Leaf Essential Oil from Three Exotic Mytaceae Species Growing in the Botanical Garden of Rio de Janeiro, Brazil

Abstract

The leaf essential oils of three Myrtaceae species: Melaleuca leucadendra, Lophostemon confertus and Ugni molinae, non-native to Brazil and growing in the Rio de Janeiro Botanical Garden, were obtained by hydrodistillation and analyzed by GC and GC-MS. Oil yields from fresh leaves were 0.76%, 0.08%, and 0.04%, respectively. Sixty-seven percent of M. leucadendra oil was made up of monoterpenes, wherein 1,8-cineole was largely predominant (49%), followed by α-terpineol (7.6%) and terpinen-4-ol (4.3%). The sesquiterpene profile was characterized by a significant amount of viridiflorol (29%). Oil from L. confertus was 42% monoterpenes; the most predominant constituents being α-pinene (20.8%) and α-thujene (7.1%). Total sesquiterpenes (55.4%) comprised spathulenol (28%), globulol (14%), and aromadendrene derivatives (8.5%) as the main species. U. Molinae oil was exclusively composed of sesquiterpenes, with a predominance of β-elemene (44%) followed by β-caryophyllene (7.1%), and