polysaccharide molecular weight control method for streptococcus pneumoniae serotype 19a

摘要

"Method for polysaccharide molecular weight control for streptococcus pneumoniae serotype 19a". The present invention relates to improved methods for producing a solution containing high molecular weight isolated streptococcus pneumoniae capsular polysaccharides 19a. In certain methods, a bacterial cell fermentation culture of streptococcus pneumoniae producing capsular polysaccharides for serotype 19a is fermented for less than 6 hours before the bacterial cells are lysed and the capsular polysaccharides are harvested. In other methods, co2 is supplied to the fermentation culture. The supply of co2 to the fermentation culture includes the addition of bicarbonate ions to the fermentation culture, the addition of carbonate ions to the fermentation culture, the addition of mixtures of bicarbonate and carbonate ions to the fermentation culture, and overlapping of the culture. of fermentation with co2.