Polyamide-based Purification Of Polysaccharides From Selenium-enriched Potato And Its Physical And Chemical Properties

In this paper,the crude polysaccharide was obtained by water extraction and alcohol precipitation,and the extraction conditions were optimized.As the best extraction condition,the ratio of material to liquid was 1:20,the extraction time was2 hours and the frequency was third,and the yield of crude polysaccharide was 6.9%.The polyamide was used to deproteinize the polysaccharide solution,it was determined that when the raw ratio of polyamide was 50:1,the stirring time was 6 h,the highest protein removal rate could reach 78.5%.The water-soluble polysaccharides was separated and purified by the joint use of DEAE-52 resin and graded alcohol precipitation.The crude polysaccharides was eluted by distilled water and salt solution from DEAE-52 resin to separate neutral polysaccharide WPS and acid polysaccharides SPS.By graded alcohol precipitation of WPS?SPS,seven kinds of polysaccharide components—SPS-1,SPS-2,SPS-3,SPS-4,WPS-1,WPS-2,WPS-3 were obtained.Physical and chemical analysis and activity research on seven kinds of polysaccharides revealed that the larger the molecular weight,the lower the solubility of polysaccharides.Polysaccharides with different components have different activities,which are related to the polysaccharide triple helix structure.The two polysaccharide SPS-3,WPS-2 had higher activity.SPS-1?SPS-3?SPS-4 have triple helix structures.SPS-3 and WPS-2 which shows better oxidation activity were selected for measurements of monosaccharide composition,molecular weight determination,IR,Raman,and NMR analysis.The results show that SPS-3 is an acidic Se-polysaccharide with ?-configuration glycosidic bonds composed of eight monosaccharides.The molecular weight of the polysaccharide is 49080,of which the highest monosaccharide content is xylose,reached 22.28%,followed by fucose and glucose.WPS-2 is a neutral Se-polysaccharide with ?-configuration glycosidic bonds composed of eight monosaccharides,with a molecular weight of 46365,of which the highest monosaccharide content is glucose,which is 33.95% followed by galactoseand arabinose.