Culturing Streptococcus pyogenes - to yield antitumour agent streptolysin S, using sugar as carbon source and controlled pH

摘要

Streptococcuspyogenes is cultured in a medium containing fermentable sources of carbon, and at a pH of 5.6 or above throughout the whole culture period. The medium pref contains 0.1-5% fermentable C, such as mono- or di-saccharides esp glucose or sucrose. The pH is pref kept at 5.6-7.5 (6-7), by addn of an alkali. The culture medium is pref prepared by the addn of the fermentable carbon source to a yeast extract medium or a soya-peptone medium. Known cultures of S.pyogenes in the presence of fermentable carbon sources give an extremely poor yield of (I). Cultures in which the C source is not fermentable give (I) in moderate yeild, but the cells do not multiply very well. This new process gives a very healthy growth of S,pyogenes coupled with a good yield of (I).