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Dark-coloured fungi devour radiation and convert it to fuel, offering applications from more efficient solar cells to feeding astronauts in space, researchers have found.
Their study, in the Public Library of Science journal PLoS ONE, says that may also explain why it feels so good to soak up the sun on the beach.
The fungi use the same compound as people do - melanin, the pigment that makes skin and truffles dark.
"Just as the pigment chlorophyll converts sunlight into chemical energy that allows green plants to live and grow, our research suggests that melanin can use a different portion of the electromagnetic spectrum - ionising radiation - to benefit the fungi containing it," said Ekaterina Dadachova, of the Albert Einstein College of Medicine in New York.
Arturo Casadevall, chairman of microbiology and immunology at Einstein, added: "It's pure speculation but not outside the realm of possibility that melanin could be providing energy to skin cells."
Their experiment was fairly simple.
Dr Casadevall was reading about fungi found growing in and around the reactor at Chernobyl, closed and heavily contaminated by an accident in 1986.
"It gave us the idea that maybe fungi use melanin to harness radiation."
So they grew some fungi, some types with melanin and others without melanin, and zapped them with gamma radiation.
The dark fungi grew better when radiated.
"It raises the possibility that there are pigments out there that allow us to capture a lot of energy," Dr Casadevall said.
Scientists have discovered life in recent years that does not rely on the sun - sulphur-eating bacteria and extremophiles that live deep beneath the sea or under Antarctic ice.
"It shows you how nature is resilient and resourceful. Nature can use an energy source wherever it can find it."
Perhaps radiation-loving fungi could serve as a source of food for astronauts living in space for long periods.
"Fungi do well in dark damp places and you could imagine that space is totally radioactive," Dr Casadevall said. Scientists should be able to adapt such pigments for various uses.
- REUTERS
