The world is anxiously awaiting the arrival of a coronavirus vaccine. Until one becomes available, you may want to consider adding more dark chocolate or green tea to your diet—in addition to practicing social distancing and wearing a mask.
De-Yu Xie, a professor of plant and microbial biology, and Yue Zhu, a Ph.D. student in Xie's lab at North Carolina State University, have found that the chemical compounds in certain foods and beverages may prevent certain enzymes in the new coronavirus cells from replicating.
According to their study published in the journal Frontiers, dark chocolate, green tea, and muscadine grapes (a breed that's native to the south) all contain chemical compounds which can bind to and effectively block the function of the protease in SARS-CoV-2, the virus which causes COVID-19. If protease replication is inhibited, the spread of a virus is effectively stopped.
"One of our lab's focuses is to find nutraceuticals in food or medicinal plants that inhibit either how a virus attaches to human cells or the propagation of a virus in human cells," Xie said in a statement. (Related: The One Vitamin Doctors Are Urging Everyone to Take Right Now)
What did the authors look at, exactly?
The researchers observed how the main protease (Mpro) in the SARS-CoV-2 virus reacted once it came into contact with different plant chemical compounds, in particular ones which exhibit both anti-inflammatory and antioxidant properties. They studied the Mpro through both computer simulations and lab studies.
The computer simulations showed that specific chemical compounds from cacao powder, dark chocolate, green tea, and two variety of muscadine grapes were able to bind to different portions of Mpro.
"Mpro has a portion that is like a 'pocket' that was 'filled' by the chemical compounds," Xie said. "When this pocket was filled, the protease lost its important function."
The lab experiments yielded similar results—chemical compounds in green tea and muscadine grapes completely inhibited Mpro's function. The compounds found in dark chocolate and cacao powder, on the other hand, reduced activity by about half.
"Green tea has five tested chemical compounds that bind to different sites in the pocket on Mpro, essentially overwhelming it to inhibit its function," Xie said. "Muscadine grapes contain these inhibitory chemicals in their skins and seeds. Plants use these compounds to protect themselves, so it is not surprising that plant leaves and skins contain these beneficial compounds."
This isn't to say that these foods and beverages will protect you from COVID-19, but these findings may be a catalyst of bigger discoveries to come.