Essential Oils from Schinus Species of Northwest Argentina: Composition and Antifungal Activity

The composition of the essential oils from leaves (Sal) and fruits of S. areira (Saf), and fruits of S. fasciculatus (Sff) and S. gracilipes (Sgf) were analyzed by GC/MS. The major compounds identified were sabinene (26.0±0.5%), bicyclogermacrene (14.5±0.4%), and E-citral (6.7±0.2%) in Sal oil, limonene (27.7±0.7%), sabinene (16.0±0.5%), β-phellandrene (14.6±0.8%) and bicyclogermacrene (8.1±0.2%) in Saf oil, sabinene (22.7±0.6%), α-phellandrene (18.7±0.3%), β-phellandrene (15.7±0.4%), and bicyclogermacrene (8.1±0.2%) in Sff oil and β-pinene (25.4±0.8%), α-pinene (24.7±0.7%), and sabinene (13.6±0.4%) in Sgf oil.The antifungal activity of the four oils was evaluated on strains of Fusarium verticillioides and F. graminearum, and the results compared with the effect of epoxyconazole, pyraclostrobin and thyme oil. The Sff oil had the highest antifungal activity among the Schinus oils tested, with MIC 100 (F. graminearum) = 6 ‰ and MIC 100 (F. verticillioides) = 12 ‰. A principal component analysis suggests that 9 constituents (α-thujene, α-terpinene, p- cymene, γ-terpinene, terpinolene, 1-terpineol, α-calacorene, α-phellandrene, and terpinen-4-ol) explain the higher antifungal effect of Sff. The MIC 100 s of Schinus oils were on average 30-60 and 8.5-17 fold lower than those obtained for thyme oil on F. verticillioides and F. graminearum, respectively. In the case of commercial fungicides, their MIC 100 s were three orders of magnitude lower than those of Schinus oils. The last ones showed an additive interaction when assayed in mixtures with the commecial fungicides and thyme oil. The results suggest that the doses of fungicides required for control of the Fusarium species can be reduced when they are assayed in mixtures with the Schinus oils.Fil: Sampietro, Diego Alejandro. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Estudios Vegetales. Cátedra de Fitoquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; ArgentinaFil: Belizan, M. M. E.. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Estudios Vegetales. Cátedra de Fitoquímica; ArgentinaFil: Terán Baptista, Zareath Pamela. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Estudios Vegetales. Cátedra de Fitoquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; ArgentinaFil: Catalan, Cesar Atilio Nazareno. Universidad Nacional de Tucuman. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Organica. Cátedra de Química Organica Ii; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentin