Synergistic effect of Murraya koenigii and Telfairia occidentalis aqueous leaf extract on some bacteria

Abstract

The phytochemical and antibacterial properties of aqueous leaf extract of Murraya koenigii and Telfairia occidentalis and their synergy were determined against five bacterial isolates: Klebsiella pneumoniae,  Escherichia coli, Bacillus cereus, Staphylococcus aureus and Shigella dysenteriae. Saponins, flavonoids,   sugar terpenoids,  alkaloids, steroids, glycosides and tannins were detected. Antibacterial activity was   determined by the disc diffusion method. Larger zones of inhibition were observed for M. Koenigii extract than  T. occidentalis extract, and larger zones of inhibition were observed by their synergy than on their separate  use. Synergistic antibacterial activity of the extract ranged from 0 mm to 20.0 ± 0.03 mm, zone of inhibition of M. koenigii extract ranged from 0 mm to 16.0 ± 0.03 mm while that of T. occidentalis ranged from 0 mm to 12.0 ± 0.30 mm. The minimum inhibitory concentration (MIC) and minimum  bactericidal concentration  (MBC) of the two separate extracts and their synergy were also evaluated.  These ranged from 62.5 mg/ml to 500 mg/ml for M. koenigii, 62.5 mg/ml to 500 mg/ml for T. occidentalis and 31.25 to 500 mg/ml for their  synergy (least MIC to highest MBC). The test organisms were assessed for their antibiotic susceptibility  pattern and were observed to be multi-drug resistant. The synergy  showed higher zone of inhibition against the test bacteria than the separate extracts and the standard antibiotics. It is therefore, recommended to use the synergy to treat infections caused by the test organisms.

Keywords: Synergy, Telfairia occidentalis, Murraya koenigii, Antimicrobial activity, Aqueous extract