Abstract:In anaerobic bottles fermentation, glucose, fructose, xylose, lactose, maltose, sucrose and sugar alcohols could be used to produce succinic acid with Actinobacillus succinogenes. When sorbitol was utilized as the carbon source in the batch fermentation, more succinate and ethanol were produced compared with those using glucose, while producing less acetate and formate. The metabolic flux analysis results showed that the flux partitioning at PEP node was stable when glucose was replaced by sorbitol, but the flux partitioning at PYR and AcCoA nodes changed a lot because more reducing power (NADH) was generated to meet the more requirement the synthesis of succinate and ethanol.