With 56 million tons of plastics produced annually, plastic pollution is a major problem. But scientists in Japan may have found a solution: Ideonella sakaiensis, a new bacteria that feeds on one of the world's most common plastics, polyethylene terephthalate, also known as PET or polyester.
"We have shared the possibility of biological recycling of plastic," said Shosuke Yoshida, lead author of the study from Kyoto University. "We want to develop this discovery into the application. This is the very first step."
PET is a clear plastic used in clothing, plastic bottles and food packaging. It is made from two simple compounds, but until now scientists have not been able to find an organism that can break it down.
Further analyses revealed the plastic-eating bacteria almost completely degraded low-quality plastic within six weeks. Researchers believe I. sakaiensis may have evolved enzymes specialized for breaking down PET in response to the high quantities of plastics that have accumulated in the environment over the past 70 years.
"If you put a bacteria in a situation where they've only got one food source to consume, over time they will adapt to do that," said Tracy Mincer, a researcher at Woods Hole Oceanographic Institution. "I think we are seeing how nature can surprise us and, in the end, the resiliency of nature itself."
It follows then that this bacteria could be used to improve current recycling methods and reduce plastic pollution in the environment. In theory, researchers could culture the bacteria and release them on the mounds of plastics occupying landfills. However, this probably won't be very effective in the field, as the bacteria chomps on plastic very slowly, despite the fast rate at which it grows.
But there might be hope. Yoshida believes the process can be sped up. For example, bacteria are often harnessed to ferment alcoholic products, while yeast is harnessed to bake bread.
"It's certainly a move in the right direction. Having an organism that seems to be capable of biodegrading these components directly will help us develop a bioremediation technology," concluded John Coates, a microbiologist at the University of California, Berkeley, who was not involved with the work.
The findings were recently published in the journal Science.
Last year, a team of scientists found mealworms that can eat between 34 and 39 milligrams of Styrofoam in a period of 24 hours.
