Process for the production of nourseothricine and its adsorbate

Process for the production of nourseothricin, its salts or adsorbate, comprising cultivation of nourseothricin-forming streptomycetes stock, streptomyces noursei ZIMET 43716 under submersed aerobic culture conditions in a suitable nutrient medium containing carbon and nitrogen sources and mineral salt, and subsequent isolation of the active substance, comprising adding to the nutrient medium water-soluble zinc salt, in a 0.2 to 1.75 milimolar concentration, .beta.-alanine in a 0.25 to 1.75 milimolar concentration, alkali metal azide in a 0.05 to 0.25 milimolar concentration, pyrocatechol in a 0.20 to 1.75 milimolar concentration or ethyl isoamyl barbituric acid in a 0.25 to 1.75 milimolar concentration, performing a heat sterilization of the nutrient medium at a temperature from about 115.degree.-125.degree. C. in the presence of 0.10 to 1.75 milimolar concentration of a salt of zinc (II), iron (III), aluminum (III) or manganese (II), so that after conclusion of the sterilization a pH-value in the range from 7.2 to 8.8 is obtained, with or without addition of caustic soda before the sterilization, fermenting the main culture with a phosphate provision in a range from 0.1 up to 10 mg phosphate-phosphorus per liter medium per hour at a pH value from 5.0 to 6.5 over a period of 110-145 hours, at a fermentation temperature in the range from 26.degree.-32.degree. C., and with an oxygen partial pressure from 30 to 80%, as well as further substrate limitation to maintain a carbon-nitrogen ratio of 5 to 10 g glucose units to 0.015 to 0.2 g ammonium-nitrogen per liter medium, isolating the so-produced antibiotic by means of adsorption, eluting, concentrating, and then purifying, the antibiotic.