Chemists have discovered that Escherichia coli, better known as E. coli, can transform a molecule obtained from polyethylene terephthalate (PET) plastic into painkillers.
Almost all the plastic used in everyday life is derived from fossil fuels, and only a small portion is recycled. Paracetamol is derived from benzene, which is a really unsustainable petrochemical that also emits dangerous amounts of greenhouse gases into the atmosphere. The vast majority of plastic waste ends up in unwanted places like landfills or even in the oceans, harming life on land and in the water. A discovery by researchers into turning plastic waste into painkillers could turn the problem of plastic waste into something useful. Managing amounts of waste (like plastics or agricultural byproducts) and the need for more sustainable chemical manufacturing are the two problems this process of manufacturing painkillers aims to address.
This research was headed by Professor Stephen Wallace from the University of Edinburgh. When speaking on the research, Professor Wallace noted, “What this technology shows is that by merging chemistry and biology in this way for the first time, we can make paracetamol more sustainably and clean up plastic waste from the environment at the same time.”
Wallace and his colleagues discovered how a Lossen rearrangement, a type of chemical reaction, was biocompatible, meaning it was not a toxic process to living cells. It could be carried out without harming the living cells. The team discovered the process’s biocompatibility when they took PET, a type of plastic found in food packaging and bottles, and used sustainable chemical methods to convert PET into a new material. They incubated PET with a harmless strain of E. coli and later found that this was converted into a substance known as PABA. The researchers say the results are exciting as they suggest plastic waste can be converted into biological material. The researchers are in high spirits since, by using this form of E. coli, they were able to convert the PET-based starting material into paracetamol in under 24 hours, with low emissions and a yield of up to 92%, making the process both environmentally friendly and efficient.
“It enables, for the first time, a pathway from plastic waste to paracetamol, which is not possible using biology alone, and it’s not possible using chemistry alone,” Wallace said. The emissions from this new process “are fractional” compared with those from the current paracetamol manufacturing process, Wallace said. However, Wallace said this breakthrough is a step in the right direction in terms of sustainability. He said he sees plastic waste as an untapped resource that can be transformed into something useful, though it will take time.
This solution, utilising bacteria, is potentially cheaper, cleaner, and uses renewable materials, and this will help reduce the pharmaceutical industry’s carbon footprint, leading to headway in terms of the implementation of the process at commercial levels. Professor Stephen Wallace noted, “It’s going to be a while until you can go to the bar and get your beer in a plastic cup, take it home, put a bacterium in it and turn it into your hangover cure the next day.”
From the disposal bin to the medicine cabinet, these tiny bacterial factories are demonstrating that the future of medicine might just be found in the things we currently throw away.