The effects of cultural conditions on growth and secondary metabolism in<i>Streptomyces thermoviolaceus</i>

Abstract

Granaticin, an isochromate quinone antibiotic is synthesized as a secondary metabolite by Streptomyces thermoviolaceus. Antibiotic productivity was investigated under a variety of cultural conditions, including complex and defined media, mesophilic and thermophilic temperatures and a variety of sole carbon sources. In a defined medium growth was supported, to varying extents, by different carbon sources and in most cases granaticin production was observed. Highest biomass and granaticin yields were obtained when cultures were grown in the presence of xylan, fructose, glutamate or proline as carbon source. Changes in pH during growth affected both the timing and extent of granaticin production.