Preparation, characterization and antifungal activities of ε-polylysine-decorated nanoliposomes loaded with cinnamaldehyde

Development of materials with green and efficient for restraining the growth of the harmful microorganisms is vital for food safety. Herein, we constructed nanoliposomes with cinnamaldehyde (CIN), an active component of natural cinnamon essential oil, for the long-term inhibition of microbes in food spoilage. In this strategy, cinnamaldehyde nanoliposomes (CIN-NLs) were prepared by the method of thin film dispersion, and then decorated with ε-polylysine (ε-PL) to obtain ε-polylysine/cinnamaldehyde nanoliposomes (ε-PL/CIN-NLs). Results identified that CIN-NLs and ε-PL/CIN-NLs were in spherical and nanoscale, and the nanoliposomes had larger particle size distribution (122.5 ± 3.51–680.4 ± 7.40 nm) and higher encapsulation efficiency (19.4 ± 0.3–30.4 ± 0.2%) after ε-PL (2 mg/mL) decoration. When the CIN concentration was 4 mg/mL, the highest encapsulation efficiency was acquired as 30.4 ± 0.2% by ε-PL/CIN-NLs. CIN-NLs and ε-PL/CIN-NLs showed great activity on inhibiting the growth of Aspergillus flavus and Penicillium citreo-viride , and the inhibition zone diameter of ε-PL/CIN-NLs (26 ± 1.1 mm and 45 ± 1.7 mm, respectively) was significantly larger than that of CIN-NLs (20 ± 1.5 mm and 35 ± 2.1 mm, respectively) in final growth of two fungi. The studies indicated that that ε-PL decoration effectively improved the long-term antifungal activity characteristics of CIN nanoliposomes. Findings from current study can provide a new method to prevent food spoilage and direct future development of green antifungal packing for use in food preservation. Graphical abstract The schematic representation of ε-PL/CIN-NLs and the colony growth images of Aspergillus niger and Penicillium citreo-viride.