桉木预水解液中半纤维素多糖分离纯化及抗氧化活性研究

Study on Separation, Purification and Antioxidant Activities of Hemicellulose Polysaccharides from Eucalyptus Pre-hydrolysate

关键词:  预水解液  多糖  分离纯化  抗氧化活性

Key Words:pre-hydrolysate  polysaccharides  separation and purification  antioxidant activity

摘要:采用醇沉法从桉木预水解液中提取半纤维素粗多糖（PHLP），并利用DEAE-650M离子交换柱对其进行分离纯化，对纯化得到的中性多糖PHLP-1和酸性多糖PHLP-2两种组分进行分析。单糖组分结果表明，PHLP-1和PHLP-2均由阿拉伯糖、木糖、半乳糖、甘露糖及葡萄糖组成，摩尔比分别为0.09∶1∶0.13∶0.07∶0.35和0.1∶1∶0.03∶0.09∶0.08。红外光谱测定表明，两种组分均具有多糖的特征吸收峰。扫描电子显微镜表明，PHLP-1和PHLP-2呈无序杂乱的结构形态。抗氧化实验结果表明，两种纯化的多糖组分均具有一定的抗氧化性且存在量效关系，抗氧化能力强弱顺序为：PHLP-2＞PHLP-1＞PHLP。

Abstract:The hemicellulose polysaccharides （PHLP） were extracted from the eucalyptus wood pre-hydrolysate （PHL） by alcohol precipitation， and were separated and purified by DEAE-650M ion exchange column. Meanwhile， the two purified components neutral polysaccharide PHLP-1 and acidic polysaccharide PHLP- 2 were analyzed. The results of monosaccharide components showed that both PHLP-1 and PHLP-2 were composed of arabinose， xylose， galactose， mannose and glucose， with a molar ratio of 0.09∶1∶0.13∶0.07∶0.35 and 0.1∶1∶0.03∶0.09∶0.08. The infrared spectroscopy showed that both components had characteristic absorption peaks of polysaccharides. The scanning electron microscopy analysis showed that the structures of PHLP-1 and PHLP-2 were disordered and messy. The results of antioxidant experiments showed that the two purified polysaccharides had certain antioxidant properties and there was a dose-effect relationship. The order of antioxidant ability was： PHLP-2>PHLP-1>PHLP.