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Cow Stomach Enzymes Found to Break Down Common Plastics

The all-natural breakthrough could have widespread environmental impacts by reducing plastic waste.

(CN) --- Plastics touch every aspect of our modern lives, containing and comprising many of the products we depend on every day. Because they’re hard to break down, plastics also poison the planet we depend on for life.

Hoping to solve this dilemma, researchers in Austria have discovered that bacteria from a cow’s stomach can digest certain types of plastics --- a breakthrough that could save the planet by reducing plastic waste.

The bacteria in question is found in a cow’s rumen, one of four compartments in its stomach. Since a cow’s diet contains natural plant polyesters, researchers suspected the bacteria a cow uses to break down this diet might have wider uses.

“We suspected that some biological activities could also be used for polyester hydrolysis,” said Dr. Doris Ribitsch of the University of Natural Resources and Life Sciences in Vienna.

Hydrolysis is a type of chemical reaction that causes decomposition. Because microorganisms in this natural process already break down similar materials, scientists suspected they might be able to break down plastics as well.

To test their theory, researchers examined three kinds of polyesters: polyethylene terephthalate, a synthetic polymer known as PET that is commonly used in textiles and packaging; polybutylene adipate terephthalate (PBAT) a biodegradable plastic often used in compostable plastic bags; and polyethylene furanoate (PEF) a biobased material made from renewable resources.

After obtaining rumen liquid from a slaughterhouse in Austria, researchers incubated that liquid with the three types of plastics they were testing.

The results, published Thursday in the journal Frontiers in Bioengineering and Biotechnology, were profound. All three plastics could be broken down by the microorganisms from cow stomachs.

Compared to similar research on single microorganisms, Ribitsch and her colleagues found that the rumen liquid was more effective. This indicates indicate the rumen’s enzyme combination is more potent than any single enzyme.

The implications of this research could profoundly affect the future. Because plastics don’t naturally decompose, they threaten wildlife and continue to spread toxins throughout their existence. They also contribute to global warming because almost all plastics are made from chemicals that come from the production of planet-warming fossil fuels. A natural process to break down plastics could limit these problems.

While Ribitsch’s research has only been conducted in a lab, she’s confident the results could easily be upscaled.

“Due to the large amount of rumen that accumulates every day in slaughterhouses, upscaling would be easy to imagine,” she stated.

However, such research is currently expensive, making its widespread use daunting at present. Despite this, Ribitsch intends to continue researching the topic, noting that microbial communities have been underexplored as a potential eco-friendly resource.

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