Chemical profile, antioxidant and antimicrobial effects of essential oil from the Moroccan endemic plant cladanthus scariosus (L.)

In this study, chemical profile, antioxidant potential and antimicrobial interactions with conventional antimicrobials of essential oil (EO) isolated from Cladanthus scariosus aerial parts were investigated. The EO was analyzed by GC-MS (Gas Chromatography-Mass spectrometry). Forty-three components representing 98.7% of the oil were identified. The main components were o-cymene, caryophyllene oxide, gamma-terpinene and alpha-sabinene. Furthermore, the antioxidant and antimicrobial activities against ten bacteria and two Candida strains were assessed. The results showed an interesting antioxidant effect with IC50 of 1.04 +/- 0.04 mg/mL, 0.55 +/- 0.01 mg/mL and 0.36 +/- 0.14 mg/mL, respectively, for DPPH (2,2-Diphenyl-1-Picrylhydrazyl), FRAP (Ferric-Reducing-Ability-Power), and ABTS (2-2'azinobis-3-ethylbenzothiazoline-6-sulphonate) methods. The EO exhibited a strong antimicrobial activity, especially against Methicillin-resistant Staphylococcus aureus and Candida glabrata. In combination with antimicrobials, the studied EO revealed a high synergism effect in reducing gentamicin MICs of bacterial strains by 128- to 256-fold and by 2- to 8-fold Fluconazole MICs against Candida strains.