Effect of metal ions on fermentation and metabolization of Actinobacillus Succinogenes NJ113

The effects of adding Mg2+,Mn2+,Co2+ on cell growth and succinic acid production was investigated.The metabolic flux of Actinobacillus succinogenes NJ113 was calculated.It was found that the flux of HMP increased by 445.38%,176.23 % and 171.67% after adding 6 mmol/L Mg2+,6 mmol/L Mn2+,2 mmol/L Co2+ respectively,thus the reducing power was better balanced.The flux of C4 was 57.70%,15.94% and 2.91% higher respectively,which led to the improvement of succinic acid flux by 62.69%,18.91% and 5.01%.The key enzyme activity analysis showed that the specific activity of PEP carboxykinase(Pck)reached 568.732 U/mg,728.049 U/mg and 339.686 U/mg with 6 mmol/L Mg2+,6 mmol/L Mn2+,2 mmol/L Co2+ addition respectively.As a result,the concentration of succinc acid was 27.83 g/L,26.27 g/L,and 23.54 g/L,while the concentration of control was only 22.79 g/L.