ISOLATION, PURIFICATION AND STRUCTURAL CHARACTERISTICS OF GLYCOSAMINOGLYCANS FROM SEA CUCUMBER STICHOPUS HORRENS

Abstract

Sea cucumber glycosaminoglycans have been well known as potential anticoagulant and antithrombin agents. In this investigation, glycosaminoglycans were isolated from sea cucumber Stichopus horrens by papain enzymatic digestion. Crude glycosaminoglycans were fractionated and purified by using anion-exchange chromatography on the DEAE-Macro Prep column to give two fractions of fucosylated chondroitin sulfate (FCS1) and fucan sulfate (FS2). Structural characteristics of F1 and F2 fractions were elucidated using chemical and IR, NMR spectroscopic methods. The results showed that the monosaccharide compositions of FCS1 consist of N-Acetyl-Galactosamine (GlcNAc), D-Glucuronic acid (GlcA) and Fucose (Fuc) residues with different molar ratios, while FS2 content only fucose residues. Sulfate contents of FCS1 and FS2 were 47.4% and 48.1%, respectively. FCS1 and FS2 fractions were different in the pattern of sulfation of N-Acetyl-Galactosamine and fucose residues. IR and NMR spectra of two frations showed that sulfate groups were primarily occupied at C4 of pyranose residues in FS2 and C6, C2 and/or C3 of pyranose residues in FCS1 fraction. Our results contributed to knowledge on structural types of glycosaminoglycan from sea cucumbers in Vietnam. The establishment of structural features plays an important role in further studies of the structure-bioactivity relationship of sea cucumber glycosaminoglycan.