Plastic Recycling
Kalandjibo Balo, a 23-year-old woman who recycles plastic for a living, poses for a photograph at Akouedo dump in Abidjan, Ivory Coast February 25, 2016. Reuters/Thierry Gougnon

The discovery by scientists of a new bacteria that can eat plastic is timely because studies indicate that by 2025, there would be one tonne of plastic for every three tonnes of finfish caught in the oceans. A report by McKinsey & Co and Ocean Conservancy in January names five Asian nations as the top plastic polluters in waterways and estimates $5 billion (AUD$7.2 billion) is needed annually over the next decade to fund a waste-management infrastructure made up mostly of waste-pickers.

Japanese researchers believe they have the solution to this global problem, using a new bacteria, Ideonella sakaiensis 201-F6, which can break down PET, used to make a lot of plastic materials. It works by turning PET into MHET, another substance, and then uses an additional enzyme to turn MHET into the basic components of PET.

The bacteria also give the option of turning MHET into new PET material. Because the bacteria takes six weeks to eat through a thin layer of PET, scientists are seeking ways to speed up the process, reports Engadget. One step in that direction is to sequence the bacteria’s genome to build stronger and faster strains of Ideonella sakaiensis 201-F6.

Globally, more than 300 million tonnes of plastic are produced yearly, although not all end up disposed in waterways. Besides the new bacteria, researchers had previously discovered worms and microbe that can break down plastic, though it is not as effective as Ideonella sakaiensis 201-F6. Scientists also need to discover another way of destroying plastic that do not use PET.

Although there are some varieties of fungi, marine microbes and worms that break down various components of plastic, none degraded it as thoroughly as the newly discovered bacteria. While many scientists will see its discovery, published in the March 11 issue of Science, as a great achievement, Uwe Bornscheuer, biochemist at Greifswald University in Germany, who was not involved in the Japanese research, says it should be a new starting point for the research of other scientists.