肉桂多糖的结构分析及抗氧化活性研究

Composition Analysis and Antioxidant Activity of Cinnamon Polysaccharide

为探讨肉桂多糖的抗氧化活性,将肉桂水提物(CE)除蛋白得到粗多糖,通过纤维素DE-52离子柱和丙烯葡聚糖凝胶S-300进行分级分离得到肉桂中性多糖(CNP)。经凝胶渗透色谱(GPC)法测定CNP的相对分子质量(M_(r)),柱前衍生高效液相色谱法测定肉桂中性多糖的单糖组分,通过甲基化法和核磁共振法测定其单糖的连接方式,采用体外化学模型研究CNP对DPPH·和ABTS^(+)·的清除作用。研究结果表明:CNP的重均相对分子质量(M_(w))为3630;主要的单糖为葡萄糖;单糖的3种连接方式为1,4,5-Ac_(3)-2,3,6-Me_(3)-Glu、1,5-Ac_(2)-2,3,4,6-Me_(4)-Glu、1,5,6-Ac_(3)-2,3,4-Me_(3)-Glu。CNP清除自由基测定结果表明:在质量浓度为2 g/L时,CNP对DPPH·的清除率达到最大为84%,ABTS^(+)·的清除率达到60%。虽然CNP对自由基的清除率比Vc低,但当CNP质量浓度较高(0.5 g/L)时对DPPH·的清除作用与Vc相当。因此CNP抗氧化活性良好,具有很好的开发价值。

In order to explore the antioxidant activity of cinnamon polysaccharides,the protein was removed from the water extract of cinnamon(CE)to obtain crude polysaccharides.By using cellulose ion column DE-52 and propylene dextran gel S-300,the cinnamon neutral polysaccharides(CNP)was obtained.The relative molecular mass(M_(r))of CNP was determined by gel permeation chromatography(GPC),and the monosaccharide component of CNP were determined by pre-column derivatization high performance liquid chromatography.The connection modes of its monosaccharides were determined by methylation method and nuclear magnetic resonance method.The in vitro chemical model was used to study the scavenging effects of CNP on DPPH·and ABTS^(+)·.The results indicated that the weight average relative molecular mass(M_(w))of CNP was 3630 and the main monosaccharide was glucose.Three kinds of connection modes of monosaccharides were 1,4,5-Ac_(3)-2,3,6-Me_(3)-Glu,1,5-Ac_(2)-2,3,4,6-Me_(4)-Glu,and 1,5,6-Ac_(3)-2,3,4-Me_(3)-Glu.The determination results of free radicals scavenging by CNP showed that when the mass concentration of CNP was 2 g/L,the DPPH·scavenging rate reached the maximum of 84%,the ABTS^(+)·scavenging rate reached 60%.Although the free radical scavenging rate of CNP was lower than that of Vc,the DPPH·scavenging effect was comparable to that of Vc when the concentration of CNP reached 0.5 g/L.Therefore,the antioxidant activity of cinnamon neutral polysaccharide was good and had good development value.