Polypropylene, one of the most commonly used plastics in the world, poses a global environmental problem due to the problems associated with its recycling. Researchers have developed a new way to break down this pesky plastic with the help of some common fungi.
Most plastics do not break down easily and take decades to biodegrade, polluting terrestrial and marine ecosystems. One of these plastics, polypropylene (PP), is used in everything from plastic packaging to furniture to toys. But when it comes to plastic waste, PP is overrepresented.
PP collected on the street tends to be disposed of in landfills without being separated when it reaches a recycling facility, mainly because it has a short life as a packaging material and is easily mixed with other plastics. In 2015, the world produced 75 million tons (68 million tons) of PP, of which only 1% was recycled.
But help may be at hand, thanks to a new recycling technique developed by researchers at the University of Sydney with the help of unpretentious fungi.
“Plastic pollution is one of the biggest waste problems of our time,” said Amira Farzana Samat, lead author of the study. “Much of it is not properly recycled, so it often ends up in oceans, rivers and landfills. tonnes (33 million tonnes) is estimated to exist in the world’s oceans.
Researchers focused on two fungi that are common in soil and plants. Aspergillus terreus and Enjodontium album.
“Fungi are incredibly versatile and are known to be able to degrade almost any substrate,” said study co-author Dee Carter. “This superpower is due to the production of powerful enzymes that are excreted and used to break down substrates into simpler molecules that can be absorbed by fungal cells.”
PP is pretreated with either UV light, heat, or Fenton’s reagent, an acidic solution of hydrogen peroxide and iron commonly used to oxidize contaminants.
We then applied the fungus to the treated PP in Petri dishes and analyzed the degree of degradation using a microscope. Researchers found that the fungi were able to degrade PP more effectively when pretreated with UV light or heat. Fungi processed PP relatively quickly, reducing by 21% in 30 days and 25% to 27% in 90 days.
“We need to support the development of disruptive recycling technologies that improve the circularity of plastics, especially those driven by biological processes like ours,” said the study’s corresponding author. Ali Abbas said. “It is important to note that we have not yet optimized the experimental conditions in our study, so there is plenty of room to further reduce this degradation time.”
Further studies are expected to confirm the biochemical processes underlying degradation by this fungus, but for now, researchers are trying to determine the efficiency of the degradation method before seeking investors with a view to commercialization. I am planning to raise it.
The study was published in a journal Degradation of NPJ materials.
Source: University of Sydney
