该研究以兰州百合多糖和FeCl3为原料，以Fe3+含量为评价指标，采用单因素实验及Box-Behnken响应面法优化兰州百合多糖铁（III）配合物制备工艺，获得最佳参数；采用红外光谱（Infrared Spectroscopy，IR）和紫外可见光光谱法（Ultraviolet-Visible Spectroscopy，UV）进行其结构分析，通过对DPPH自由基和ABTS+自由基清除能力评价兰州百合多糖铁（III）配合物体外抗氧化活性。结果表明，兰州百合多糖铁（III）配合物的制备最佳工艺为反应温度61.10 ℃、pH值6.92、反应时间1.38 h，在此反应条件下，兰州百合多糖铁（III）配合物Fe3+含量为7.32%；IR和UV分析表明说明兰州百合多糖成功与Fe3+螯合；兰州百合多糖铁（III）配合物和兰州百合多糖清除DPPH自由基的半抑制浓度（Half-maximal Inhibitory Concentrations，IC50）分别是0.63 mg/mL和0.79 mg/mL，清除ABTS+自由基的IC50分别是0.71 mg/mL和0.76 mg/mL。该研究成功制备了具有抗氧化活性的兰州百合多糖铁（III）配合物，为兰州百合资源的高值化利用和大健康新产品开发提供了一定的理论依据。

Lanzhou lily polysaccharides and ferric chloride were used as raw materials to prepare the Lanzhou lily polysaccharide-Fe (III) complex. The preparation conditions were optimized using the Fe3+ content as the evaluation index based on a single-factor experimental design and Box-Behnken response surface methodology. The structure of the polysaccharide-Fe(III) complex was analyzed using infrared spectroscopy and ultraviolet-visible spectroscopy, and its in vitro antioxidant activity was evaluated based on the DPPH and ABTS+ radical scavenging abilities. The results showed that the optimal parameters for the preparing Lanzhou lily polysaccharide-Fe(III) complex were as follows: reaction temperature of 61.10 ℃, pH of 6.92, and reaction time of 1.38 h. The Fe3+ content of the complex was 7.32% under these reaction conditions. The results of infrared and ultraviolet analyses indicated that Lanzhou lily polysaccharides chelated with Fe3+. Furthermore, the half-maximal inhibitory concentrations of the Lanzhou lily polysaccharide-Fe(III) complex and Lanzhou lily polysaccharides against DPPH radicals were 0.63 and 0.79 mg/mL, respectively. The corresponding half-maximal inhibitory concentrations against ABTS+ radicals were 0.71 and 0.76 mg/mL, respectively. Additionally, the antioxidant activity of the complex was considerably stronger than that of lily polysaccharides. The Lanzhou lily polysaccharide-Fe(III) complex with antioxidant activity was successfully prepared. The findings of this study provide a theoretical foundation for maximizing the use of Lanzhou lily resources and creating new health products.

道地药材生态种植及质量保障项目（国中医药科技〔2020〕153号）；财政部和农业农村部：国家现代农业产业技术体系资助（CARS-21）；西北中藏药省部共建协同创新中心项目（Xbzzy-2022-01）；甘肃省科技重大专项（23ZDFA013-1）