Purification, structural characterization and anticoagulant activities of four sulfated polysaccharides from sea...

Sulfated polysaccharides from sea cucumber possess unique chemical structure and various biological activities. In this study, four sulfated polysaccharides were purified from the body wall of Holothuria fuscopunctata by anion exchange chromatography and chemical depolymerization. They were identified as sulfated fucan (SFI, SFII), fucosylated chondroitin sulfate (FCS) and sulfated aminoglycan (AG) by physicochemical and structural analyses. The Mw of SFI, SFII, FCS and AG were 470.6, 36.8, 42.6, 39.6 kDa and the sulfate content was 21.40%, 35.86%, 33.70%, 35.70%, respectively. Their primary structures were clarified both by monosaccharide composition and 1D/2D NMR spectroscopy analysis. As a result, the repeating sequences of FCS and SFII were →4)-[L-Fuc_3S4S-(α1 → 3)]-D-GlcA-(β1 → 3)-D-GalNAc_4S6S-(β1 → and →4-L-Fuc-(3SO₃-)-α1→, respectively. The primary structure of SFI was →3)-L-Fuc_2S4S-(α1 → 4)-L-Fuc-(α1 → 3)-L-Fuc_2S-(α1 → 4)-L-Fuc-(α1→. The sulfated AG was composed of four types of monosaccharides. Their anticoagulant activities were further evaluated in vitro. FCS and AG showed potent anticoagulant activity and intrinsic factor Xase inhibition activity. These results expand the knowledge on the structure types of sulfated polysaccharides from sea cucumber and further illustration of their functionality.