Broad-Spectrum Antibacterial Efficacy of Novel Plant Extract Combinations Assessed Through Well Diffusion Analysis

The rise of multidrug-resistant (MDR) pathogens has intensified the need for novel and effective antimicrobial alternatives. This study evaluated the antibacterial activity of Cinnamon (CI) extract—alone and in combination with Ajwain (AJ), Nigella seeds (NS), and Mulethi (ML)—using the well diffusion method against Klebsiella pneumoniae, Salmonella typhi, Bacillus subtilis, and Listeria monocytogenes. Extracts were tested at 100, 50, and 25 mg/mL, with ciprofloxacin as the positive control. CI demonstrated measurable, concentration-dependent inhibition across all bacterial strains, with the highest activity observed against S. typhi. Although the standard antibiotic exhibited superior potency, the plant extracts produced consistent inhibitory effects, indicating meaningful antibacterial potential. The results suggest that CI and its multi-extract formulations may serve as promising natural antimicrobial agents. Further studies on phytochemical profiling, synergistic interactions, and MIC determination are recommended to support their use against drug-resistant pathogens.