Microplastics and nanoplastics are tiny plastic particles formed as larger plastic products break down through abrasion, sunlight, waves and other environmental factors. Their growing presence in water has raised concerns about possible harm to aquatic life and ecosystems.
The researchers, led by Professor Hiroshi Moriwaki, tested the slime from nameko mushrooms, which are widely consumed in Japan and known for their slippery surface. The slime is rich in polysaccharides, especially pectin, a natural compound known for binding particles.
“We chose nameko mushrooms because they are inexpensive and widely available in Japan”, Moriwaki said. “Moreover, their slime is safe and non-toxic, which makes it a sustainable solution”.
The team prepared the slime solution by soaking and shaking the mushrooms in water for five minutes. They then combined it with a solution of iron ions to treat water contaminated with polystyrene particles.
Within minutes, the plastic particles began clumping together into visible fibrous flocs.
“Pectin in the slime forms a gel with iron ions, which helps bind plastic particles into removable flocs through Coulomb forces”, Moriwaki said.
The method removed 95.3% of microplastics measuring 1 micrometer and 87.4% of nanoplastics measuring about 100 nanometers. When the researchers used wastewater from washing nameko mushrooms, removal efficiency rose to 98.4%.
The authors said nameko slime offers a safe and practical alternative to conventional chemical flocculants. They added that the residue left after treatment is biodegradable, which could reduce the overall environmental impact and help speed up large-scale wastewater and water treatment.
(jh)
Source: PAP