Observations on Streptomyces griseus

Synthetic mediums are extremely useful in the investigation of fermentation problems. Because of this fact, various laboratories that are interested in streptomycin have been engaged in developing synthetic mediums for the production of this antibiotic. VanderBrook et al. (1946) reported the use of a near synthetic medium composed of glucose, ammonium sulfate, mineral salts, and 0.1 per cent "curbay B-G." Saunders and Sylvester (1947) used a synthetic medium containing glucose, an organic acid, an inorganic nitrogen compound, and mineral salts. The synthetic medium of Hubbard and Thornberry (1946) was composed of a carbohydrate, the ammonium salt of lactic acid, and mineral salts. It will be noted that these mediums contain inorganic nitrogen compounds or the ammonium salt of an organic acid as the nitrogen source. Although these mediums supported growth and streptomycin production by Streptomyces griseus, the reported broth potencies thus obtained were not exceptionally high. This paper deals with various compounds, both organic and inorganic, as possible nitrogen sources for growth and streptomycin production in a synthetic medium.