Researchers at North Carolina State University have discovered compounds in green tea, muscadine grapes and dark chocolate can inhibit a SARS-CoV-2 protease. By inhibiting proteases viruses cannot perform important functions, such as replication.
"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," according to De-Yu Xie, professor of plant and microbial biology at NC State and the corresponding author of the study.
The researchers performed computer simulations and lab studies demonstrating how the main protease or Mpro in the 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.
"Mpro in SARS-CoV-2 is required for the virus to replicate and assemble itself," Xie said. "If we can inhibit or deactivate this protease, the virus will die."
Computer simulations revealed the chemical compounds from green tea, two varieties of muscadine grapes, cacao powder and dark chocolate were capable of binding to different portions of Mpro.
"Green tea has five tested chemical compounds that bind to different sites in the pocket on Mpro, essentially overwhelming it to inhibit its function," stated Xie. "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."