Phytochemical Screening, Antioxidant and Antibacterial Activity of Martynia annua L. Leaf Extracts

Abstract

In the quest for natural antioxidants and antibacterial chemicals to fight oxidative stress and antimicrobial resistance, medicinal plants continue to be an essential source of innovative therapeutic agents. The goal of the current research was to assess the antibacterial potential, antioxidant activity, and phytochemical components of various solvent extracts of Martynia annua L. leaves. Petroleum ether, ethanol, and distilled water were used in cold maceration to create leaf extracts. Alkaloids, flavonoids, phenolics, tannins, glycosides, terpenoids, steroids, saponins, carbohydrates, and proteins were found in preliminary phytochemical screening; the ethanolic extract showed the widest range of secondary metabolites. The ethanol extract had the greatest total phenolic content (112.45 ± 3.28 mg GAE/g) and total flavonoid content (68.74 ± 2.01 mg QE/g), according to quantitative estimate. The DPPH free-radical scavenging test was used to measure antioxidant activity. The ethanolic extract showed a dose-dependent response with the lowest IC•₀ value of 45.23 µg/mL, while the aqueous extract had a value of 74.85 µg/mL. When Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa were screened for antibacterial activity using agar well diffusion and broth microdilution, the ethanol extract demonstrated the strongest activity, with the largest zone of inhibition (18.14 ± 0.68 mm) and the lowest minimum inhibitory concentration (0.625 mg/mL) against B. subtilis. There was very little action in the petroleum ether extract. These findings confirm the traditional therapeutic usage of M. annua and call for further separation and characterisation of its bioactive components. They also show that the ethanolic leaf extract of M. annua is a potential source of antioxidant and antibacterial phytochemicals.