Optimization of solvent evaporation method in liposomal nanocarriers loaded-garlic essential oil (Allium sativum): Based on the encapsulation efficiency, antioxidant capacity, and instability

This study is aimed to optimise the preparation factors, such as sonication time (5–20 min), cholesterol to lecetin ratio (CHLR) (0.2–0.8), and essential oil content (0.1–0.3 g/100 g) in solvent evaporation method for formulation of liposomal nanocarriers containing garlic essential oil (GEO) in order to find the highest encapsulation efficiency and stability with strongest antioxidant and antimicrobial activity. The droplet size, zeta potential, encapsulation efficiency, turbidity, changes in turbidity after storage (as a measure of instability), antioxidant capacity, and antimicrobial activity were measured for all prepared samples of nanoliposome. The sonication time is recognised as the most effective factor on the droplet size, zeta potential, encapsulation efficiency, turbidity, and instability while CHLR was the most effective factor on zeta potential and instability. The content of GEO significantly affected the antioxidant and antimicrobial activity in particular against gram-negative bacteria (Escherichia coli). The results of FTIR based on the identification of functional groups confirmed the presence of GEO in the spectra of the prepared nanoliposome and also it was not observed the interaction between the components of the nanoliposome. The overall optimum conditions were determined by response surface methodology (RSM) as the predicted values of the studied factors (sonication time: 18.99 min, CHLR: 0.59 and content of GEO: 0.3 g/100 g) based on obtaining the highest stability and efficiency as well as strongest antioxidant and antimicrobial activity.