In Vitro and in Silico Assessment of the Potential of Niaouli Essential Oil as a Quorum Sensing Inhibitor of Biofilm Formation and its Effects on Fibroblast Cell Viability

HIGHLIGHTS

Essential oil (EO) of Niaouli is an inhibitor on biofilm formation of P. aeruginosa.

The main components of Niaouli EO act as possible inhibitors of LasR.

The inhibition effect of these molecules on LasR is verified by molecular docking.

Niaouli EO has effects on cell viability of fibroblast cells at high concentrations.

Niaouli is a valuable essential oil for pharmaceutical applications.

Abstract

Essential oils (EO), as new bioactive compounds, have been used for pharmaceutical applications. In this study, EO of Niaouli was found to have a high content in 1,8-cineole (58.53%). Furthermore, pinene, α-terpineol, nerolidol and ledene were found to be its components with an abundance of above 2%. Niaouli EO also had effects as inhibitor of Pseudomonas aeruginosa PAO1 biofilm formation (p<0.05). In the molecular docking study, this effect was explored. The natural ligand OdDHL, the bound ligand TP-1 (Triphenyl-1), the major component 1,8-cineole and the other components with significant abundance were docked against the binding region of the LasR protein. The docking study exhibited that 1,8-cineole together with the other components investigated could inhibit LasR competitively. Its effect on cell viability was also analyzed by MTT assay. Although dose-dependent cell viability effect was observed for all hours (p<0.05), IC₅₀ value was above 100 μg/mL. Therefore, Niaouli can be assessed safely for dermatological applications because of its low toxicity on fibroblast cells and may be considered as potential quorum sensing inhibitor because of its inhibition effect on biofilm formation.

Keywords:
Biofilm; fibroblast; molecular docking; niaouli; viability