酵母发酵鲜党参中多糖的提取及免疫活性研究

Study on the Extraction Process and Immune Activity of Polysaccharides from Fresh Codonopsis Pilosula by Yeast Fermentation

目的优化酵母发酵鲜党参中多糖的提取工艺,并评价其体外免疫活性。方法以酵母发酵鲜党参为原料,通过木瓜蛋白酶辅助提取,乙醇沉淀得到酵母发酵鲜党参中多糖,以提取温度、时间、酶添加量为影响因素,多糖得率为指标,以水提法为对照,进行单因素实验结合响应面设计开展工艺优化,通过高效凝胶渗透色谱法测定多糖的相对分子量,通过MTT法研究多糖对体外脾淋巴细胞和RAW264.7细胞的增殖活性。结果酵母发酵鲜党参中多糖的最佳提取工艺为提取温度63℃,提取时间6 h,酶添加量4%,多糖的提取率17.46%,比水提法(12.69%)提高。且糖醛酸含量提高。酶提法和水提法得到的多糖相对分子量无明显变化。当多糖浓度为0.5,1.0 mg·mL^(−1)时,给予酶提多糖的脾淋巴细胞增殖活力和RAW264.7细胞增殖活力均比水提法增加。结论本研究优选出的酵母发酵鲜党参中多糖的提取工艺切实可行,多糖提取率高且免疫活性显著增强。

OBJECTIVE To optimize the extraction process of polysaccharides in fresh Codonopsis pilosula fermented by yeast and evaluate its immune activity in vitro.METHODS Using yeast-fermented fresh Codonopsis pilosula as raw material,the polysaccharides in yeast-fermented fresh Codonopsis pilosula were obtained by papain-assisted extraction and ethanol precipitation.With extraction temperature,time and enzyme content as the influencing factors,polysaccharide yield as the index,and water extraction as the control,single factor experiment combined with response surface design was carried out to optimize the process.The relative molecular weight of polysaccharides was determined by high performance gel permeation chromatography,and the proliferation activity of polysaccharides on spleen lymphocytes and RAW264.7 cells in vitro was studied by MTT assay.RESULTS The optimal extraction conditions of polysaccharides from fresh Codonopsis pilosula by yeast fermentation were as follows:extraction temperature 63℃,extraction time 6 h,enzyme content 4%.The extraction rate of polysaccharide was 17.46%,which was higher than 12.69%by water extraction.And the uronic acid content increased.The relative molecular weight of polysaccharides obtained by enzyme extraction and water extraction had no obvious change.When the polysaccharide concentration was 0.5,1.0 mg·mL^(−1),the proliferation activity of spleen lymphocytes and RAW264.7 cells treated with enzyme-extracted polysaccharide increased compared with that treated with water extraction.CONCLUSION In this study,the optimized extraction process of polysaccharides from fresh Codonopsis pilosula by yeast fermentation is feasible.The extraction rate of polysaccharides is high and the immune activity is significantly enhanced.