A promising peptide antibiotic from Terfezia claveryi aqueous extract against Staphylococcus aureus in vitro.

The antimicrobial activity of aqueous and methanolic extracts, as well as partially purified proteins extracted from Terfezia claveryi aqueous extract were investigated against Staphylococcus aureus in vitro. A 5% aqueous extract inhibited the growth of S. aureus by 66.4%, while a methanolic extract was ineffective. Partial protein purification of the aqueous extract using ammonium sulphate precipitation revealed that antimicrobial activity was within the third fraction. This fraction was then subjected to gel filtration using Sephadex G-100. Two peaks were obtained. Peak one possessed higher antimicrobial activity. This peak was then subjected to ion exchange chromatography using DEAE Sephadex. Only peak 4 from the six peaks obtained showed a slight antimicrobial activity. Antimicrobial activities of the aqueous extract and the fractions that showed antimicrobial activity were compared with reference antibiotics. Copyright 2004 John Wiley & Sons, Ltd.