Chemical composition and bio-efficacy of essential oils from Italian aromatic plants: Mentha suaveolens, Coridothymus capitatus, Origanum hirtum and Rosmarinus officinalis

The chemical composition, antifungal, antioxidant and cytotoxic activities of the essential oils (EOs) of mint (Mentha suaveolens), thyme (Coridothymus capitatus), oregano (Origanum hirtum) and rosemary (Rosmarinus officinalis) were investigated. The antifungal properties of the EOs were investigated against four species of Candida by a microdilution method. Cytotoxicity was tested on human keratinocyte (HaCaT) and lung cancer (A549) cell lines using the MTT test. DPPH· and ABTS·+ spectrophotometric assays and DPPH·- ABTS·+(HP)TLC-bioautographic assays were used to evaluate the antioxidant activity. The main compounds of thyme and oregano EOs were carvacrol and thymol, respectively; piperitenone oxide and γ-terpinene were the most abundant compounds of mint and rosemary EOs, respectively. All EOs showed activity against all Candida species in a range between 760 ± 290 to 3120 ± 0.0 µg/mL. Among the EOs, that of M. suaveolens showed a stronger cytotoxic activity on HaCaT cells. Thyme, oregano and rosemary EOs exhibited important antioxidant activities by ABTS·+ assay compared with trolox.