Chemical analysis and<i>in vitro</i>antiviral and antifungal activities of essential oils from<i>Glechon spathulata</i>and<i>Glechon marifolia</i>

Abstract

CONTEXT: Glechon spathulata Benth. and Glechon marifolia Benth. (Lamiaceae, Mentheae) are aromatic plants used in traditional medicine for the treatment of viral infections. OBJECTIVE: The chemical composition and antiviral and antifungal activities of Glechon spathulata and Glechon marifolia essential oils were investigated. MATERIALS AND METHODS: The oils were obtained by hydrodistillation and analyzed by GC-FID and GC-MS. Anti-herpes virus (HSV-1) activity was examined in Vero cells by yield reduction assay, in doses of 0.0095% v/v and 0.039% v/v, for G. spathulata and G. marifolia oil, respectively. Antifungal activity was carried by the broth microdilution method, in oil concentrations that ranged from 5.2 to 500 µg/mL. RESULTS: β-Caryophyllene (14.2% and 32.2% for G. spathulata and G. marifolia, respectively) and bicyclogermacrene (17.1% and 16.5%, respectively) were the major components of both oils. At noncytotoxic concentrations of the essential oils, the viral titer was reduced by up to 2 log10 for KOS and VR-733 strains. The antifungal activity was observed against Trichophyton rubrum (MIC 10-83 µg/mL) and Epidermophyton floccosum (MIC 83-500 µg/mL). The oil of G. spathulata exhibited activity against the three strains tested (KOS, VR733, and 29-R), whereas G. marifolia oil was active against two strains, KOS and VR733. DISCUSSION AND CONCLUSION: The chemical composition for G. spathulata and G. marifolia essential oils is very similar. The oil of G. spathulata can be promising as a new antifungal agent against dermatophytes. The findings add important information to the biological activity of Glechon species essential oils, specifically its antiviral and antidermatophytic properties.