Optimization of Extraction Process for Polysaccharides from Kalimeris indica L. by Response Surface Methodology and Polysaccharide Contents in Different Parts

Polysaccharide extraction from the aboveground parts of Kalimeris indica L.wildly grown in the Huaguoshan Mountain Area of Lianyungan was studied.One-factor-at-a-time method was used to identify extraction parameters such as material-to-liquid ratio,time and temperature as main factors that influence the extraction yield of polysaccharides.A 3-factor,3-level central composite design involving the three independent variables(extraction parameters) followed by response surface analysis was carried out to optimize the extraction parameters.The optimal extraction conditions were twice repeated extractions at 98 ℃ and a material-to-liquid ratio of 33:1(mL/g) for 3.5 h each time.Under these conditions,the predicted and experimental extraction yields of polysaccharides were 4.2037% and 4.1946%,respectively.The results of determination of polysaccharide content showed that significant differences in polysaccharide content existed among different parts of the plant: the highest polysaccharide content,4.9407%,was observed in the leaves followed by the stems,1.5356%,and the roots exhibited the lowest polysaccharide content,only 0.6817%.