Pectins from Canna edulis Ker residue and their physicochemical characterization

Water-soluble pectin (WSP), chelated-soluble pectin (CSP) and acid-soluble pectin (ASP) were sequentially extracted from Canna edulis Ker residue, a by-product after the extraction of starch, and their physicochemical properties were studied. ASP was further separated through preparative column chromatography, leading to isolation of two fractions, ASPI and ASPII, which chemical features were analyzed by GC, GC–MS and NMR. Moreover, their behaviors in the simulated gastric and intestinal fluid were monitored. The results exhibit that C. edulis residue contains high amount of ASP derived from the heteropolysaccharide with rhamnogalacturonan as main chain. Furthermore, three pectins show gel formation and dissolution behaviors. It well suggests that C. edulis residue can be exploited for a good source of pectin for functional materials.