Probing the chemical profiles and biological activities of medicinal plants is important for the discovery of new potent therapeutic products. Our study deciphers the chemical composition of the essential oils (EOs) obtained from three different flowers of Lantana camara and evaluates their antioxidant and anticancer activities. This work represents the first study of EOs obtained from this plant and is based particularly on the difference in flower color. In addition, no other reports dealing specifically with the antitumor effects of such flower-derived EOs have been described in the literature. The collected flowers, white, pink, and orange, were extracted by hydrodistillation to yield EO1, EO2, and EO3 respectively. Gas chromatography-mass spectroscopy was primarily employed to identify the existing volatile compounds in the samples. Their antioxidant activities were screened through both DPPH (2,2-diphenyl-1-picrylhydrazyl) scavenging assays and FRAP (ferric-reducing antioxidant power) assays. The antiproliferative effects were evaluated on two distinct breast cancer cell lines, MCF-7 and MDA-MB-231, and compared to a normal human breast cell line, MCF-10A, using an MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium) assay. All EOs showed notable antioxidant potential attributed to the active phytochemical compounds, with results being supported by a positive correlation between such activity and the total phenolic and flavonoid content. The most eminent, EO1, revealed a selective dose-dependent antiproliferative effect in both breast cancer cell lines, thus reflecting its potent role as an anticancer agent. We suggest that this highly selective activity is associated with the presence of bicyclogermacrene and epi-bicyclosesquiphellandrene in its chemical composition.
Keywords: Lantana camara; anticancer activity; bicyclogermacrene; chemical composition; epi-bicyclosesquiphellandrene; essential oil.