Essential Oils from Colombian Plants: Antiviral Potential against Dengue Virus Based on Chemical Composition, In Vitro and In Silico Analyses

Abstract

Currently, there are no therapies to prevent severe dengue disease. Essential oils (EOs) can serve as primary sources for research and the discovery of phytomedicines for alternative therapy. Fourteen EOs samples were obtained by distillation from six plants used in Colombian folk medicine. GC/MS analysis identified 125 terpenes. Cytopathic effect (CPE) reduction assays revealed differences in antiviral activity. EOs of Lippia alba, citral chemotype and carvone-rich fraction; Lippia origanoides, phellandrene chemotype; and Turnera diffusa, exhibited strong antiviral activity (IC50: 29 to 82 µg/mL; SI: 5.5 to 14.3). EOs of Piper aduncum, Ocimum basilicum, and L. origanoides, carvacrol, and thymol chemotypes, exhibited weak antiviral activity (32 to 53% DENV-CPE reduction at 100 µg/mL; SI > 5.0). Cluster and one-way ANOVA analyses suggest that the strong antiviral activity of EOs could be attributed to increased amounts of non-phenolic oxygenated monoterpenes and sesquiterpene hydrocarbons. Docking analyses (AutoDock Vina) predicted binding affinity between the DENV-2 E protein and terpenes: twenty sesquiterpene hydrocarbons (−8.73 to −6.91 kcal/mol), eight oxygenated monoterpenes (−7.52 to −6.98 kcal/mol), and seven monoterpene hydrocarbons (−7.60 to −6.99 kcal/mol). This study reports for the first time differences in the antiviral activity of EOs against DENV, corresponding to their composition of monoterpenes and sesquiterpenes.

Comparative Virucidal Activities of Essential Oils and Alcohol-Based Solutions against Enveloped Virus Surrogates: In Vitro and In Silico Analyses

“…Farnesol and α-cadinol formed hydrogen bonds, the first with Gyl190, Leu191, and His282, and the second with Thr48 and Tyr137. Twenty compounds that bind to E were also identified in a previous study on the anti-DENV activity of EOs from other Colombian plant species [ 25 ]. Table 6 presents the EO compounds that docked DENV-2 E identified in this study.…”

“…In silico and in vitro evidence suggests that sesquiterpene hydrocarbons and oxygenated monoterpenes in specific ratios may account for the antiviral action of the EOs [ 11 , 12 , 13 ]. Recently, we documented a variation in the anti-DENV effect related to variation in oxygenated monoterpene content [ 25 ]. We also documented [ 35 ] a better in vitro anti-DENV effect of trans -β-caryophyllene and geranyl acetate compared to p -cymene, limonene, and neral, all of which were identified in the test EO blend.…”

“…The analysis of the EO blend was performed by gas chromatography using mass spectrometric (GC/MS) and flame ionization detection (GC/FID) systems. Previous studies described the conditions of the process and data analysis [ 25 , 42 , 43 ]. Before the analysis, the EO blend was dissolved in dichloromethane (1 mL).…”

“…Following 1 h of incubation at 37 °C, the solution was discarded by washing and the cells were overlaid with fresh culture medium and incubated for 72 h at 37 °C and 5% CO 2 . Next, the cell viability was determined by staining with crystal violet, as in a previous study [ 25 ]. Briefly, 100 µL of 0.05% crystal violet solution was added to cells for 20 min at room temperature.…”

“…Structures of chemical constituents of the EO blend were retrieved from the PubChem ( (accessed on 13 April 2023)) database. The preparation of the target and ligands and molecular docking analyses were carried out using AutoDock Vina (Version 1.5.6, La Jolla, CA, USA), as described in a previous study [ 25 ]. The optimized protein structure was saved in the PDBQT file format for docking analysis.…”