abstract
In this work, hardwood spent sulfite liquor (HSSL), a complex feedstock originating from the pulp industry, was tested for the first time as a substrate for polyhydroxyalkanoate (PHA) production by a mixed microbial culture (MMC) under aerobic dynamic feeding (ADF) conditions. A sequencing batch reactor (SBR) fed with HSSL was operated for 67 days and the selected MMC reached a maximum PHA content of 67.6%. The MMC demonstrated a differential utilization of the carbon sources present in HSSL. Acetic acid was fully consumed, while xylose and lignosulphonates were partially consumed (30% and 14%, respectively). The selected culture was characterized by Fluorescence in Situ Hybridization (FISH). Bacteria belonging to the three main classes were identified: Alpha-(72.7 +/- 4.0%), Beta-(11.1 +/- 0.37%) and Gammaproteobacteria (10.3 +/- 0.3%). Within Alphaproteobacteria, a small amount of Paracoccus (4.2 +/- 0.51%) and Defluvicoccus related to Tetrad Forming Organisms (9.0 +/- 0.28%) were detected. (C) 2014 Elsevier Ltd. All rights reserved.
keywords
POLY-BETA-HYDROXYBUTYRATE; SPENT SULFITE LIQUORS; POLYHYDROXYBUTYRATE PRODUCTION; MICROBIAL CULTURE; POLYHYDROXYALKANOATES; COMMUNITY; OXIDATION; MOLASSES; REACTOR; OXYGEN
subject category
Agriculture; Biotechnology & Applied Microbiology; Energy & Fuels
authors
Queiros, D; Rossetti, S; Serafim, LS
our authors
Diogo Cerqueira Queirós
PhD Student
Luísa Seuanes Serafim
Assistant Professoracknowledgements
This work was funded by FEDER Funds through the Programa Operacional Factores de Competitividade - COMPETE and national funds through FCT - Fundacao para a Ciencia e a Tecnologia under the project PEST-C/CTM/LA/0011/2011. Authors acknowledge Eng. A. Prates from CAIMA, Industria de Celulose S.A., Constancia, Portugal for HSSL, Prof. Dmitry V. Evtuguin and Prof. Ana M.B.R. Xavier, from CICECO/University of Aveiro, for expertise regarding HSSL, and Dr. Paulo C. Lemos from CQFB/REQUIMTE, FCT/UNL for GC analysis. D. Queiros thanks FCT for his PhD grant (SFRH/BD/87758/2012).