Bacteria found in a traditional Japanese pickle could prevent flu, a study suggests.
Scientists investigated the immune-boosting powers of Lactobacillus bugs in Suguki, a pickled turnip popular in Japan.
"Our results show that when a particular strain of Lactobacillus brevis is eaten by mice, it has protective effects against influenza virus infection," said lead researcher Naoko Waki, from the Japanese food company Kagome.
The findings are published in the journal Letters in Applied Microbiology. Human trials using a probiotic drink containing the same KB290 strain of the bug are under way.
A protective layer of sugars called exopolysaccharides that protects the bacteria against acid stomach juices could lie behind its powers, the Japanese researchers believe.
"We know that exopolysaccharides have immune boosting effects in other similar bacteria, so we wonder if the exopolysaccharides of KB290 are responsible for the effects we see," said Ms Waki.
In the mouse study, the bacteria increased the production of immune system molecules including flu-specific antibodies. The effect was strong enough to prevent infection by the H1N1 strain of flu.