A chemically defined medium, consisting of d-fructose, l-glutamic acid, l-histidine, K2HPO4, MgSO4·7H2O, ZnSO4·7H2O, CaCl2·2H2O, FeSO4·7H2O, CoCl2·6H2O, and deionized water, was developed for synthesis of high yields (500 to 600 μg/ml) of actinomycin D by Streptomyces parvulus. Under these nutritional conditions, growth and actinomycin formation did not follow a typical trophophase-idiophase pattern. The amino acids appeared to have a sparing action on the utilization of d-fructose which was slowly and incompletely metabolized during mycelium development and antibiotic production. A significant repression of actinomycin synthesis by S. parvulus was observed when d-glucose (0.01 to 0.25%) was added to the culture medium. The repression was not due to a decline in the pH of the medium during glucose catabolism.
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