Analysis of the chemical composition and in vitro cytotoxic activities of the essential oil of the aerial parts of Lavandula atriplicifolia Benth

Plants of the Lavandula genus have been widely used in folk and traditional medicine. The aim of this study was to evaluate the qualitative and quantitative chemical composition of the essential oil of the aerial parts of Lavandula atriplicifolia (EOAPLA) grown in Saudi Arabia and its potential cytotoxicity to cancer cell lines. The essential oil was characterized and quantified by GC–MS and GC-FID. The potential cytotoxicity of the essential oil was evaluated against colorectal (LoVo) and hepatocellular (HepG2) carcinoma cell lines by using the MTT and lactate dehydrogenase (LDH) cytotoxicity assays. A total of 36 compounds were identified that constituted 92.3% of the total oil. The chemotype of the species was dominated by C-10 massoia lactone (46.65%) as the major compound followed by oxygenated monoterpenes (28.43%). This is the first report to describe the presence of the rare compound massoia lactone in the essential oils from Lavandula species. The data revealed that EOAPLA inhibited the growth of LoVo and HepG2 cells in a dose-dependent manner. Treatment with 10 μg/mL EOAPLA for 2 days resulted in significant damage to LoVo cells in comparison with the control. In contrast to the control cells, the LoVo cells showed morphological alterations such as cytoplasmic condensation, shrinkage, and the formation of debris. Moreover, EOAPLA treatment induced apoptosis in LoVo cells since it increased the expression of caspase 3/7. The cytotoxic and anti-proliferative properties of EOAPLA make it a good candidate for treatment of various cancers.