Chemical and biological evaluation of the essential oils of different <i>Melaleuca</i> species

Abstract

Abstract The essential oils of the fresh leaves of M. ericifolia , M. leucadendron , M. armillaris and M. styphelioides were isolated by a hydrodistillation method and analysed by a gas chromatography/mass spectrometry (GC/MS) technique. The essential oil of M. ericifolia contained methyl eugenol (96.84%) as a major constituent, whereas M. leucadendron was rich in 1,8‐cineole (64.30%). The essential oil of M. armillaris was rich in 1,8‐cineole (33.93%) followed by terpinen‐4‐ol (18.79%), whereas M. styphelioides was rich in caryophyllene oxide (43.78%) and (‐) spathulenol (9.65%). The essential oils of these species possessed antimicrobial and antifungal activities. M. ericifolia exhibited the highest inhibitory effects against Bacillus subtiles and Aspergillus niger . The antiviral activities of the essential oils against Herpes simplex virus type 1 (HSV‐1) were studied in African green monkey kidney cells (Vero) by a plaque reduction assay. The volatile oil of M. armillaris was more effective as a virucidal (up to 99%) than that of M. leucadendron (92%) and M. ericifolia (91.5%). The effects of the essential oils on the antioxidant system status in carbon tetrachloride treated animals were studied. The essential oil of M. armillaris exhibited a marked antioxidant effect, it improved vitamin E, vitamin C and superoxide dismutase parameters so it can be used as a free radical suppressor. Copyright © 2004 John Wiley &amp; Sons, Ltd.