The numerous health benefits associated with the use of plants in traditional medicine can be linked to secondary metabolites in the products obtained through the hydrodistillation process, such as hydrolates and essential oils (EOs). This study aimed to assess the chemical profile and the antioxidant, antimicrobial, cytotoxic, and anti-inflammatory activities of two hydrodistillation products obtained from four plants belonging to two distinct families: chamomile (Matricaria chamomilla), purple coneflower (Echinacea purpurea), conehead thyme (Thymbra capitata), and basil (Ocimum basilicum). The EOs were found to be more effective than hydrolates in inhibiting microorganisms’ growth, registering MIC values equal to or higher than 50% (v/v), except for T. capitata. Only T. capitata demonstrated the ability to reduce NO levels with both hydrolate and EO. Moreover, it inhibited the cell growth of RAW 264.7, 3T3, and HaCaT lines at the tested concentrations. In contrast, O. basilicum EO did not affect the cell proliferation of the tested cell lines in concentrations below 0.063% (v/v) and showed a significant reduction in the macrophage NO production at all concentrations. Thus, EOs showed a superior biological activity than hydrolates. In particular, O. basilicum EO was found to be a promising candidate for therapeutic applications on the skin.
Valente et al. (Tue,) studied this question.