Researchers at the University of Queensland have discovered the common Zophobas morio ‘superworm’ can eat through polystyrene, thanks to a bacterial enzyme in their gut. This could be the key to plastic recycling on a mass scale.

Dr Chris Rinke and his team from UQ’s School of Chemistry and Molecular Biosciences fed superworms different diets over a three week period, with some given polystyrene foam, some bran and others put on a fasting diet.

The Zophobas morio ‘superworm’ can eat through polystyrene. 

“We found the superworms fed a diet of just polystyrene not only survived, but even had marginal weight gains,” Dr Chris Rinke said. “This suggests the worms can derive energy from the polystyrene, most likely with the help of their gut microbes.”

The researchers used a technique called metagenomics to find several encoded enzymes with the ability to degrade polystyrene and styrene.

Dr Chris Rinke from University of Queensland.

The long-term goal is to engineer enzymes to degrade plastic waste in recycling plants through mechanical shredding, followed by enzymatic biodegradation.

“Superworms are like mini recycling plants, shredding the polystyrene with their mouths and then feeding it to the bacteria in their gut,” Dr Chris Rinke continued. “The breakdown products from this reaction can then be used by other microbes to create high-value compounds such as bioplastics.”

Co-author of the research, PhD candidate Jiarui Sun, said they aim to grow the gut bacteria in the lab and further test its ability to degrade polystyrene. It is hoped this bio-upcycling will incentivise plastic waste recycling and reduce landfill.

“We can then look into how we can upscale this process to a level required for an entire recycling plant,” Jiarui Sun shared.