Sargassum wightii Greville ex J.Agardh Grevilli Extract with Macromolecular Protection Activity In Vitro: Prospecting for Novel Drug Leads Using GC-MS Based Metabolic Profiling

Marine macro alga are known to produce a plethora of bioactive metabolites with potential application in pharmaceutical and nutritional product development. In this study, the brown algae Sargassum wightii was collected along the coast of Kovalam, Thiruvananthapuram and subjected to in vitro analysis to determine their bioactive properties. The chloroform-methanol extract of S. wightii was utilized to screen and quantify phytochemical components. Further, the study examined the antioxidant potentials by lipid peroxidation inhibition, DPPH, and ABTS radical scavenging assays followed by an antibacterial activity. The capability of the extract to inhibit DNA damage and protein oxidation was also evaluated in vitro. Finally, the chemical characterization was attained using UV-Visible, FTIR, and GC-MS spectral data. Alkaloids, coumarins, flavonoids, phenols, and tannins, were detected in preliminary qualitative phytochemical analysis and their quantitative estimation revealed a significant concentration of these phytocomponents. The extract showed an IC50 value of 310.53 ± 0.35 µg/mL and 242.85 ± 0.377 µg/mL for DPPH and ABTS free radicals respectively. Whereas an IC50 of 205.42 ± 0.20 µg/mL was estimated for lipid peroxidation inhibition assay. A significant antimicrobial activity against four bacterial pathogens with a maximum zone of inhibition of > 40 mm was also observed against Staphylococcus aureus 1.5 µg/mL). The extract also demonstrated a high capability for concentration-dependent prevention of DNA damage and protein oxidation. The GC-MS spectral peaks confirmed the occurence of 17 active components with reported biological activities. These findings suggest that the extract of S. wightii, can be a lead compound for the development of a promising pharmaceutical product.