the water extract was isolated by macroporous resins and active charcoal successively, meanwhile the pattern of macroporous resins, the volume of the eluents, and the decolorizing methods of active charcoal were studied. And then the oligosaccharide was obtained after being purified by Sephadex gel column chromatography. The content of stachyose was determined by HPLC. Results The optimal preparation process was as follows. 12 fold water, three times, 0.5 h for each time. Then the water extract was isolated and purified by D-101 macroporous resins, 0.1% active charcoal and Sephadex G15 column chromatography were successively used to obtain the oligosaccharide. The analysis of oligosaccharide indicated its main constituents are stachyose, rafinose, and manninotriose, and the content of stachyose is more than 60%. Conclusion This preparation technique of extracting oligosaccharide from Radix Rehmanniae is reasonable and feasible. And the yield of the oligosaccharide from Radix Rehmanniae achieves to 26 %.