Flavanols, proanthocyanidins found in dark chocolate, grapes, green tea may block SARS-CoV-2 proteins

While the search for drugs and vaccines that are effective against the SARS-CoV-2 virus is intensifying in an effort to control the COVID-19 pandemic, a similar quest is being undertaken by researchers to explore natural and plant-based treatments. Recent studies not only show that immunonutrition can play a huge role in the prevention of and recovery from COVID-19 infection but also suggest that cannabis extracts have the potential of blocking the SARS-CoV-2 virus. A new study published in the journal Frontiers in Plant Science suggests that certain nutraceutical compounds like flavanols and proanthocyanidins (PAs) found in some plant-based sources can inhibit SARS-CoV-2 proteins or proteases. The study, conducted by plant biologists based at the North Carolina State University, suggests that many subtypes of these phytonutrients were able to successfully block the activity of the main protease (MPro) of SARS-CoV-2. Flavanols, proanthocyanidins and virus inhibition It must be noted that recent studies into the anti-inflammatory, antiviral and antibacterial properties of these phytonutrients have also shown promising results. Flavanols, in particular, have already been shown through research to be effective in lowering blood pressure levels and promoting cerebrovascular and cognitive functions . The researchers behind the new study used dynamic docking simulations (the method of simulating molecular recognition and binding used by drug design groups and pharmaceuticals) to introduce various subtypes of flavanols and proanthocyanidins to MPro on a computer. The phytonutrients were extracted from five plant sources: green tea, cacao seed powder, dark chocolate (from Ecuador) and two types of muscadine grapes. The 10 flavanol subtypes examined included catechin, afzelechin, gallocatechin and epigallocatechin. The two PAs included procyanidin A2 and B2. A total of 12 nutraceutical compounds were thus tested during this study. Phytonutrient activity against SARS-CoV-2 The researchers conducted various levels of tests to finally reach the conclusion that all 12 of these compounds were able to bind to MPro, with procyanidin A2 and B2 having the highest docking affinity scores followed by epicatechin-3-O-gallate (ECG), gallocatechin-3-O-gallate (GCG), epigallocatechin-3-O-gallate (ECGC), catechin-3-O-gallate (CAG) and other flavan-3-ol aglycones. Further in vitro analyses showed that 10 out of these 12 compounds were also able to block MPro activity and replication. Rich extracts from the five food sources were also used to create an inhibitory assay which confirmed the fact that these compounds can effectively inhibit SARS-CoV-2 MPro activity. Given their findings, the researchers concluded that these nutraceutical compounds and rich extracts of green tea, muscadine grapes, cacao powder and dark chocolate can be used widely to effectively stop the devastation caused by the SARS-CoV-2 virus. The need to immediately exploit the now-proved benefits of these plant-based food sources is especially important, the researchers say, as effective medicines for the treatment of COVID-19 are still lacking and no vaccine has been successfully introduced yet. For more information, read our article on Chocolate. Health articles in Firstpost are written by myUpchar.com, India’s first and biggest resource for verified medical information. At myUpchar, researchers and journalists work with doctors to bring you information on all things health.