Enhancement of 2-keto-L-gulonic production in Gluconobacter oxydans Through Feeding Metalions

Abstract:

To further increase the production of 2-keto-L-gulonic acid by Gluconobacter oxydans,the effects of six different metal ions were determined,based on the analysis of L-Sorbosone pathway.It was found that Fe3+,Mg2+,Mn2+ can enhance the cell growth and 2-KLG production.Then,an optimum concentration of those three metal ions was achieved by developing a multivariate quadratic equation: Fe3+ 0.21 mmol/L,Mn2+ 9.98 mmol/L,and Mg2+ 4.23 mmol/L.By using the optimum combination,the production of 2-keto-L-gulonic reached at 65.1 g/L,which is 144.4% higher than that of the control.