Chemical Composition and Cytotoxicity Evaluation of Lippia origanoides Kunth (Verbenaceae) Leaves Essential Oil on Human Gingival Fibroblasts

Abstract

The present study analyzed the chemical composition and evaluated the in vitro cytotoxicity of essential oil extracted from Lippia origanoides on human gingival fibroblasts. The essential oil was obtained through hydrodistillation, and the volatile compounds were analyzed by gas chromatography mass spectrometry (GC/MS). The cytotoxicity was evaluated using an MTT assay. The cells were exposed to the essential oil for 1h at concentrations ranging from 600 μg/mL to 650 μg/mL. The major essential oil components were p-cymene (27 %), γ-terpinene (11 %), carvacrol (11.8 %), (E)-methyl cinnamate (8.3 %), α-pinene (4.6 %), thymol methyl ether (5.2 %), carvacrol methyl ether (5.2 %), (E)-nerolidol (3.9 %), and 1,8-cineole (3.5 %). The cell viabilities compared to the control group were 90.33 % (600 μg/mL), 81.17 % (610 μg/mL), and 76.04 % (620 μg/mL). The viability of cells exposed to 630 μg/mL, 640 μg/mL, and 650 μg/mL was 63.01 %, 40.88 %, and 36.15 %, respectively, which indicated an increase in cytotoxic effects as the concentration increased. Lower concentrations of L. origanoides essential oil did not result in toxic effects against gingival fibroblasts.