Enhancement of 2-keto-L-gulonic acid production using three-stage pH control strategy.
- Author:
Jing ZHANG
1
;
Jingwen ZHOU
;
Liming LIU
;
Jie LIU
;
Kejie CHEN
;
Guocheng DU
;
Jian CHEN
Author Information
1. Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China.
- Publication Type:Journal Article
- MeSH:
Bacillus megaterium;
growth & development;
metabolism;
Culture Media;
chemistry;
Fermentation;
Hydrogen-Ion Concentration;
Rhodobacteraceae;
growth & development;
metabolism;
Sorbose;
metabolism;
Sugar Acids;
metabolism
- From:
Chinese Journal of Biotechnology
2010;26(9):1263-1268
- CountryChina
- Language:Chinese
-
Abstract:
The aim of this study was to improve the 2-keto-L-gulonic acid (2-KLG) production efficiency by Ketogulonicigenium vulgare and Bacillus megaterium by using multi-stage pH control strategy. The effect of pH on the cell growths and 2-KLG production showed that the optimum pH for K. vulgare and B. megaterium cell growth were 6.0 and 8.0, respectively, while the optimum pH for 2-KLG production was 7.0. Based on the above results, we developed a three-stage pH control strategy: the pH was kept at 8.0 during the first 8 h, then decreased to 6.0 for the following 12 h, and maintained at 7.0 to the end of fermentation. With this strategy, the titer, productivity of 2-KLG and L-sorbose consumption rate were achieved at 77.3 g/L, 1.38 g/(L x h) and 1.42 g/(L x h), respectively, which were 9.7%, 33.2% and 25.7% higher than the corresponding values of the single pH (pH 7.0) control model.
