怀山药多糖铁(Ⅲ)的组成及性能表征

Composition and property characterization of Rhizoma Dioscoreae polysaccharide-Fe (Ⅲ) complex

目的：对怀山药多糖铁（Ⅲ）复合物的性能进行表征并分析其组成。方法：从性状、溶解性及稳定性方面分析怀山药多糖铁的理化性质，利用红外及透射电镜技术分析怀山药多糖铁的表面结构。采用高温炉灰化法、湿法消化法和直接溶解法对怀山药多糖铁进行样品处理，用邻菲罗啉分光光度法测定复合物中铁含量。硫酸（苯酚法测定怀山药多糖铁中多糖含量。结果：怀山药多糖铁是无定形棕红色粉末，易溶于水，在pH3．8—11．6不沉淀、不水解。怀山药多糖铁是以聚合的β-FeOOH微核为核心，多糖在其表面配合形成的多糖铁（Ⅲ）表面复合物。3种样品处理方法测得的铁质量分数分别为17．05％，16，53％，17．10％。硫酸-苯酚法测得多糖质量分数为16．27％。结论：怀山药多糖铁（Ⅲ）为首次报道，生理条件下性质稳定，有望开发为新型补铁剂。

Objective： To characterize properties of Rhizoma Dioscoreae polysaccharide-Fe （Ⅲ） complex （RDPC） and analyze its composition. Method： Physicochemical properties, such as character, solubility and stability of RDPC were studied. Surface structure of RDPC was studied by Infrared spectroscopic technique and transmission electron microscopy. The content of Fe （ Ⅲ ） in RDPC was determined by o-phenanthroline spectrophotometry after being treated by ashing, wet digestion, or direct dissolution methods. Content of polysaccharide in RDPC was determined by sulphuric acid-phenol method. Result： RDPC was brownish red powder. It could dissolve in water, its aqueous solution was very stable at the pH from 3.8 to 11.6. RDPC was a surface complex in which poly- saccharide combined with β-FeOOH as core. The content ofFe （Ⅲ） in RDPC was 17. 05%, 16, 53%, 17. 10% respectively after being treated by 3 different pretreatment methods. Content of polysaccharide in RDPC was 16. 27%. Conclusion： This is the first report of RDPC which was stable under physiological pH conditions and could be a new candidate for iron-supplementary.