Dissolved Oxygen concentration analysis of L-Lysine Fermentation Production by Corynebacterium glutamicum

Abstract

The L-lysine fermentation by Corneybacterium glutamicium was investigated in this study. The objective was to improve the process performance by manipulating cellular environment conditions. The main factor under consideration was dissolved oxygen concentrations in the fermentation broth. To implement effective process control, a process model was developed based on combined kinetic study and material balances. The process dynamics at the dissolved oxygen tensions (DOTs) of 5%, 10% and 20% was analyzed. The results showed that inhibition of high oxygen level could occur during the early growth phase and depressive effect of low oxygen availability was confined to the rest of the process, suggesting that different fermentation stages required different DOTs. Batch experiments were conducted with 5% DOT for the rest of fermentation. The final L-Lysine concentration reached 52.7g/L compared with 40g/L The low DOT settings required much less energy for agitation and aeration.