Screening of Iranian species for antibacterial activities

The landscape of Iran includes a great range of ecological diversity and a rich flora much still unstudied for phytochemistry or bioactivity. In the present study antibacterial activity of a number of native Iranian plants species are reported, the antifungal effect's has been reported before. Some of this species are used by rural inhabitants as herbal medicine and were collected from different locations of Iran since 1994. In this study 532 species were collected from different regions of Iran. The voucher specimens were authenticated and deposited in the herbarium of the Faculty of Pharmacy, Tehran University of Medical Sciences. The air-dried plant materials were powdered and extracted in a Soxhlet extractor with methanol 80%. The extracts were tested at a concentration of 100µg/ml against organisms using Kirby Bauer method [1]. Gentamycin and methanol were used as positive and negative control, respectively. Antibacterial assay organisms were: Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus haemolyticus, Shigella sonei, Salmonella paratyphi-B, Esherichia coli, Nocardia astroides, Bacillus subtilis, Bacillus antracis, Proteus vulgaris, Pseudomonas aeroginosa, Proteus mirabilis, Vibrio cholerae, Klebsiella pneumoniae. Four species, i.e. Pistacia vera L., Cymbopogon parkerii Stapf., Myrtus communis L. and Echinophora platyloba DC showed the best antibacterial effects.The most sensitive organism was Nocardia astroides (+4, no growth) and Pseudomonas aeruginosa was the least sensitive (-, full growth). Among all tested plants the Anacardiaceae were highest ranked with 6 effective species.

Reference: [1] Baron EJ and Finedgold SM.(1990),Diagnostic microbiology, 8^th ed. Mosby Co.Philadelphia, USA