Research Article
Optimization of Fermentation Conditions of the Engineered Corynebacterium Glutamicum to Enhance L-Ornithine Production by Response Surface Methodology
Dong-Mei Lu, Ling-Yan Jiang, Lu-An Chen, Jian-Zhong Liu* and Zong-Wan MaoThe Key Laboratory of Gene Engineering of Ministry of Education and Biotechnology Research Center, Sun Yat-Sen University, Guangzhou 510275, P.R.China
- Corresponding Author:
- Jian-Zhong Liu
The Key Laboratory of Gene Engineering of Ministry of
Education and Biotechnology Research Center
Sun Yat-Sen University, Guangzhou 510275, P.R.China
Tel: 86-20-84110115
Fax: 86-20-84110115
E-mail: lssljz@mail.sysu.edu.cn
Received date: November 01, 2011; Accepted date: November 05, 2011; Published date: November 07, 2011
Citation: Lu DM, Jiang LY, Chen LA, Liu JZ, Mao ZW (2011) Optimization of Fermentation Conditions of the Engineered Corynebacterium Glutamicum to Enhance L-Ornithine Production by Response Surface Methodology. J Biotechnol Biomaterial 1:116. doi: 10.4172/2155-952X.1000116
Copyright: © 2011 Lu DM, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Abstract
Optimization of fermentation conditions for L-ornithine production using the engineered Corynebacterium glutamicum ATCC13032 (? argF? pro? kgd) was carried out by one-factor-at-a-time, Plackett-Burman, the steepest ascent design and a response surface methodology. Addition of Tween 80, tricarboxylic acid cycle intermediates (KAc and succinic acid) improved L-ornithine production. Using Plackett-Burman design, glucose, (NH4)2SO4, MgSO4- 7H2O and yeast extract were screened as significant factors. Response surface methodology was used to further optimize the fermentation medium. The optimized medium contained (g/L): glucose 80.00, yeast extract 13.99, (NH4)2SO4 37.94, MgSO4-7H2O 1.58, KH2PO4 1.00, K2HPO4 0.50, Na2HPO4 0.50, FeSO4-7H2O 0.02, MnSO4-4H2O 0.02, molasses 2.00, KAc 5.00, succinic acid 5.00, CaCO3 10 and Tween 80 1ml (addition after 8 h of fermentation). L-ornithine production was increased by 197 % compared to that under unoptimized conditions. 18.17 g/L of L-ornithine production was obtained at 60 h of fermentation in 5 L bioreactor by the engineered Corynebacterium glutamicum, which is the highest level in engineered strain so far.