Structural elucidation of a 3-O-methyl-D-galactose-containing neutral polysaccharide from the fruiting bodies of Phellinus igniarius

摘要

PIP60-1,a novel heteropolysaccharide isolated from fruiting bodies of the medicinal fungus,Phellinus igniarius,has a molecular weight of 1.71 x 10~4Da and is composed of L-fucose,D-glucose,D-mannose,D-galactose and 3-O-Me-D-galactose in a ratio of 1:1:1:2:1.A structural investigation of PIP60-1 carried out using sugar and methylation analyses,combined with 1H and 13C NMR spectroscopy,including COSY,TOCSY,NOESY,HSQC and HMBC experiments,established the repeating unit of the polysaccharide as the following.