Abstract

The species of the genus Citrus (Rutaceae) have been widely used in traditional medicine. In this study, the essential oil was extracted from the leaves of Citrus aurantium and its cytotoxicity effect on six tumor cell lines and a normal cell line was studied. Furthermore, antioxidant potential of the oil was tested by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay, hydrogen peroxide scavenging and reducing antioxidant power methods. The composition of the essential oil was also analyzed by GC–MS. Results indicate 41 components that represented 97.81% of the total oil. The major components were limonene, linalool and trans-beta-ocimene. In addition, the essential oil also exhibited strong antioxidant activity. The IC₅₀ of the oil in DPPH assay, H₂O₂ scavenging and reducing antioxidant power were 1040 ± 0.9, 140 ± 1.5 and 1580 ± 1.03 µg /ml, respectively. The essential oil also had marked cytotoxicity against the all tumor cell lines, with the highest activity on Jurkat and HL60.

Key words: Citrus aurantium, essential oil, chemical composition, cytotoxicity, antioxidant effect.