Study on the antibacterial and antioxidant activities of Punica granatum (pomegranate) peel extracts

Abstract

This study presents the antimicrobial and antioxidant activities of different extracts from the peel of Punica granatum fruit against various standard microorganisms. Three P. granatum peel extracts were prepared with ethanol, methanol, and water, using standard protocol, followed by their qualitative phytochemical analysis. Antibacterial and antioxidant activities of P. granatum peel extracts against Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi, and Staphylococcus aureus were tested. The phytochemical test of P. granatum peel extracts revealed the presence of therapeutic agents such as tannins. The highest antibacterial activity of the ethanolic P. granatum extract was against S. aureus, the methanolic extract against E. coli and aqueous extract against P. aeruginosa, while all the three extracts had the lowest antibacterial activity against S. typhi. The highest MIC (Minimum Inhibitory Concentration) and MBC (Minimum bactericidal concentration) were attained by the aqueous and ethanolic extracts whereas the lowest was shown by the methanolic extract, against different bacterial strains. Also, the highest antioxidant activity shown by the ethanolic extract was at 500µg/ml, 400 µg/ml in case of methanolic extract, and 200 µg/ml in case of aqueous extract. Despite being a byproduct, P. granatum (pomegranate) peel has significant potential as a source of bioactive compounds with important health benefits. The type of solvent used can significantly affect the extract's chemical profile and biological activity, as the relative and absolute concentrations of the extracted compounds play a crucial role in determining their bioactivity.