Melaleuca teretifolia Chemovars: New Australian Sources of Citral and 1,8-Cineole

Abstract

The essential oil of the previously un-investigated leaves and twigs of Melaleuca teretifolia Endl. (Myrtaceae), growing wild in Western Australia, was investigated by GC and GC/MS. One oil, which yielded 0.2% on a fresh weight basis, was found to be rich in 1,8-cineole (84.0%), with α-pinene (1.8%), β-pinene (1.2%), limonene (3.1%), terpinen-4-ol (1.8%) and α-terpineol (3.3%) as the only other significant constituents. The lemon form gave a much higher yield (1.5%) of an oil rich in neral (29.1%), geranial (38.8%), and myrcene (9.8%), with significant concentrations of limonene (1.0%), citronellal (1.0%), terpinen-4-ol (3.4%), geraniol (2.1%), nerol (1.1%), (Z)-isocitral (1.6%) and (E)-isocitral (2.4%). This form has the potential to compete with commercial citral oils.