30 Oct 2018 Story Ecosystems

Fungi research lifts lid on shy organisms that break down plastic

Could fungi help us deal with our plastic addiction? Scientists at London’s Kew Botanical Gardens think so. The first ever State of the World’s Fungi, produced by Kew Gardens and a team of around 100 scientists from 18 countries, reports that fungi successfully degrades polyurethane in a matter of weeks.

The plastic-busting potential was discovered last year by a team of scientists from China and Pakistan, who sought to isolate the fungi that were degrading polyurethane at a waste disposal site in Islamabad. The fungi were identified as aspergillus tubingensis and the scientists observed how it broke down bonds between the different polymers in weeks, rather than the decades it can take plastic to naturally disintegrate.

The breakthrough comes as people across the world question the throwaway consumerist culture that has swamped the world in a toxic tide of plastic that is killing marine life and polluting seas. Report authors argue that fungi deserve more specialist attention, saying further research into these oft-neglected organisms could provide answers to some of humanity’s greatest challenges. There may be as many as 3.8 million fungal species but only 144,000 of them have been named.

“There is this hidden, mysterious kingdom that is underpinning the majority of life on earth,” says Dr. Ilia Leitch, senior scientist at Kew Gardens. “We just don’t know enough about them… There are fungi inside plant cells and they can influence how resilient a plant is to climate change. There are all these different links and impacts that we just take for granted but we ignore them at our peril,” she says.

Leitch says other fungi and microorganisms are also being explored for their potential to break down other types of plastic. “By understanding how the fungi break down these bonds and what the optimal conditions are, you can then increase the speed at which they do it.”

Every year, at least 8 million tonnes of plastic end up in our oceans, sometimes breaking down into tiny microplastics that make their way into our food chain with, as yet, unknown effects. Through its Clean Seas campaign, UN Environment has mobilized governments, businesses and citizens to rethink how we produce, use and manage single-use plastics.

The Kew Gardens report showcases the kind of pioneering thought that will be at the heart of the fourth UN Environment Assembly to be held in March next year. The theme for the meeting is innovative solutions for environmental challenges and sustainable consumption and production. The motto is to Think Beyond and Live Within: to think beyond prevailing patterns and live within sustainable limits to tackle environmental challenges and assure a prosperous future.

The Kew Gardens report certainly seeks to think beyond what is known about fungi, organisms that digest their food externally by secreting enzymes into the environment and absorbing the dissolved organic matter back into their cells.

“The first message we wanted to get across is that there is a huge diversity (of fungi)… What is clear is that fungi play a really important role (in the functioning of ecosystems) and it is perhaps not inconceivable to say that the world would not function without fungi,” says Leitch.

As well as recycling nutrients and helping plants and crop grow efficiently, fungi provide us with compounds that produce antibiotics, statins for treating cholesterol and immunosuppressants.

Some fungi - endophytes and mycorrhizas -can help plants respond to stresses such as increased temperature and drought. Advances in their agricultural applications could translate into improved food security, environmental sustainability and increased production revenues.

Fungi themselves are also threatened by climate change, particularly temperature rises in high latitudes such as the Arctic. These changes are already affecting fungi reproduction, geographic distributions and activity, with possible knock-on effects for our ecosystems.

There is mounting evidence that climate change is affecting the geographic ranges of species and biodiversity in ways we don’t yet understand. “Species react differently to climate change, which disrupts the delicate interaction between them,” says Niklas Hagelberg, a UN Environment climate change and ecosystems expert. “This further complicates conservation; we need to quickly add climate change to our ecosystem management effort.”

One obstacle to further fungi research is research funding, which has become more restricted and targeted, while expertise in taxonomy of fungi - classification - is declining, Leitch says. “We don’t have the iconic giant panda image,” she says. “There are amazing fungi but in terms of our image, it’s tricky sometimes to sell them. But maybe we can do it by making people realize the potential role of fungi in beating these environmental challenges.”

Ahead of the United Nations Environment Assembly next March, UN Environment is urging people to Think Beyond and Live Within. Join the debate on social media and use #SolveDifferent to share your stories and see what others are doing to ensure a sustainable future for our planet.