基于分步醇沉法研究酒制黄精多糖理化性质及免疫活性

Study on Physicochemical Properties and Immune Activity of Polysaccharides from Wine-Processed Huangjing(Polygonati Rhizoma)Based on Step Alcohol Precipitation

目的对酒制黄精水溶性多糖(Polysaccharides from wine-processed Polygonatum sibiricum.,PSPW)进行分步醇沉,对各醇沉组分理化性质及免疫活性进行研究。方法采用分步醇沉法对PSPW进行分离、纯化;采用气相色谱(GC)、高效凝胶渗透色谱(HPGPC)及傅里叶变换红外光谱(FT-IR)等方法对各醇沉组分的理化性质进行研究;采用MTT法、中性红吞噬实验及Griess法评价各醇沉组分对RAW 264.7细胞免疫活性的影响。结果随分步醇沉中所用乙醇浓度增加,依次获得0~30%、30%~50%、50%~70%及70%~80%多糖组分,分别命名为PSPW-1、PSPW-2、PSPW-3及PSPW-4;理化性质结果表明4个醇沉组分(分子量分别为2.26×10^(4)、2.24×10^(4)、1.15×10^(4)及6.58×10^(3)u)均为糖蛋白复合物;各醇沉组分单糖组成种类和比例存在显著差异,均含高比例的半乳糖;免疫活性研究表明各组分均可促进RAW264.7细胞活力、吞噬中性红能力、分泌NO能力及分泌酸性磷酸酶活力,其中组分PSPW-3免疫活性最强。结论分步醇沉法所得PSPW各醇沉组分理化性质和免疫活性存在较大差异,推测PSPW-3为酒制黄精多糖发挥免疫调节作用的最佳活性组分,本研究为酒制黄精多糖最佳免疫调节活性组分的构效关系及黄精多糖功能性食品开发提供依据。

Objective Isolation and purification of water-soluble polysaccharide from wine-processed Huangjing(Polygonati Rhizoma)(PSPW)was carried out by step alcohol precipitation,and the physicochemical properties and immune activity of each alcohol precipitation component were studied.Methods The step alcohol precipitation method was used to isolate and purify PSPW and the physicochemical properties of each alcohol precipitation component were analyzed by gas chromatography(GC),high performance gel permeation chromatography(HPGPC)and Fourier transform infrared spectroscopy(FT-IR).MTT method,neutral red phagocytosis test and Griess method were used to evaluate the effect of each alcohol precipitation component on the immune activity of RAW 264.7 cells.Results The alcohol precipitation fractions(0~30%,30%~50%,50%~70%and 70%~80%)were obtained with the increasing ethanol concentration,which were named as PSPW-1,PSPW-2,PSPW-3 and PSPW-4.The results of physicochemical properties showed that the four alcohol-precipitated components(with molecular weights of 2.26×10^(4),2.24×10^(4),1.15×10^(4)and 6.58×10^(3)u)were all glycoprotein complexes.There were significant differences in the types and proportions of monosaccharide composition of each fractions,all of which contained a high proportion of galactose.The immune activity study showed that each component could promote RAW 264.7 cell viability,phagocytosis of neutral red,NO secretion and acid phosphatase activity,among which component PSPW-3 had the strongest immune activity.Conclusion There were great differences in the physicochemical properties and immune activity of the alcohol-precipitated components from PSPW obtained by the step alcohol precipitation method.It was speculated that the component PSPW-3 was the best active component of PSPW to exert the immunomodulatory effect.This study provided a basis for the study of the structure and structure-activity relationship of optimal immunomodulatory active components in PSPW.