Scientists discovered a species of worm with an appetite for polystyrene. Read to know how their gut enzyme may be the answer to revolutionizing recycling plastic.
Superworms can munch through plastic waste
Scientists from the University of Queensland discovered that superworms, the larvae of Zophobas morio darkling beetles can eat and digest polystyrene. They grow up to two inches and are generally bread to feed reptiles and birds across the world.
“We confirmed that superworms can survive on a sole polystyrene diet, and even gain a small amount of weight — compared to a starvation control group — which suggests that the worms can gain energy from eating polystyrene,” stated Chris Rinke. Rinke is the lead author of the study.
Over three weeks, they fed superworms with various diets. Some were given styrofoam or polystyrene foam. While others were given bran or starved. The research reveals bran was superior when compared to polystyrene. However, larvae gained weight in barn and styrofoam diets unlike those dying following the starvation diet. “They are basically like eating machines. Superworms are like mini recycling plants, shredding the polystyrene with their mouths and then feeding it to the bacteria in their gut,” added Rinke. “This study goes a long way towards understanding how the bacteria in [the superworms’] gut do this at the molecular level,” stated Colin Jackson. Jackson is a researcher from Australian National University and was not a part of the study.
Why is this study revolutionary?
Polystyrene is a huge threat to the environment. In addition to being non-biodegradable, it may take over 500 years to decompose. During this time it sits in landfills and produces toxic pollutants that are contributing to global warming and ozone layer depletion. It can also leech chemicals into water bodies. The study can be used for providing agricultural biowaste or food waste to the super worms. “This could be a way to improve the health of the worms and to deal with a large amount of food waste in Western countries,” said Rinke.
While breeding more super worms is a possible idea, the study provides an alternate method for implementation in the real world. The study suggests the creation of recycling plants mimicking the action of the larvae. “Ultimately, we want to take the super worms out of the equation,” explained Rinke. The team is planning to identify efficient enzymes and enhance them through enzyme engineering. “The scale-up and translation of research like this is always a challenge, which is magnified in the area of plastics by the incredible scale of the problem and the economics in terms of how cheap new plastic is to produce,” explained Jackson.
According to the American Chemistry Council, in 2018 in the United States, 27.0 million tons of plastic ended up in landfills compared to just 3.1 million tons that were recycled. Worldwide, only 9% of plastic was recycled according to a recent OECD report.