PHAs from mixed cultures as biopolymers for biodegradable films and flowerpots for plant transport

• Autor(a) principal: Ramos, Marta Luísa Silva
• Data de Publicação: 2019
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10362/89764
• topic: Polyhydroxyalkanoates (PHAs); Biodegradability; Mixed microbial cultures (MMC); Pulp and paper wastes; Films and flowerpots; Circular economy; Domínio/Área Científica::Engenharia e Tecnologia::Outras Engenharias e Tecnologias

Polyhydroxyalkanoates (PHAs) are biodegradable bioplastics with potential for fossil-based plastics’ replacement, that can be produced by mixed microbial cultures (MMC) from wastes. In this thesis, the possibility of PHAs synthesis from pulp and paper wastes, for the production of films and flowerpots for plants transport, was assessed. The PHAs production by MMC was carried out in a 3-stage process. After selection of the residues able to produce volatile fatty acids, the acidogenic fermentation stage consisted in their fermentation in reactor under different operating conditions. In the PHAs accumulating MMC enrichment stage, a microbial community with good PHAs storing capacity was selected through the use of a feast and famine regime, being also analysed by fluorescence in situ hybridization (FISH). Finally, in the accumulation stage the enriched MMC was fed with fermented wastes from stage 1, aiming to reach its maximum PHAs accumulation capacity. The produced polymer was extracted and evaluated for use in films and flowerpots, together with two others produced by Bioeng group, with different monomers content and purity.