title: Oxygen transfer in intensive microbial culture.
abstract: Oxygen transfer performances in intensive microbial cultures are compared with those occurring in coalescing and non-coalescing mineral media. E. coli fed-batch cultures are carried out in a 22 L bioreactor. Biomass concentrations of 80 g(DW) L(-1) are reached, with oxygen consumption rates of up to 0.6 mol L(-1) h(-1). To achieve these high transfer performances, dissipated power e reaches 35 kW m(-3). The hold-up in the culture broth and in the corresponding supernatant matches the non-coalescing mineral medium. Oxygen transfer coefficients, K (L) a in mineral media, and K (T) in the culture broth, are compared. K (T), calculated online from a gas balance method, excesses 1 s(-1). Yet, for given values of e, K (T) is 4-8 times lower than K (L) a determined in the non-coalescing mineral medium. The cell activity modifies the chemical medium properties and reduces the oxygen transfer conductance, as in a non-coalescing ionic medium containing surfactant.
authors: Laboratoire d'Ingénierie des Sytèmes Biologiques et des Procédés, UMR INSA-CNRS 5504, UMR INSA-INRA 792, Institut National des Sciences Appliquées, Toulouse Cedex 4, France. mathias.fyferling@insa-toulouse.fr
authors: Mathias
authors: M
authors: Fyferling
authors: Jean-Louis
authors: JL
authors: Uribelarrea
authors: Gérard
authors: G
authors: Goma
authors: Carole
authors: C
authors: Molina-Jouve
mesh_terms: D001671:Biochemistry / Q000379:methods*; D018533:Biomass; D019149:Bioreactors; D018929:Cell Culture Techniques / Q000379:methods; D002478:Cells, Cultured; D002623:Chemistry Techniques, Analytical / Q000379:methods; D004926:Escherichia coli / Q000201:enzymology* / Q000378:metabolism; D005285:Fermentation; D005947:Glucose / Q000737:chemistry; D007218:Industrial Microbiology / Q000379:methods; D007477:Ions; D007700:Kinetics; D010100:Oxygen / Q000737:chemistry*; D010101:Oxygen Consumption
chemical_list: D007477:Ions; D005947:Glucose; D010100:Oxygen