Optimization of culture conditions in CO2 fixation for succinic acid production using Actinobacillus succinogenes

摘要

The culture conditions in CO2 fixation by Actinobacillus succinogenes for succinic acid production were investigated by a model of available CO2 in a 3-l fermentor. The results from the model analysis showed that the available CO2 for succinic acid production in the fermentation broth is the sum of HCO3 (-), CO3 (2-), and CO2 influenced by external culture conditions such as medium components, CO2 partial pressures, and temperature. The optimized conditions for CO2 supply in a 3-l fermentor were determined as follows: CO2 partial pressure and stirring speed were maintained at 0.1 MPa and 200 r min(-1), respectively, with a pH of 6.8 and a temperature of 37A degrees C; 0.15 mol l(-1) NaHCO3 was added. Under the optimized conditions, a CO2 fixation rate of 0.57 g l(-1) h(-1) was obtained, and a succinic acid concentration of 51.6 g l(-1) with a yield of 75.8% was reached. These results suggest that optimized conditions of CO2 supply are effective in high succinic acid production and thus have potential applications in succinic acid production and CO2 fixation.