Effect of linalool and 1,8-cineole on A549 cell apoptosis. Cells were exposed to ethanol 0.2% (Control), linalool 1.0 (LN 1) and 2.0 (LN 2) mM, 1,8-cineole 4.0 (CN 4) and 8.0 (CN 8) mM, or DMSO 5% (DMSO, positive control) for 48 h, and different apoptotic markers were studied. (A) Representative images of TUNEL assay performed using a commercial kit. Scale bar, 10 μm. (B) Around a total of ten to fifteen fields (200–500 cells/field) from three independent experiments were evaluated and TUNEL-positive cells were quantified. Data are presented as the mean ± SD; ∗∗∗p < 0.001. (C–D) Representative western blot of procaspase-3 and caspase-3 (C) and, procaspase-9 and PARP (D). GAPDH was used as a loading control. (E) Cell death was analyzed by trypan blue staining. Data are presented as the mean ± SD. ∗∗∗p < 0.001.