不同采收期乌天麻中多糖的提取及含量测定

Extraction and Content Determination of Polysaccharides from Rhizoma Gastrodiae of Different Harvest Periods

采用水提醇沉法制备天麻多糖,在单因素试验基础上,考察提取时间、提取温度、液固比对天麻多糖提取工艺的影响,通过Box-Behnken法优化天麻多糖的提取工艺参数,确定最佳提取工艺条件为:液固比34∶1(mL/g)、提取温度77℃、提取时间78 min,在此提取条件下,天麻多糖的得率为31.14%。通过对贵州省大方县不同采收期(立冬、冬至、立春)乌天麻中的多糖含量进行测定,结果显示不同采收期乌天麻中多糖的得率差异显著,其中冬至采收的乌天麻中多糖得率最高,最高可达32.2%,但不同采收期乌天麻中的多糖得率均大于20%,表明在这一段时间内采收均能保证天麻质量。

The polysaccharide of Rhizoma Gastrodiae was prepared by hot water extraction and alcohol precipitation method.The extraction conditions were selected by single factor test and optimized by response surface methodology,and the optimum extraction parameters were as follows:the ratio of solvent to material was 34∶1(mL/g),the extraction temperature was 77℃,and the extraction time was 78 min.Under this condition,the extraction rate of polysaccharides from Rhizoma Gastrodiae was 31.14%.The optimized extraction conditions were adopted for polysaccharide content determination from Rhizoma Gastrodiae of different harvest periods.There are significant different among the harvest periods.The Gastrodiae Rhizome polysaccharide content is highest in samples harvested in the winter solstice,reaching to 32.2%.However,the polysaccharide content of Rhizoma Gastrodiae obtained were all greater than 20%,implying a suitable time for Rhizoma Gastrodiae harvest during this period.