Bacteria biodegrades polyethylene

08-Dec-14

Strains of bacteria found in waxworms, a type of moth caterpillar, can break down polyethylene (PE) plastic, according to new research from a team of US and Chinese researchers. Researchers at Beihang University and Shenzhen Key Laboratory of Bioenergy in China, and Stanford University in the US, led by Beihang’s Jun Yang, say that their discovery could lead to new methods to tackle the growing polyethylene waste problem. The team wanted to find a one-step method to degrade PE. The waxworm is the caterpillar of the moth Plodia interpunctella, which is known to eat plastic. The researchers isolated bacteria from the worms’ digestive system to identify which was responsible for breaking down the plastic. They incubated films of the bacteria on samples of PE for 28 days. They examined the PE using scanning electron microscopy (SEM) and atomic force microscopy (AFM). Two strains of bacteria, Enterobacter asburiae YT1 and Bacillus sp. YP1, were shown to break down the plastic. The surface of the PE was covered in pits and cavities. They also tested the strains in suspension for 60 days with PE samples and detected break-down products in the solution.