Effect of dilution rate in continuous production of l-ornithine by an arginine auxotrophic mutant

Optimization of Fermentation Conditions of the Engineered Corynebacterium Glutamicum to Enhance L-Ornithine Production by Response Surface Methodology

“…The level of Lornithine production is 9 times higher than that (2 g/L) of the classically obtained auxotrophic mutant Brevibacterium ketoglutamicum BK533 in a batch culture [14]. However, it is lower than that (74 g/L) of the auxotrophic mutant Brevibacterium ketoglutamicum BK533 in a fed-batch culture by shorten the mixing time of the limiting nutrient in the fermenter [16].…”

“…In our lab, we constructed a triple gene knockout strain C.glutamicum ATCC13032 ( argFproBkgd) for L-ornithine production, which could produce 4.62 g/L of L-ornithine [13]. The level of L-ornithine production of the engineered strain is higher than that of the industrial strain Brevibacterium ketoglutamicum BK533 (2 g/L) under unoptimized conditions [14]. In order to further investigate the effect of conditions and to improve L-ornithine production, it is desirable to optimize the medium.…”

“…Lee et al [15] reported that yeast extract as an arginine source and ammonium sulfate as an inorganic nitrogen source had significant effects on L-ornithine production and cell growth in Brevibacterium ketoglutamicum. Model of fed-batch culture, dilute rate and dual limitation of arginine and phosphate in continuum culture were also optimized for L-ornithine production and cell growth in Brevibacterium ketoglutamicum BK533 [7,14,16]. After these optimization, Brevibacterium ketoglutamicum BK533 production L-ornithine up to 74 g/L in a fed-batch culture by shorten the mixing time of the limiting nutrient in the fermenter [16] from 2 g/L in a batch culture [14].…”

Metabolic evolution of Corynebacterium glutamicum for increased production of L-ornithine

“…Those researchers achieved this yield by using a 7-L fed-batch fermentation process with a glucose-feeding strategy and an L-arginine auxotrophic mutant of Brevibacterium ketoglutamicum ATCC 21092. The titre of this auxotrophic mutant, which was generated using classical mutagenesis, was only 2 g/L in batch culture [35]. This suggests that the yield of the new strains described in this study may be enhanced by growth using fed-batch fermentation technology.…”