In-vitro Anticoagulant Activities of Natural Polymer Derivatives - Konjac Glucomannan Sulfate

摘要

Nowadays, natural polysaccharides with high biocompatibility and bioactivity are extensively developed in the biomedicine field. Chemical modification has been successfully applied to enhance the functional properties of polysaccharides, and the degree of substitution and the distribution of substituted groups are verified to have a great effect on the bioactivity of polysaccharide derivatives. Sulfated polysaccharides showed great blood-compatibility and even anticoagulant activity. Konjac glucomannan (KGM) is a water-soluble non-ionic polysaccharide with high molecular weight derived from the tuber of Amorphophallus konjac, which consists of main chain of [3-1,4-D-mannose and D-glucose (molar ration of 1.6:1) with some mannoses branch at the C-3 position attached by one acetyl group per 19 sugar residues. Sulfated KGM had similar structure and functional groups (sulfate and uronic units) to heparin sulfate, which was evaluated as an important category with biological activities and then widely used for anticoagulant therapy for more than 50 years. This paper reported the preparation of KGM sulfate (KGMS) with different substituted degree by a simple reaction with chlorosulfonic acid (CSA) in N,N-dimethylformamide (DMF). The molecular characteristics of KGMS were investigated by infrared spectroscopy, element analysis, and size exclusion chromatography-laser light scattering binding devices. At the same time, their anticoagulant activities were evaluated by activated partial thrombin time (APTT), thrombin time (TT) and prothrombin time (PT).