National & World News
Microbes from the guts of cows can break down plastic
by Brooks Hays
Washington DC (UPI) Jul 2, 2021
Microbes found in a cow's stomach can breakdown plastics, according to new research.
Researchers found the polymer-munching microbes in the rumen, one of four compartments
comprising the bovine stomach. The bacteria, described Friday in the journal Frontiers in
Bioengineering and Biotechnology, could be used to reduce plastic litter in landfills and polluted ecosystems. The discovery wasn't entirely unexpected, as the diet of cows and other ruminants features a significant amount of natural plant polyesters.
Scientists figured the bacteria could probably break down synthetic plastics, too, which
are similar in their construction and chemical composition.
"A huge microbial community lives in the rumen reticulum and is responsible for the
digestion of food in the animals," study co-author Doris Ribitsch said in a press release.
"So we suspected that some biological activities could also be used for polyester
hydrolysis," said Ribitsch, a researcher at the University of Natural Resources and Life
Sciences in Vienna, Austria.
In the lab, researchers exposed three different types of plastics to the cow rumen-
First, scientists fed the bacteria polyethylene terephthalate, or PET, a synthetic polymer
used in textiles and packaging.
Researchers also tested polybutylene adipate terephthalate, PBAT, a biodegradable
plastic used to make plastic bags, and and bio-based polymer material called
The microbes living in the rumen liquid successfully broke down all three plastics much
more efficiently than previously tested bacteria strains, suggesting a synergistic
advantage among the community of microbes living in a cow's stomach.
These microbes likely produce not one, but a multitude of enzymes capable of breaking
"Due to the large amount of rumen that accumulates every day in slaughterhouses,
upscaling would be easy to imagine," Ribitsch said.
Ribitsch and her colleagues plan to continue testing the plastic-eating abilities of
"Despite the fact that rumen fluid could be a cheap source for polymer-degrading
enzymes, future studies should aim at identification and cultivation of the microbes and
enzymes," researchers wrote.