title: Kinetic modeling of poly(beta-hydroxybutyrate) production and consumption by Paracoccus pantotrophus under dynamic substrate supply.
abstract: The objective of the research was to obtain insights into the behavior of microorganisms under feast/famine conditions as often occur in wastewater treatment processes. The response of microorganisms to such conditions is the accumulation of storage polymers like poly(beta-hydroxybutyrate). The research was performed using a pure culture of Paracoccus pantotrophus LMD 94.21. A steady-state C-limited chemostat culture was switched to batch mode and a pulse of acetate was added. As long as external substrate (acetic acid) was present, the organism grew and accumulated poly(beta-hydroxybutyrate). After depletion of the external substrate, the stored poly(beta-hydroxybutyrate) was used as growth substrate. Poly(beta-hydroxybutyrate) accumulation was found to be strongly dependent on the growth rate of the organism before the pulse addition of acetate. Poly(beta-hydroxybutyrate) accumulation was correlated to the difference in maximum acetate uptake rate and the acetate required for growth. Based on the interpretation of the experimental results, a metabolically structured model has been set up. This model adequately describes the observed kinetics of the poly(beta-hydroxybutyrate) formation and consumption. (c) 1997 John Wiley & Sons, Inc. Biotechnol Bioeng 55: 773-782, 1997.
authors.affiliation: Delft University of Technology, Kluyver Laboratory for Biotechnology, Department of Biochemical Engineering, Julianalaan 67, NL-2628 BC Delft, The Netherlands. mark.vl@stm.tudelft.nl
authors.forename: M A
authors.initials: MA
authors.lastname: van Aalst-van Leeuwen
authors.forename: M A
authors.initials: MA
authors.lastname: Pot
authors.forename: M C
authors.initials: MC
authors.lastname: van Loosdrecht
authors.forename: J J
authors.initials: JJ
authors.lastname: Heijnen