Novel branch patterns and anticoagulant activity of glycosaminoglycan from sea cucumber Apostichopus japonicus

A novel glucosidic pattern of fucose branches was found in the glycosaminoglycan from the sea cucumber Apostichopus japonicus in China. The methylation of desulfated/carboxyl-reduced polysaccharides and analysis of unsaturated disaccharides generated from the enzymolysis of the defucosed polysaccharides demonstrated that the branch is formed by one fucopyranosyl residue, 46.5% of which is linked through the O-3 position of beta-n-giucuronic acid, while 8.7% and 43.9% are linked through the 0-6 and 04 positions of the N-acetylgalactosamine moiety. The beta-o-glucuronic acid, N-acetyl-beta-D-galactosamine, alpha-L-fucose and sulfate ester with the molecular ratio of 0.97:1.00:1.13:3.85 composed the backbone -> 4)GlcUA13(1 -> 3)Ga1NAc13(1 -> and sulfated fucose branches. The sulfation patterns of fucose branches and the linkage pattern of the backbone structure were determined by 1/2 dimension NMR. The most abundant branch species were 2,4-di-O-sulfated and 3,4-di-O-sulfated fucose, but 4-mono-O-sulfated residue was also present. The structure of presently obtained glycosaminoglycan is different from that previously obtained from Stichopus japonicus (Kariya etal., Carbohyd. Res. 297 (1997) 273-279), which suggests that the structures of glycosaminoglycans from the same species of different regions somehow differ. The anticoagulant assay indicated that the polysaccharide possessed a high anticoagulant activity and the sulfated fucose branches were essential to the activity. (C) 2014 Elsevier B.V. All rights reserved.