Accidental Discovery of Plastic Digesting Enzyme Could Tackle Plastic Pollution
Scientists have discovered an enzyme that can digest certain types of plastic - which would otherwise take hundreds of years to break down in the natural environment - in a matter of days, and they discovered it by accident.
The enzyme is capable of returning polyethylene terephthalate, or PET, the compound used in the manufacture of plastic bottles, back into its original chemical components, potentially solving one of the world's most prevalent plastic-pollution related problems.
Teams of researchers from the UK's University of Portsmouth and the US Department of Energy’s National Renewable Energy Laboratory (NREL), were conducting experiments into a strain of bacteria that is thought to have evolved naturally at a plastic waste recycling centre in Japan.
During the process of analysing the enzyme produced by the bacteria, the scientists accidentally engineered a modified version that proved to be better at degrading the plastic than the original.
The 'mutant enzyme' may have significant implications in the struggle to combat plastic pollution. Even when plastic bottles are collected for recycling, there are limitations as to what can be produced through the process - tough fibres that can be used in carpets, for example - and some products cannot be recycled at all.
Should the process be replicated on an industrial scale, it would mean that plastic bottles could be recycled back into other products - including more plastic bottles. While this may not completely remove plastic from the environment, it would significantly reduce the amount of new plastic that would need to be created, as the world seeks to source sustainable alternatives.
Professor John McGeehan, Director of the Institute of Biological and Biomedical Sciences in the School of Biological Sciences at Portsmouth, said: 'Few could have predicted that since plastics became popular in the 1960s, huge plastic waste patches would be found floating in oceans, or washed up on once pristine beaches all over the world.
'We can all play a significant part in dealing with the plastic problem, but the scientific community who ultimately created these ‘wonder-materials’, must now use all the technology at their disposal to develop real solutions.'
As a result of the discovery, the teams hope that the research can be developed for use on an industrial scale.
'The engineering process is much the same as for enzymes currently being used in bio-washing detergents and in the manufacture of biofuels,' said Prof McGeehan. 'The technology exists and it’s well within the possibility that in the coming years we will see an industrially viable process to turn [plastics] back into their original building blocks so that they can be sustainably recycled.'