An anticoagulative polysaccharide from an enzymatic hydrolysate of Ecklonia cava

In this study, seven brown algal species (Ecklonia cava, Ishige okamurae, Sargassum fulvellum, Sargassum horneri, Sargassum coreanum, Sargassum thunbergii and Scytosiphon lomentaria) were enzymatically hydrolyzed using five carbohydrases (Viscozyme, Celluclast, AMG, Termamyl and Ultraflo) and screened for their potential anticoagulant activity. E. cava was the most potent anticoagulant inhibitor of the seven species. The active polysaccharide fraction of the AMG enzymatic extract of E. cava was purified using anion-exchange chromatography on DEAE-cellulose and gel filtration chromatography on Sepharose 4B. According to the polyacrylamide gel electrophoresis, the purified compound showed a high molecular weight. The highly sulfated (0.92 sulfate/total sugar) active sample was mainly composed of fucose and small amount of galactose. The anticoagulant compound studied was detected by prolongation of activated partial thromboplastin time (APTT), thrombin time (TT) and prothrombin time (PT). As it was revealed by APTT assay, the pure sulfated polysaccharide from E. cava at 0.7 μg/ml showed almost similar anticoagulant activity to that of heparin. According to the results of activated coagulation factor assay, the purified compound strongly interferes with coagulation cascade by inhibiting biological activity of serine proteases II, X and VII.