Preparation, characterization and in vitro anticoagulant activity of corn stover xylan sulfates
Preparation, characterization and in vitro anticoagulant activity of corn stover xylan sulfates
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DOI：
10.1080/09205063.2016.1264060
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发表时间：
2017-01-01
影响因子：
3.6
通讯作者：
Zhan, Huai-Yu
中科院分区：
文献类型：
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作者：
Cheng, He-Li;Liu, Hao;Zhan, Huai-Yu
通过均相反应将硫酸酯基团引入玉米秸秆木聚糖中，制备了一种新型抗凝血剂。以N，N-二甲基甲酰胺（DMF）、二甲基亚砜（DMSO）和甲酰胺（FA）为反应介质，LiCl为辅助溶剂，研究了反应条件对反应的影响。通过FT-IR和（CNMR）-C-13对产物进行结构表征，结果表明，在三种介质中，SO 3·Py复合硫酸化试剂均能成功合成木聚糖硫酸酯（XS）。研究了硫酸化温度、硫酸化时间、介质种类和-SO 3/-OH摩尔比对取代度（DS）和聚合度（DP）的影响。DMF/LiCl比DMSO/LiCl和FA/LiCl更有利于制备高取代度的硫酸木聚糖。结果表明，SO_3·Py络合物在DMF/LiCl体系中，以-SO_3：-OH = 1.5：1，在50 ℃下反应3 h为最佳反应条件。硫酸化过程中木聚糖的聚合度降低，DMF/LiCl比DMSO/LiCl或FA/LiCl对木聚糖的降解最少。用活化部分凝血活酶时间（APTT）、凝血酶时间（TT）和凝血酶原时间（PT）测定了不同取代度的硫酸木聚糖的抗凝血活性。结果表明，硫酸基的引入使木聚糖具有抗凝血活性。DS为1.20的XS在20 g/mL剂量下的APTT和TT值分别为141和45.3s，而空白样品的APTT和TT值仅为35.5和15.6s。随着DS和XS浓度的增加，混凝时间延长。我们的研究结果为农业生物质的增值利用提供了新的见解。
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 and (CNMR)-C-13 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 degrees C for 3h. 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 45.3s at a dosage of 20g/mL, while the APTT and TT values for the blank sample were only 35.5 and 15.6s. 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.