Physicochemical Characteristics of Nanoliposome Garlic (Allium sativum L.) Essential Oil and Its Antibacterial Effect on Escherichia coli O157:H7

Background: Escherichia coli O157:H7 is a Gram-negative and facultative anaerobic food-borne bacterial pathogen. The major purpose of this study was to evaluate physicochemical characteristics of nanoliposome garlic Essential Oil (EO) and its antibacterial effect on E. coli O157:H7. Methods: Nanoliposome garlic EO was prepared by ethanol injection method and its physicochemical properties were evaluated. After inoculation of E. coli O157:H7 to experimental groups, minimum inhibitory concentration and minimum bactericidal concentration were assessed. Data were analyzed using SPSS software (version 16.0). Results: The average particle sizes of prepared nanoliposomes were 131.73±14.31 nm with a polydispersity index of 0.212±0.013. The percentage of liposome permeability after 5, 10, 30, and 50 days were 0.46%, 2.47%, 5.63%, as well as 7.29%, respectively, revealing significant difference (p < 0.05) among various intervals. Also, the minimum inhibitory concentration as well as minimum bactericidal concentration values of the nanoliposome encapsulated garlic EO against E. coli O157:H7 were 0.02% and 0.03%, respectively, and for non-encapsulated EO were 0.03% and 0.04%, respectively. Conclusion: Nanoliposome encapsulated garlic EO showed enhancing antimicrobial activity against E. coli O157:H7 in comparison with the non-encapsulated one.