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

OBJECTIVE

Today, antibiotic resistance is increasing and evolving into an important health problem. Therefore, it is important to research on alternative therapies to antibiotics. This study aimed to investigate the inhibitory effect of four garlic derivatives on microorganisms commonly isolated in ear infections.

METHODS

The antimicrobial activities of allicin, s-allyl cysteine (SAC), diallyl disulfide (DADS), and s-allyl mercaptocysteine (SAMC) were investigated on standard strains of commonly isolated microorganisms using the broth microdilution method. The test strains were selected among the microorganisms responsible for chronic suppurative otitis media and otitis externa. These microorganisms were , and .

RESULTS

Minimum inhibitory concentration (MIC) values of allicin and SAC ranged from 0.125 to 20 μg/mL for fermentative bacteria ( and ), 20 to 80 μg/mL for non-fermentative bacteria ( and ), 5 to 10 μg/mL for gram-positive cocci ( and ), and 40 to 80 μg/mL for yeasts ( and ). MIC values of DADS ranged from 40 to 80 μg/mL for fermentative bacteria, 40 to 160 μg/mL for non-fermentative bacteria, 40 to 80 μg/mL for gram-positive cocci, and 20 to 40 μg/mL for yeasts. The MICs of SAMC were >640 μg/mL for the tested bacteria and yeasts.

CONCLUSION

Both allicin and SAC showed antimicrobial activity against the tested microorganisms, even at low concentrations. These two derivatives may be used to treat infections in the future.