The effect of acetate on the production of citric acid by Aspergillus niger in submerged fermentation

Abstract

Two strains of Aspergillus niger showed a 57% and 40% reduction in growth in a shaken mineral medium with 5% glucose, at the initial pH 6.5–6.0 where ammonium acetate (0.25% and 0.2%) was a source of nitrogen. Uptake of glucose was not inhibited and mycelium kept its acid-forming activity. Growth inhibition was abolished in the presence of 12% glucose or increased content of ammonium and sodium acetate up to 765 mg acetate anion per 100 cm3.