Plastics No More

The central question to this project is: How can the PHA production cycle be optimized with help from biological techniques.

Waste-plastics are a big, world-wide problem and cause a lot of damage to the environment and our health. That is why it is important to produce high quality, sustainable plastics. However, the production of sustainable plastics – and specifically PHAs made by micro-organisms – is expensive compared to conventional plastics. The high costs are due to a relatively low yield, slow microbial growth, and complicated extraction and generation of PHAs from the micro-organisms. That is exactly why production- and cleaning-methods for PHAs need to be improved before continually high-quality PHAs can be produced up to the quantity and quality that the market demands.

The goal of this project is to produce PHAs in a way that is fully sustainable and economically viable, while also meeting the criteria and adhering to the necessary properties for the application in various scenarios. This way, PHAs become serious competition for conventional plastics.

The doctoral research leads to increased knowledge about the production process of PHA. This results in several partial outcomes:

• Expanding the database of the project Circular Biopolymer Value Chains with biological production data. To be able to anticipate future demand for specific PHAs, the influence of various conditions on PHA production and PHA composition is being mapped.
• Developing an environmentally friendly alternative for the extraction and purification of PHA from bacterial cells. Currently, organic solvents and a lot of energy are required for this process. Research is being conducted into whether a greener alternative based on enzymatic extraction is possible.
• Designing bacterial strains that can release biopolymers from the cells through autolysis (self-destruction of the cell). It is being investigated whether PHAs can be extracted from the cell suspension using enzymes after the bacteria undergo autolysis.

Bioplastics have a lot of advantages compared to conventional, fossil plastics. First, fossil plastics cause a lot of waste, which in turn causes a lot of damage to our environment and health. Second, conventional plastics need fossil resources to be produced, these resources are getting scarcer, while the demand keeps growing. Lastly, bioplastics are biologically produced and degradable, which means it can be a part of a closed chain. The use of bioplastics contributes to the transition towards a circular, biobased economy.

Aside from these important advantages there is another benefit: specifying the properties in PHA is easier than in conventional plastics. Through enzymatic and chemical modification of PHAs, multiple functional groups of polymers can be produced. Examples of this are antibiotics, or molecules that control the reaction of water of polymers.

Since knowledge about PHAs is limited, Hanze UAS has the opportunity to make a big difference for the large scale application of PHAs. If consistency and quality can be safeguarded, Hanze UAS will be the first organization that can deliver this to the market.

Noëlle is getting her doctorate under Prof. Dr. Gert-Jan Euverink, professor Biotechnology and Biobased Products at the University of Groningen (RUG). The knowledge and publications resulting from this project adhere to the research that is being executed by the RUG. The fundamental work of the RUG will be applied in practice by the research done by Hanze UAS. This way, the hole between fundamental findings and practice is closed, making sure that the ideas are also translated into applicable real-life scenarios.

Moreover, practice-oriented research in turn creates new questions for fundamental researchers. Knowledge and experiences from the work-field can be used for follow-up research from universities or other knowledge-institutions.