and Rosna Mat Taha

In the present study essential oil compositions from leaves, stems and immature flowers of Eucalyptus camaldulensis Dehnh. from Malaysia and their cytotoxicity effects were investigated. The essential oils were obtained by hydrodistillation and the composition was determined by gas chromatography-mass spectrometry (GC-MS). The cytotoxicity of the essential oils was evaluated by MTT assay. The oil yields of leaves, stems and immature flowers of the plant represented 1.40, 0.57 and 0.46 %, respectively, based on dry weight. Fifteen major compounds were identified represented 98.8, 97.5 and 99.5 % of the compounds in the leaves, stems and immature flowers, respectively. Monoterpenes hydrocarbons were predominant in the three oil samples. The flower oil was the highest in oxygenated monoterpenes content (19.6%). The most abundant compounds in the three essential oils were γ-terpinene, as a principal oil component (57.4–72.5%) followed by o-cymene (14.6–26.3%) and terpinen-4-ol (6.6–16.2%). E. camaldulensis leaves essential oil demonstrated cytotoxic effects in three tested cancer cell lines; WEHI-3, HT-29 and HL-60. WEHI-3 was the most sensitive with IC50 16.1. The essential oil exhibited less cytotoxic effects in HT-29 and HL-60 cells (IC50=50.5 and 42.1, respectively). Also, it exhibited a weak cytotoxic effec