Keywords
Fresh ginger
Gram Negative Bacteria
Abstract
The global rise of antimicrobial resistance (AMR) in Gram-negative pathogens necessitates the exploration of efficacious, plant-derived therapeutic alternatives. This study provides a comparative analysis of the bactericidal efficacy of aqueous and ethanol extracts of Syzygium aromaticum (clove) and Zingiber officinale (ginger) against clinical isolates of Escherichia coli, Klebsiella spp., and Salmonella spp. Agar well diffusion, broth dilution (MIC), and sub-culturing (MBC) methods, were used to evaluate the concentration-dependent responses of the isolates. The results indicate that ethanol-extracted clove possesses superior antimicrobial potency, producing mean inhibition zones of 26.00 ± 1.00 mm against E. coli, which rivaled the positive control, gentamicin. Quantitative analysis revealed that ethanol clove extract acts as a definitive bactericidal agent, with MBC/MIC ratios ranging from 0.5 to 4.0. In contrast, ginger extracts exhibited primarily bacteriostatic activity, with MBC values exceeding 400 mg/ml for all isolates. Multi-factor ANOVA confirmed that extract type (F = 380.37, p < 0.0001) and solvent polarity were primary determinants of efficacy. The discussion highlights that while ginger's antimicrobial role is limited, the bactericidal capacity of ethanol-extracted clove was statistically significant. By differentiating between mere bacteriostatic and bactericidal effects, this study identifies clove as a potent alternative for future standardized phytotherapeutic formulations. These results underscore the potential for incorporating clove-derived bioactive compounds into antimicrobial stewardship programs, particularly in resource-limited settings where accessible and effective alternatives to synthetic antibiotics are urgently required to combat MDR-related infections.References
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