Naslov
Process strategies to enhance pyruvate production with recombinant Escherichia coli: From repetitive fed-batch to in situ product recovery with fully integrated electrodialysis

Autori
Zelić, Bruno ; Gostović, Srđan ; Vuorilehto, Kai ; Vasić-Rački, Đurđa ; Takors, Ralf

Izvornik
Biotechnology and Bioengineering (0006-3592) 85 (2004), 6; 638-646

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
Pyruvate; E. coli; repetitive fed-batch; cell retention; electrodialysis; ISPR

Sažetak
Using the pyruvate production strain Escherichia coli YYC202 ldhA::Kan different process alternatives are studied with the aim of preventing a potential product inhibition by appropriate product separation. This strain is completely blocked in its ability to convert pyruvate into acetyl-CoA or acetate, resulting in acetate auxotrophy during growth in glucose minimal medium. Continuous experiments with cell retention, repetitive fed-batch and an in situ product recovery (ISPR) process with fully integrated electrodialysis were tested. Although the continuous approach achieved a high volumetric productivity (QP) of 110 g L-1 d-1, this approach was not pursued because of long-term production strain instabilities. The highest pyruvate/glucose molar yield of up to 1.78 mol mol-1 together with high QP 145 g L-1 d-1 and high pyruvate titers was achieved by the repetitive fed-batch approach. To separate pyruvate from fermentation broth a fully integrated continuous process has been developed. In this process electrodialysis was used as a separation unit. Under optimum conditions a (calculated) final pyruvate titer higher than 900 mmol L-1 (79 g L-1) was achieved.

Izvorni jezik
Engleski

Znanstvena područja
Biotehnologija

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