IN VITRO EVALUATION OF THE EFFECTS OF ESSENTIAL OIL EMULSIFIED SYSTEMS ON THE CENTRAL NERVOUS SYSTEM

The low water solubility, high volatility and instability of essential oils limit the studies on their formulations. It is known that these problems are managed by the formulation of essential oils nanoemulsions. In this study, in vitro anti-inflammatory and anticholinesterase effects on the central nervous system (CNS) were investigated by forming nanoemulsions of Rosmarinus officinalis L. (Rosemary, Lamiaceae) and Coriandrum sativum L. (Coriander, Apicaeae) essential oils and their combinations. In this study, chemical contents of rosemary and coriander essential oils were determined by GK-AID and GK/KS methods. O/W emulsions were obtained by water titration method. Characterization studies were carried out by measuring the droplet size, PDI, zeta potential and turbidity of the emulsions. Resistance to centrifugation, freezing and heating was determined as rapid stabilization tests. In vitro 5-lipoxygenase inhibition of essential oils and emulsions were determined and evaluated comparatively. Finally, in vitro anticholinesterase effects of stable nanoemulsion formulations were determined. The Pharmacopoeia complying rosemary (44.1% 1,8-cineol) and coriander (74.9% linalool) essential oils, and their resulting emulsion formulations obtained were successfully. As an overall result, no changes were observed in 5 different nanoemulsions after stability tests. In addition, the anti-inflammatory effect of coriander essential oil was increased by nanoemulsion. However, there was no significant difference in the cholinesterase inhibition effects of the oil formulations.