Phytochemical Analysis, Antimicrobial, Antioxidant, Anti-Inflammatory, and Cytotoxic Properties of Acacia nilotica Leaf Extract

Abstract

Acacia nilotica is a medicinal plant widely used in traditional medicine. This study evaluated the phytochemical composition and antimicrobial, antioxidant, anti-inflammatory, and cytotoxic activities of the ethanolic leaf extract. Leaves were collected from Khartoum, Sudan, authenticated, dried, and extracted with 75% ethanol using maceration. Phytochemical screening was performed using standard test methods. The total phenolic content (TPC) and total tannin content (TTC) were determined spectrophotometrically. Antibacterial activity was tested against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa using the agar well diffusion method. Antioxidant activity was assessed via DPPH radical scavenging, anti-inflammatory activity via egg albumin denaturation inhibition, and cytotoxicity via the brine shrimp lethality assay. The extract contained alkaloids, flavonoids, tannins, terpenoids, coumarins, and sterols. TPC was 169.62 ± 0.06 mg GAE/g, and TTC was 63.85 ± 0.05 mg TAE/100 g. The extract exhibited moderate antibacterial activity, with inhibition zones ranging from 13.0 to 17.0 mm. Antioxidant IC₅₀ was 13.7 µg/mL, and anti-inflammatory IC₅₀ was 280.7 µg/mL. The cytotoxicity against Artemia salina showed an LD₅₀ of 183.3 µg/mL, indicating high toxicity. These findings suggest that A. nilotica leaf extract possesses promising bioactive properties, supporting its traditional medicinal use.