黄秋葵籽多糖的组成结构及抗氧化活性研究

Chemical compositions and antioxidant activities of Abelmschus esculentus L. Moench seed polysaccharides

中文关键词:  黄秋葵籽  多糖  化学组成  结构分析  抗氧化活性

英文关键词:Abelmoschus esculentus L. Moench seed  polysaccharide  chemical composition  structural analysis  antioxidant activity

中文摘要:

      目的 分析黄秋葵籽多糖(okra seed polysaccharides, OSPs)的组成结构并对其抗氧化活性进行评价。方法 样品经DEAE-52阴离子交换柱和Sephacryl S-400凝胶色谱柱分离纯化得到黄秋葵籽多糖, 采用尺寸排阻色谱柱分析其分子量, 并对其化学成分、单糖组成、糖苷键链接方式、傅里叶变换红外光谱(Fourier transform infrared, FT-IR)结构信息及抗氧化活性进行研究。结果 分离纯化的OSPs重均分子量(Mw)为7.09×105 Da, 数均分子量(Mn)为7.01×105 Da, Mw/Mn为1.01, 表明OSPs有较高的纯度, 得率为0.45%。酸降解和糖醇衍生化后经气相色谱测得OSPs由甘露糖、半乳糖、木糖、阿拉伯糖和鼠李糖组成, 摩尔百分比为36.98:31.29:15.61:8.87:3.37。FT-IR结果表明OSPs含有甘露糖残基。高碘酸氧化、Smith降解实验结果表明OSPs主要含有1→、1→6、1→2、1→2,6糖苷键。此外, OSPs具有良好的抗氧化能力, 特别是对O2-自由基的清除。结论 OSPs的组成结构初步被明确, OSPs具有良好的抗氧化能力, 本研究为黄秋葵籽资源的高值化利用提供理论基础。

英文摘要:

      Objective To analyze the composition structure of Abelmoschus esculentus L. Moench okra seed polysaccharides (OSPs) and evaluate its antioxidant activity. Methods OSPs was subjected to DEAE-cellulose-52 separation and Sephacryl S-400 HR gel filtration. The molecular weight (Mw) was determined by size exclusion chromatography, and the chemical compositions, monosaccharide compositions, glycosidic bond type, Fourier-transform infrared spectral (FT-IR) analysis information and antioxidant activities of OSPs were studied. Results The OSPs had a weight average molecular weight (Mw) of 7.09×105 Da and a number average molecular weight (Mn) of 7.01×105 Da, and Mw/Mn was 1.01, indicating that OSPs had good purity and the yield of OSPs was 0.45%. OSPs was determined to be composed of mannose, galactose, xylose, arabinose and rhamnose by gas chromatography after acid degradation and glycol derivation, and the mole percentage was 36.98: 31.29:15.61:8.87:3.37. FT-IR result represented the existence of mannose residue. The periodate oxidation and Smith degradation results indicated that the existence of 1→, 1→6, 1→2 and 1→2,6-linked glycosidic bonds. Besides, the OSPs exhibited effective antioxidant activities, especially against superoxide anion radicals. Conclusion The composition of OSPs has been preliminarily defined, and it has good antioxidant capacity. These investigations provide a theoretical basis for the high value utilization of okra seed resources.