Assessment of the in Vitro Antimelanoma Potential of Lippia microphylla Cham (Verbenaceae) Essential Oil

Essential oils stand out among natural products for their complex composition, frequently described in the literature with a range of biological effects. This study evaluated the cytotoxic activity against several human cancer cell lines of essential oils extracted from the leaves of Lippia microphylla (EO-LM) Cham. (Verbenaceae). The melanoma cell line SK-MEL-28 was the most sensitive to the EO-LM, presenting an IC50 of 33.38 +/- 1.16 mu g/mL. Afterward, the effects of EO-LM on the cell cycle, induction of apoptosis, and production of reactive oxygen species (ROS) were evaluated. We stated a significant increase in the sub-G1 population, indicating apoptosis, later confirmed by an increase of SK-MEL-28 cells labeled with Annexin V-FITC and by the formation of apoptotic bodies and membrane blebs, observed by confocal microscopy. Additionally, EO-LM reduced the production of ROS, indicating antioxidant activity. Therefore, EO-LM exhibits anti-melanoma activity in vitro, suggesting its potential as an anticancer agent.