Bananas could help to fight flu and Aids after scientists engineered an anti-viral drug from a substance found in the fruit.
Researchers have known for some time that the fruit carries a virus-busting protein called banana lectin which is so powerful it can even stop HIV getting into cells. But banana lectin - or BanLec - is so potent that it causes a major immune response which causes a dangerous level of inflammation.
Now scientists at the University of Michigan have engineered the protein so that it still stops viruses but without the harmful side effects.
The new form of BanLec has been shown to work against the viruses that cause Aids, hepatitis C and influenza in tests in tissue and blood samples without causing inflammation. It even protected mice from being infected with flu.
If found to work in humans it would be the first broad spectrum anti-viral ever created.
"What we've done is exciting because there is potential for BanLec to develop into a broad spectrum antiviral agent, something that is not clinically available to physicians and patients right now," said Dr David Markovitz, co-senior author of the paper, which was published in the journal Cell.
"But it's also exciting to have created it by engineering a lectin molecule for the first time, by understanding and then targeting the structure."
Banana lectin works by sticking to chains of sugar molecules. Most of the world's deadliest viruses, including Mers, flu, Ebola and HIV are covered in the type of sugar molecules banana lectin adheres to.
Prof Wendy Barclay, a virologist from Imperial College London, said: "This piece of research not only takes forward a new strategy for combating a wide range of viruses but elegantly shows why it works.
"It is beautiful science with a truly translational impact. Let's hope it can go further than just testing in mice."
Prof Ron Eccles, director of the common cold centre at Cardiff University, said: "We really need new antivirals to fight diseases like common cold and flu and the research published on a new antiviral engineered from a substance in bananas could give hope for new antiviral drugs."
