Italian scientists have made "very good" sourdough from yeast found inside a famous corpse.
Otzi the Iceman, a more than-5,000-year-old dead body, has been the centre of various studies after he was discovered by German hikers in September 1991 in the Otztal Alps.
Now, researchers have found his preserved corpse still contains yeasts which infiltrated his remains shortly after he died.
The specific strains of yeast have adapted to cold environments and continued to colonise his mummified remains, despite his body being stored on an Alpine peak - then in a refrigeration chamber at -6C.
Scientists in Italy have made dough from the remaining yeast and published their findings in the journal Microbiome.
Mohamed Sarhan, a microbiologist at the Eurac Research Institute for Mummy Studies in Italy, said: "It worked. As a dough, it was very very good."
The yeasts could be used by fermentation industries in the future to make more bread or beer, he added.
But Otzi, who was likely murdered by an arrow some 5,300 years ago, has also been inadvertently exposed to modern microbes, and it remains unclear if these, in combination with the ancient yeasts, are hurting or helping preservation efforts.
A sculpture of Otzi, who has had his microbiome turned into sourdough
|GETTY
An inspection of his body revealed he was in his 40s when he died, stood at five feet, three inches tall, and ate ibex, red deer and wheat just before his death.
He contained gut microbes which are most commonly found in today's non-Westernised communities, such as the Hadza hunter-gatherers in Tanzania and people living in rainforests in north eastern Madagascar.
"We have two or three species that were never reported before in [Otzi’s] case that we know already are very rarely found in modern humans," Dr Sarhan said.
Scientists have previously identified some aspects of his microbiome, but Dr Sarhan and his colleauge's research is the first to investigate if microbes were capable of growing under current storage conditions.
LATEST SCIENCE HEADLINES:
Otzi the Iceman was likely murdered in the Italian Alps, allowing him to be preserved
|GETTY
Otzi's internal and external microbiomes has water samples taken and were swabbed.
Samples were also taken from the soil where his body was found as well as his storage environment.
From there, Otzi's genetic material was pieced together and his gut microbiome was determined to be very different from that of his skin.
The team was able to cultivate four cold-adapted yeasts in sample taken from Otzi's skin and thawed water from his insides.
The yeast cells cultivated from the gut of Otzi the Iceman.
|EURAC RESEARCH/ANDREA DI GIOVANNI
Evidence of ancient DNA damage in these yeasts strongly suggested they either laid dormant for 5,300 years or had descended directly from original yeast colonisers, the authors said in the study.
Samples taken from 2019 also determined that one yeast strain, the cold-loving Glaciozyma, had become the dominant strain on Otzi's body since samples were last taken in 2010.
Study co-author Frank Maixner, director of the Eurac Research Institute for Mummy Studies, said: "These yeasts have accompanied Otzi on his long journey through the millennia."
The research demonstrates Otzi is not just a "static relic" but a "dynamic biological system", he added.