RESUMO
Objective To optimize the technological conditions of polysaccharide purification from compound Qianyu water decoction. Methods Water extraction and alcohol precipitation, resolution, Sevag method and dialysis method were used to purify polysaccharide.The purity of polysaccharide was measured with the phenol-sulfuric acid spectrophotometry.On the basis of single factor test, effects of redissolved solid-liquid ratio, number of protein removal, and dialytic time on polysaccharide purity of Qianyu were investigated by orthogonal test. Results The best conditions for purification of polysaccharide in Qianyu were as follows: liquid-solid ratio was 1:40(g/mL, W/V), remove protein for 10 times, and dialysis for 18 h.The content of polysaccharide could reach 69.04%, and the transfer rate was 51.84%. Conclusion The optimized purification process was simple and accurate.It can be used for polysaccharide purification in compound Qianyu water decoction.