Isolation, Purification, and Structural Analysis of Four Functional Saccharides from Chinese Dates

Crude oligosaccharides were obtained from Chinese dates by hot water extraction,decolorized using(201 × 7) 717 type strongly alkaline anion exchange resin,and purified on DEAE-52 cellulose column to obtain three fractions,JuBO1,JuBO2 and JuBO3.JuBO1 was further purified by Sephadex G-25 column chromatography to obtain two single components,JuBO1-1 and JuBO1-2.Besides,JuBO2 and JuBO3 were desalted by Sephadex G-15 column chromatography,along with JuBO1-1 and JuBO1-2,lyophilized and analyzed by HPLC and GC-MS for monosaccharide composition.The monosaccharide composition consisted of arabinose,mannose,galactose and glucose for JuBO1-1,arabinose,rhamnose,fructose,mannose,galactose and glucose for JuBO1-2,arabinose,fructose and glucose for JuBO2 and arabinose,rhamnose,fructose and glucose for JuBO3.The average molecular weights of JuBO1-1,JuBO1-2,JuBO2 and JuBO3 were determined by gel filtration chromatography to be 5952,545,108629 D and 2624 D,respectively.