Researchers at the University of Queensland, Australia, have discovered that a species of worm that eats polystyrene could hold the key to recycling plastic on a massive scale. As published in the journal Microbial Genomics’, they have found that the common ‘superworm’ (‘Zophobasmorio’) can eat polystyrene thanks to a bacterial enzyme in its intestine.
Dr. Chris Rinke and his team at UQ’s School of Chemistry and Molecular Biosciences fed the worms different diets over a period of 3 weeks: some were given Styrofoam, others bran, and others a diet of fast. “We found that superworms fed a Styrofoam diet not only survived, but even gained slightly in weight”, explains DrRinke in a statement. “This suggests that the worms can obtain energy from Styrofoam, 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. The long-term goal is to design enzymes to degrade plastic waste in recycling plants by mechanical grinding, followed by enzymatic biodegradation.
“The superworms are like mini-recycling stations, shredding Styrofoam with their mouths and giving it to bacteria in their gut”, explains Rinke. “The breakdown products of this reaction can be used by other microbes to create high-value compounds, such as bioplastics”.
This biocycling is expected to encourage the recycling of plastic waste and reduce landfills. Co-author of the research, doctoral candidate Jiarui Sun, said her goal is to grow the gut bacteria in the lab and further test their ability to degrade polystyrene.
“Next, we can look at how to scale this process up to the level needed for a full recycling plant,” says Sun. In this sense, Rinke believes that there are many opportunities for the biodegradation of plastic waste. “Our team is very excited about pushing the science to make it happen”, she says.