Patent GB-689032-A (GB)
Title: Process for the production of streptomycin
IPC: C12P19/54
Filed: 1948-12-10
Abstract: A process for preparing streptomycin comprises fermenting an aqueous nutrient medium not initially containing streptomycin under submerged aerated conditions with the resistant strain produced by a process which comprises as its first stage propogating a streptomycin-producing strain of S. griseus in a nutrient medium containing an initial streptomycin concentration at least sufficient to retard growth of the organism, and thereafter performing successive propagation stages in each of which the culture formed in the preceding stage is employed to inoculate a new medium, the initial streptomycin concentration of each nutrient medium increasing from a selected value for the first stage to a higher value for the last stage, until a resistant strain of S. griseus is obtained which will grow well in media containing an initial concentration of at least 500 microgram/ml. of streptomycin.  The streptomycin concentration in the new medium is preferably about 100 microgram/ml. higher than the concentration in the previous propagation. Preferably, but not essentially, the nutrient medium in the second and later stages has a higher streptomycin concentration than its preceding stage.  In an example: (1) a resistant strain of S. griseus was obtained by propagating standard S. griseus (Waksman No. 4) in an aqueous medium containing pepticase, sodium chloride, dextrose, dipotassium phosphate, magnesium-, zinc- and ferrous sulphates, calcium chloride and 250 microgram/ml. of streptomycin.  After incubation part of the culture was used to inoculate a similar medium containing 500 micrograms/ml. streptomycin.  In stages part of the culture-containing mycelium from successive incubations is used to inoculate nutrient media containing initially 400, 500, and 600 microgram/ml. of streptomycin, to give a strain of S. griseus capable of normal growth and sporulation in media containing initially 600 micrograms/ml. of streptomycin. Streptomycin is produced by incubation of aqueous media inoculated with this strain and containing (2A) dextrose, digested casein, sodium chloride, beef extract; (2B) as (2A) with the addition of dipotassium phosphate; (3) sodium chloride, dextrose, sodium nitrate, magnesium-, zinc, and ferrous sulphates, dipotassium phosphate, calcium chloride and Pfeiffer's dried yeast.ALSO:A process for the production of streptomycin-resistant strains of S. griseus comprises as its first stage propagating a streptomycin-producing strain of S. griseus in a nutrient medium containing an initial streptomycin concentration at least sufficient to retard growth of the organism, and thereafter performing successive propagation stages in each of which the culture formed in the preceding stage is employed to inoculate a new medium propagating the organism in said medium, the initial streptomycin concentration of each nutrient medium increasing from a selected value for the first stage to a higher value for the last stage until a resistant strain of S. griseus is obtained which will grow well in media containing an initial concentration of at least 500 micrograms/ml. of streptomycin.  The streptomycin concentration of each new medium is preferably about 100 micrograms/ml. higher than that employed in the previous propagation.  Preferably, but not essentially, the nutrient medium in the second and later stages has a higher streptomycin concentration than its preceding stage.  In example (1) a standard S. griseus (Waksman No. 4) is propagated in an aqueous medium containing pepticase, sodium chloride, dextrose, dipotassium phosphate, magnesium-, zinc-, and ferrous sulphates, calcium chloride and 250 micrograms/ml. of streptomycin.  After incubation, part of the culture medium was used to inoculate a similar medium containing 500 micrograms/ml. of streptomycin.  In stages part of the culture containing mycelium from successive incubations is used to inoculate nutrient media containing initially 400, 500, and 600 micrograms/ml. of streptomycin, to give a strain of S. griseus capable of normal growth and sporulation in media containing initially 600 micrograms/ml. of streptomycin.  This strain is used in the production of streptomycin (see Group IV (b)).