两种富硒黄牛肝菌伞多糖的制备、表征及其抗氧化活性

Preparation,Characterization and Antioxidant Activity of Two Selenium-Enriched Polysaccharides from Suillellus luridus

硒是人体必需的微量元素之一,但由于其安全域值较低,极易导致硒中毒。研究发现,硒化多糖和纳米硒有更高的安全性和生物活性,是理想的补硒制剂。本研究以黄牛肝菌伞多糖(polysaccharides from Suillellus luridus,SLPC)为原料制备硒化黄牛肝菌伞多糖(selenide polysaccharides from Suillellus luridus,Se-SLPC)和纳米硒-黄牛肝菌伞多糖(nano-selenium-polysaccharides from Suillellus luridus,SLPC-SeNPs),比较硒化修饰前后多糖的理化性质和结构特性,观察SLPC-SeNPs的表面形貌并测定其稳定性,同时,评价两种富硒多糖的抗氧化活性。结果表明,Se-SLPC的硒含量为1.62 mg/g,是由半乳糖、葡萄糖和甘露糖组成的多糖,平均分子质量8.2 kDa,核磁共振分析显示取代反应发生在C4和糖苷键连接位点C3处。SLPC-SeNPs粒径为55.46 nm,表面呈均匀球状,在4℃下能稳定保持至少80 d。此外,Se-SLPC和SLPC-SeNPs的抗氧化活性均明显高于SLPC。本研究可为研发安全高效的补硒制剂提供理论支撑。

Selenium is an essential trace element for human body,but it can easily cause poisoning because of its low safety threshold.Previous studies have demonstrated that selenized polysaccharides and nano-selenium have higher safety and biological activity,and so they are ideal selenium supplements.In this study,selenized polysaccharides(Se-SLPC)and nano-selenium-polysaccharide(SLPC-SeNPs)were prepared from the polysaccharides of Suillellus luridus(SLPC),the physicochemical and structural properties of the raw and selenized polysaccharides were compared,and the surface morphology and stability of SLPC-SeNPs were determined.Additionally,the antioxidant activities of both seleniumrich polysaccharides were evaluated.The results showed that the selenium content of Se-SLPC was 1.62 mg/g,whose polysaccharide moiety was composed of mannose,glucose,and galactose and had an average molecular mass of 8.2 kDa.Nuclear magnetic resonance(NMR)spectroscopic analysis showed that the substitution reaction took place at the C4 position and at the glycosidic linkage position C3.The SLPC-SeNPs have a particle size of 55.46 nm and a uniform spherical surface,which can be stably maintained at 4℃for at least 80 d.In addition,both Se-SLPC and SLPC-SeNPs had significantly higher antioxidant activity than SLPC.This study can provide data support for the development of safe and efficient selenium supplements.