Physicochemical properties and antimicrobial efficacy of eugenol nanoemulsion formed by spontaneous emulsification

Abstract

By formulating a nanoemulsion with suitable carriers, this study strives to increase the water solubility of eugenol. This innovative approach aims to address the current limitations in solubilizing eugenol for potential applications in various industries. Eugenol is extracted from the leaves and buds of cloves, and formulating it into a nanoemulsion enhances its effectiveness, overcoming limitations in its broad-spectrum antimicrobial potential. A eugenol-loaded nanoemulsion was prepared using Tween 80 and Tween 20 surfactants via the spontaneous emulsification method. The physicochemical characteristics, long-term stability, and antimicrobial activity against a wide range of microorganisms were evaluated. Among the selected nanoemulsion formulations, those with the smallest particle sizes, measuring 95, 101, 81, and 77 nm, were identified. Additionally, all formulations exhibited a surface charge of (− 25.0 ± 1.0 mV). Compared with the solution, the eugenol nanoemulsion formulation demonstrated a reduced release rate, indicating the potential for sustained drug release. The final formulation displayed notably lower MICs (minimum inhibitory concentrations) and MBCs (minimum bactericidal concentrations) in pure oil and showed effective antimicrobial and antifungal activity against various microorganisms. Eugenol encapsulated in nanoemulsions had stronger antimicrobial effects than did either pure eugenol or nanoemulsions without eugenol. The spontaneous formation of nanoemulsions is regarded as a highly cost-effective approach that offers time and material savings, along with the production of stable nanoemulsions. This characteristic renders it particularly suitable for industrial applications necessitating high-volume production. Moreover, the antimicrobial properties associated with nanoemulsions make them appropriate for diverse therapeutic uses, including transdermal drug delivery and food preservation.