Chemical compounds in food or beverages such as green tea, grapefruit muscadine and dark chocolate can bind and block the function of a particular enzyme or protease in the SARS-CoV-2 virus, according to a new study by plant biologists from North Carolina State University.
Proteases are important for the health and viability of cells and viruses, says De-Yu Xie, a professor of plant and microbial biology in the state of NC and co-author of the study. If proteases are inhibited, cells cannot perform many important functions – such as replication, for example.
One of the main directions of our laboratory is to find nutrients in food or medicinal plants that prevent the virus from binding to human cells or the spread of the virus in human cells. “
De-Yu Xie, Professor of Plant and Microbial Biology, NC State
In the study, NC researchers conducted computer simulations and laboratory studies showing how the so-called “major protease” (Mpro) in SARS-CoV-2 virus reacted when confronted with a number of different plant chemical compounds already known for their potent anti-inflammatory and antioxidant properties.
“The Mpro in SARS-CoV-2 is needed for the virus to replicate and assemble,” Xie said. “If we manage to inhibit or deactivate this protease, the virus will die.”
Computer simulations showed that the studied chemical compounds from green tea, two varieties of muscadine grapes, cocoa powder and dark chocolate could bind to different parts of Mpro.
“Mpro has a part that’s like‘ pockets ’that are“ filled ”with chemical compounds,” Xie said. “When this pocket filled up, the protease lost its important function.”
In vitro laboratory experiments completed by Yue Zhu, Dr. Sc. An NC student at Xie Lab, he showed similar results. The chemical compounds in green tea and muscadine grapes have been very successful in inhibiting Mpro function; chemical compounds in cocoa powder and dark chocolate reduced Mpro activity by about half.
“Green tea has five tested chemical compounds that bind to different places in the pocket on the Mpro, basically overpowering it to prevent its function,” Xie said. “Muscadine grapes contain these inhibitory chemicals in the skin and seeds. Plants use these compounds to protect themselves, so it’s no surprise that the leaves and bark of the plants contain these beneficial compounds.”
North Carolina State University
Zhu, Y & Xie, DY (2020) Characterization of adhesion and in vitro inhibitory activity of flavan-3-ol and dimeric proanthocyanidins against the major protease activity of SARS-Cov-2. Boundaries in plant science. doi.org/10.3389/fpls.2020.601316.