Abstract

This study aimed to characterize chemically and evaluate the cytotoxicity and antioxidant, antifungal and modulatory activities of the essential oil of Eupatorium ballotifolium, collected in the mountainous region of Meruoca in the state of Ceará. The antioxidant activity was investigated by the free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging assay and β-carotene/linoleic-acid oxidation model system. The lethality bioassay was performed using Artemia salina (brine shrimp). The evaluation of the antifungal activity in vitro was performed by broth microdilution using strains of dermatophyte fungi and yeasts. The modulatory activity assays were performed by the checkerboard technique using ketoconazole as standard. Chromatographic analysis associated with mass spectrometry showed the main constituents of E. ballotifolium essential oil were β-caryophyllene (23.59%), thymol methyl ether (12.28%), germacrene D (6.56%) and bicyclogermacrene (6.47%). The brine shrimp lethality assay demonstrated potential biological activity. The essential oil showed better antioxidant action by the β-carotene/linoleic acid assay, with IC50 value of 19.47 µg/mL for essential oil, 11.32 µg/mL for thymol and 22.83 µg/mL for carvacrol, used as test standards. The broth microdilution test demonstrated that the essential oil inhibited fungal growth of all Trichophyton rubrum strains. In the modulation activity assay against strains of Trichophyton rubrum, there was synergism of essential oil on the strains of dermatophyte fungi when combined with ketoconazole.

Key words: Compositae, Lourteigia ballotaefolia, Trichophyton rubrum, antioxidant activity, antimicrobial activity.