Antibacterial potential of selected medicinal plant leaf extracts against some pathogens

Abstract

This study investigates the antimicrobial activity of leaf extracts from selected medicinal plants, Cinnamomum tamala (bay leaf), Polyalthia longifolia (Ashoka), Cymbopogon citratus (lemongrass), Amomum subulatum (black cardamom), and Andrographis paniculata (bhui neem) against pathogenic bacterial strains: Proteus mirabilis, Staphylococcus aureus, Pseudomonas aeruginosa, Enterococcus faecalis, and Escherichia coli. Using the agar well diffusion assay, different extract concentrations (100–250 µL) were tested for antimicrobial efficacy. Results revealed that A. subulatum exhibited the strongest activity against P. mirabilis (Zone of inhibition: 20 mm at 150 µL), while C. citratus demonstrated remarkable inhibition against E. coli (39 mm at 250 µL) and E. faecalis (25 mm). A. paniculata showed potent activity against P. aeruginosa (26 mm at 250 µL), and P. longifolia was highly effective against S. aureus (30 mm). These findings suggest the potential of these plant extracts as promising natural antimicrobials and support further pharmacological investigations for clinical application in managing bacterial infections.