Exploring Antibacterial, Antioxidant, Cytotoxic Potential of Oscillatoria sp.-Derived Metabolites and Their Molecular Docking with Estrogen Receptor-α.

Anthropogenic activities have led to the accumulation of carcinogenic toxicants in the food chain, posing severe risks to both human and animal health. Bioactive molecules derived from terrestrial and aquatic systems offer promising solutions to various health challenges. Presently, the cyanobacterial metabolites from ethyl acetate extract of Oscillatoria sp. (EAEOs) were evaluated for its antiproliferative, antioxidant, and antimicrobial effects. The EAEOs resulted significant antibacterial zones (12 ± 2.5, 17 ± 1.7, 14 ± 0.3, and 14 ± 2.6 mm) on Staphylococcus aureus, Escherichia coli, Bacillus subtilis, and Bacillus cereus, respectively. EAEOs also exhibited free radical scavenging activity with IC₅₀ values of 69.68 µg/mL (DPPH) and 144.4 µg/mL (hydroxyl radicals). Followed by, the EAEOs also exhibited significant inhibition of MCF-7 breast cancer cells (IC50: 54.25 µg/mL) compared to HepG2 and A549 cells (72.6 and 85.6 µg/mL), respectively The EAEOs induced apoptosis and chromosomal damage on targeted cancer cells, and their DNA fragmentation were evidenced. Totally, 17 compounds from EAEOs were identified from GC-MS, in which 2-cyclopenten-1-one, 2-hydroxy-3-methyl (23); piperidine, 1, 4-dimethyl (13); 17-pentatriacontene (7.88); and 3-octadecene (7.09%) are major ones. Molecular docking confirmed that acetamide, n-(2-benzoyl-4chlorophenyl)-2-(2-methylpiperidin-1-yl)- (compound-3) showed strong binding affinity (10.13 kcal/mol) with ERα. Overall, the biological potential of Oscillatoria metabolites were found to be significant. Hence, further screening of preponderant compounds and studying the mechanism are warranted to fulfill their applications in food, pharmaceuticals, and other industries.