Harnessing aquatic weeds for SARS-CoV-2 antiviral activity: A combined molecular docking and vero cell line study

COVID-19, caused by the SARS-CoV-2 virus, has been one of the most widespread diseases in recent times, leading to a significant increase in mortality rates. SARS-CoV-2 belongs to the Coronaviridae family and has mutated into several variants, increasing disease severity and reducing immunity among populations. Although extensive research is ongoing, no definitive treatment for COVID-19 currently exists. Seaweeds are a major source of food, medicine, and fertilizer worldwide. This study aims to determine whether the chemical constituents of seaweeds possess antiviral activity against SARS-CoV-2 infection in humans. Chemical compounds from five seaweed species (Fucus spiralis, Salicornia virginica, Sarcodiotheca gaudichaudii, Sargassum muticum, and Chondrus crispus) were selected for analysis. Molecular docking was performed between SARS-CoV-2 proteins and the chemical constituents of these seaweeds. The results were compared with Remdesivir. Among all the compounds tested, Phlorotannin A and Atropine demonstrated better binding affinity and interaction than Remdesivir, with binding energies of -6.42 kcal/mol and -7.32 kcal/mol against protein 7BZ5, and -6.27 kcal/mol and -6.35 kcal/mol against protein 6LZG, respectively. Drug-likeness screening was conducted to exclude ligands with large molecular weights, and ADMET studies indicated better absorption and lower toxicity for the selected compounds. Furthermore, cytotoxicity and antiviral activity assays showed dose-dependent effects attributable to the bioactive compounds present in the seaweeds, suggesting their potential for developing COVID-19 therapeutics.