| The influence of air saturation and temperature on continuous citric acid secretion was studied in chemostat cultures of Candida oleophila ATCC 20177 (var.). Simultaneous measurements of intra- and extracellular concentration of glucose, citric and isocitric acid confirmed the involvement of a specific active transport system in citrate secretion, favouring citric acid over isocitrate. An optimum air oxygen saturation of 20% and temperature of 30-31ºC were determined for the continuous citric acid secretion. The highest values of citric acid concentration (98 g/L), citrate to isocitrate ratio (33.3:1), volumetric citric productivity (1.8 g/(L x h)), and specific citric acid productivity (0.1 g/(g x h)), were reached at 20% air saturation at a... |
