A new finding shows that a chemical found in the bark of the magnolia tree suppresses replication of the SARS-CoV-2 virus, which causes COVID-19, in different types of cells, and may be effective against future coronaviruses.
The researchers discovered that the chemical honokiol reduced the production of infectious SARS-CoV-2 virus particles in treated cells to roughly 1,000th of the prior level.
The study, which was published in the journal Microbiology Spectrum, also found that the compound reduced the replication of other extremely dangerous human coronaviruses, such as Middle East respiratory syndrome (MERS) and Severe acute respiratory syndrome (SARS).
Associate Professor at Leiden University, Netherlands, Martijn J. van Hemert said, “This suggests that it has a broad spectrum of activity and would likely also inhibit novel coronaviruses that might emerge in the future”.
He further said, “If honokiol can be developed into a drug, possibly in combination with other compounds, stockpiling it would help us to increase our preparedness for the emergence of the next coronavirus”.
J. van Hemert stated, “Broad-spectrum medications might then be used to treat early patients and prevent spread, or they could be used prophylactically among healthcare personnel, and in high-risk groups, such as among nursing home residents”.
“Honokiol also possesses anti-inflammatory properties which could be beneficial in cases where patients seek medical therapy at a somewhat late stage of the disease, by which time the body’s own inflammatory responses to the infection are causing symptoms”, J. van Hemert continued.
“At that point, inhibiting of virus replication may no longer be useful”, he explained, “but honokiol’s anti-inflammatory response may mitigate the illness”.
Honokiol blocks a later stage viral replication cycle, once that takes place after the virus has entered the cell.
The researchers believe that honokiol works by activating systems in the host cell that prevent viral multiplication. It did so with the initial SARS-CoV-2 variants, as well as the more recent Omicron variants.
J. van Hemert went on to say, “Our study merely provides the basis for further research into potential therapeutic applications”.
“It is vital to note that it is too early to speculate on the usage of honokiol in SARS-CoV-2 patients. This requires much more research and, if successful, properly conducted clinical trials are required”, the researcher concluded.