Water-soluble polysaccharides with pharmaceutical importance from Durian rinds (Durio zibethinus Murr.): isolation, fractionation, characterisation and bioactivity

Crude, pharmaceutically useful water-soluble polysaccharides have been isolated from durian rinds (Durio zibethinus) by hot water extraction followed by ethanol precipitation. The polysaccharides were fractionated by anion exchange chromatography and size exclusion chromatography. Characterisation of the sub-fractions by methanolysis, methylation analysis and NMR spectroscopy revealed that the principal components were pectic polysaccharides with starch as a contaminant. Physical features namely molecular weight (Mw) and intrinsic viscosity of the main fractions were investigated by size exclusion chromatography coupled to multi angle laser light scattering (SEC/MALLS) and capillary viscometer, respectively. The main fractions were subjected to the complement-fixation assay and the relationship of the chemical features of the polysaccharide fractions with their activity was also considered.