Extracts from two wild plants inhibit COVID-19 virus, study finds
Two common wild plants contain extracts that inhibit the ability of the virus that causes COVID-19 to infect living cells, an Emory University study finds. Scientific Reports published the results — the first major screening of botanical extracts to search for potency against the SARS-CoV-2 virus.
In laboratory dish tests, extracts from the flowers of tall goldenrod (Solidago altissima) and the rhizomes of the eagle fern (Pteridium aquilinum) each blocked SARS-CoV-2 from entering human cells.
The active compounds are only present in miniscule quantities in the plants. It would be ineffective, and potentially dangerous, for people to attempt to treat themselves with them, the researchers stress. In fact, the eagle fern is known to be toxic, they warn.
The researchers devised experiments with virus-like particles, or VLPs, of SARS-CoV-2, and cells programmed to overexpress ACE2 on their surface. The VLPs were stripped of the genetic information needed to cause a COVID-19 infection. Instead, if a VLP managed to bind to an ACE2 protein and enter a cell, it was programmed to hijack the cell’s machinery to activate a fluorescent green protein.
A plant extract was added to the cells in a petri dish before introducing the viral particles. By shining a fluorescent light on the dish, they could quickly determine whether the viral particles had managed to enter the cells and activate the green protein.
The researchers identified a handful of hits for extracts that protected against viral entry and then homed in on the ones showing the strongest activity: tall goldenrod and eagle fern. Both plant species are native to North America and are known for traditional medicinal uses by Native Americans.
