Composition and Antimicrobial Activity of Leaf Essential Oils of Myrcia sylvatica (G. Mey.) DC.

Abstract

Aims: The leaves of Myrcia sylvatica have traditional use in the control of dysentery and intestinal parasites for the riparian inhabitants who live in savanna areas along the Amazon River, Brazil.   Methodology: The constituents of the oils (fresh and dried leaves) of this plant were identified by GC and GC-MS and submitted to antimicrobial analysis against diverse Gram-positive and Gram-negative bacteria, using the disk-diffusion and plate microdilution assays. Results: Sixty-three constituents were identified, with a significant predominance of sesquiterpenes belonging to the cyclization routes of the cariofilane, germacrane, cadinane and bisabolane groups, such as 1-epi-cubenol, ar-curcumene, cadalene, β-selinene, β-calacorene, cis-calamenene, ar-turmerol, muskatone, δ-cadinene, and cubenol. Based on the results, the oils can be considered bactericidal for Bacillus cereus and Staphylococcus aureus (0.2 ul/ml and 2.5 ul/ml, respectively) and bacteriostatic for Staphylococcus epidermidis and Enterococcus faecalis (20.0 ul/ml, for both), all Gram-positive bacteria. The oils were not active for Gram-negative bacteria and yeasts tested. Conclusion: The oil of Myrcia sylvatica could be used in pharmaceutical formulations to control resistant bacteria strains or to prevent food spoilage, individually or in combination with traditional antibiotic products.