Isolation of the volatile fraction from Apium graveolens L. (Apiaceae) by supercritical carbon dioxide extraction and hydrodistillation: chemical composition and antifungal activity.

Apium graveolens L. (wild celery), belonging to the family of Apiaceae, is a scaposus hemicryptophyte. Instead, the cultivate plant is an annual or biennial herb widely used as a spice and seasoning in food. A broad range of biological activities have been attributed to A. graveolens. These include antimicrobial activity, larvicidal activity, hepatoprotective activity, nematicidal and mosquito repellent potential and antihyperlipidaemic properties.In this study, the authors compare the composition of the volatile fractions of A. graveolens collected in natural populations in Portugal and Italy and evaluate their potential as antifungal agents.The composition of the volatile oils obtained by hydrodistillation and their antifungal activity are reported. The oils were analysed by gas chromatography-flame ionisation detector and gas chromatography-mass spectrometry methods and their composition were compared with that of the volatile extracts isolated by supercritical CO2. A chemical variability in the extracts depending on the origin of the plants and on the extraction method was observed. The results showed the presence of sedanenolide, neocnidilide and neophytadiene as main components. The minimal inhibitory concentration (MIC) and the minimal lethal concentration were used to evaluate the antifungal activity of the oils against Candida albicans, Candida tropicalis, Candida krusei, Candida guilliermondii, Candida parapsilosis, Cryptococcus neoformans, Trichophyton rubrum, Trichophyton mentagrophytes, T. mentagrophytes var. interdigitale, Trichophyton verrucosum, Microsporum canis, Microsporum gypseum, Epidermophyton floccosum, Aspergillus niger, Aspergillus fumigatus and Aspergillus flavus. The oil from Italy rich in neophytadiene is the more active, with MIC values of 0.04-0.64 µL mL(-1). Our results show that A. graveolens volatile extracts may be useful in the clinical treatment of fungal diseases.