玉竹多糖铁的制备及其理化性质研究

Study on Preparation and Chemical Characterization of IRON(Ⅲ)-Polygonatum odoratum Polysaccharides Complex

目的研究玉竹多糖铁(POPFe)配合物的合成方法及药用性能。方法采用微波萃取技术提取浙产玉竹中多糖,以玉竹多糖和三氯化铁为底物正交实验设计合成POPFe配合物,借助邻菲啰啉分光光度法和置换碘量法测定铁含量,通过红外光谱法对其进行了结构表征,并探讨了POPFe在水溶液中的稳定性及生理条件下释放铁的可能性。结果 POPFe最佳合成条件是多糖水提液与柠檬酸三钠的体积比4∶1,温度70℃,pH 9。在该条件下所得无定形黄棕色粉末,易溶于水,铁的质量分数为30.13%,其水溶液在pH值3～12内稳定。以抗坏血酸还原POPFe,铁在5 h内基本溶出。结论 POPFe是聚合多糖与多聚铁核形成的配合物,有望开发为新型补铁剂。

OBJECTIVE To prepare Polygonatum odoratum polysaccharide-iron （Ⅲ） complex （POPFe） and study its physicochemical properties. METHODS POPFe was synthesized by neutralization of FeCl3 carbohydrate solution. Orthogonal design was used to optimize the preparation process. The content of iron （Ⅲ） in POPFe was determined with o-phenanthroline spectrophotometry and iodometry. The surface structure of POPFe was studied by infrared spectroscopic technique. The deoxidization of POPFe was tested with colorimetric analysis. RESULTS The optimal preparation conditions were found as follows： the ratio of polysaccharides aqueous solution to sodium citrate solution as 4∶1, temperature 70 ℃ and pH 8-9. POPFe showed qualitatively identified reactions of Fe （Ⅲ）. The content of Fe （Ⅲ） in POPFe was 30.13%. The complex was stable at pH 3-12 without precipitation and dissociation. At 37 ℃, Fe （Ⅲ） in the complex was completely reduced to Fe （Ⅱ） by ascorbic acid in about 5 h. CONCLUSION POPFe can be developed as a new iron supplementary.