Composition and anti-fungal activity of the essential oil from Cameroonian Vitex rivularis Gurke

The chemical composition of the essential oils obtained by hydrodistillation from the aerial parts of two populations of Vitex rivularis (subgenus Vitex) collected during the flowering phase of the plants was investigated by gas chromatography and gas chromatography/mass spectroscopy. Sesquiterpene hydrocarbons were the main group in both samples, the main compound being germacrene D. This composition is markedly different from that of the other African species, with the exception of Vitex ferruginea subsp. amboniensis, which belongs to the same subgenus as V. rivularis. Minimal inhibitory concentrations (MIC) and minimal lethal concentrations (MLC) were used to evaluate the anti-fungal activity against yeasts and dermatophyte strains. The oils exhibited significant anti-fungal activity against dermatophyte strains with MIC and MLC values ranging from 0.16 to 0.64 mu L mL(-1) and 0.32 to 2.5 mu L mL(-1), respectively. For some strains, MIC values were similar to MLC values, indicating the fungicidal activity of the oils. Nevertheless, these oils showed low activity against Candida spp. strains.