Abstract:The effects of five different kinds of corn steep liquor(domestic batch and solulys048K, solulys 095K,solulys 095E,No.120924,provided by Roquette Company) on succinic acid fermentation by Actinobacillus succinogenes NJ113 were studied. The feasibility of replacing yeast extract with corn steep liquor 095K and No.120924 as cheap nitrogen source was also studied. The results showed that 095K can replace yeast extract completely and the optimal replacement ratio was 60%-80% when using No.120924. The contents of amine acids,vitamins and metallic elements of corn steep liquor 095K were determined and the effect of the key ingredients on succinic acid production was studied by orthogonal experiment. A optimal combination of the six kinds of ingredients(glutamic acid,threonine,arginine,methionine,biotin and nicotinic acid) was obtained, and the yield of succinic acid was increased by 41.8% compared with that of the control.