Screening for phytochemicals

Phytochemicals with antiviral, antimicrobial, and antioxidant properties were screened based on the previous literature and were sorted, filtered based on their geographical origin [31–33]. More than 100 compounds were initially screened. 3D and 2D structures were downloaded from PUBCHEM database [34] and drugbank.ca [35] in both SDF and Simplified Molecular Input Line Entry System (SMILES) format [36] for further screening procedures. In order to select the potential drug-like compounds, several filters were applied on the structures.

Initially, LIPINSKI rule of five (RO5) was applied to screen potential drug-like compounds [37]. Drug-like compounds screened from RO5 was further fed into SWISS-ADME server for screening based on the pharmacokinetics, drug-likeliness, and medicinal chemistry friendliness of small molecules [38]. In addition, the physicochemical properties and the drugability of the selected compounds were also predicted with SWISS-ADME server. Hydroxychloroquinone (HCQ) (PUBCHEM ID: 3652), a well-known retro viral drug was used as a standard throughout the studies [39].