Novel antibacterial activity of Terfizia claveryi aqueous extract against clinical isolates of corneal ulcer

Abstract

Terfizia claveryi was examined for in vitro antibacterial activity using the disc diffusion, well diffusion method, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). T.claveryi exhibited excellent antibacterial activity against all clinical isolates of corneal ulcer tested, especially against Pseudomonas aeruginosa which showed the maximum antibacterial activity with mean zone of inhibition 20.33 mm at concentration of 100 mg/ml. The MIC for Staphylococcus aureus ranged from 0.040-1.250 mg/ml and MBC for Escherichia coli was 75 μl/ml. In the present study, the MIC value of the active aqueous extract were lower than the MBC values suggesting that, T. claveryi aqueous extracts were bacteriostatic at lower concentration but bactericidal at higher concentration. Also, the bacterial zone of inhibition increased with the increasing concentration of T. claveryi aqueous extract. To the best of our knowledge, this is the first report for the novel antibacterial activity of T.claveryi aqueous extract. This active compound may be used as alternative therapeutic drug for the control of corneal infections. However, further research is needed to examine its in vivo mechanism of action, toxicity, and therapeutic effect.

Key words: Bacteria, corneal infection, antimicrobials, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), Terfizia claveryi.