Anticancer activity of Citrus limon (L.) Burm. f. and Citrus sinensis (L.) Osbeck essential oil and their nanoemulsions

This article presents the chemical composition, antioxidant, and anticancer activity in vitro of Citrus sinensis and Citrus limon essential oil and their nanoemulsions (NEOs). Leaves of C. sinensis and bark of C. limon were collected in the state of Maranhão, and their essential oils were extracted by hydrodistillation. The compounds present in the EOs and NEOs were identified and quantified by GC-MS. The NEOs were formulated by the phase inversion method. The antioxidant activity was performed by the elimination assays of radicals ABTS, DPPH, superoxide, hydrogen peroxide, and hydroxyl. The anticancer activity in vitro was evaluated against tissue cells: colon, lung, liver, cervix, prostate, oral, and neuroblastoma. In the EO of C. sinensis, limonene was identified as the major compound, and in the EO of C. limon also through the GC-MS assay. The NEOs of C. sinensis and C. limon obtained were stable, respectively, with a droplet size of 69.12; 71.66 nm, zeta potential -20.11; -21.55 mV, polydispersion index of 0.26; 0.28 and pH 4.88; 4,12. EOs and NEOs showed strong antioxidant activity with IC50 ranging from 6.23 to 159.02 μg/mL. They also showed significant cytotoxic activity against all cell lines used in the study, with the greatest effects against the cell line 502713 (colon), IMR-32 (neuroblastoma), Hep-2 (liver) and SiHa (cervix) with IC50 values of 1.59; 1,75; 1.91 and 2.54 μg/mL, respectively. These findings suggest that the EOs and NEOs of C. sinensis and C. limon may be alternatives for innovative therapies.