Antimicrobial Activity Of Punica granatum (Pomegranate), A Middle Eastern Traditional Medicinal Plant

Each year, hundreds of millions of antibiotics are administered to people and to animals. The overuse and misuse of antibiotics has led to a growing public health crisis—antibiotic resistance. This crisis calls for new antimicrobial compounds to combat resistant pathogens. Plants used by traditional healers may provide these new antimicrobics. Punica granatum (pomegranate) has been used to treat skin wounds in Middle Eastern and Asian medicine. Our aim is to explore the antimicrobial properties of P. granatum seeds against bacteria and fungi. Acetonic, isopropanolic, and aqueous extracts of pomegranate seeds (250 mg/mL) were screened against methicillin-resistant Staphylococcus aureus (MRSA), Mycobacterium phlei, Enterococcus faecalis, and Streptococcus mutans (gram-positive) bacteria; Escherichia coli (gram-negative) bacteria; and Aspergillus niger (fungus) using agar diffusion assays. The gram-positive bacteria, including MRSA, were inhibited by isopropanolic extracts. Using serial dilutions, the minimal inhibitory and bactericidal concentration against Sta. aureus is 125 mg/mL. We tested the effect of temperature (ranging from 5-50°C) on the extracts’ antimicrobial properties. The greatest inhibition was seen at 25°C. Chromatography will be used to isolate the antimicrobial component of the extract. These findings and further studies may provide an alternative antimicrobial against antibiotic-resistant gram-positive bacteria.