Modeling and Analysis of a New Process for Pyruvate Production

Abstract

Early process development is crucial for the economic and environmental performance of a final production process. A new process for the production of pyruvate is presented as a case study to show how process modeling and an analysis of the results regarding economic and environmental aspects improves the understanding of the process, its cost structure, and its environmental impact. It also enables the quantification of process improvements and the comparison of alternative designs. The model of the pyruvate production shows how strain and fermentation improvements propagate through the process and affect its economic and environmental performance. The comparison of two alternative purification concepts, liquid extraction and electrodialysis, show that electrodialysis is a promising approach for the purification of pyruvic acid.

CRISPRi enables fast growth followed by stable aerobic pyruvate formation in Escherichia coli without auxotrophy

“…The production of pyruvate by biotechnical means is well established, for example, by Toray Industries using Torulopsis glabrata [ 1 , 2 ]. Processes with high titer, yield and productivity have been described not only for T. glabrata but also for E. coli [ 3 , 4 , 5 ] and the economic feasibility of E. coli as a pyruvic acid producer from glucose has been examined in a case study [ 6 ]. However, applications of pyruvate are relatively few compared to other small organic acids: Pyruvate primarily serves as an additive for the synthesis of small‐volume specialty chemicals or pharmaceuticals such as L‐DOPA and is sold as a food additive [ 7 , 8 ].…”

“…Pyruvate is usually produced from glucose and gene deletions or mutations with high impact on the catalytic activity of the pyruvate dehydrogenase complex result in acetate auxotrophy in aerobic conditions [ 18 ]. Whereas this enables decoupling of growth and pyruvate production, it also implies that any demand for reducing power and ATP exceeding the supply provided from glycolysis must be met by the co‐consumption of acetate which increases process cost and complexity [ 6 ]. Several studies have thus explored the possibility of throttling the flux from pyruvate to acetyl‐CoA to trigger the accumulation of pyruvate while maintaining a low level of flux through the TCA cycle to avoid acetate auxotrophy.…”

Isolation and scale-up of sodium pyruvate from fermentation broth using a repulsive extraction and crystallization method

“…Various downstream approaches have been reported for the separation of carboxylic acids or their salts from dilute biological solutions. They include: (a) the use of ion‐ exchange chromatography methods, which produces sodium pyruvate of 96–98% purity; (b) low yield membrane processes; (c) organic solvent extraction; (d) recovery by electrodialysis; and (e) reactive extraction methods, which produces sodium pyruvate of purity 97% with yield of 71–80% …”

Study of a cleaner extraction of pyruvic acid from fermentation broth

“…include organic solvent extraction (Uchuio et al, 1976;Chen et al, 2000;Biwer et al, 2005), reverse osmosis method and ion exchange process Li et al, 2001b;Huang et al, 2007;Zhao et al, 2010).…”