Fig. 1

Growth and production of different Ustilaginaceae strains grown on glucose with limiting ammonium chloride concentration (1 g/L NH4Cl). (A) Course of the oxygen transfer rates. Arrows indicate start of nitrogen limitation. (B) Itaconic acid titers, optical densities and yields of ITA on glucose after 78 h of cultivation. Cultivations were performed in a 96 round deep-well MTP, filled with 300 µL modified Verduyn medium with 25 g/L glucose at 30 °C, 350 rpm shaking frequency and a shaking diameter of 50 mm. 100 mM and 30 mM MES were added to the U. maydis and U. cynodontis cultivations, respectively. The initial pH was set to 6.5 for all cultures. Graphs in (A) show the mean of three replicates, with standard deviation as shaded area. Due to high reproducibility of the measurements, the standard deviation might not be visible for every data point. For clarity, only every fourth data point is shown