Relationship between polyphenol content and anti‐influenza viral effects of berries

Abstract

Antiviral effects were found to differ markedly between berry species. Rabbiteye varieties tended to have higher antiviral effects than Northern, Southern and Half Highbush blueberry varieties. We also found that Natsuhaze, which has recently been harvested in Japan as a potential functional food, had an antiviral effect comparable to that of bilberry, cranberry and blackcurrant. There was a positive relationship between antiviral activity and polyphenol content, indicating the possibility that polyphenol is one of the key factors in the antiviral effects of berries.