Battle Against Coronavirus: Repurposing Old Friends (Food Borne Polyphenols) for New Enemy (COVID-19)

In the era of extreme scientific development where the scientific community have reached beyond moon, the entire world today is facing an immense problem due to deadly effect of COVID-19 (coronavirus disease), originated in Wuhan. Coronavirus is having dexterity to target immune compromised people very easily and swiftly get transmitted to healthy individuals from infected ones. Coronavirus infections are spreading very rapidly, and almost all the countries around the world are having corona positive people and asymptomatic carriers. This pandemic has created havoc both to human health and economy in lack of an effective treatment against this disease. Due to time limitations and urgency to find cure for COVID 19 we have undertaken the help of structure assisted drug design approach which mainly involves virtual screening program which identifies the structural leads which can target COVID-19 main protease (M^pro). This protease is the key enzyme of coronavirus which plays crucial role in virus replication and transcription, which can be targeted to retard the growth of virus inside the host. In the present work, the Phenol explorer database (version 3.6) containing 751 different food borne polyphenols were screened against the (M^pro) to identify suitable structural leads with potential to inhibit this protease though High throughput modelling and molecular docking approach. We identified six potential polyphenols belonging to Sanguiin, Theaflavin gallate, Theaflavin digallate, Kaempferol, Punicalagin and Protocatechuic acid chemical classes. All the six polyphenols have much higher docking scores ≥ -9.8 kcal/mol as compared to peptidomimetic inhibitor (N3) of COVID 19 virus M^pro. Pharmacokinetic and Drug likeness predictions of these polyphenols were done using SwissADME web tool where Protocatechuic acid shown fairly good results (1 Lipinski violation). The studies suggest the dietary intake of “black tea” can improve the resistance to fight against COVID 19 virus in early stages of human infection. Importantly though, the enriched subset of six compounds identified from the larger library has to be validated experimentally.