Superworms are beetle larvae that look like giant mealworms and are typically sold in pet shops as food for fish, birds, and reptiles. However, these worms are far more significant than just ordinary pet food, as they can consume and break down polystyrene plastic. Now, South Korean scientists are looking into the possibility of superworms aiding in the reduction of plastic pollution.
While plastic takes several hundred years to decompose, superworms and mealworms have been found to ingest and break down polystyrene within a few weeks. After analyzing the worms, scientists Jiaojie Li and Dae-Hwan Kim have linked their ability to eat polystyrene to a bacteria strain that lives within the larvae’s gut.
For the study, the team put fifty superworms in a chamber with plastic as their only source of carbon. After twenty-one days, the worms had consumed roughly 70% of the polystyrene. Then, the researchers isolated a strain of Pseudomonas aeruginosa bacteria from the worm’s gut and demonstrated that it could grow on the surface of the plastic and break it down.
They found that an enzyme from the bacteria, known as serine hydrolase, was responsible for most of the biodegradation. The team believes that either this enzyme or the bacteria that produce it could eventually be used to help break down plastic waste.
Scientists have previously discovered larvae eating plastic. In 2017, researchers found that honeycomb moth larvae also consume polyethylene. This is something natural to the species as they usually eat honeycomb wax, which has similar compounds to plastic.
In 2015, Stanford University scientists discovered that mealworms could be employed to break down Styrofoam (polystyrene) waste. The insects eat the material and break it down through digestion. Since then, the team has found that the worms do not absorb the toxic substance in the foam (hexabromocyclododecane, aka HBCD) into their bodies. Meaning, the bugs are safe to eat! They can be used to help with the problem of Styrofoam waste and then livestock feed.
