Chemical composition, antioxidant and antifungal potential of Melaleuca alternifolia (tea tree) and Eucalyptus globulus essential oils against oralCandida species

摘要

Eucalyptus globulus?and?Melaleuca alternifolia?essential oils?has been of interest to researchers because they are?traditionally used for the treatment of fungal infections and especially candidiasis. The?chemical composition of hydrodistilled essential oils were analyzed by gas chromatography-mass spectrometry (GC-MS), and their antifungal activity was tested against?32?Candida?strains including 15 species. The antioxidant activities (DPPH, reducing power,?and superoxide anion radical-scavenging activity)?were also investigated. Tea tree essential oil was particularly rich on?terpinen-4-ol (40.44%), gamma terpinene (19.54%) and 1,8-cineole (95.61%) and alpha-pinene (1.5%) for the?E. globulus?oil.?E. globulus?oil?was more efficient and had the best antifungal effect on oral?Candida?albicans?and?Candida?glabratastrains comparing to the results obtained with Amphotericin B. Even at low concentrations, these oils drastically impair the maximum yield and growth rate of both?C. albicans?and?C. glabrata?on YPD medium. The Tea Tree essential oil displayed the highest DPPH scavenging ability with the lowest IC50?value?(IC50, 12.5 μg/ml), the greater reducing power and bleaching of β-carotene?(EC50, 24 μgml-1?and IC50, 42 μgml-1, respectively)?as compared to?E. globulusoil and BHT.?These findings support the interest of?E. globulus?and?M. alternifolia?essential oilsas an efficient?oral hygiene tool (anti-Candida?spp.) and as a source of antioxidant compounds.