Anthracycline production by Streptomyces capoamus in batch fermentation

Abstract

Anthracyclines have been intensely studied worldwide due to their importance as anticancer agents. In this work investigation was made on the production of ciclamycin, an antitumour complex of the anthracycline class, produced by Streptomyces capoamus. The fermentation medium consisted of glucose, as the main carbon source, and soymilk, as the sole nitrogen source. Experiments were performed in a 5-liter batch bioreactor under nitrogen and carbon-limiting conditions. Increasing antibiotic activity was observed both intra and extracellularly during growth under the two conditions used. Progressive loss of activity occurred in both cases after glucose was depleted from the medium. The results obtained showed that harvest of ciclamycin in a batch process should be controlled by the level of glucose in the reactor and that nitrogen should preferably be the limiting substrate. Alternatively, results indicate that extended production might be achieved in a fed-batch process where nitrogen was the limiting substrate.