Essential oils (EOs) are aromatic oily liquids that have some biological properties such as antioxidant and antimicrobial activities. The nanoencapsulation of these oils in drug delivery systems have been proposed due to their capability of improving the solubility, stability and bioavailability of them by maintenance of therapeutic drug blood levels. In this study encapsulation of thyme essential oil in nano-niosomes and evaluation of its total phenolic contents and antioxidant properties were evaluated. Nano-niosomes containing thyme essential oil were prepared by thin film hydration method using span20 and cholesterol and were characterized for their size, poly dispersity index, zeta potential, encapsulation efficiency and morphology. Then the total phenolic contents and antioxidant activity of free and nano-niosomal essential oil was studied. The results show that particle size was about 83 nm and poly dispersity index was 0.226. The encapsulation efficiency of essential oil was 17% when appropriate formulation is used. We observed that total phenolic contents and antioxidant activity of EO was significantly increased after encapsulation. Nano encapsulation effectively enhanced beneficial properties of thyme essential oils such as total phenolic contents and antioxidant properties.
