A ground breaking collaborative study by researchers from Hyderabad-based Centre for Cellular and Molecular Biology (CCMB) and Institute of Himalayan Bioresource Technology (IHBT), Himachal Pradesh, has shown that Theaflavin 3-gallate, a naturally occurring bioactive molecule derived from Theaflavin, found in abundance in black tea, has the ability to limit replication of SARS-CoV-2 coronavirus.
The CCMB-IHBT collaborative study ‘Theaflavin 3-gallate inhibits the main protease (Mpro) of SARS-CoV-2 and reduces its count in vitro’ was published in the prestigious Nature journal on July 30.
Theaflavin is a chemical in black tea that is formed from fermentation of green tea and is commonly used as a medicine for various medical conditions. Despite lack of hard scientific data, people tend to consume the naturally occurring Theaflavin through black tea to control cholesterol, hypertension, heart disease, obesity, diabetes and even for cancer.
In the study, the CCMB-IHBT researchers explored the possibility of the application of Theaflavin 3-gallate in preventing the ability of SARS-CoV-2 to quickly multiply.
Headed by the CCMB research lab of senior scientist, B Kiran Kumar, the study noted, “the main protease
(Mpro) of SARS-CoV-2 has been recognized as an attractive drug target because of its central role in viral replication. Overall, our findings suggest that Theaflavin 3-gallate effectively targets the Mpro thus limiting the replication of the SARS-CoV-2 virus in vitro”.
The research group said, “our previous preliminary molecular docking studies showed that Theaflavin 3-gallate exhibited better docking scores than repurposed drugs like Atazanavir, Darunavir and Lopinavir. In this study, conventional and steered MD-simulations analysis revealed stronger interactions of theaflavin 3-gallate with the active site residues of Mpro than Theaflavin and a standard molecule GC373, which is a known inhibitor of Mpro and novel broad-spectrum anti-viral agent”.
The researchers in their in-vitro (laboratory) study demonstrated that treatment of SARS-CoV-2 with 200 μM (micrometre) of theaflavin 3-gallate in-vitro using Vero cells and quantifying viral transcripts leads to reduction of viral count by 75 per cent.
“Overall, our findings suggest that theaflavin 3-gallate effectively targets the Mpro thus limiting the replication of the SARS-CoV-2 virus in vitro,” the researchers added.