Wound Healing Effects from 3 Hypericum spp. Essential Oils

Hypericum species have a long-term use as wound healing agents, with the most common preparation being the infused oil from the aerial parts. It contains naphthodianthrones, phloroglucinols, and essential oil. An extensive literature survey shows that, unlike napthodianthrones and phloroglucinols, essential oils from Hypericum spp. have not yet been evaluated for their wound healing efficacy. The present study aims to assess the wound healing efficacy of essential oils from H. perforatum, a plant recognized in European Pharmacopoeia for having wound healing properties, as well from 2 other Hypericum species commonly used in Greece as wound healing agents since classical antiquity, namely, H. empetrifolium and H. triquetrifolium. So far, only the wound healing effects of Hypericum oil are known, which is a different herbal preparation containing nonvolatile compounds, while the essential oils under investigation contain only volatile constituents. The essential oils were subjected to GC-MS analyses. Wounds were created on the upper back of hairless SKH-hr1 mice. Healing was evaluated by clinical, histopathological, and biophysical assessment. The essential oils showed a significantly faster wound healing rate in comparison to the controls and the vehicle-treated groups. H. empetrifolium possessed the most significant healing properties while for H. perforatum and H. triquetrifolium skin inflammation persisted. The essential oils from Hypericum spp. showed promising results as wound healing agents and are likely to contribute to the wound healing efficacy of the Hypericum preparations. H. empetrifolium, being the most potent anti-inflammatory and wound healing agent, confirms the traditional use of this plant in Greece for wounds and skin inflammations.