Occurrence of a highly antiviral agent in plants treated with Boerhaavia diffusa inhibitor
A naturally occurring glycoprotein present in Boerhaavia diffusa root extract (BD inhibitor), causes plant cells to produce a highly active antiviral agent (AVA) that defends cells against infection by viruses. AVA was present in inhibitor-treated plants only, but not in nontreated plants, and was produced 2–48 h after treatment with BD inhibitor. AVA was effective not only in plant species in which it was produced but in other plant species as well. Crude AVA was active both in vitro and in vivo. In vitro, it markedly reduced the infectivity of viruses, and in vivo, the virus content in AVA-treated leaves and leaf discs was considerably suppressed. The AVA showed the characteristics of protein.