ANTIMICROBIAL ACTIVITY OF EGYPTIAN MIMOSA SEED EXTRACT AGAINST PSEUDOMONAS AERUGINOSA

ABSTRACT Pseudomonas aeruginosa is a clinically significant Gram-negative pathogen associated with severe wound, urinary, and respiratory infections, and is increasingly difficult to treat due to rising multidrug resistance, particularly in resource-limited settings such as Borno State, Nigeria. This study investigated the antimicrobial activity of Mimosa pudica (Egyptian mimosa) seed extract as a potential alternative therapeutic agent against multidrug-resistant (MDR) P. aeruginosa. Seeds were collected, authenticated, dried, pulverized, and extracted using ethanol and methanol. Phytochemical screening of the crude extract revealed the presence of flavonoids, phenolic compounds, saponins, alkaloids, steroids, and proteins, while quinones and glycosides were absent, indicating a rich profile of bioactive metabolites with known antimicrobial potential. The test organism, identified through morphological and biochemical characteristics, exhibited complete resistance (0 mm zone of inhibition) to all standard antibiotics tested, including ciprofloxacin, gentamicin, streptomycin, Augmentin, and others. Antibacterial activity of the extract was assessed using the agar well diffusion method at concentrations of 100–400 mg/mL. The extract demonstrated clear, dose-dependent inhibition of P. aeruginosa, with zones of inhibition ranging from 14 mm at 100 mg/mL to 22 mm at 400 mg/mL. The highest concentration produced markedly superior activity compared to all conventional antibiotics tested. These findings indicate that Mimosa pudica seed extract contains potent bioactive compounds capable of suppressing MDR P. aeruginosa, supporting its traditional medicinal use and highlighting its potential as a basis for developing novel plant-based antimicrobial agents. The study concludes that Mimosa pudica seeds represent a promising source of natural antibacterial compounds and recommends further work on compound isolation, toxicity assessment, formulation development, and testing against broader panels of clinical isolates.