Sugar compositional determination of polysaccharides from Dunaliella salina by modified RP-HPLC method of precolumn derivatization with 1-phenyl-3-methyl-5-pyrazolone

A modified high-performance liquid chromatography method of pre-column derivatization with 1-phenyl-3-methyl-5-pyrazolone (PMP) has been established for high resolution separation and high sensitivity determination of ten monosaccharides simultaneously, which frequently occur in algae polysaccharides. The effects of volume proportion of acetonitrile and pH value of mobile phase (0.1 M phosphate buffer–acetonitrile) on retention and separation of the monosaccharide derivatives were investigated with Eclipse XPB-C18 column screened out. The hydrolyzation condition of polysaccharides and derivatization procedure of hydrolysates were also optimized. The modified analysis method was used for the determination of monosaccharide compositions in five polysaccharide fractions isolated from Duanaliella salina. The results showed that PD1 and PD4a were acidic heteropolysaccharide mainly containing glucose and galactose respectively, and PD4a contained sulfated groups; PD2 and PD3 all were a glucan; while PD4b was a complex of polysaccharide linked with nucleic acids by covalent bonds.