Mimosa pudica

Medicinal plants have long served as a vital source of bioactive compounds with therapeutic potential against a wide range of microbial pathogens. The increasing incidence of antibiotic resistance among pathogenic bacteria has renewed scientific interest in exploring plant-derived compounds as alternative antimicrobial agents. Mimosa pudica (commonly known as the “Sensitive Plant” or “Touch-Me-Not”) is a medicinal herb traditionally used in folk medicine for its reported antimicrobial, anti-inflammatory, and wound-healing properties. This study evaluated the phytochemical constituents and antibacterial activity of hot and cold water extracts of Mimosa pudica against three clinically significant bacterial isolates: Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. Qualitative phytochemical screening revealed the presence of saponins, flavonoids, and tannins, while terpenoids and glycosides were absent. Tannins were moderately present (++) in both extracts, suggesting their possible contribution to the plant’s antimicrobial potential. The antibacterial assay demonstrated concentration-dependent inhibitory effects against all test organisms. The cold extract exhibited higher antibacterial activity than the hot extract, with Staphylococcus aureus showing a maximum zone of inhibition of 26.00 ± 5.29 mm at 2000 mg/ml, compared to 8.00 ± 5.29 mm for the hot extract. Similarly, the cold extract showed superior inhibition against Escherichia coli (27.33 ± 6.11 mm) and Pseudomonas aeruginosa (18.67 ± 7.57 mm) at the highest concentration. The Minimum Inhibitory Concentration (MIC) values revealed that Staphylococcus aureus was most susceptible to the cold extract (80 mg/ml), whereas Pseudomonas aeruginosa exhibited the least susceptibility (175 mg/ml for both extracts). The Minimum Bactericidal Concentration (MBC) results indicated that both extracts were bacteriostatic rather than bactericidal at the tested concentrations (2000 mg/ml). Comparative antibiotic sensitivity tests showed that the bacterial isolates displayed varying degrees of resistance and susceptibility to standard antibiotics, underscoring the need for effective plant-based alternatives. Overall, the findings demonstrate that Mimosa pudica possesses promising antibacterial activity, particularly in its cold water extract, likely due to the presence of tannins, saponins, and flavonoids. These results support the traditional use of Mimosa pudica in herbal medicine and suggest its potential as a natural source of antimicrobial compounds for combating bacterial infections, especially those caused by antibiotic-resistant pathogens. x