title: Relationship between kinetics of growth and production of exo-electrons: Case study with Geobacter toluenoxydans.
abstract: Kinetics of growth and product formation of G. toluenoxydans DSMZ 19350 strain were investigated using sodium-acetate as substrate and Fe(3+)-ions and fumarate as electron acceptor. Response surface method was adapted for evaluation of growth of bacteria. Results showed that maximum growth was detected in the case of 2.2 g/L substrate concentration. Application of higher substrate concentration (>2.5 g/L sodium acetate) significantly inhibits the bacterial growth. Luong's model was found to be the most suitable to determine kinetic parameters (μ(max) = 0.033 1/h, KS = 0.205 g/L) of growth of G.toluenoxydans strain, and the growth was completely inhibited at substrate concentration higher than 3.1 g/L. In the case of product formation the Haldane model was used and kinetic parameters are μ(Pmax) = 0.123 mg/h, K(PS)= 0.184 g/L. Correlation between microbial growth and product formation was observed using the Luedeking-Piret empirical method. Both factors (growth and number of cells) affected significantly iron(III)-reduction, thus the product formation. These results are important and open the possibility to design a continuous MFC setting operating with G. toluenoxydans as biocatalyst.
authors.affiliation: Faculty of Food Science, Department of Brewing and Distilling, Corvinus University of Budapest , Menesi út 45, H-1118 Budapest , Hungary.
authors.forename: Attila
authors.initials: A
authors.lastname: Szöllősi
authors.affiliation: Faculty of Food Science, Department of Brewing and Distilling, Corvinus University of Budapest , Menesi út 45, H-1118 Budapest , Hungary.
authors.forename: László
authors.initials: L
authors.lastname: Narr
authors.affiliation: Faculty of Food Science, Department of Brewing and Distilling, Corvinus University of Budapest , Menesi út 45, H-1118 Budapest , Hungary.
authors.forename: Attila G
authors.initials: AG
authors.lastname: Kovács
authors.affiliation: Faculty of Food Science, Department of Brewing and Distilling, Corvinus University of Budapest , Menesi út 45, H-1118 Budapest , Hungary.
authors.forename: Gabriella
authors.initials: G
authors.lastname: Styevkó
mesh_terms: D004583:Electrons; D005290:Ferric Compounds / Q000378:metabolism; D005650:Fumarates / Q000378:metabolism; D045302:Geobacter / Q000737:chemistry / Q000254:growth & development* / Q000378:metabolism*; D007700:Kinetics
chemical_list: D005290:Ferric Compounds; D005650:Fumarates
keywords: Geobacter toluenoxydans; iron-reduction; microbial fuel cell