This Tiny Caterpillar Could Help Solve the World's Plastic Crisis
A research team discovered that the caterpillars of the greater wax moth—considered a pest in Europe because it eats the beeswax from honeycombs—also has the ability to biodegrade polyethylene, the same material used in whale-choking, landfill-clogging plastic shopping bags.
Incredibly, this discovery was all down to chance.
Scientist and amateur beekeeper Federica Bertocchini of Spain's IBBTEC institute had picked out a number of the parasitic caterpillars from her beehives and placed them into a plastic bag. She later discovered that the bag was full of holes because the waxworms had eaten their way out.
She decided to study the caterpillars further, enlisting researchers from the University of Cambridge's department of biochemistry to find out how good these little bugs were at eating plastic.
For their study, the team exposed around a hundred wax worms to a plastic bag from a UK supermarket. Remarkably, holes started to appear after just 40 minutes. After 12 hours, there was a reduction in plastic mass of 92 milligrams from the bag.
To test whether it was just the chewing mechanism of the caterpillars degrading the plastic, the team then mashed up some of the worms and smeared the paste onto polyethylene bags. The bags also degraded with similar results.
This implies that the chemicals in the caterpillar's body could be responsible for breaking down polyethylene.
"The caterpillar produces something that breaks the chemical bond, perhaps in its salivary glands or a symbiotic bacteria in its gut," Cambridge's Paolo Bombelli, first author of the study, said. "The next steps for us will be to try and identify the molecular processes in this reaction and see if we can isolate the enzyme responsible."
The team published their study in the journal Current Biology.
"If a single enzyme is responsible for this chemical process, its reproduction on a large scale using biotechnological methods should be achievable," Bombelli said.
Largely utilized in packaging, polyethylene represents about 40 percent of total demand for plastic products, including the trillion plastic bags used every year worldwide. As Bombelli said, "this discovery could be an important tool for helping to get rid of the polyethylene plastic waste accumulated in landfill sites and oceans."