title: A novel milliliter-scale chemostat system for parallel cultivation of microorganisms in stirred-tank bioreactors.
abstract: A pH-controlled parallel stirred-tank bioreactor system was modified for parallel continuous cultivation on a 10 mL-scale by connecting multichannel peristaltic pumps for feeding and medium removal with micro-pipes (250 μm inner diameter). Parallel chemostat processes with Escherichia coli as an example showed high reproducibility with regard to culture volume and flow rates as well as dry cell weight, dissolved oxygen concentration and pH control at steady states (n=8, coefficient of variation <5%). Reliable estimation of kinetic growth parameters of E. coli was easily achieved within one parallel experiment by preselecting ten different steady states. Scalability of milliliter-scale steady state results was demonstrated by chemostat studies with a stirred-tank bioreactor on a liter-scale. Thus, parallel and continuously operated stirred-tank bioreactors on a milliliter-scale facilitate timesaving and cost reducing steady state studies with microorganisms. The applied continuous bioreactor system overcomes the drawbacks of existing miniaturized bioreactors, like poor mass transfer and insufficient process control.
authors.affiliation: Institute of Biochemical Engineering, Technische Universität München, Boltzmannstr. 15, 85748 Garching, Germany. Electronic address: a.schmideder@lrz.tum.de.
authors.forename: Andreas
authors.initials: A
authors.lastname: Schmideder
authors.affiliation: Institute of Biochemical Engineering, Technische Universität München, Boltzmannstr. 15, 85748 Garching, Germany. Electronic address: t.severin@lrz.tum.de.
authors.forename: Timm Steffen
authors.initials: TS
authors.lastname: Severin
authors.affiliation: Institute of Biochemical Engineering, Technische Universität München, Boltzmannstr. 15, 85748 Garching, Germany. Electronic address: johannescremer@web.de.
authors.forename: Johannes Heinrich
authors.initials: JH
authors.lastname: Cremer
authors.affiliation: Institute of Biochemical Engineering, Technische Universität München, Boltzmannstr. 15, 85748 Garching, Germany. Electronic address: d.weuster-botz@lrz.tum.de.
authors.forename: Dirk
authors.initials: D
authors.lastname: Weuster-Botz
mesh_terms: D061249:Batch Cell Culture Techniques / Q000295:instrumentation* / Q000379:methods; D019149:Bioreactors / Q000382:microbiology*; D004926:Escherichia coli / Q000254:growth & development*; D006863:Hydrogen-Ion Concentration; D015203:Reproducibility of Results
keywords: Chemostat; Escherichia coli; Growth kinetics; Miniaturized stirred-tank bioreactors; Scale-up