Production Of Succinic Acid Using Corn Cob Hydrolysate

Succinic acid, a dicarboxylic acid with the molecular formula of C4H6O4, is regarded as one of the most important platform chemicals. The production of succinic acid from lignocellulosic feedstocks is of growing interest worldwide. In this study,19 strains with the capability of producing succinic acid were isolated from bovine rumen contents. The highest yield of succinic acid was 6.59 g/L by the strain 10B in fermentation lasted 48 h in the corn cob hydrolysate medium containing 20 g/L of xylose. The strain Actinobacillus succinogenes 130Z was applied to set up the process of succinic acid production from corn cob hydrolysate. The medium was optimized by response surface methodology (RSM), and the optimized medium contained 41.41 g/L of xylose (from corn cob hydrolasate),11.04 g/L of yeast extract, and 38.66 g/L of MgCO3. In the process of fermentation, succinic acid was produced with cell growth. In 34 h,22.33 g/L of xylose were consumed, and the titer and yield of succinic acid achieved 17.81 g/L and 79.76%, respectively. In addition, the genetic manipulation system for Actinobacillus succinogenes was also performed, several knckout/shuttle vectors were constructed based on different strategies.