NMR characterization for polysaccharide moiety of a glycopeptide

Ganoderma lucidum is a traditional medicinal herb used to treat various diseases in China and Southeast Asia for thousands of years. An aqueous glycopeptide, LZ-B-1, was prepared by successive chromatography and exhibited an immunostimulating potential. To better understand the mechanism of bioactivity for this compound, the polysaccharide moiety of glycopeptide LZ-B-1 was studied by NMR spectroscopy. The results indicated that the polysaccharide moiety had a backbone of 1,6-disubstituted-α-galactopyranosyl, 1,2,6-trisubstituted-α-galactopyranosyl, 1,3-disubstituted-β-glucopyranosyl and 1,4,6-trisubstituted-β-glucopyranosyl residues. The branches were mainly composed of 1-substituted-β-glucopyranosyl and 1-substituted-α-fucopyranosyl residues.