Antimicrobial Activity of Garlic Derivatives on Common Causative Microorganisms of the External Ear Canal and Chronic Middle Ear Infections

Özet

Objective: Today, antibiotic resistance is increasing and evolving into an important health problem.Therefore, it is important to research on alternativetherapies to antibiotics. This study aimed to investigate the inhibitory effect of four garlic derivatives onmicroorganisms commonly isolated in ear infections.Methods: The antimicrobial activities of allicin, s-allylcysteine (SAC), diallyl disulfide (DADS), and s-allylmercaptocysteine (SAMC) were investigated on standard strains of commonly isolated microorganismsusing the broth microdilution method. The test strainswere selected among the microorganisms responsiblefor chronic suppurative otitis media and otitis externa.These microorganisms were Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacterbaumannii, Staphylococcus aureus, Enterococcus faecium,Candida albicans, and Candida tropicalis.Results: Minimum inhibitory concentration (MIC)values of allicin and SAC ranged from 0.125 to 20 μg/mL for fermentative bacteria (E. coli and K. pneumoniae), 20 to 80 μg/mL for non-fermentative bacteria(P. aeruginosa and A. baumannii), 5 to 10 μg/mL forgram-positive cocci (S. aureus and E. faecium), and40 to 80 μg/mL for yeasts (C. albicans and C. tropicalis). MIC values of DADS ranged from 40 to 80μg/mL for fermentative bacteria, 40 to 160 μg/mLfor non-fermentative bacteria, 40 to 80 μg/mL forgram-positive cocci, and 20 to 40 μg/mL for yeasts.The MICs of SAMC were >640 μg/mL for the testedbacteria and yeasts.Conclusion: Both allicin and SAC showed antimicrobial activity against the tested microorganisms,even at low concentrations. These two derivatives maybe used to treat infections in the future.