Baker C J, Kasper D L
Infect Immun. 1976 Jan;13(1):189-94. doi: 10.1128/iai.13.1.189-194.1976.
The yield of purified type III polysaccharide of group B Streptococcus was significantly improved by modification of the growth medium. Culture of organisms in standard Todd-Hewitt broth resulted in acid accumulation during the exponential phase of growth and poor yield of type III polysaccharide when extracted from cells by washing with neutral buffer solution. By increasing the buffering capacity of the broth medium, acid accumulation was prevented, and the number of viable cells was increased at the stationary phase of growth. Further, by increasing the concentration of glucose in the buffered medium, the yield of type III polysaccharide was increased two to three times. Electron microscopic investigations of cells grown in the modified broth medium demonstrated a thicker microcapsule than was found in organisms grown in standard broth.
通过改良生长培养基，B族链球菌III型纯化多糖的产量得到显著提高。在标准托德-休伊特肉汤中培养微生物时，在生长指数期会积累酸，并且当用中性缓冲溶液洗涤从细胞中提取III型多糖时，产量很低。通过提高肉汤培养基的缓冲能力，可以防止酸的积累，并且在生长稳定期活细胞数量增加。此外，通过提高缓冲培养基中葡萄糖的浓度，III型多糖的产量提高了两到三倍。对在改良肉汤培养基中生长的细胞进行电子显微镜研究表明，其微荚膜比在标准肉汤中生长的微生物的微荚膜更厚。
