Abstract

The escalating threat of antimicrobial resistance (AMR) underscores the urgent need for alternative therapeutic agents, particularly from natural sources. Nigella sativa (black seed) and Cinnamomum zeylanicum (Ceylon cinnamon) are two botanicals widely recognized in traditional medicine for their broad-spectrum antimicrobial properties. This study evaluated the antibacterial activity of extracts from these plants, prepared via maceration, against clinical isolates of both Gram-positive (Staphylococcus aureus and Streptococcus pyogenes) and Gram-negative (Pseudomonas aeruginosa and Escherichia coli) bacteria. Extracts demonstrated inhibitory effects across tested pathogens, with notable activity observed in C. zeylanicum extract at 1 g/mL, which produced zones of inhibition of 28 ± 1 mm against S. aureus, 15 ± 1 mm against E. coli, and 7 ± 1 mm against P. aeruginosa. The combined extract displayed enhanced inhibitory effects compared to individual extracts, suggesting possible synergistic interactions. These findings support continued investigation of N. sativa and C. zeylanicum as potential sources of antimicrobial agents for addressing resistant bacterial infections.^1,2

Keywords

phytochemicals, antimicrobial resistance, Nigella sativa, Cinnamomum zeylanicum, clinical isolates, antibacterial activity