[Structural features of a neutral heteropolysaccharide CPB-4 from Cynanchum paniculatum].

ABSTRACT

OBJECTIVE: To study the chemical features of CPB-4, a heteropolysaccharide obtained from Cynanchum paniculatum. METHOD: Sugar composition analysis, methylation analysis, partial hydrolysis and carbon-13 nuclear magnetic resonance were used to determine the sugar composition, linkages, main chain, branch chains and branching points. RESULT: CPB-4 is composed of L-arabinose, L-xylose, L-rhamnose and D-galactose in closely molar ratios of 0.80.20.21.0. Its main chain is comprised of 1, 5 linked galactose and side chains are comprised of terminal xylose, terminal arabinose, oligosaccharide of arabinose and oligosaccharide of arabinose, rhamnose and galactose. The branching points are located at C-6 and C-2 of galactose. CONCLUSION: CPB-4 is a new heteropolysaccharide from C. paniculatum.