Total Phenolic and Flavonoid Contents, Antioxidant and Antimicrobial Activity of Nepeta binaludensis Jamzad Extracts

Total phenolic and flavonoid contents in different extracts of Nepeta binaludensis Jamzad aerial parts were evaluated by colorimetric methods and the best results were found in 50% hydro-methanol extract with total phenolic (4.42 ± 0.0014 mg of gallic acid/g of dry mass of plant) and flavonoid (0.8 ± 0.0009 mg of quercetin/g of dry mass of plant) contents. Antioxidant activity of the extracts were also evaluated using 1,1-diphenyl-2-picrylhedrazyl (DPPH) assay. The best result was found in 50% hydro-methanol extract (the half-maximal inhibitory concentration IC₅₀ = 3.0 mg/mL). A good correlation between the radical scavenging activity and total phenolic and flavonoid contents of the extracts was observed. Antimicrobial activity of 50% hydro-methanol and ethyl acetate extracts of the aerial parts of N. binaludensis were also evaluated on four different bacteria and a fungus in the current study. Considerable antibacterial activity against Staphylococcus aureus (4.0 mg/mL) and Streptococcus pyogenes (4.0 mg/mL) were observed for ethyl acetate extract in comparison with the other samples.