嗜热链球菌CH9胞外多糖的分离纯化及结构分析.pdf

※棊酣研究
品
2012.Vol.33.Vo.I9I07
嗜热链球菌CH9胞外多糖的分离纯化及
结构分析
张新源,刘会平,曹春玲,季玲
(天津科技大学食品工程与生物技术学院,教育部食品营养与安全币点实验家,天津300457)
摘要:对嗜热链球南CI胞外多糖进行分离纯化,经DAE-52离子交换柱及 Sephadex G-100凝胶柱得到单一组
分,利用高效液相色谱( HIPLC)测其分子质量,结果表明:EPS1a为中性多糖,分了质量为1.8×10°u;EPS2a、
HIPS3a为酸性多糖,分子质量分別为106×10°、1.05×103u。经琼脂糖凝胶电泳及 Sephadex(i-100凝胶柱定3种糖
均为单一組分。紫外及红外光谱扫描结果显示:3种糖均具有多糖的特征吸收峰,且HPS2a、FPS3a可能为糖与蛋白
的复合物。刚果红实验表明:EPS1a具有二股螺旋结构,而其他两种糖并木发现此現象。戶消去实验证明:EPS1a、
EPS3a为ーO一连接,EPS2a为N一连接。
关键词:嗒热链球菌;胞外多糖;分离纯化;结构分析
Purification and Structural Characteri ation of Exopolysaccharide Produced by Streptococcus thermophils CH9
/HAN(i Xin-yuan, I IU Hui-ping, CAO Chun-ling, JI Iin
(Key Laboratory of Tood Nutrition and Safety, Ministry of Education, School of Tood En ineering and Biological Technology.
Tianjin University of Science and Technology, Tianjin 300457, China)
Abstract rude exopolysaccharides(EPS)isolated from the fermentation supernatant of Sreptococcus thermophils CI9
were fractionated by DEAE-52 column chromatography into EPSL, EPS2 and EPS3. Sephadex G-100 column chromatography
was used to further Fractionate the three factions Lo harvest their respective major components named as Fpsla, FPS2A and
EPS3A, rcspectively. Epsla was a neutral polysaccharide with a molccular wcight o[ 1.8X 10 u, and EPS2A and EPS3A wre
acidic polysaccharides with a molecular weight of 1.06X 10 u and 1.05 X 10. respectively. Agarose gel electrophoresis
analysis indicated that all these three polysaccharides consisted of a single component. UV and IR spectroscopic analyses
showed that all of them had characteristic adsorption peaks o! polysaccharide. EPS2A and EPS3A might be polysaccharide
prout complc es. ong e sl reale whal Epsla raher han EPS2A and Ps3a had a three-stranded helix s reture Bcla
elimination test demonstrated that EPS la and EPS3A were-o-iinked but EPS2A was a-n-linked polysaccharide
Key words: Streptococcus thermophils CH9: exopolysaccharides; purification; structural characterization
中图分类号:TS252
文献标识码:A
文章编号:1(002-663002012)19-0107-06
乳酸菌胞外多糖( lactic acid bacteria exopolysaccharide,甚至还含有一些难以去除的杂质,有些EPS结合蛋自质
LAB EPS)是乳酸菌在生长代谢过程中分泌到细胞壁外的或肽类形成糖-蛋白或糖-肽复合物,因此需要进一步纯
黏液或荚膜多糖,它们都是适应环境的产物叫。近年来,化以得到高纯度的多糖。有些乳酸菌能够产生一种以上
对LAB上EPS的研究逐渐増多,其保健功能如抗肿瘤、抑的EPS,如果分离和纯化方法不当可能很难将这些EPS分
菌、消炎、调节免疫等为研究的重点?。
离纯化出来。工 AB EPS虽然种类很多,分子质量较大,
EPS的分离纯化是多糖结构解析以及研究功能特性分子质量范聞一般在10×10~6.0×10u之问,但是其重
的基础。,初步分离得到的IPS可能是多种多糖的混合物,复单元相对简单,其单糖组成中一般总含有の-葡萄糖、
收稿日期
基金项目:天津科技大学引进人オ科研启动基金项目(20080420)
作者简介:张新源(1985),女,帜土研究生,研究方向为食品加工技术及乳品加工技术。F- mail: Zhangxinyuan6285400l63,com
通信作者:刘会半(1965一),男,教授,博士,研究方向为乳品科学与新技术、功能性蛋自及活性肽、益生菌选育及应用的
研究。E-mail: liuhuiping( tust edu.cn
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