title: Effect of sodium accumulation on heterotrophic growth and polyhydroxybutyrate (PHB) production by Cupriavidus necator.
abstract: This study evaluates the effect of sodium (Na(+)) concentration on the growth and PHB production by Cupriavidus necator. Both biomass growth and PHB production were inhibited by Na(+): biomass growth became zero at 8.9 g/L Na(+) concentration while PHB production was completely stopped at 10.5 g/L Na(+). A mathematical model for pure culture heterotrophic PHB production was set up to describe the Na(+) inhibition effect. The parameters related to Na(+) inhibition were estimated based on shake flask experiments. The accumulated Na(+) showed non-linear inhibition effect on biomass growth but linear inhibition effect on PHB production kinetics. Fed-batch experiments revealed that a high accumulation of Na(+) due to a prolonged growth phase, using NaOH for pH control, decreased the subsequent PHB production. The model was validated based on independent experimental data sets, showing a good agreement between experimental data and simulation results.
authors.affiliation: Flemish Institute for Technological Research (VITO), Business Unit Separation and Conversion Technology, Boeretang 200, 2400 Mol, Belgium; Ghent University, Department of Biosystems Engineering, Coupure Links 653, 9000 Gent, Belgium. Electronic address: mdsalatulislam.mozumder@ugent.be.
authors.forename: Md Salatul Islam
authors.initials: MS
authors.lastname: Mozumder
authors.affiliation: Flemish Institute for Technological Research (VITO), Business Unit Separation and Conversion Technology, Boeretang 200, 2400 Mol, Belgium.
authors.forename: Linsey
authors.initials: L
authors.lastname: Garcia-Gonzalez
authors.affiliation: Flemish Institute for Technological Research (VITO), Business Unit Separation and Conversion Technology, Boeretang 200, 2400 Mol, Belgium.
authors.forename: Heleen
authors.initials: H
authors.lastname: De Wever
authors.affiliation: Ghent University, Department of Biosystems Engineering, Coupure Links 653, 9000 Gent, Belgium.
authors.forename: Eveline I P
authors.initials: EI
authors.lastname: Volcke
mesh_terms: D002138:Calibration; D020118:Cupriavidus necator / Q000378:metabolism*; D006885:Hydroxybutyrates / Q000378:metabolism*; D008954:Models, Biological; D012964:Sodium / Q000378:metabolism*
chemical_list: D006885:Hydroxybutyrates; D012964:Sodium
keywords: Biomass growth; Mathematical modeling; Na(+) inhibition; Polyhydroxybutyrate (PHB) production; Simulation