- Green tea, muscadine grapes and dark chocolates contain chemical enzymes that bind and block the function of main protease enzyme (Mpro) in the coronavirus
- Chemicals present in green tea and muscadine grapes completely inhibit Mpros functions
- Cocoa powder and dark chocolate reduced Mpro activity to half of the original
Green tea, muscadine grapes (grapes native to the United States) and dark chocolates contain chemical enzymes that bind and block the function of specific enzymes or protease (an enzyme required for protein breakdown) in the coronavirus. This study was done at North Carolina State University by plant biologists.
The function of the main protease (Mpro) enzyme in SARS-CoV-2 is blocked. De-Yu Xie, professor of plant and microbial biology at NC State and the corresponding author of the study, commented that proteases are important to the health and viability of the cells and viruses.
"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," said Xie.
"Mpro in SARS-CoV-2 is required for the virus to replicate and assemble itself. If we can inhibit or deactivate this protease, the virus will die." said Xie
Computer simulation studies showed that certain chemical compounds present in green tea, cocoa powder, dark chocolate and two varieties of muscadine grapes interacted and showed binding to two different portions of Mpro.
The invitro lab experiments done by Yue Zhu, an NC State Ph.D. student in Xie's lab, showed similar results. Mpro's function was very successfully inhibited by the chemicals present in green tea and muscadine grapes. Cocoa powder and dark chocolate reduced Mpro activity to half of the original.
Xie said, "Mpro has a portion that is like a 'pocket' that was 'filled' by the chemical compounds. When this pocket was filled, the protease lost its important function."
Xie commented,"Green tea has five tested chemical compounds that bind to different sites in the pocket on Mpro, essentially overwhelming it to inhibit its function. 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."