Micromeria inodora (Desf.) Benth. is most studied for the antimicrobial activity of their essential oils; nevertheless there are no reports on the phenolic compounds of this species and their antioxidant activity. In this study, aqueous and organic extracts were assayed for their antioxidant activity. The polyphenol and total flavonoid content, varied between 175.50 and 332.62 mg GAE/g extract and 65.38-86.30 mg catechin equivalent/g extract, respectively. The results of antioxidant activity have shown that all extracts reported an important activity and the ethyl acetate extract showed the stronger effect, higher than some standards molecules. Its IC50 value of scavenging DPPH is 1.5 ± 0.001 μg/mL; β-Carotene Bleaching assay (BCB) IC50 = 28.1 ± 0.001 μg/mL and the Ferric Reducing Antioxidant Power (FRAP) IC50 = 6.96 ± 0.05 μg/mL. RP-HPLCPDA analysis of phenolic compounds revealed the presence of phenolic acids and flavonoids as: gallic acid, quercetin, rutin, vanillin and naringenin.
Keywords: Micromeria inodora; RP-HPLC-PDA; antioxidant activity; flavonoid; polyphenol.