title: Waste to resource: Converting paper mill wastewater to bioplastic.
abstract: In this study we investigated the feasibility of producing polyhydroxyalkanoate (PHA) by microbial enrichments on paper mill wastewater. The complete process includes (1) paper mill wastewater acidogenic fermentation in a simple batch process, (2) enrichment of a PHA-producing microbial community in a selector operated in sequencing batch mode with feast-famine regime, (3) Cellular PHA content maximization of the enrichment in an accumulator in fed-batch mode. The selective pressure required to establish a PHA-producing microbial enrichment, as derived from our previous research on synthetic medium, was validated using an agro-industrial waste stream in this study. The microbial enrichment obtained could accumulate maximum up to 77% PHA of cell dry weight within 5 h, which is currently the best result obtained on real agro-industrial waste streams, especially in terms of biomass specific efficiency. Biomass in this enrichment included both Plasticicumulans acidivorans, which was the main PHA producer, and a flanking population, which exhibited limited PHA-producing capacity. The fraction of P. acidivorans in the biomass was largely dependent on the fraction of volatile fatty acids in the total soluble COD in the wastewater after acidification. Based on this observation, one simple equation was proposed for predicting the PHA storage capacity of the enrichment. Moreover, some crucial bottlenecks that may impede the successful scaling-up of the process are discussed.
authors.affiliation: Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands. Electronic address: Y.Jiang@tudelft.nl.
authors.forename: Yang
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands. Electronic address: L.Marang@tudelft.nl.
authors.forename: Leonie
authors.initials: L
authors.lastname: Marang
authors.affiliation: Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands. Electronic address: J.Tamis@tudelft.nl.
authors.forename: Jelmer
authors.initials: J
authors.lastname: Tamis
authors.affiliation: Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands. Electronic address: M.C.M.vanLoosdrecht@tudelft.nl.
authors.forename: Mark C M
authors.initials: MCM
authors.lastname: van Loosdrecht
authors.affiliation: Paques BV, T. de Boerstraat 24, 8561 EL Balk, The Netherlands. Electronic address: H.Dijkman@paques.nl.
authors.forename: Henk
authors.initials: H
authors.lastname: Dijkman
authors.affiliation: Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands. Electronic address: R.Kleerebezem@tudelft.nl.
authors.forename: Robbert
authors.initials: R
authors.lastname: Kleerebezem
mesh_terms: D019149:Bioreactors / Q000382:microbiology; D007220:Industrial Waste; D010209:Paper; D054813:Polyhydroxyalkanoates / Q000378:metabolism; D062065:Wastewater
chemical_list: D007220:Industrial Waste; D054813:Polyhydroxyalkanoates; D062065:Wastewater