Polypropylene, a hard-to-recycle plastic, has successfully been biodegraded by two strains of fungi in a new experiment led by researchers at the University of Sydney.
Polypropylene has long been recycling's head scratching riddle. A common plastic used for a wide variety of products from packaging and toys to furnishing and fashion, it accounts for roughly 28% of the world's plastic waste, but only 1% of it is recycled.
Now, thanks to the efforts of researchers at the University of Sydney, the recalcitrant polymer may have met its match. Published April 14 in npj Materials Degradation, two common strains of fungi were used to successfully biodegrade polypropylene in a laboratory experiment.
Typically found in soil and plants, Aspergillus terreus and Engyodontium album were able to break down polypropylene after it had been pre-treated with either UV light or heat, reducing the plastic by 21% over 30 days of incubation, and by 25%–27% over 90 days.
"Polypropylene is a common plastic used to make a huge variety of everyday products like food containers, coat hangers and cling film, but it only has a recycling rate of only one percent, meaning it is overrepresented in plastic waste and pollution globally," said the study's lead author from the University of Sydney's School of Chemical and Biomolecular Engineering, Ph.D. student Amira Farzana Samat.
The plastic before (left) and after (right). Credit: University of Sydney