Chemical characterization of essential oils from Drimys angustifolia miers (Winteraceae) and antibacterial activity of their major compounds

Abstract

Essential oils have been extensively studied in recent years as a natural source of new antimicrobial agents. In this work, essential oils of leaf and branch from Drimys angustifolia growing in Southern Brazil were obtained by hydrodistillation and analyzed by gas chromatographies with flame ionization detector (GC-FID) and with mass spectrometer (GC-MS). Drimenol and bicyclogermacrene were isolated by column chromatography from branch and leaf essential oils, respectively. Oils, isolated compounds and combinations of them were assayed against Gram-(+) and Gram-(-) bacteria. The oils showed to be more active against Bacillus cereus, with minimum inhibitory concentration (MIC) 125 and 250 μg mL-1 for branch and leaf oils, respectively, strongly inhibiting bacterial growth. Bicyclogermacrene was more active then drimenol, providing a MIC value of 167 μg mL-1 against B. cereus. Synergism was not observed in any of the combinations tested.