Purification, characterization and in vitro anticoagulant activity of polysaccharides from Gentiana scabra Bunge roots

• Resin methods were employed to remove the proteins and pigments from polysaccharides of Gentiana scabra Bunge roots.
• The weight-average molecular weights of purified polysaccharides (named GSP-2 and GSP-3) were analyzed by HPGPC.
• Monosaccharide compositions of polysaccharide fractions were measured by HPAEC-PAD.
• GSP-3 showed significant anticoagulant activity in APTT and TT assays.

Three water-soluble polysaccharide fractions (GSP-1, GSP-2 and GSP-3) were obtained from Gentiana scabra Bunge roots by DEAE-Sepharose CL-6B and Sepharose CL-6B column chromatography. Their chemical characterizations were determined by high performance gel permeation chromatography (HPGPC), high performance anion exchange chromatography coupled with pulsed amperometric detection (HPAEC-PAD) and Fourier transform infrared (FT-IR) spectrometer. Moreover, their in vitro anticoagulant activities were evaluated by activated partial thromboplastin time (APTT), thrombin time (TT) and prothrombin time (PT) assays. GSP-1 and GSP-2 were composed of rhamnose, arabinose, galactose, glucose and galacturonic acid, while GSP-3 consisted of rhamnose, arabinose, galactose and galacturonic acid with a weight-average molecular weight of 5.8 × 104 Da. In comparison with the control group (saline), GSP, GSP-1, GSP-2 and GSP-3 could prolong APTT and TT, but not PT. Overall, GSP-3 exhibited potent anticoagulant activity and would be expected to be a potential source of anticoagulant.