Anticoagulant activity of sulfoalkyl derivatives of curdlan

Curdlan is a natural β-1, 3-glucan produced byAgrobacterium biovar 1. In this study, the anticoagulant activity of sulfoalkyl derivatives of curdlan was investigated by carrying out activated partial thromboplastin time (APTT) assay and compared with that ofo-sulfonated curdlan. Approximately 100-fold higher concentration ofo-sulfonated curdlan than heparin was required to obtain the same level of the clotting time. Anticoagulant activity of curdlan derivatives was dependent on the degree of sulfation in prolonging the clotting time. However, the chain length of the substituent did not play a role in prolonging the clotting time. The curdlan derivatives enhanced thrombin inhibition by mediating through antithrombin III. The inhibition of thrombin byo-sulfonated curdlan was found to be approximately 10-fold weaker than that by heparin.