中文摘要：

采用水提、醇沉法从大粒车前子中提取得到多糖提取物,然后经Sevag法脱蛋白、SephacrylTM S-400HR葡聚糖凝胶柱层析分离纯化,得到PLCP-1、PLCP-2和PLCP-3三个组分。应用高效凝胶渗透色谱法等方法测定PLCP-2组分纯度及其理化性质;进一步采用单因素试验结合二次响应面法对车前子多糖提取工艺进行优化。结果表明：PLCP-2为均一多糖（PLP）,测得其相对分子质量为1849268、糖含量87.3%、蛋白含量1.2%、糖醛酸含量14.7%;通过岭脊分析获得最佳提取工艺条件,结合实际操作将最佳条件修正为提取温度99℃、料液比1：30（g/mL）、提取时间5.45h,实际测得多糖得率为13.79%,与理论预测值比较接近。该工艺经济、简约、可行性强。

英文摘要：

Polysaccharides were isolated from seeds of Plantago asiatica L. by water extraction and ethanol precipitation, and then subjected to protein removal by Sevag method and purification using gel permeation chromatography on SephacrylTM S400HR column. Extraction conditions were optimized by orthogonal design and response surface methodology on the basis of extraction rate of polysaccharides. Three fractions were obtained and named as PLCP-1, PLCP-2 and PLCP-3. Results showed that PLCP-2 （also named as PLP） was a kind of homogeneous polysaccharides with molecular weight of 1849268 Da determined by high performance gel permeation chromatography. The contents of polysaccharides and protein were 87.32% and 1.16%, respectively; while the content of uronic acid was 14.66%. The optimal extraction conditions were extraction temperature of 99 ℃, material-liquid ratio of 1：30 （g/mL） and extraction time of 5.45 h. Under these optimal extraction conditions, the extraction rate of polysaccharides from Plantago asiatica L. was 13.79%, which was in agreement with the predicted value. This optimal extraction conditions are economic, simple and feasible, and also provide a theoretical reference for industrial preparation of polysaccharides from seeds of Plantago asiatica L..