Antimicrobial activity of aqueous and methanolic extracts of pomegranate fruit skin

Objective: Punica granatum, commonly known as pomegranate, has emerged as a medicinal plant with potential antimicrobial activity. The present study was planned to evaluate this activity against both Gram positive Staphylococcus aureus (S. aureus) and negative Pseudomonas aeruginosa (P. aeruginosa) bacteria as well as against pathogenic yeast, Candida albicans (C. albicans). Material and Methods: The aqueous and methanolic extracts of pomegranate fruit skin were prepared using a Soxhalet apparatus. Antimicrobial effect of the extracts was studied and compared with commercial antibiotics using three different methods; agar dilution, cylinder plate, and disk inhibition zone techniques. Results: Both extracts showed good antibacterial activity against S. aureus and P. aeruginosa. Also the methanolic extract presented strong antifungal effect on C. albicans. The antimicrobial activities against S. aureus, P. aeruginosa and C. albicans were comparable with those of cloxacillin, gentamycin and clotrimazole, respectively. The methanolic extract was found to be more effective than aqueous one against all the tested microorganisms. Conclusion: The extracts from pomegranate fruit skin possess strong antimicrobial activity against the tested microorganisms. Therefore this plant could be an important source of new antimicrobial compounds to treat bacterial and fungal infections.