Story at a glance
- Plastic waste presents a growing problem due to its detrimental effects on the natural world and human health.
- Researchers in Australia conducted an experiment with “superworms” revealing certain enzymes can break down polystyrene, the main component of styrofoam.
- Ongoing experiments aim to explore how this process might be upscaled, but the cheap costs of new plastic production pose a hurdle.
As more countries and corporations launch campaigns to tackle plastic waste in the natural environment, researchers remain in lockstep aiming to address the problem on both a macro and micro scale.
Now, after conducting experiments with so-called “superworms,” a team of investigators at the University of Queensland in Australia discovered the common Zophobas morio have a unique appetite for plastic, and may even transform recycling.
This is thanks to a bacterial enzyme in the worms’ gut capable of digesting polystyrene and styrene.
Based on the findings, researchers hope to one day engineer the enzyme for large-scale production and degrade waste in recycling plants.
Polystyrene, a form of plastic used to create everything from styrofoam to appliances, is one of the main contributors to microplastic waste, as it does not biodegrade and merely breaks into smaller pieces (microplastics) when discarded.
Researchers discovered the worms’ capabilities after feeding them different diets of polystyrene foam or bran over the course of 3 weeks. Other worms were put on a fasting diet.
Those put on a diet solely consisting of polystyrene had marginal weight gains compared with the fasting worms, suggesting “the worms can derive energy from the polystyrene, most likely with the help of their gut microbes,” said Dr Chris Rinke of the School of Chemistry and Molecular Biosciences at the University of Queensland in a statement.
Likening the worms to “mini recycling plants,” Dr Rinke explained how the organisms shred the polystyrene with their mouths, then feed it to their gut bacteria.
“The breakdown products from this reaction can then be used by other microbes to create high-value compounds such as bioplastics,” he added.
The team is working to grow the bacteria in a lab environment to identify which enzyme is most effective at degrading polystyrene and better understand how the process can be upscaled.
Past research has explored the role of fungi and bacteria in breaking down plastic waste but innovations like these may be difficult to implement on a wide scale due to the cheap production costs of new plastic, experts warned.