Optimization of anaerobic fermentation of Actinobacillus succinogenes for increase the succinic acid production

Abstract

Succinic acid is a four-carbon dicarboxylic acid used as a building-block in the synthesis of valuable commodities and specialty chemicals. Succinic acid is produced petrochemically by hydrogenation of maleic anhydride and a “greener” alternative route is microbial fermentation. In this study, a 25−1 fractional factorial design (FFD) and a subsequent central composite rotatable design (CCRD) were used to investigate the influence of process parameters on succinic acid and biomass concentration during fermentation by Actinobacillus succinogenes. The independent factors were glucose concentration (19.29–42.45 g/L), yeast extract concentration (5–11 g/L), temperature (33–41 °C), pH (6–8), and agitation speed (100–300 rpm). Results showed that the main factors that influenced the succinic acid production were pH, yeast extract concentration and temperature. According to the CCRD results, the optimum conditions for succinic acid production were 37–41 °C, 13 g/L yeast extract concentration and pH 7. The maximum succinic acid concentration obtained was 17.5 g/L.