Monosaccharide composition of sweetpotato fiber and cell wall polysaccharides from sweetpotato, cassava, and potato analyzed by the high-performance anion exchange chromatography with pulsed amperometric detection method

The cell wall materials (CWMs) from sweetpotato (Ipomoea batatas cv. Kokei 14), cassava (Manihot esculenta), and potato (Solanum tuberosum cv. Danshak u) and commercial sweetpotato fiber as well as their polysaccharide fractio ns were analyzed for sugar composition by the high-performance anion exchan ge chromatography with pulsed amperometric detection (HPAEC-PAD) method. Th e separation of arabinose and rhamnose, and xylose and mannose, by this met hod has been improved using a CarboPac PA 10 column. Pretreatment of the CW Ms and cellulose fractions with 12 M H2SO4 was required for complete hydrol ysis to occur. Commercial sweetpotato fiber was found to be mainly composed of glucose (88.4%), but small amounts of other sugars were also detected. Among the root crops, sweetpotato CWM had the highest amount of pectin and galacturonic acid. Fucose was detected only in cassava CWM and its hemicell ulose fraction, while galactose was present in the highest amount in potato CWM. Among the polysaccharide fractions, it was only in the hemicellulose fraction where significant differences in the sugar composition, especially in the galactose content, were observed among the root crops.