Polyhydroxyalkanoates (PHAs) form a highly promising class of bioplastics for the transition from fossil fuel-based plastics to bio-renewable and biodegradable plastics. Mixed microbial consortia (MMC) are known to be able to produce PHAs from organic waste streams. Knowledge of key-microbes and their characteristics in PHA-producing consortia is necessary for further process optimization and direction towards synthesis of specific types of PHAs. In this study, a PHA-producing mixed microbial consortium (MMC) from an industrial pilot plant was characterized and further enriched on acetate in a laboratory-scale selector with a working volume of 5 L. 16S-rDNA microbiological population analysis of both the industrial pilot plant and the 5 L selector revealed that the most dominant species within the population is Thauera aminoaromatica MZ1T, a Gram-negative beta-proteobacterium belonging to the order of the Rhodocyclales. The relative abundance of this Thauera species increased from 24 to 40% after two months of enrichment in the selector-system, indicating a competitive advantage, possibly due to the storage of a reserve material such as PHA. First experiments with T. aminoaromatica MZ1T showed multiple intracellular granules when grown in pure culture on a growth medium with a C:N ratio of 10:1 and acetate as a carbon source. Nuclear magnetic resonance (NMR) analyses upon extraction of PHA from the pure culture confirmed polyhydroxybutyrate production by T. aminoaromatica MZ1T.
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‘Ontwerpen met biobased plastics’ is de eindpublicatie van het project “Design Challenges with Biobased Plastics”. In dit onderzoeksproject deed de HvA, samen met diverse mkb-bedrijven onderzoek naar de kennis een tools die ontwerpers nodig hebben om biobased plastics, kunststoffen van hernieuwbare materialen, toe te passen. De publicatie gaat in op de kansen die biobased plastics bieden en biedt praktische tools, inspirerende voorbeelden en handreikingen die het ontwerpen met deze materialen makkelijker maken.
Plastic products are currently been critically reviewed due to the growing awareness on the related problems, such as the “plastic soup”. EU has introduced a ban for a number of single-use consumer products and fossil-based polymers coming in force in 2021. The list of banned products are expected to be extended, for example for single-use, non-compostable plastics in horticulture and agriculture. Therefore, it is crucial to develop sustainable, biodegradable alternatives. A significant amount of research has been performed on biobased polymers. However, plastics are made from a polymer mixed with other materials, additives, which are essential for the plastics production and performance. Development of biodegradable solutions for these additives is lacking, but is urgently needed. Biocarbon (Biochar), is a high-carbon, fine-grained residue that is produced through pyrolysis processes. This natural product is currently used to produce energy, but the recent research indicate that it has a great potential in enhancing biopolymer properties. The biocarbon-biopolymer composite could provide a much needed fully biodegradable solution. This would be especially interesting in agricultural and horticultural applications, since biocarbon has been found to be effective at retaining water and water-soluble nutrients and to increase micro-organism activity in soil. Biocarbon-biocomposite may also be used for other markets, where biodegradability is essential, including packaging and disposable consumer articles. The BioADD consortium consists of 9 industrial partners, a branch organization and 3 research partners. The partner companies form a complementary team, including biomass providers, pyrolysis technology manufacturers and companies producing products to the relevant markets of horticulture, agriculture and packaging. For each of the companies the successful result from the project will lead to concrete business opportunities. The support of Avans, University of Groningen and Eindhoven University of Technology is essential in developing the know-how and the first product development making the innovation possible.
Lectoraat Circular Plastics zoekt partners voor onderzoek naar de biologische kringloop van kunststoffen. Hierdoor is zij in contact gekomen met WUR en betrokken geraakt bij de NWO aanvraag ‘Microbial Recycling of Biodegradable Plastics’. Middels dit voorstel gaat een haalbaarheidsonderzoek uitgevoerd worden naar de organische fractie van kunststof verpakkingsafval voor bedrijven. Bij deze aanvraag zijn ChainCraft en Better Future Factory betrokken. De onderzoeksvraag is of de organische fractie van kunststof verpakkingsafval geschikt gemaakt kan worden voor het procedé van ChainCraft om vetzuren te maken e/o er biopolymeren uit de organische fractie gemaakt kunnen worden voor 3D printer toepassingen van Better Future Factory. De uitkomst van het onderzoek moet inzicht geven of waarde creëren uit de organische fractie voor ChainCraft en Better Future Factory haalbaar is.
It is known that several bacteria in sewage treatment plants can produce attractive quantities of biodegradable polymers within their cell walls (up to 80% of the cell weight). These polymers may consist of polyhydroxyalkanoates (PHA), a bioplastic which exhibits interesting characteristics like excellent biodegradation, low melting point and good environmental footprint. PHA bioplastics or PHBV are still quite expensive because cumbersome downstream processing steps of the PHAcontaining bacteria are needed before PHA can be applied in products. In this proposal, the consortium investigates the possibilities for eliminating these expensive and environmentally intensive purification steps, and as a result contribute to speeding up the up-take of PHA production of residual streams by the market. The objective of the project is to investigate the possibilities of direct extrusion of PHAcontaining bacteria and the application opportunities of the extruded PHA. The consortium of experienced partners (Paques Biomaterials, MAAN Group, Ecoras and CoEBBE) will investigate and test the extrusion of different types of PHA-containing biomass, and analyse the products on composition, appearance and mechanical properties. Moreover, the direct extrusion process will be evaluated and compared with conventional PHA extraction and subsequent extrusion. The expected result will be a proof of principle and provide an operational window for the application of direct extrusion with PHA-containing biomass produced using waste streams, either used as such or in blends with purified PHA. Both the opportunities of the direct extrusion process itself as well as the application opportunities of the extruded PHA will be mapped. If the new process leads to a cheaper, more environmentally friendly produced and applicable PHA, the proof of principle developed by the consortium could be the first step in a larger scale development that could help speeding up the implementation of the technology for PHA production from residual streams in the market.
