Researchers at the University of Edinburgh genetically reprogrammed E. coli to convert plastic into paracetamol, which is also known as acetaminophen (Tylenol). They published their findings in Nature Chemistry. The process could cut down on plastic waste while reducing emissions from traditional methods of creating paracetamol.
A Ph.D. student checks the growth of a culture of E. coli in the Wallace Lab. Image from Edinburgh University.
Using bacteria to recycle plastic
Polyethylene terephthalate (PET) is a plastic used to make water bottles and food containers that creates more than 350 million tons of waste per year. The researchers broke PET down into terephthalic acid, which is then transformed into acyl hydroxamate. Then the modified E. coli uses the acyl hydroxamate in a Lossen rearrangement inside its cells. This rearrangement turns acyl hydroxamate into para-aminobenzoic acid (PABA). The E. coli created by the researchers is genetically modified to turn PABA, which it usually uses for growth, into paracetamol.
The process has a 92% yield of paracetamol. CO2 is the only byproduct of the reaction. The team was also able to show that the process is compatible with mixed plastic sources.
Traditional paracetamol synthesis
Paracetamol is traditionally made from phenol, a compound derived from crude oil. This process requires high temperatures and pressures as well as hazardous reagents. According to Open Access news, thousands of tons of fossil fuels are used annually to power the factories that produce paracetamol.
The new method not only cuts down on plastic waste by using it to create a usable material, but also produces virtually no carbon emissions. The new reaction occurs at room temperature and uses plastic rather than crude oil as a source material.
