Czech scientists explore possibility of plastic-eating cyanobacteria tackling ocean waste

Ondřej Pěnčík

Scientists at Mendel University in Brno are exploring the possibility of using cyanobacteria to clean up plastic waste in the oceans. After special treatment, the photosynthetic microscopic organisms could break down micro-particles of plastic waste, which accumulates in so-called garbage patches in the oceans.

Garbage patches are large areas of the ocean where litter, fishing gear and other marine debris collects as a result of swirling ocean currents, which have been growing steadily since the mid-1980s.

There are currently five such patches infesting the world’s three largest oceans, covering an area roughly the size of Australia and presenting an ever-growing threat to marine wildlife.

Microplastics | Photo: © Will Rose,  Greenpeace

Scientists from the Faculty of Agronomy at Mendel University in Brno are currently exploring ways of disposing of the unwanted waste by using cyanobacteria, which are naturally abundant in ocean waters, especially among the marine debris.

Biologist Ondřej Pěnčík is part of the research team:

“Most people regard algae and cyanobacteria as something very harmful, but it is not true. Many of them are actually essential for the functioning of the ecosystem. Our research focuses on the cyanobacteria that can degrade plastic.”

Mr. Pěnčík and his colleagues are currently investigating whether cyanobacteria could be able to eat plastic waste in the oceans after undergoing genetic modification.

“The method involves transferring a gene normally found in a bacterium that lives in landfills into a cyanobacterium, using molecular biology methods. The modified cyanobacteria would then be introduced into the ocean, making it possible to degrade plastic waste.”

The method described by Mr. Pěnčík could be particularly helpful in cleaning the seas and oceans. However, since the use of genetic modification is legally problematic, his team is also exploring ways of using cyanobacteria in their natural form. Such method could be used for cleaning fresh water.

Some cyanobacteria, namely those with a specific slime layer, can do this in their natural form. The micro-particles of plastic waste simply sticks to their surface, explains Mr. Pěnčík:

Ondřej Pěnčík | Photo: Mendel University Brno

“By trapping them on top of each other, they literally form clumps, which makes them relatively easy to get out of the water by sedimentation. That leaves the water practically clean.”

The slimy cyanobacteria could be used for instance in wastewater treatment plants, where they could trap not only micro and nanoplastics but also other harmful substances, such as hormones and pesticides.

As Mr. Pěnčík points out, rivers are the source of up to 80 percent of plastic waste in the oceans. If the management of wastewater treatment plants, especially in third world countries, improves, it could have a significant effect on the overall situation in the oceans.

Another major advantage of this technology is that it is very cheap and simple, since cyanobacteria are not difficult to grow.

Authors: Ruth Fraňková , Barbora Kroutilíková
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