低分子量坛紫菜多糖纳米硒的制备、表征及其体外抗氧化活性

Preparation,Characterization and in Vitro Antioxidant Activity of Low Molecular Weight Porphyra haitanensis Polysaccharides Nano-selenium

目的:制备低分子量坛紫菜多糖纳米硒(SPS-SeNPs),检测其形态特征及抗氧化活性。方法:以多糖浓度、反应时间、反应温度作为实验因素,采用双波长比色法测定SPS-SeNPs中纳米硒(SeNPs)的粒径变化,以SPS-SeNPs溶液的吸光度比值(A410/490)为评价指标,采用单因素及正交试验考察SPS-SeNPs的制备工艺。使用扫描电子显微镜、透射电子显微镜、X射线衍射和X射线光电子能谱分析对SPS-SeNPs进行结构表征。研究其总抗氧化活性、还原能力、DPPH自由基清除率。结果:制备SPS-SeNPs最佳条件为:多糖浓度2 mg/mL,反应温度为40℃,反应时间为0.5 h,该条件下制备出的SPS-SeNPs溶液吸光度比值为2.0487±0.0082。SPS-SeNPs中的SeNPs呈现出具有良好分散性的球形形态。确定了SPS-SeNPs的元素组成百分比为:C元素(42.00%)、O元素(41.35%)、Se元素(16.65%)。证实了SPS-SeNPs中的Se为0价态的无定形硒。通过稳定性考察发现SPS-SeNPs能在4℃避光保存30 d仍保持稳定。与亚硒酸钠(Na2SeO3)和低分子量坛紫菜多糖(SPS)相比,SPS-SeNPs表现出良好的总抗氧化能力、还原能力和DPPH自由基清除能力(IC50=31.45±1.16μg/mL)。结论:SPS-SeNPs结合了多糖和纳米硒的优点,既具有多糖的抗氧化性,又具有纳米硒的高生物活性。这为进一步开发和利用坛紫菜粗多糖提供了重要的理论依据。

Objective:This study endeavors to synthesize selenium nanoparticles(SPS-SeNPs)by low molecular weight Porphyra haitanensis polysaccharide,with a primary focus on assessing their morphological attributes and antioxidant efficacy.Methods:Polysaccharide concentration,reaction time,and reaction temperature were systematically manipulated to optimize the preparation process.The preparation process of SPS-SeNPs was systematically investigated through both single-factor and orthogonal experiments.The determination of SeNPs particle size within SPS-SeNPs was executed via dual-wavelength colorimetry,with the absorbance ratio(A410/490)of the SPS-SeNPs solution serving as a pivotal evaluation metric.Structural elucidation encompassed scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray diffraction(XRD),and X-ray photoelectron spectroscopy(XPS).The investigation extended to the assessment of total antioxidant activity,reducing power,and DPPH free radical scavenging rate.Results:The optimal conditions for SPSSeNPs preparation were ascertained at a polysaccharide concentration of 2 mg/mL,a reaction temperature of 40℃,and a reaction time of 0.5 h,resulting in an absorbance ratio of 2.0487±0.0082.SeNPs within SPS-SeNPs exhibited a welldispersed spherical morphology.The elemental composition percentages of SPS-SeNPs were found to be as follows:C(42.00%),O(41.35%),and Se(16.65%).The selenium within SPS-SeNPs was validated to be in an amorphous state with a zero valence,maintaining stability over 30 days at 4℃under dark storage conditions.It demonstrated outstanding total antioxidant capacity,reducing power,and DPPH free radical scavenging ability(IC50=31.45±1.16μg/mL),surpassing the performance of sodium selenite(Na2SeO3)and low molecular weight P.haitanensis polysaccharides(SPS).Conclusions:SPS-SeNPs synergistically harness the antioxidative properties of polysaccharides and the heighten biological activity of nano-selenium,thereby furnishing substantial theoretical underpinning for the progressive development and application of crude P.haitanensis polysaccharides.