Phytochemical Properties and Antibacterial Effects of Salvia multicaulis Vahl., Euphorbia microsciadia Boiss., and Reseda lutea on Staphylococcus aureus and Acinetobacter baumanii

Plants have long served as a rich source of drugs. Given some microorganisms’ acquisition of resistance to the current antibiotics, there is a need for discovering new drugs. The aim of the present study was to investigate the phytochemical properties and antibacterial effects of Salvia multicaulis Vahl., Euphorbia microsciadia Boiss., and Reseda lutea against Acinetobacter baumanii and Staphylococcus aureus. In this experimental study, hydroalcoholic (ethanol 70%) plant extracts were prepared by maceration. Minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) were determined by CLSI broth microdilution and Müller-Hinton agar assay for each sample, respectively. Total phenolic content was measured by Folin-Ciocalteu colorimetric assay and expressed in terms of gallic acid equivalent and total flavonoid content by aluminum chloride colorimetric method and in terms of rutin equivalent. Findings showed that 1, 4, and 1 mg/mL were derived as MICs and 4, 16, and 8 mg/mL as MBCs for S. multicaulis Vahl., E. microsciadia Boiss., and R. lutea, respectively, against S. aureus; 2, 8, and 2 mg/mL were derived as MICs and 16, 32, and 16 mg/mL as MBCs for S. multicaulis Vahl. R. lutea, and E. microsciadia Boiss., respectively, against A. baumanii. In addition, E. microsciadia Boiss. and S. multicaulis Vahl. were found to contain the highest total phenolic and flavonoid content, respectively. The studied plants that were collected from Chaharmahal and Bakhtiari Province can be used to produce antibiotics due to their phenols and flavonoids and exert antibacterial effects on the studied bacteria.