B群链球菌培养条件的优化研究

Studies on the optimal culture conditions of Streptococcus group B

利用B群链球菌 (StreptococcusGroupB ,SGB)有可能发展一种新的预防用疫苗。为研究其生长特性 ,对该菌在不同培养条件下的生长状况进行了研究。分别考察了液体培养基、接种量、pH值、生长因子、溶氧等因素对SGB生长的影响。结果发现 :SGB液体培养基生长因子中尿嘧啶、烟酸、泛酸钙等对SGB的生长有较大影响 ,葡萄糖最佳浓度为 14g/L ;此外 ,发酵培养最佳接种量为 0 .5～ 0 .8亿 /ml;最适pH值为 7～ 8,培养过程中调节pH、补加葡萄糖能维持SGB继续生长 ;增大溶氧对SGB生长影响不明显。在此优化基础上 ,连续进行 3批 10 0L发酵 ,SGB菌生长良好 ,荚膜多糖产量可观。

Streptococcus group B (SGB) may be utilized to devlop a new vaccine for prophylaxis.In order to systematically study the growth characteristics of Streptococcus group B(SGB), the bacterium was cultured in a series of culture conditions. Influencing factors ,including fluid medium ,the quantities of inoculation , growth factors ,pH value and dissolved oxygen were studied. The following results were obtained: The fluid medium was suitable for growth of SGB .The growth factors such as uracil ,nicotinic acid,pantothemate are necessary to the growth of SGB. The optimum concentration of glucose is 14g/L.A justing pH and adding glucose in the growth period of SGB can prolong the growth of SGB .The optimal quantity of SGB inoculation is 0.5-0.8×108/ml. The optimal pH value for SGB growth is 7-8 . In the experiment,the additional oxygen supply for SGB flask culture is not critical.Three batch of fermentations were made , the growth of SGB is well and the yield of capsule polysaccharide of SGB is abundant.