title: Screening of selected indigenous plants of Lebanon for antimicrobial activity.
abstract: The objective of this study is to test in vitro the antimicrobial efficacy of 39 water and 39 methanol extracts derived from different parts of 27 indigenous wild plant species that have been commonly used in Lebanese folk medicine. The antimicrobial efficacy was determined using the single disk diffusion method, with 10 and 20 microl load extract volume per disc. Nine test microorganisms were used namely, Escherichia coli, Proteus sp., Pseudomonas aeruginosa, Shigella dysenteria, Salmonella enteritidis, Salmonella typhi, Staphylococcus aureus, Streptococcus faecalis, and Candida albicans. Only one water extract out of 39 derived from whole plant of Alchemilla diademata showed an antimicrobial activity against Staphylococcus aureus. The percentage of test organisms that were susceptible to 10 most efficacious methanol plant extracts (20 microl/disc) were as follows: Achillea damascena whole plant (88.8%), Anthemis scariosa flower (88.8%), Cirsium sp. whole plant (88.8%), Centaurea ainetensis flowers (88.8%), Hieracium sp. whole plant (88.8%), Origanum libanoticum whole plant (99.9%), Ranunculus myosuroudes whole plant (88.8%), Nepata curviflora leaf (88.8%), Nepata curviflora stem, and Verbascum leptostychum flower (99.9%). The minimum inhibitory concentration (MIC) was determined on plant extracts that showed high efficacy against the test organisms. The chance to find antimicrobial activities was more apparent in methanol rather than water extracts of the same indigenous plants of Lebanon, with higher antimicrobial activities in 20 microl methanol extract-discs in comparison to that present in the 10 microl discs (P < 0.05).
authors.affiliation: Department of Animal Science, Faculty of Agricultural and Food Sciences, American University of Beirut, P.O. Box 11-0236, Beirut, Lebanon. eb01@aub.edu.lb
authors.forename: Elie K
authors.initials: EK
authors.lastname: Barbour
authors.forename: Mohammed
authors.initials: M
authors.lastname: Al Sharif
authors.forename: Vatche K
authors.initials: VK
authors.lastname: Sagherian
authors.forename: Adele N
authors.initials: AN
authors.lastname: Habre
authors.forename: Rabih S
authors.initials: RS
authors.lastname: Talhouk
authors.forename: Salma N
authors.initials: SN
authors.lastname: Talhouk
mesh_terms: D000890:Anti-Infective Agents / Q000302:isolation & purification / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects / Q000254:growth & development; D002176:Candida albicans / Q000187:drug effects / Q000254:growth & development; D004353:Drug Evaluation, Preclinical / Q000379:methods; D007861:Lebanon; D008826:Microbial Sensitivity Tests / Q000706:statistics & numerical data; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology*; D018514:Plant Structures; D010946:Plants, Medicinal
chemical_list: D000890:Anti-Infective Agents; D010936:Plant Extracts