comparison of antibacterial activity of some of the medical plants extracts of golestan province against staphylococcus aureus

background & aim: during human history, most of infectious diseases have been cured with herbal drugs traditionally so that, nowadays, in most developing countries, herbal drugs play an important role in primal remedy. this study has been done according to the appropriate climate and biodiversity of plants in golestan province in order to investigate the antimicrobial activity of alcoholics, aqueous and boiling extracts of 23 medical plants species of golestan province on clinical and standard stains of staphylococcus aureus (mrsa and mssa) and do comparison among them and determine the appropriate plant for next studies. experimental: 23 medicinal plants were collected from their natural habitat in golestan province in north of iran. their ethanolic and aqueous extracts were obtained by percolation methods. antibacterial effects were assessed by disc diffusion method against 14 clinical and standard strains of methicillin resistant and sensitive strains of s. aureus. results & discussion: the result of antibacterial activity of these plants revealed that, ethanolic, aqueous and boiling extracts of 8, 3and 5 plants showed best effect. the ethanolic extract of artemisia herbaalba, nigella sativa, punica granatum posed the most outstanding in vitro antibacterial activity which the maximum inhibition zone was between 18-25 mm. also, the results showed that ethanolic extract had better antibacterial effect than aqueous and boiling extracts and boiling extracts had better antibacterial effects than aqueous extract. anti-staphylococcal activity of ethanolic extract of plants against mrsa was better than mssa strains. industrial and practical recommendations: the ethanolic, aqueous and boiling extract of punica granatum had the best antibacterial activity against microorganism. the result obtained from these plants might be considered sufficient for further studies.