食品科学 ›› 2008, Vol. 29 ›› Issue (4): 267-271.

• 生物工程 • 上一篇    下一篇

双歧杆菌22-5胞外多糖结构分析

李伟欣, 陈倩, 李平兰, 吴广枫, 程静   

  1. 中国农业大学食品科学与营养工程学院; 中国农业大学食品科学与营养工程学院;
  • 出版日期:2008-04-15 发布日期:2011-08-24

Structural Study on Exopolysaccharide Produced by Bifidobacterium 22-5

 LI  Wei-Xin, CHEN  Qian, LI  Ping-Lan, WU  Guang-Feng, CHENG  Jing   

  1. College of Food Science and Nutritional Engineering, China Agricultural University
  • Online:2008-04-15 Published:2011-08-24

摘要: 本实验主要对双歧杆菌22-5胞外多糖(exopolysaccharide,EPS)结构进行了研究,单糖组成及红外检测信息提示,该EPS主要含有木糖、半乳糖、葡萄糖、阿拉伯糖、鼠李糖和岩藻糖,有羧基且部分成盐,存在吡喃糖环环内醚结构;GC-MS结果显示,EPS中含有大量的D-葡萄糖和D-半乳糖,其中D-半乳糖以4位连接为主,葡萄糖多为2,3,4,6连接;高碘酸氧化和史密斯降解后产物经GC检测进一步验证,该EPS不含1→,1→6键型,可能具有1→4、1→4,6和1→2、1→2,6连接,支链中可能含有葡萄糖和半乳糖;刚果红实验证明其可能具有螺旋结构。

关键词: 双歧杆菌, 胞外多糖, 多糖, 结构

Abstract: Bifidobacterium 22-5 from centenarians’ faeces produces an exopolysaccharide containing Xyl, Gal, Glu, Ara, Rha and Fuc. Infrared spectroscopy revealed that it contained pyranose, possessing the carboxyl group and a certain amount of carbonoxlate, and even the cycle ether. In addition, based on GC-MS, methylation analysis, NaIO4 oxidation and Smith degradation, the primary structure was elucidated. EPS was identified as a polymer containing 4-linked D- galactose. D- glucose partially took the form of the 2,3,4,6 connection, and 1-4 or 1-4,6 and 1-2 or 1-2,6 linkages, having neither 1-6 nor 1-linkages. Besides, D- glucoses and D-galactose may be as highly branched parts of the chain. It was also showed that the EPS may have the configure of helix in the Congo red test.

Key words: bifidobacterium, exopolysaccharide, polysaccharide, structure