Antibacterial activity of allicin alone and in combination with β-lactams against Staphylococcus spp. and Pseudomonas aeruginosa

Abstract

Allicin is one of the most effective compounds isolated from garlic showing antibacterial activity. Determination of MIC alone or in combination with cefazolin/oxacillin against Staphylococcus spp. or with cefoperazone against Pseudomonas aeruginosa showed that allicin alone did not have good antibacterial activity (MIC90 >512 μg/ml) but it facilitated antibacterial activity of all three β-lactams tested at subinhibitory concentrations. In the presence of 1/8 to 1/2 the MIC of allicin, the MIC90 values of cefazolin, oxicillin, and cefoperazone were reduced by 4-128, 32-64, and 8-16 fold, respectively. Thus, allicin-β-lactam combinations offer promise of clinical utility especially if synergism is demonstrated by in vivo experimental studies. © Japan Antibiotics Research Association.