桑黄子实体两种新多糖的分离纯化与结构研究

Purification and Characterization of Two New Polysaccharides from Fruiting Body of Phellinus linteus

目的从桑黄子实体中分离具有抗肿瘤活性的多糖成分,并进行结构分析。方法热水浸提法提取桑黄子实体中的粗多糖,经醇沉、冷冻干燥、离子交换层析、凝胶层析和超滤,得到纯度较高的多糖,通过HPLC、IR、1H-NMR、13C-NMR、高碘酸氧化及Smith降解确定2种多糖的相对分子质量、组成及结构。结果分离纯化得到相对分子质量分别为14.2×103,22.2×103的多糖PL-A及蛋白聚糖PL-B,两者都是结构复杂的中性杂多糖。PL-B中,糖占71%,蛋白质占7%;PL-A,PL-B均含大量葡萄糖及少量甘露糖,PL-B中还有部分鼠李糖;PL-B所含氨基酸包括缬氨酸、赖氨酸、天冬氨酸、甘氨酸。结论多糖PL-A与蛋白聚糖PL-B为首次从桑黄子实体中提取到的多糖成分。

Objective To separate and purify the anti-tumor polysaccharides from the fruiting body of Phellinus linteus, then study the chemical structures of the parts. Methods The crude polysaccharides from the fruiting body of PheUinus linteus were extracted in hot water, then precipitated with ethanol. From the crude extract, the polysaccharides were separated and purified using the methods of freeze drying, ultra filtration, ion exchange and gel chromatography. The relative molecular mass, composition and structure were studied by HPLC, IR, ^1H-NMR, ^13C- NMR, periodate oxidation and Smith degradation. Results Polysaccharide PL-A and proteoglycan PL-B were obtained. Both PL-A and PL-B were complex neutral heteropolysaccharides. The relative molecular mass of PL-A was 1.42× 10^4 and that of PL-B was 2.22× 10^4. The proteoglycan PL-B consisted of 71% polysaccharide and 7% protein. The saccharide chains of PL-A and PL-B were both composed of most glucose and little mannose, and some rhamnose existed in PL-B besides. The amino acid pattern showed that PL-B contained valine, lysine, aspartic acid, and glycine. Conclusion Polysaccharide PL-A and proteoglycan PL-B can be obtained from the fruiting body of Phellinus linteus for the first time.