金线莲多糖的提取优化与纯化

Optimization and purification of extraction of polysaccharides from Anoectochilus roxburghii

目的以响应面法优化超声提取金线莲多糖的工艺,同时,对多糖纯化中除蛋白方法进行考察。方法以多糖提取率为检测指标,在单因素考察的基础上采用Box-Behnken实验设计及响应面法对料液比、超声时间、超声提取温度3个因素进行优化;以多糖保留率和蛋白脱除率对Sevage试剂法、TCA法、盐法(NaOH-CaCl2法和NaOH-NaCl法)、盐酸法5种脱蛋白方法进行考察。结果金线莲多糖最佳提取工艺为:料液比1∶10,超声提取温度48℃,超声提取时间36 min,超声提取次数2次,超声功率为300 W,该条件下金线莲多糖提取率达到了13.13%;同时以NaOH-CaCl2法脱蛋白,多糖损失率为18.74%,蛋白脱除率为95.62%。结论超声提取操作简单,优化后提取方法能够取得较高提取率,NaOH-CaCl2法脱蛋白能够获得较高蛋白脱除率及多糖保留率,该方法适用于金线莲多糖活性成分的开发研究。

Objective To optimize the process of ultrasonic extraction of polysaccharide in Anoectochilus roxburghii and to investigate the method of protein removal. Methods The extraction rate of polysaccharide was used as the detection index. On the basis of single factor investigation, Box-Behnken experimental design and response surface method were used to optimize the three factors of material-liquid ratio, ultrasonic time and ultrasonic extraction temperature. The five deproteinization methods including Sevage reagent method, TCA method, salt method(NaOH-CaCl2 and NaOH-NaCl) and hydrochloric acid method were investigated with the retention rate of polysaccharide and protein removal rate. Results The optimal extraction conditions of polysaccharide from Anoectochilus roxburghii were as follows: liquid-to-solid ratio was 10∶1, extraction temperature was 48 ℃and extraction time was 36 min with extraction 2 times, ultrasonic power was 300 W, the extraction rate was 13.13%. NaOH-CaCl2 deproteinized methods∶ the loss rate of polysaccharide was 18.74%, and the removal rate of protein was 95.62%. Conclusion Ultrasonic extraction is easy to operate, and the optimized extraction method can achieve a high extraction rate. NaOH-CaCl2 deproteinization methods can get high protein removal rate and polysaccharide retention rate. This method is suitable for the research and development of the active components of the polysaccharides from Anoectochilus roxburghii.