No abstract

Punica granatum L. (pomegranate) is known popularly by its nutritional values and healthy benefits. The current study is aimed the evaluation of antibacterial effects of Punica granatum fruit extracts that cultivated in Algeria against environmental and clinical isolates of β-lactamase producing methicillin resistant Staphylococcus aureus (MRSA) and extended-spectrum beta-lactamase ESBL-producing Enterobacteriaceae by using agar diffusion methods and minimum inhibitory concentration (MIC)-determination. Moreover, the extracts were investigated for their phenolic content by the Folin-Ciocalteu method. The quantitative assays of total polyphenols revealed a richness of the different pomegranate extract in polyphenols, peel and seed ethanol extracts contain the highest values (880.06 ± 11.2 mg GAE/100 g and 1160.1 ± 45.20 mg GAE/100 g, respectively). Flavonoid contents were high in both of acetone, ethanol extracts of peel, followed by ethanol, and acetone extracts of juice.  According to the disc diffusion data, all phenolic extracts had a bacterial inhibitory effect against all extended-spectrum beta-lactamase ESBL-producing Enterobacteriaceae with a strong inhibitor with MIC 512 g/mL strength. The pericarp extract is particularly effective against Escherichia coli, Citrobacter freundii, and Klebseilla pneumoniae. However, the extract Punica granatum (pericarp and juice) revealed broad-spectrum antibacterial activity with an inhibitory diameter zone size of 11 0.9 mm to 29 1.12 mm against β-lactamase generating methicillin resistant Staphylococcus aureus (MRSA) species.These results were similar in both of agar diffusion and MIC methods. From the above study, it can be concluded that Algerian pomegranate extracts possess remarkable antibacterial activity. This result could be related to the presence of bioactive metabolites in this fruit. Therefore, intensive future studies should be performed to characterize the antibacterial components that are behind for this biological property.