Acquiring infectious diseases due to resistant infectious agents leads to serious problems such as taking higher doses of antibiotics, additional treatments, lengthened hospital stay, and imposing additional costs. The aim of the current study is to study antibacterial effects of the hydroalcoholic extracts of four Iranian medicinal plants, occurring in Chaharmahal va Bakhtiari, on Staphylococcus aureus and Acinetobacter baumanii. In this experimental study, the hydroalcoholic extracts of the plants were prepared by maceration. To investigate the antibacterial effects, microdilution and determination of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were used. DMSO and distilled water were used as solvent. The MIC and MBC of Dianthus orientalis, Ziziphora clinopodioides, Euphorbia sp., and Acanthophyllum glandulosum Bunge ex Boiss. for S. aureus were derived 4, 0.5, 2, and 2 mg/ml and 16, 8, 8, and 16 mg/ml, respectively. Also the MIC and MBC of plants for A. baumanii were derived 4, 1, 0.5, and 2 mg/ml and 16, 8, 8, and 32 mg/ml, respectively. The greatest antibacterial effect was displayed by Z. clinopodioides on S. aureus. The greatest bactericidal effect on A. baumanii was exerted by the recently identified species, Euphorbia sp. These plants can serve as suitable choices to produce antibiotics to fight treatment-resistant bacteria
