Scientists at the University of Hawai‘i at Mānoa have found marine fungi that can degrade plastic, presenting innovative solutions for mitigating oceanic plastic pollution. Some fungi can even be trained to speed up the degradation process.
Researchers at the University of Hawai‘i at Mānoa have found that several species of marine fungi have the impressive ability to degrade plastic. This breakthrough, led by Ronja Steinbach, who was a marine biology undergraduate student in the UH Mānoa College of Natural Science at the time, brings promising potential for addressing one of the most pressing environmental issues — plastic pollution in the ocean.
“Plastic in the environment today is extremely long-lived, and is nearly impossible to degrade using existing technologies,” Steinbach said in a news release. “Our research highlights marine fungi as a promising and largely untapped group to investigate for new ways to recycle and remove plastic from nature. Very few people study fungi in the ocean, and we estimated that fewer than 1% of marine fungi are currently described.”
Plastic waste, characterized for its durability and utility, presents significant environmental hazards. When exposed to sunlight, heat and physical force, plastics disintegrate into harmful microplastics.
These microplastics not only threaten marine ecosystems but can also attract and concentrate toxic chemicals, such as phthalates and bisphenol A. Furthermore, marine animals can ingest these plastics, leading to potential starvation through malnutrition.
Understanding the gravity of the situation, with roughly 625,000 garbage trucks worth of plastic entering the ocean annually, innovative solutions are vital.
Previous studies have shown that some bacteria and terrestrial fungi can degrade plastics, but the UH Mānoa team’s focus on marine fungi could spark a paradigm shift. These marine fungi were isolated from diverse marine environments around Hawai‘i, such as sand, seaweed, corals and sponges.
“Fungi possess a superpower for eating things that other organisms can’t digest (like wood, or chitin), so we tested the fungi in our collection for their ability to digest plastic,” added co-author Anthony Amend, a professor at UH Mānoa’s Pacific Biosciences Research Center who heads the lab where the research was conducted.
The researchers tested these fungi by placing them in small dishes filled with polyurethane — a common plastic used in various products. They observed whether and how quickly the fungi degraded the plastic. Remarkably, more than 60% of the fungi showcased some capacity to consume plastic and convert it into fungal biomass.
“We were shocked to find that more than 60% of the fungi we collected from the ocean had some ability to eat plastic and transform it into fungi,” Steinbach added. “We were also impressed to see how quickly fungi were able to adapt. It was very exciting to see that in just three months, a relatively short amount of time, some of the fungi were able to increase their feeding rates by as much as 15%.”
Given Hawai‘i’s proximity to the North Pacific Subtropical Gyre and the infamous Great Pacific Garbage Patch, the importance of this discovery cannot be overstated.
The UH Mānoa team is now extending their research to evaluate whether these fungi, and potentially others, can degrade different types of plastics, such as polyethylene and polyethylene terephthalate, which represent even larger sources of marine pollution.
The team’s future plans also involve examining the cellular and molecular mechanisms enabling these fungi to degrade plastic compounds.
Steinbach shared the team’s broader vision, adding: “We hope to collaborate with engineers, chemists and oceanographers who can leverage these findings into actual solutions to clean up our beaches and oceans.”
The findings, published in the journal Mycologia, open new avenues for potential large-scale biotechnological applications aimed at reducing plastic waste in marine environments. What once seemed an insurmountable challenge now hints at a promising solution rooted in nature itself.