TECH

Developed enzyme that "eats" plastic bottles
The natural version of the enzyme was identified a few years ago in Japan at a recycling center.By studying its structure, researchers at the University of British Portsmouth and the US Department of Energy's NREL Laboratory have been able to accidentally improve it.In their study, published Monday in the journal Proceedings of the Natural Academy of Sciences, they claim that the enzyme, Ideonella sakaiensis 201-F6, is able to digest polyethylene terephthalate, or PET, a thermoplastic polymer developed in the 1940s and currently used in millions of bottles and other containers. The enzyme also breaks down its biological substitute, polyethylene furandicarboxylate, or PEF.PET plastics can persist for hundreds of years in the environment and are one of the largest sources of pollution on a planetary level. PEFs, despite their biological origin, are also not biodegradable and also end up in the dumps around the world."We were hoping to determine its structure to aid in the creation of proteins but we ended up taking a step forward and accidentally developing an enzyme with a better performance in the digestion of these plastics," said NREL research director Gregg Beckham."Fortunate chance plays a key role in scientific research and our discovery is no exception," said Professor John McGeehan, director of the Institute of Biological and Biomedical Sciences at the Faculty of Biology Sciences in Portsmouth. "Although the improvement is modest, this unexpected finding suggests that it is possible to further improve these enzymes, bringing us closer to a recycling solution for the constantly growing pile of discarded plastics, "McGeehan said.
Researchers are now trying to further improve the enzyme so that it can be used industrially to fractionate plastics in record time.
The discovery opens the door to recycling solutions for millions of tonnes of plastic bottles made of PET and PEF, says the University of Portsmouth.
NREL underscores the urgency of the investigation, saying that every year eight million metric tons of oceans enter the oceans, including PET bottles, creating huge floating islands of waste.
"Experts estimate that by the year 2025 there will be, by mass, both plastic rubbish and fish in the oceans," says the NREL online site.

Source: RTP