Summary: In a breakthrough for “bio-upcycling,” scientists have engineered a way to transform plastic waste into L-DOPA, the primary drug used to treat Parkinson’s disease.
By using engineered E. coli bacteria, the team successfully converted polyethylene terephthalate (PET)—the plastic used in common drink bottles—into a high-value therapeutic. This study marks the first time a biological process has been used to turn plastic pollution into a neurological medicine.
Key Facts
- The Process: PET plastic is broken down into its building block, terephthalic acid. Engineered E. coli then perform a series of biological reactions to transform those molecules into L-DOPA.
- Environmental Impact: Some 50 million tonnes of PET are produced annually. This method offers a way to “valorize” waste that would otherwise end up in landfills or oceans.
- Sustainability: Traditional pharmaceutical manufacturing relies on finite fossil fuels (oil and gas). Using plastic waste as a carbon source is a significantly more sustainable alternative.
- Beyond Medicine: The researchers suggest this “Carbon-Loop” technology could be scaled to produce fragrances, flavorings, cosmetics, and industrial chemicals from plastic.
- Next Steps: Having proved the concept at a preparative scale, the team is now focusing on industrial scalability and optimizing the environmental and economic performance of the process.
Source: University of Edinburgh
A drug to treat Parkinson’s disease can be made from waste plastic bottles using a pioneering method, a study shows.
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.
Scientists at the University of Edinburgh 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.
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.
Having now demonstrated the production and isolation of L-DOPA at 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.
The findings are published in the journal Nature Sustainability. The research 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.
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.
The research is supported by Edinburgh Innovations, the University of Edinburgh’s commercialisation service.
Dr Susan Bodie, Director of Innovation Development and Licensing at Edinburgh Innovations, said: “Professor Wallace is one of several pioneering researchers at the University using innovative and sustainable engineering biology techniques to valorise waste, including with industry partners as part of the new Carbon Loop Hub. These techniques could help bring about a green revolution in industrial manufacture in the UK and beyond, and we would urge companies interested in working with us to get in touch.”
Dr Liz Fletcher, Director of Impact and Deputy CEO at IBioIC, said: “This project highlights the potential of biology to reshape the way we think about waste.
“Turning plastic bottles into a Parkinson’s drug isn’t just a creative recycling idea, it’s a way of redesigning processes that work with nature to deliver real-world benefits.
“By demonstrating that a harmful material can be converted into something that improves human health, the team is proving that sustainable, high-value applications of biology are both practical and effective.”
Professor Charlotte Deane Executive Chair, UKRI EPSRC, said: “This research shows the huge potential of engineering biology to tackle some of society’s most pressing challenges.
“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.”
Professor Stephen Wallace, of the University of Edinburgh’s School of Biological Sciences, who led the study, said: “This feels like just the beginning. 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.”
Key Questions Answered:
A: Technically, yes—but not in the way you think. The bacteria don’t just “clean” the plastic; they use it as raw food to build entirely new molecules. By the time the process is finished, the material is chemically identical to L-DOPA produced by traditional methods. It’s a total molecular transformation.
A: Standard recycling often “downcycles” plastic into lower-quality materials that eventually still end up as waste. This method is “upcycling”—it takes a low-value pollutant and turns it into one of the most important and valuable medications in neurology.
A: Potentially. By using a “waste” material that costs almost nothing as the raw ingredient, and relying on biological fermentation instead of expensive, energy-intensive chemical synthesis, the long-term cost of production could drop significantly as the technology scales.
Editorial Notes:
- This article was edited by a Neuroscience News editor.
- Journal paper reviewed in full.
- Additional context added by our staff.
About this Parkinson’s disease research news
Author: Corin Campbell
Source: University of Edinburgh
Contact: Corin Campbell – University of Edinburgh
Image: The image is credited to Neuroscience News
Original Research: The findings will appear in Nature Sustainability

