title: Survival of the fastest: Selective removal of the side population for enhanced PHA production in a mixed substrate enrichment.
abstract: The success of enriching PHA-producers in a feast/famine regime strongly depends on the substrate utilized. A distinction can be made between substrates that select for PHA-producers (e.g. volatile fatty acids) and substrates that select for growing organisms (e.g. methanol). In this study the feasibility of using such a mixed substrate was evaluated. A sedimentation step was introduced in the cycle after acetate depletion and the supernatant containing methanol was discharged. This process configuration resulted in an increased maximum PHA storage capacity of the biomass from 48wt% to 70wt%. A model based on the experimental results indicated that the length of the pre-settling period and the supernatant volume that is discharged play a significant role for the elimination of the side population. However, the kinetic properties of the two different populations determine the success of the proposed strategy.
authors.affiliation: Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands.
authors.forename: Emmanouela
authors.initials: E
authors.lastname: Korkakaki
authors.affiliation: Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands.
authors.forename: Mark C M
authors.initials: MC
authors.lastname: van Loosdrecht
authors.affiliation: Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands. Electronic address: R.Kleerebezem@tudelft.nl.
authors.forename: Robbert
authors.initials: R
authors.lastname: Kleerebezem
mesh_terms: D018533:Biomass; D019149:Bioreactors; D054813:Polyhydroxyalkanoates / Q000032:analysis / Q000096:biosynthesis / Q000378:metabolism
chemical_list: D054813:Polyhydroxyalkanoates
keywords: Feast/famine; Mixed microbial enrichments; Mixed substrate; Polyhydroxyalkanoates (PHA); Settling; Side population