In this study, we isolated two fucosylated polysaccharide sulfates (ACP and HOP) from sea cucumber Acaudina molpadioidea and Holothuria nobilis, with an average molecular weight of 90.8 and 135.8 kDa, respectively. We investigated and compared their anticoagulant activities through anticoagulant assay. Our data showed that both polysaccharides possessed good anticoagulant activity, but HOP's activity was higher than that of ACP. Due to the different anticoagulant activities of ACP and HOP, we compared the preliminary structural characterizations of these two sulfated polysaccharides, and found that both ACP and HOP consisted of beta-D-glucuronic acid, beta-D-N-acetyl-galactosamine, alpha-L-fucose and sulfate groups. ACP and HOP had almost identical ratios of glucuronic acid, N-acetyl-galactosamine and fucose. However, the sulfate contents and sulfation patterns of fucose residues of ACP and HOP were obviously different. There were 4-O-sulfated fucose,3,4-O-disulfated fucose and 2,4-O-disulfated fucose in ACP, but only 3-O-sulfated fucose and 2,4-O-disulfated fucose were present in HOP. Therefore, their distinct anticoagulant activities might be due to the different sulfate contents and sulfation patterns of their fucose residues. (C) 2014 Elsevier Ltd. All rights reserved.