Phytochemical Profiling and Bioactivity of Dodonaea viscosa L. Leaf Extract

Abstract

The increasing prevalence of drug-resistant pathogens necessitates the exploration of alternative therapeutic agents derived from natural sources. This study investigated the phytochemical composition, functional groups, antioxidant capacity, and antimicrobial potential of the ethanolic leaf extract of Dodonaea viscosa L. Qualitative phytochemical screening revealed the presence of alkaloids, phenols, flavonoids, tannins, resins, and saponins in the extract. Fourier Transform Infrared (FT-IR) spectroscopy confirmed the presence of key functional groups, including phenolic hydroxyl (O-H), aliphatic C-H, aromatic C=C, and aliphatic C-O, which are characteristic of bioactive compounds. The extract demonstrated significant antioxidant activity in the DPPH free radical scavenging assay, achieving a maximum scavenging percentage of 93% at 20 ?g/mL, which was comparable to that of the ascorbic acid control (95%). Antimicrobial assays showed notable dose-dependent antibacterial activity against Staphylococcus aureus and Escherichia coli, with Minimum Inhibitory Concentrations (MICs) of 6.25 mg/mL and 12.5 mg/mL, respectively. However, the extract was ineffective against Pseudomonas aeruginosa and Candida albicans. These findings suggest that the leaf extract of D. viscosa is a rich source of phenolic and flavonoid compounds with strong antioxidant and selective antibacterial properties, supporting its traditional medicinal use.