Materials Science Centre, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal 721302, India.
Int J Biol Macromol. 2011 May 1;48(4):705-12. doi: 10.1016/j.ijbiomac.2011.02.019. Epub 2011 Mar 5.
Bacillus pumilus UW-02, an isolate from agricultural soil irrigated with waste water was found to produce a carbohydrate polymer in the form of extracellular polysaccharide (EPS) in glucose mineral salts medium (GMSM). The recovery rates of EPS by ion-exchange and gel filtration chromatography were around 63% and 90%, respectively. As evident from HPLC and FT-IR analyses, the EPS was found to be a heteropolymer consisting glucose, mannose, xylose, arabinose, and N-acetyl glucosamine as monomer units. Different oligosaccharide combinations namely hexose(4), hexose(6) pentose(1) and hexose(10) pentose(1) are obtained after partial hydrolysis of EPS using MALDI-ToF-MS. Electron micrographs portrayed the intense affinity of the EPS molecules for each other, thereby justifying its viscosifying and thickening properties. The EPS with an average molecular weight of 218 kDa and thermal stability up to 180 °C showed pseudoplastic rheology and significant emulsifying activities.
从农业土壤中分离出的一株蜡样芽孢杆菌 UW-02，在含有葡萄糖的无机盐培养基（GMSM）中产生胞外多糖（EPS）。离子交换和凝胶过滤色谱法的 EPS 回收率分别约为 63%和 90%。从 HPLC 和 FT-IR 分析来看，EPS 被发现是一种由葡萄糖、甘露糖、木糖、阿拉伯糖和 N-乙酰葡萄糖胺组成的杂多糖。用 MALDI-ToF-MS 对 EPS 进行部分水解后，得到了不同的低聚糖组合，即六糖（4）、六糖（6）戊糖（1）和六糖（10）戊糖（1）。电子显微镜图像显示 EPS 分子之间强烈的亲和力，从而证明了其增稠和增稠特性。EPS 的平均分子量为 218 kDa，热稳定性高达 180°C，表现出假塑性流变学和显著的乳化活性。
