不同灵芝菌株子实体多糖的特征分析及免疫活性评价

Characterization and Immunostimulatory Activity of Polysaccharides from Fruiting Bodies of Different Ganoderma lucidum Strains

采用高效分子排阻色谱-多角度激光光散射-示差折光检测器联用法对不同灵芝菌株的110个(Ganoderma lucidum)子实体样品的多糖重均分子量分布进行分析,依据出峰时间和出峰数量,可将这些样品分为4组:A组有7个样品,其子实体多糖含3个组分GLP 1、GLP 2、GLP 3;B组有77个样品,其子实体多糖含1个组分GLP 3;C组有24个样品,其子实体多糖含2个组分GLP 1、GLP 3;D组有2个样品,其子实体多糖含2个组分GLP2和GLP3。GLP1、GLP2的重均分子量分别为1.85×10^(6)~5.47×10^(6)、2.16×10^(6)~5.73×10^(6) g·mol,GLP3的重均分子量约为10^(4) g·mol^(-1)。用乙醇分步沉淀法对8个代表性灵芝子实体的高分子量多糖组分(重均分子量>10^(6) g·mol^(-1))进行分离,得到纯度较高的GLP1(多糖含量80.47%~92.52%)和GLP2(多糖含量69.75%~91.71%),并对其重均分子量、单糖组成、糖苷键连接方式以及免疫活性进行比较,结果表明:GLP1和GLP2为结构不同的葡聚糖,其中GLP1是以β-(1→3)-连接为主链、以β-(1→6)-连接为支链的葡聚糖,而GLP2组分是以α-(1→4)-连接为主链、α-(1→6)-连接为支链的葡聚糖;GLP1组分与Dectin-1受体结合激活免疫的活性优于GLP 2组分。研究结果表明,针对灵芝免疫产品开发时,应更加关注灵芝子实体中高分子量多糖GLP1组分的分布和含量。

Using high performance size exclusion chromatography (HPSEC) in combination with multi-angle laser light scattering detector and refraction index detector,polysaccharides from 110 fruiting body samples of different Ganoderma lucidum strains were analyzed for molecular weight distribution.Based on time and number of elution peaks,the 110 samples were categorized into the following four groups.Group A contained seven samples comprising three polysaccharide fractions GLP 1,GLP 2 and GLP 3.Group B had 77 samples and their fruiting body polysaccharides only contained GLP 3.Group C had 24 samples and their fruiting body polysaccharides comprised GLP 1 and GLP 3.Group D had two samples and their fruiting body polysaccharides comprised GLP 2 and GLP 3.The Mof GLP 1,GLP 2 and GLP 3 were 1.85×10^(6)-5.47×10^(6) g·mol,2.16×10^(6)-5.73×10^(6) g·mol,and 10^(4) g·mol^(-1),respectively.Then high purity GLP1 (80.47%-92.52%polysaccharide content) and GLP 2 (69.75%-91.71%polysaccharide content) were obtained from eight representative G.lucidum fruiting body samples by gradient ethanol precipitation.The obtained GLP1 and GLP2 were compared in terms of M,monosaccharide composition,glycosidic linkage mode and immunological activity.The results showed that GLP 1 and GLP 2 were glucans comprising different structures.GLP 1 was a glucan comprising aβ-(1→3)-linked backbone andβ-(1→6)-linked side chains,whereas GLP 2 was a glucan comprising anα-(1→4)-linked backbone andα-(1→6)-linked side chains.GLP1 showed stronger Dectin-1 binding activity to stimulate immunity than GLP 2.The results suggested that the distribution and content of GLP 1 from G.lucidum should receive more attention when developing immune products.