inhibitory effects of plant extracts on pseudomonas aeruginosa biofilm formation

Background: pseudomonas aeruginosa is opportunistic bacteria that cause diseases in human beings, animals and plants. it is one of the most important factors of the nosocomial infections in a wide range of patients with immunodeficiency including patients with malignant diseases, cystic fibrosis and burns. biofilm production is one of the pathogenic factors of these bacteria. objectives: the current study aimed to investigate the effects of a few plant extracts on in-vitro formation of pseudomonas aerugi- nosa biofilm. materials and methods: using the rotary system, the extracts of various plants were concentrated and prepared. standard bacterial strains were provided and growth and biofilm formation of strains were determined using the microtiter plate method. results: results showed desirable antimicrobial effects of the silver nanoparticles and plant extract on the formation of the pseu- domonas aeruginosa biofilm and the highest effect was observed in silver nanoparticles and the lowest inhibitory effects were ob- served in bucks beard and prangos ferulaceae. conclusions: medicinal plants used in the study decreased the rate of biofilm formation. since the biofilm formation is one of the pathogenic factors in mucoid strains, further studies will probably help to control the infections using the findings of the current study.