Abstract: The extraction technology of the water-soluble polysaccharide from Potentilla anserina was studied in this paper.The influences of liquid-solid ratio (V/W),extraction time and temperature on the extraction yield were investigated.On the basis of single factor tests,a Box-Behnken design (BBD) was used to study the influence of the 3 independent variables on the extraction yield.The results showed that the optimal extraction parameters were as follows:the liqud-solid ratio was 20.25:1, extraction time was 4.37 h and extraction temperature was 82 ℃.The extraction yield of polysaccharide was 24.53±0.24%.

Key words: Potentilla anserine, polysaccharide, extraction, response surface, optimization