Exploring the Bioactivity of Plectranthus species: A Sustainable Solution to Antimicrobial Resistance

The escalating antimicrobial resistance (AMR) crisis necessitates innovative and sustainable solutions to address resistant pathogens. This study investigates the antimicrobial potential of five Plectranthus species: Plectranthus prostratus, Plectranthus scutellarioides, Plectranthus barbatus, Plectranthus amboinicus, and Plectranthus caninus. Methanolic extracts of these species were assessed for antibacterial activity against Escherichia coli, Bacillus subtilis, and Salmonella Typhi using the agar well diffusion method. The results demonstrated significant dose-dependent inhibition, with P. amboinicus and P. barbatus showing the most potent activity across all tested strains, achieving maximum zones of inhibition (ZOI) of 19 ± 0.5 mm and 20 ± 0.4 mm, respectively. Bacillus subtilis was the most susceptible strain, while Salmonella Typhi displayed the least sensitivity. These findings highlight the potential of Plectranthus species as eco-friendly alternatives to synthetic antimicrobials. Future research aimed at isolating and characterizing the bioactive compounds from these plants could enhance their therapeutic applications and contribute to developing sustainable strategies to combat AMR.