Chemical Insights into the Antiviral Mechanisms of Marine Sulfated Polysaccharides: An In-Silico Screening and Molecular Docking Study

In recent years, several viral diseases have emerged suddenly, leading to widespread infection and fatalities. SARS-CoV-2, which appeared in late 2019, mutates frequently, and current vaccines have limited effectiveness in fully preventing SARS-CoV-2 infections. As a result, natural antiviral medicines have gained attention, particularly sulfated polysaccharides from seaweeds, which are promising sources of bioactive compounds for antiviral activity and immune support. This study screened the types of sulfated polysaccharides, such as carrageenan, fucoidan, and ulvan, using computational analysis to evaluate their antiviral potential against SARS-CoV-2. Molecular docking was conducted to examine potential interactions with human ACE2, SARS-CoV-2's RBD, and main protease. The results of molecular docking analysis showed that kappa carrageenan exhibited better docking scores of -9.3 kcal/mol with ACE2 and -8.1 kcal/mol with spike protein-RBD. Meanwhile, carrageenan showed a better docking score of -7.6 kcal/mol with the main protease. The prediction of drug compounds based on RO5 indicates that all bioactive test compounds have the potential to be used as therapeutic agents. It is concluded that the sulfated polysaccharides derived from red seaweed, namely carrageenan and its derivatives, exhibit greater potential in demonstrating antiviral activity against SARS-CoV-2 compared to fucoidan and ulvan.