Survival of the fastest: Selective removal of the side population for enhanced PHA production in a mixed substrate enrichment

Journal article (2016)

Authors

Mark C.M. van Loosdrecht BT/Environmental Biotechnology - AS
R. Kleerebezem BT/Environmental Biotechnology - AS
Research Group
BT/Environmental Biotechnology (AS) (TU Delft)
Settling Mixed microbial enrichments Polyhydroxyalkanoates (PHA) Feast/famine Mixed substrate Side population
More Info
expand_more

Published Date

01-09-2016

Language

English

Reuse Rights

Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons.

Faculty

Applied Sciences

Department

BT/Biotechnologie

Research Group

BT/Environmental Biotechnology

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 48 wt% to 70 wt%. 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.