Polystyrene foam, commonly known as Styrofoam, is a commonly used plastic in packaging and insulation industry. However, recycling is extremely difficult, and most places do not accept collection for recycling. Many countries around the world and some states in the US have enacted a total or partial ban on polystyrene foam. However, it is still one of the most widely used plastics, several million tons are produced each year.

Researchers at the University of Queensland in Australia have discovered that a type of beetle larva can eat, and completely decompose Styrofoam, which is notoriously difficult to recycle. The larvae of the Zophobas morio beetle have enzymes in their intestines that can break down the polystyrene. Chris Rinke, senior lecturer in the School of Chemistry and Molecular Biosciences at the University of Queensland, said: “This larva is like a small recycling plant, chopping polystyrene with its mouth and then letting the bacteria in its intestine decompose”

New discovery: Beetle Larva can eat and decompose Styrofoam

Researchers at the University of Queensland conducted an experiment on these beetle larvae. They divided the larvae into three groups, each with a different diet: bran, polystyrene or nothing. The bran-fed larvae doubled in weight after a few weeks, those on the polystyrene diet gained some weight, while the starved larvae did not. This result shows that the larvae can use polystyrene as food.

To determine exactly which enzyme can break down polystyrene, the researchers decoded the genomes of all organisms in the larvae’s gut, through a technique called metagenomics. They will then redesign these enzymes, so that they work more efficiently. This data will be key to turning this natural process into a process that takes place on a large industrial scale.

Scientists have been searching for years for bacteria or insects that can help break down plastic. In 2015, Stanford University engineers reported that mealworms can survive on a diet high in polystyrene. Bacteria in the mealworm’s gut help break down the plastic. Several other research groups have also reported that certain insects, such as wax moths and Indian moth larvae, can also decompose polystyrene.

decompose Styrofoam