title: Preparation, characterization and in vitro anticoagulant activity of corn stover xylan sulfates.
abstract: A new anticoagulant agent was prepared by introducing sulfate groups into corn stover xylan through homogeneous reactions. Three organic solvents, N, N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO) and formamide (FA), were adopted as reaction media, with the assistance of LiCl. Structural characterization by FT-IR and13CNMR showed that xylan sulfate (XS) could be successfully synthesized with SO3∙Pyridine (SO3∙Py) complexes sulfation reagent in the three media. The effect of sulfation temperature, sulfation time, media type and molar ratio of -SO3/-OH on the degree of substitution (DS) and degree of the polymerization (DP) were studied. DMF/LiCl were more effective than DMSO/LiCl and FA/LiCl in preparation of xylan sulfate with high DS. The optimal conditions for sulfation were obtained when SO3∙Py complex was added to DMF/LiCl with -SO3/-OH ratio of 1.5:1 and maintained at 50 °C for 3 h. Degree of polymerization of xylan was decreased during the sulfation process and DMF/LiCl offered the least xylan degradation as compared with DMSO/LiCl or FA/LiCl. Anticoagulant activities of the resultant xylan sulfates with different DS were evaluated by using activated partial thromboplastin time (APTT), thrombin time (TT), and prothrombin time (PT). Results indicated that the introducing of sulfate groups into xylan did endow the polysaccharides with anticoagulant activity. The APTT and TT of XS with DS of 1.20 reached 141 and 45.3 s at a dosage of 20 μg/mL, while the APTT and TT values for the blank sample were only 35.5 and 15.6 s. Furthermore, coagulation time was prolonged with the increase of DS and the concentration of XS. Our findings provide new insights into the value-added utilization of agricultural biomass.
authors.affiliation: a School of Chemical Science and Engineering , Tongji University , Shanghai , China.|b Hubei Provincial Key Laboratory of Green Materials for Light Industry , Hubei University of Technology , Wuhan , China.
authors.forename: He-Li
authors.initials: HL
authors.lastname: Cheng
authors.affiliation: c State Key Laboratory of Pulp and Paper Engineering , South China University of Technology , Guangzhou , China.
authors.forename: Hao
authors.initials: H
authors.lastname: Liu
authors.affiliation: b Hubei Provincial Key Laboratory of Green Materials for Light Industry , Hubei University of Technology , Wuhan , China.
authors.forename: Qing-Hua
authors.initials: QH
authors.lastname: Feng
authors.affiliation: b Hubei Provincial Key Laboratory of Green Materials for Light Industry , Hubei University of Technology , Wuhan , China.
authors.forename: Yi-Min
authors.initials: YM
authors.lastname: Xie
authors.affiliation: c State Key Laboratory of Pulp and Paper Engineering , South China University of Technology , Guangzhou , China.
authors.forename: Huai-Yu
authors.initials: HY
authors.lastname: Zhan
mesh_terms: D000925:Anticoagulants / Q000737:chemistry* / Q000494:pharmacology*; D001777:Blood Coagulation / Q000187:drug effects; D006801:Humans; D008970:Molecular Weight; D013431:Sulfates / Q000737:chemistry*; D014990:Xylans / Q000737:chemistry* / Q000494:pharmacology*; D003313:Zea mays / Q000737:chemistry*
chemical_list: D000925:Anticoagulants; D013431:Sulfates; D014990:Xylans
keywords: Xylan sulfate; anticoagulant; corn stover; homogeneous reaction