Encapsulation of essential oils from Lippia multiflora and Rosmarinus officinalis in dispersible lipid systems: process optimization and bioactivity assessment

Abstract

Essential oils (EO) from Lippia multiflora (LM) and Rosmarinus officinalis (RO) have been investigated for several applications. The antimicrobial property is of particular interest, considering the potential application for combating the resistance of microorganisms to conventional antimicrobials. However, instabilities due to thermosensitivity, susceptibility to oxidation and potential to cause irritation in topical use, limit its direct application. The use of encapsulation processes can solve these deficiencies and improve the biological activity of EOs. This project has the following objectives: to develop standardized dispersible powders (standardized by marker compounds concentration) from lipid-based compositions loaded with essential oils of LM and RO; stabilize and modulate their release and functionality; optimize the composition and production process, and preparing a topical dosage form containing the encapsulated EOs. Lipid-based compositions loaded with essential oil will be prepared using mixtures of lipids, surfactants and co-surfactants. Optimized lipid formulations showing high encapsulation efficiency of the marker compounds will be dehydrated by freeze drying and spray drying, aiming to improve the physical-chemical properties and product stability. The product that presents good physicochemical properties will be used, in the future, as an active phytopharmaceutical ingredient in formulations for topical use with antimicrobial, antioxidant and healing activities. (AU)