resumo
BACKGROUNDThe development of sustainable industrial processes demands the recovery and transformation of their by-products. The production of polyhydroxyalkanoates (PHAs) by mixed microbial cultures (MMC) is one of the available routes. This study evaluated the possibility of applying a two-step PHAs production process using an industrial by-product, hardwood sulphite spent liquor (HSSL), as feedstock for a MMC. The first step consisted in the selection of PHAs-storing microorganisms using an aerobic dynamic feeding strategy followed by a second step, accumulation. RESULTSThe selected MMC, despite not being able to use the main carbon source of HSSL, lignosulphonates, revealed the capacity to consume acetate and xylose to accumulate poly(3-hydroxybutyrate-co-3-hydroxyvalerate) and glucose biopolymer. The maximum PHAs content was relatively low, 6.6%, with a maximum production yield of 0.49 C-mmol HA C-mmol S-1 during the selection stage. CONCLUSIONA MMC was able to adapt to HSSL by consuming acetate and xylose. The imposed operational conditions resulted in a partial selection of the culture, since only acetate-consuming organisms experienced a real feast/famine regime, resulting in low PHAs production. (c) 2015 Society of Chemical Industry
palavras-chave
MIXED MICROBIAL CULTURES; SEQUENCING BATCH REACTOR; MILL WASTE-WATER; ACTIVATED-SLUDGE; PHA PRODUCTION; BIODEGRADABLE POLYMERS; STRATEGIES; BIOSYNTHESIS; FEEDSTOCK; MOLASSES
categoria
Biotechnology & Applied Microbiology; Chemistry; Engineering
autores
Queiros, D; Fonseca, A; Lemos, PC; Serafim, LS
nossos autores
Alexandre Miguel Alves Fonseca
Estudante de doutoramento
Diogo Cerqueira Queirós
Estudante de doutoramento
Luísa Seuanes Serafim
Professor Auxiliaragradecimentos
This work was developed within the scope of the project CICECO-Aveiro Institute of Materials (Ref. FCT UID/CTM/50011/2013) and LAQV, REQUIMTE (Ref. FCT UID/QUI/50006/2013), financed by national funds through the FCT/MEC and when appropriate co-financed by FEDER under the PT2020 Partnership Agreement. Diogo Queiros thanks FCT for his PhD grant (SFRH/BD/87758/2012).