Succinic Acid Production By Fermentation Using Corn Stover Hydrolysate

Succinic acid is an intermediate of tricarboxylic acid cycle. It’s also an important C4-dicarboxylic acid which has been widely used as a precursor of many industrially important chemicals in chemical, food and pharmaceutical industries. Corn stover is the agriculture waste which can be obtained from corn and it’s also a renewable resources. In this paper, we use acid-enzymatic two-steps hydrolysis of corn fiber to obtain reducing sugar. And it focused on the study of the growth and succinic acid production by Actinobacillus succinogenes X-1in facultative anaerobic fermentation. It discussed the feasibility of replacement of glucouse by corn fiber as the carbon source for fermentation succinic acid. And the conditions of succinic acid complex extraction from fermentation broth were studied.In this study, The corn stover hydrolysate was used as the carbon source, the High Performance Liquid Chromatography (HPLC) was used to analysis hydrolyzed corn stover components. To produce succinic acid Actinobacillus succinogenes X-1for strains of different single sugar as carbon source, explore actinobacillus succinic acid production in the growth of different single sugar, the experimental results showed that the producing succinic acid actinobacillus can use different single sugar, broad-spectrum carbon source assimilation ability. Maize straw hydrolysis sugar was used as carbon source, anaerobic fermentation technological conditions for producing succinic acid were reducing sugar concentration of42.8g/L, the yeast extract concentration was12.5g/L, buffer of15.9g/L MgCO3, fermentation temperature of37℃, anaerobic fermentation of48h, The yield of succinic acid was29.1g/L.The process parameters of extracting succinic acid with acid crystallization were: adjusting the pH to2.0, enrichment distillation and crystallization precipitation, putting in4℃for4h, filtering, the succinic acid crystallization was obtained. Through research and analysis, The yield and purity was71.8%and92.4%, respectively. A molar ratio of hydrogen cation to succinic salts of2.2:1and a reaction time of12h were established. Favorite succinate purification methodology was determined using Box-Behnken design. An addition of3.3%activated carbon to the mixture, a decoloring temperature of72℃and time of37min were set. The purity and yield of the succinates obtained were98.4%and84.23%respectively.Corn straw which is crop waste hydrolyzed was used as raw material to get hydrolyze corn stover. The hydrolyzed corn straw and producing succinic acid actinobacillus were used as carbon source and experimental strain, the intermittent fermentation and biological transformation were operated to produce succinic acid. That expands the new ways of biological refining and provides a scientific basis for industrialized production of bio-based succinic acid.