The approach harnesses the power of bacteria to transform post-consumer plastic into L-DOPA, a frontline medication for the neurological disorder.
It is the first time a natural, biological process has been engineered to turn plastic waste into a therapeutic for a neurological disease, researchers say.
Engineered bacteria
Scientists at the university engineered E. coli bacteria to turn a type of plastic used widely in food and drink packaging – polyethylene terephthalate, or PET – into L-DOPA.
The process involves first breaking down PET waste – some 50 million tonnes of which are produced annually – into chemical building blocks of terephthalic acid.
Molecules of terephthalic acid are then transformed into L-DOPA by the engineered bacteria through a series of biological reactions.
Recycling processes
Using the new technique to produce L-DOPA is more sustainable than traditional methods of making pharmaceuticals, which rely on the use of finite fossil fuels, the team says.
There is an urgent need for new methods to recycle PET, a strong, lightweight plastic derived from non-renewable materials such as oil and gas, the team says.
Existing recycling processes are not completely efficient and still contribute to plastic pollution worldwide.
The advance offers a sustainable way of repurposing valuable carbon in plastic waste that would otherwise be lost to landfill, incineration or environmental pollution, the team says.
It could pave the way for growth of a bio-upcycling industry for producing not only pharmaceuticals but a wide range of products including flavourings, fragrances, cosmetics, and industrial chemicals, they add.
Industrial application
Having now demonstrated the production and isolation of L-DOPA at a preparative scale, the team will next focus on advancing the technology towards industrial application.
This will involve further optimising the process, improving its scalability, and further assessing its environmental and economic performance, the team says.
Sustainable manufacturing
The research was carried out at a pioneering new hub that aims to help transform UK manufacturing by converting industrial waste into valuable, sustainable chemicals and materials.
The £14 million Carbon-Loop Sustainable Biomanufacturing Hub (C-Loop) is supported by the Engineering and Physical Sciences Research Council (EPSRC), part of UKRI.
This research shows the huge potential of engineering biology to tackle some of society’s most pressing challenges,” said Professor Charlotte DeaneEPSRC Executive Chair, UKR.
“By converting discarded plastic into a treatment for Parkinson’s disease, the University of Edinburgh team has demonstrated how carbon that would otherwise be lost to landfill or pollution can be turned into high-value products that improve lives.
“It’s a great example of how EPSRC’s investment in C-Loop is enabling innovative, sustainable manufacturing approaches that benefit both people and the planet.
The findings are published in the journal Nature Sustainability. It was funded by UK Research and Innovation (UKRI) and the Industrial Biotechnology Innovation Centre (IBioIC), with test lab and innovation centre Impact Solutions as an industry partner.
“This feels like just the beginning,” said Professor Stephen Wallace School of Biological Sciences.
“If we can create medicines for neurological disease from a waste plastic bottle, it’s exciting to imagine what else this technology could achieve.
“Plastic waste is often seen as an environmental problem, but it also represents a vast, untapped source of carbon.
“By engineering biology to transform plastic into an essential medicine, we show how waste materials can be reimagined as valuable resources that support human health.”