Isolation, purification and structural elucidation of polysaccharide from the fruiting bodies of Phellinus baumii Pilát

Objective: To study the isolation, purification and structural elucidation of the polysaccharides from the fruiting bodies of Phellinus baumii Pilat. Methods: The process of isolating and purifying a water soluble polysaccharide PBF6 was achieved by hot water extraction, ethanol precipitation and freeze-drying. The water soluble polysaccharide was separated by chromatography on a DEAE-Sepharose Fast Flow column and Sephacryl S-400 High Resolution column. The structural of polysaccharide was elucidated by UV, IR, GC, GC-MS and NMR. Results: The molecular weight of PBF6 was 3.23×105 u. Sugar analysis showed this polysaccharide was composed of glucose only. Methylation analysis revealed 1,6-linked Glcp and 1,3-linked Glcp in a molar ratio of 1.0:2.0. NMR analysis further showed that the structure consist mainly of a backbone of (1,3)-linked-D-glucopyranosyl residues and (1,6)-linked-D-glucopyranosyl residues with the following structure: →3)-β-D-Glcp-(1→3)-β-D-Glcp-(1→6)-β-D-Glcp-(1→. Conclusion: PBF6 was a glucan. The established method can be used to purify and structure analysis of the polysaccharides.