Formation, stability and antimicrobial activity of laurel leaves essential oil (Laurus nobilis L.) particles in suspension obtained by SFEE

Abstract

Laurel leaves essential oil is widely studied and valued due to its bioactive functions as antimicrobial, antifungal, antioxidant, antiviral, insecticide and food applications. Encapsulation may be an alternative for protection of their active components. Therefore, the objective of this work is to evaluate the influence of process variables of the Supercritical Fluid Extraction of Emulsions (SFEE) on encapsulation efficiency and, the innovative, on the stability of the particles in suspension (ZP), as also morphological characteristics (TEM), thermal stability (TGA) and finally, as a differential, antimicrobial activity (agar diffusion method and broth dilution test) of the SFEE particles in suspension. Spherical and massive microparticles were formed by SFEE, with encapsulation efficiency ranging from 80.0 % to 56.6 %, particle size (Dp) ranging from 200 to 1000 nm, and stability enhancement with increasing pH. Encapsulation improved the thermal stability of the particles and maintained the bacteriostatic and fungistatic activities of the laurel essential oil.