Plastic-Eating Fungus

A fungus from the Amazon rainforest can break down polyurethane plastic without oxygen. It's the first organism discovered with this capability, and it can survive using plastic as its only food source.

Most plastic waste ends up deep in landfills where oxygen doesn't reach, precisely where this fungus thrives. Polyurethane persists for centuries in these environments. It's everywhere: mattresses, insulation foam, shoe soles, adhesives, car parts. Annual global plastic production exceeds 400 million tons. Less than 10% gets recycled.

Pestalotiopsis microspora was discovered in 2011 in Ecuador's Yasuní National Forest, isolated from plant stems. The endophytic fungus lives inside plant tissues without harming its host. Laboratory testing revealed its remarkable ability: it degrades plastic equally well with or without oxygen present.

The fungus secretes an enzyme that breaks apart the chemical bonds holding polyurethane together. In laboratory tests, concentrated enzyme extracts can completely break down polyurethane polymer in under an hour. The fungus also produces a second enzyme that degrades PET plastic, splitting it into simpler compounds the fungus then consumes as food.

What makes this significant? Other plastic-degrading organisms need oxygen to function. When tested without oxygen, fungi like Lasiodiplodia and Pleosporales slowed down or stopped working. P. microspora maintained the same performance. This ability to work without oxygen directly addresses the actual problem—plastic buried in oxygen-depleted landfill depths.

The enzyme production is adaptive. When the fungus grows in a basic environment with only plastic available, it ramps up enzyme output. These enzymes spread through the surrounding material, breaking down plastic well beyond where the fungus itself is growing. The enzyme breakdown converts long-lasting polymer into simple compounds the fungus uses as food.

This fungus offers a biological solution that works precisely where the problem exists, in oxygen-depleted landfills where an ever-increasing amount our plastic waste collects.

by Sam Knowlton, The Confluence |  Read more:

Image: uncredited

[ed. Always a good reason to preserve natural habitats - who knows what other plants have undiscovered special properties? See also: A fungus that eats polyurethane (Yale Magazine).]

***

AI Overview:

Q. How long does it take Pestalotiopsis microspora to eat plastic?

Pestalotiopsis microspora can degrade plastic in a matter of weeks to months, with experiments showing significant degradation in as little as two weeks and over 60% breakdown in six weeks under ideal conditions. The specific timeframe varies, with some sources noting a few months for complete digestion in certain projects.