玉米麸皮半纤维素由来的各分子质量片段的制备及鉴定

Identification and Molecular Mass Determination of Fragments from Corn Bran Hemicellulose

目的:为探讨玉米麸皮半纤维素生理活性与其分子大小的关系,采用体外的方法制备玉米麸皮半纤维素由来的各分子质量片段。方法:采用纯乙醇沉淀法、内源性木聚糖酶水解法和酸分解法制备各分子质量片段,通过薄层层析和基质辅助激光解析电离化-飞行时间质谱进行鉴定及分子质量测定。结果:玉米麸皮半纤维素多糖、玉米麸皮半纤维素低聚糖和玉米麸皮半纤维素单糖分别为分子质量在20～140ku范围的阿拉伯木聚糖,分子质量在286～930u的木糖低聚糖和木糖阿拉伯低聚糖以及分子质量为157u的木糖、阿拉伯糖。本研究结果可为玉米麸皮半纤维素生理活性研究打下基础。

Objective： to investigate the relationship between intestinal fermentation and physiological functions, fragments from corn bran hemicellulose were prepared. Methods： Each fragments were prepared by pure ethanol precipitation, endo-xylanase hydrolysis and acid hydrolysis. Their identification and molecular mass determination were carried out by TLC and MAIDI-TOF MS. Result： The main component of corn bran hemieellulose polysaccharides was determined to be arabinoxylan with MM above 20 ku; the main component of oligosaccharides was a large amount of xylobiose and a small amount of xylo-oligosaecharides or xylo- arabino-oligosaccharides with polymerization degree（DP） of 3-7 with precise MM ranging from 285.7 to 930.1; the main component of monosaccharides was xylose and arabinose with MM of 157.2 and a trace amount of oligosaccharides with MM from 285.8 to 523.1 （DP 2-4）. The study will lay a foundation for the further research of its physiological activity.