Antifungal and anti-inflammatory potential of Lavandula stoechas and Thymus herba-barona essential oils

Lavandula L. and Thymus L. comprise several relevant species for the food, cosmetic, perfumery and pharmaceutical industries. Considering the traditional medicinal use of L. stoechas and T. herba-barona and the lack of scientific studies on their biological activities, the present study was designed to elucidate the composition and antifungal activity of their essential oils against fungi responsible for human infections as well as the anti-inflammatory potential and their cytotoxicity on a macrophage cell line. Moreover, the antifungal activity against fungi responsible for food contamination is also reported.Flowering parts of the plants were submitted to hydrodistillation in a Clevenger-type apparatus and the oils were analysed by GC and GC-MS. The minimal inhibitory and minimal lethal concentrations of the oils against fungi strains were determined using a macrodilution broth method. For the anti-inflammatory activity, an in vitro model of lipopolysaccharide-stimulated macrophages was used and the inhibition of nitric oxide production quantified. Assessment of the oils cytotoxicity was performed using the MTT reduction assay.L. stoechas essential oil was rich in fenchone (37.0%) and camphor (27.3%) while T. herba-barona oil showed high amounts of two phenols, carvacrol (54.0%) and thymol (30.2%). The latter was the most active oil against the tested fungi but evidenced high cytotoxicity on macrophages. L. stoechas was active against dermatophyte strains and showed potential anti-inflammatory activity at concentrations without affecting cell viability.These results support the use of L. stoechas in the development of phytopharmaceuticals or food supplements/nutraceuticals for the management of dermatophytosis and/or inflammatory-related diseases. Regarding T. herba-barona, it can be used as a preservative in storage products, due to its ability to inhibit Aspergilllus growth.