摘要：Plants have been used in the treatment of many diseases from the past to the present, except for their use in the nutrition of living things and today, they are used for industrial and medical purposes. In Turkey where is rich in endemic plants, people utilize several methods to benefit from the plants, especially in the medical field. In this study, ethanol extracts of G ypsophila la ric in a Schreb, Centaurea aphrodisea Boiss, Centaurea polyclada DC and Lim oniopsis d a visii Bokhari, that are endemic plants for our country, were obtained and antibacterial and antifungal activities were investigated against eighteen bacteria and twofungus by disc diffusion method. C. aphrodisea extract got the highest antimicrobial effect at all concentration. In addition, the antimicrobial activities of the plant ethanol extracts were also analyzed with minimum inhibitory concentration (M IC) and minimum bactericidal/bacteriostatic concentration (MBC) methods. B oth Centaurea sp. showed the high antimicrobial effect at their low concentrations. The crystal violet binding method was performed to evaluate the biofilm inhibition potential of plant extracts. The best biofilm inhibition rate were obtained from G. la ric in a extract against S. infantis at a concentration of 12.5 mg/ml with a rate of 31.8%. Finally, DPPH (2,2-diphenyl-1picrylhydrazyl) method was applied to elucidate the antioxidant activity of them L. d a visii revealed the best antioxidant properties (EC50 =0.48 mg/ml). Due to the biological activities of these plant extracts, these plants might be an alternative to antibiotics and chemicals.
