论文信息 - Parallel substrate feeding and pH-control in shaking-flasks.

Parallel substrate feeding and pH-control in shaking-flasks.

An intermittent feeding system for shaking-flasks was developed to close the gap between batch operated shaking-flasks and fed-batch operated as well as pH-controlled stirred tank reactors. A precise syringe pump was connected via a substrate distribution system to individual 2/2-way miniature valves, one for each of up to 16 shaking-flask. The shaking-flasks were equipped with pH-probes. A process computer controls the intermittent feeding of substrates by tracking predefined individual feeding profiles as well as the base (or acid) addition for individual pH-control of the shaking-flasks. Higher concentrations of aerobic cells with higher cellular activities were achieved in fed-batch operated and pH-controlled shaking-flasks as compared to the conventional batch operation. Physiological effects of an intermittent feeding were studied in a stirred tank reactor with a recombinant E. coli strain, which expressed the GDP-mannose-pyrophosphorylase enzyme under the control of the lac-promoter.

[1] Dirk Weuster-Botz,et al. Parallel Bubble Columns with Fed‐Batch Technique for Microbial Process Development on a Small Scale , 1999 .

[2] C. Wandrey,et al. Medium Optimization by Genetic Algorithm for Continuous Production of Formate Dehydrogenase , 1995 .

[3] M Ahman,et al. Response of guanosine tetraphosphate to glucose fluctuations in fed-batch cultivations of Escherichia coli. , 1995, Journal of biotechnology.

[4] P Neubauer,et al. Influence of substrate oscillations on acetate formation and growth yield in Escherichia coli glucose limited fed‐batch cultivations , 1995, Biotechnology and bioengineering.

[5] L. Elling,et al. Expression, purification and characterization of recombinant phosphomannomutase and GDP-alpha-D-mannose pyrophosphorylase from Salmonella enterica, group B, for the synthesis of GDP-alpha-D-mannose from D-mannose. , 1996, Glycobiology.

[6] R. Dale,et al. A Continuous Feeding Assembly for Laboratory Fermentations , 1953, Applied microbiology.

[7] C. Wandrey,et al. Use of a genetic algorithm in the development of a synthetic growth medium for Arthrobacter simplex with high hydrocortisone Δ1-dehydrogenase activity , 1995 .

[8] A H Emery,et al. Approximation of continuous growth of Cephalotaxus harringtonia plant cell cultures using fed‐batch operation , 1991, Biotechnology and bioengineering.