地皮菜糖蛋白-硒复合物的制备、结构表征及抗氧化性研究

Preparation, Structural Characterization and Antioxidant Activity of Nostoc Commune Vaucher Glycoprotein-Selenium Complex

以地皮菜为原料提取糖蛋白,并优化糖蛋白-硒复合物制备工艺,探究其结构表征及抗氧化活性。以产率和硒含量为评价指标,利用正交设计优化地皮菜糖蛋白-硒复合物制备工艺,采用红外、X射线衍射、扫描电镜等方法表征糖蛋白-硒结构,从DPPH自由基清除率、ABTS自由基清除率、·OH自由基清除率和总还原能力等4个方面考察地皮菜糖蛋白-硒复合物抗氧化活性。结果表明,地皮菜糖蛋白-硒复合物最佳制备工艺为亚硒酸钠与糖蛋白质量比1:1、反应温度75 ℃、0.4 g亚硒酸钠与糖蛋白混合物中添加BaCl_(2)0.5 g、反应时间7 h,产率为32.57%,硒含量为1.40 mg/g。红外图谱显示硒化并未对地皮菜糖蛋白主要官能团和结构造成显著改变;X射线衍射图谱显示地皮菜糖蛋白-硒复合物主要形态为无定形态;扫描电镜显示地皮菜糖蛋白-硒复合物片状形貌较小。体外抗氧化结果显示,地皮菜糖蛋白-硒复合物具有较强还原能力,能够清除DPPH自由基、ABTS自由基和·OH自由基。

Glycoprotein was extracted from Nostoc commune Vaucher,and the process of glycoprotein-selenium complex was optimized to explore its structural characterization and antioxidant activity.Taking the yield and selenium content as evaluation indexes,the preparation process of Nostoc commune Vaucher glycoprotein-selenium complex was optimized by orthogonal design.The structural characterization of glycoprotein-selenium complex was characterized by infrared,X-ray diffraction and scanning electron microscope.The antioxidant activity of glycoprotein-selenium complex was investigated by DPPH·,ABTS;·,·OH radical scavenging rate and total reducing ability analysis.The results showed that the optimum preparation process of Nostoc commune Vaucher glycoprotein-selenium complex was as follows:the mass ratio of Na;SeO;to glycoprotein was 1:1,the reaction temperature was 75 ℃,the amount of BaCl_(2) in the 0.4 g raw material was 0.5 g,the reaction time was 7 h,the yield was 32.57%,and the selenium content was 1.40 mg/g.Infrared spectra showed that selenylation did not significantly change the main functional groups and structure of glycoprotein.X-ray diffraction patterns showed that the main form of glycoprotein-selenium complex was amorphous.Scanning electron microscopy showed that the flake morphology of glycoprotein-selenium complex was small.In vitro antioxidant results showed that the glycoprotein-selenium complex had strong reducing ability and could scavenge DPPH·,ABTS;· and ·OH free radical.