Abstract
Libyan medicinal plants are an important source of therapeutic agents, and Cotula cinerea, a plant collected from the southwestern desert of Libya, is evaluated in this study for its phytochemical composition, antibacterial activity, and antioxidant potential for the first time. Soxhlet extraction using three solvents (n-hexane, chloroform, and methanol) was employed to compare the biological activities of the resulting extracts. The antibacterial activity was assessed using the disc diffusion method against Staphylococcus aureus and Escherichia coli, with ciprofloxacin as the positive control and DMSO as the negative control. Antioxidant activity was evaluated using the DPPH radical-scavenging assay, with ascorbic acid serving as the positive control. The analysis identified tannins, flavonoids, cardiac glycosides, terpenoids, and steroids, while testing negative for coumarins, anthraquinones, alkaloids, and saponins. None of the extracts exhibited antibacterial activity against Escherichia coli. However, the n-hexane extract showed the strongest activity against Staphylococcus aureus (23 mm) inhibition zone, followed by the chloroform extract (16 mm), while the methanolic extract demonstrated the lowest activity (11 mm). Only the chloroform and methanolic extracts demonstrated measurable antioxidant activity compared with the reference standard. This study provides the first phytochemical profiling and biological evaluation of Cotula cinerea growing in Libya. The study concludes that its antibacterial and antioxidant activities are solvent dependent