title: Antifungal Activity of the Essential Oils of Callitris neocaledonica and C. sulcata Heartwood (Cupressaceae).
abstract: Mortality due to fungal infections has increased substantially, becoming a worldwide problem in public health. As a contribution to the discovery of new antifungal agents, the properties of the heartwood essential oils of two trees growing in New Caledonia, Callitris neocaledonica and C. sulcata (Cupressaceae) were investigated. The essential oils extracted by hydrodistillation were characterized by GC-FID and GC/MS analyses. From C. neocaledonica oil, 31 constituents were identified, representing 97.0% of the total oil composition, which was mainly constituted by oxygenated sesquiterpenes (88%). Among them, guaiol (1; 30.2%), bulnesol (2; 12.5%), α-eudesmol (3; 10.5%), β-eudesmol (4; 10.5%), γ-eudesmol (10.2%), and elemol (4.9%) predominated. The chemical composition of C. sulcata oil, from which 39 constituents were identified (96.8% of the total oil composition), showed some similarities with that of C. neocaledonica oil. The major constituents were also oxygenated sesquiterpenes, accounting for 78.5% of the oil, amongst them, mainly compounds 1 (16.1%), 3 and 4 (9.7% each), as well as 2 (7.4%). The antifungal activity of the oils against clinical isolates of four dermatophytic fungi (Trichophyton mentagrophytes, T. rubrum, Microsporum canis, and M. gypseum) and six yeasts (Candida albicans, C. parapsilosis, C. glabrata, C. krusei, Cryptococcus neoformans, and Cryptococcus gattii) was tested by determining minimum inhibitory concentrations (MICs) using the microdilution method. The best antifungal activities of the C. neocaledonica and C. sulcata oils were obtained against C. krusei (MICs of 3.9 and 0.975 μg/ml, resp.). These MIC values were similar to those of the reference drugs itraconazole and fluconazole (1.0 and 0.5 mg/ml, resp.). The oils were also subjected to a screening for their possible DPPH(.)  (2,2-diphenyl-1-picrylhydrazyl) radical-scavenging activity. C. neocaledonica essential oil was more active than C. sulcata oil (93.3 vs. 32.2% DPPH(.)  scavenged at 250 μg/ml).
authors.affiliation: UMR217, Laboratoire Substances Naturelles Terrestres & Savoirs Traditionnels (SNT&ST), IRD, BP A5, 98848, Nouméa, Nouvelle-Calédonie.
authors.forename: Jean
authors.initials: J
authors.lastname: Waikedre
authors.forename: Carmen I
authors.initials: CI
authors.lastname: Vitturo
authors.forename: Ana
authors.initials: A
authors.lastname: Molina
authors.forename: Phellipe Norato Estrela Terra
authors.initials: PN
authors.lastname: Theodoro
authors.forename: Maria
authors.initials: M
authors.lastname: do Rosário Rodrigues Silva
authors.forename: Laila Salmen
authors.initials: LS
authors.lastname: Espindola
authors.forename: Alexandre
authors.initials: A
authors.lastname: Maciuk
authors.forename: Alain
authors.initials: A
authors.lastname: Fournet
mesh_terms: D000935:Antifungal Agents / Q000737:chemistry* / Q000494:pharmacology; D003883:Arthrodermataceae / Q000187:drug effects; D002175:Candida / Q000187:drug effects; D029779:Cupressaceae / Q000737:chemistry*; D016166:Free Radical Scavengers / Q000737:chemistry; D008401:Gas Chromatography-Mass Spectrometry; D008826:Microbial Sensitivity Tests; D009822:Oils, Volatile / Q000737:chemistry* / Q000494:pharmacology; D012717:Sesquiterpenes / Q000737:chemistry
chemical_list: D000935:Antifungal Agents; D016166:Free Radical Scavengers; D009822:Oils, Volatile; D012717:Sesquiterpenes