Antibacterial activity of aqueous and ethanolic leaf extracts of Peperomia pellucida (l.) H. B. & K. (piperaceae) on three gram-negative bacteria isolates.

Abstract

The antibacterial activity of aqueous and ethanolic leaf extract of Peperomia pellucida was investigated on Escherichia coli, Proteus mirabilis and Pseudomonas aeruginosa using Agar-well diffusion method. Results showed that E. coli displayed the highest susceptibility in water extract (17.4mm–21.2mm) followed by P. mirabilis (12.4mm–15mm) and least in P. aeruginosa (10.2mm–12.24mm). Conversely, the ethanolic extract showed the highest inhibition in P. aeruginosa (13.4mm–19.6mm) followed by Proteus mirabilis (10.2mm–18.2mm) and the least was in Escherichia coli (0.0mm–12.2mm). The results revealed that ethanol is better than water as solvent for extraction of P. pellucida for it to show its highest inhibitory activity on Proteus mirabilis and P. aeruginosa while water is the best solvent for extraction of P. pellucida for it to show its highest inhibitory activity on E. coli.

Keywords: Antibacterial activity, Peperomia pellucida, Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa, leaf extracts