An improved temperature-triggered process for glutamate production with Corynebacterium glutamicum

• Published in: Enzyme and microbial technology Vol. 25; no. 8; pp. 762 - 768
• Main Authors: Delaunay, S., Gourdon, P., Lapujade, P., Mailly, E., Oriol, E., Engasser, J.M., Lindley, N.D., Goergen, J.-L.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 01-11-1999; Elsevier Science
• Subjects: Addition reactions; Bacteria; Biological and medical sciences; Biotechnology; Cooling; Corynebacterium glutamicum; Fed-batch; Fermenters; Fundamental and applied biological sciences. Psychology; Glucose; Glutamate; glutamic acid; Methods. Procedures. Technologies; Microbial engineering. Fermentation and microbial culture technology; Organic acids; Organic compounds; Surface active agents; Temperature; Temperature; Fed-batch; Glutamate; Corynebacterium glutamicum; Process improvement; Production; Bacteria; Environmental factor; Actinomycetes; Corynebacteriaceae; Fermentation; Semicontinuous
• ISSN: 0141-0229; 1879-0909
• DOI: 10.1016/S0141-0229(99)00120-9

An improved glutamate-producing fed-batch process, using a temperature-sensitive strain of
Corynebacterium glutamicum, has been characterized. By a tight control of the culture temperature, it was possible to get industrially interesting performance as regards glutamate concentration, yield and productivity. A 24 h fermentation period enabled the production of 85 g/l of glutamate in the production phase induced after a temperature shift from 33°C to 39°C. The maximum specific production rate of glutamate was 0.63 g/g/h with a yield of 0.46 g of glutamate/gram of glucose. The two main co-products of the fermentation were lactate (11 g) and trehalose (12 g). Only trace amounts of other organic acids accumulated in the culture medium. This process offers an interesting alternative to currently employed fermentation strategies in which biotin limitation and/or surfactant addition is used to induce glutamate production. Simple control of fermentor cooling can be used to control the onset of the production phase, offering significant advantages from both an economic and a process robustness viewpoint.