Facile encapsulation of thymol within deamidated zein nanoparticles for enhanced stability and antibacterial properties

Thymol is one of the main essential oils derived from oregano with wide-ranging potential applications, such as antioxidation, anti-inflammation, and antibacterial properties. However, its low water solubility and bioavailability, as well as poor stability, have severely restricted its practical applications. Herein, deamidated zein nanoparticles loaded with thymol (DZTNPs) have been successfully prepared using the antisolvent precipitation approach. Particularly, a common alkaline deamidation method is used to pretreat zein as the particle precursor. Scanning electron microscopy, dynamic light scattering, zeta potential measurement, X-ray diffraction and differential scanning calorimeter have been used to characterize the resultant DZTNPs. It is worth noting that after freeze-drying, deamidated zein nanoparticles loaded with thymol have good redispersibility and physical stability stored at 4 °C. Furthermore, the as-prepared DZTNPs have greater antibacterial efficacy against E. coli and S. aureus than unencapsulated thymol for a longer period of time. Therefore, this study provides a viable vehicle for delivering hydrophobic active compounds, which is of significance in the application of food, cosmetics and pharmaceutics. Deamidated zein nanoparticles loaded with thymol are prepared by an antisolvent precipitation process, which have good dispersion stability and re-dispersibility after freeze-drying, as well as a better antibacterial performance than unencapsulated thymol. [Display omitted]