Williams A G, Wimpenny J W
J Gen Microbiol. 1977 Sep;102(1):13-21. doi: 10.1099/00221287-102-1-13.
Fermentation studies using batch culture indicated that exopolysaccharide production by Pseudomonas NCIBI1264 in a chemically defined medium increased under conditions of nitrogen limitation and excess carbon substrate at pH values above 6. The polysaccharide was formed from a variety of carbon substrates and its composition was not affected by the nature of the carbohydrate source. Polysacharide formation did not increase in media containing small amounts of phosphate, and, as in secondary metabolite production, it started late in the exponential growth phase continuing maximally after growth had ceased. The efficiency of glucose conversion into exopolysaccharide was low. Colorimetric, viscometric, and total carbon estimation techniques are described for determining exopolysaccharide levels in cell-free culture supernatants.
使用分批培养进行的发酵研究表明,在化学限定培养基中,假单胞菌NCIBI1264在氮限制和过量碳底物条件下,于pH值高于6时胞外多糖产量增加。该多糖由多种碳底物形成,其组成不受碳水化合物来源性质的影响。在含有少量磷酸盐的培养基中多糖形成没有增加,并且与次级代谢产物产生情况一样,它在指数生长期后期开始,在生长停止后继续最大程度地合成。葡萄糖转化为胞外多糖的效率很低。描述了用于测定无细胞培养上清液中胞外多糖水平的比色法、粘度测定法和总碳估计技术。