Fantastic Fungi
1. How Fungi Break Down Plastic
Fungi degrade plastic through makeshift chemical and physical mechanisms. They produce a suite of extracellular enzymes—such as laccases, peroxidases, hydrolases, cutinases, lipases, and proteases—which fragment high‑molecular‑weight polymers into smaller molecules like oligomers and monomers. These are then assimilated as carbon and energy sources through processes called biodeterioration, depolymerization, assimilation, and mineralization
Their mycelia physically penetrate plastic surfaces, improving contact and accelerating breakdown.
2. Known Species & Degradation Rates
Over 400 microbial species, including more than 100 fungi, have been identified that can break down plastics
Pestalotiopsis microspora, discovered in the Ecuadorian Amazon, can digest polyurethane—even under low-oxygen (anaerobic) conditions like landfills
A study by Australian researchers showed Aspergillus terreus (and Engyodontium album) could degrade polypropylene—making up 25–27% of samples in just 90 days and achieving complete breakdown in ~140 days in lab settings—the fastest known rate so far
Actinomucor elegans, when paired with Pseudomonas mendocina, synergistically degraded PLA/PBAT biodegradable plastics more effectively than fungi alone—via collaboration of lipases and proteases
3. Marine Fungi's Potential
Marine-derived fungal species such as Zalerion maritimum have been shown to biodegrade polyethylene in aquatic environments
Parengyodontium album, found in the Great Pacific Garbage Patch, colonizes floating plastic and degrades polyethylene at around 0.05% per day, particularly when plastics have been UV-exposed—suggesting a role in surface-layer plastic decay
4. Emerging Real-World Applications
A German study found freshwater fungi that can survive on and degrade synthetic plastics as their sole carbon source, offering promise for aquatic bioremediation—although efficiency varies by pollutant type and conditions
Hiro Technologies, based in Austin, TX, sells fungi-embedded diapers that deploy plastic-eating fungi to degrade diaper plastics into soil-like matter within about nine months under lab conditions. The approach builds on work showing fungi like P. microspora can tackle polyurethane in anaerobic conditions
5. Limitations & Challenges
Most research has been conducted in controlled lab settings, and real-world conditions—like temperature, humidity, UV exposure, and microbial competition—can reduce effectiveness.
Not all plastics respond similarly: polyurethanes are more readily degraded; polyethylene and microplastics(especially with additives) remain more resistant.
Scale-up challenges include managing conditions, targeting specific plastic types, ensuring safety (e.g. no toxic byproducts), and integrating fungal systems into existing waste processes.
