Abstract

Background/objectives: Foodborne diseases remain a significant global public health concern, requiring innovative and effective antimicrobial strategies to control food pathogens. Encapsulation of natural antimicrobials have attracted increasing interest. In this study, liposomes encapsulating pink pepper essential oil (PPEO), nisin, or their combination were developed, aiming to potentiate antimicrobial performance against foodborne pathogens. Methods: Phosphatidylcholine liposomes were prepared by the thin-film method and characterized by DLS and FTIR. The antimicrobial activity of nisin, PPEO, and liposomes was investigated by the agar diffusion method against foodborne pathogens like Staphylococcus aureus, Listeria monocytogenes, and Salmonella Typhimurium. Results: The liposomes exhibited nanometric size ranging from 91 to 107 nm, low polydispersity, and zeta potential between −3.73 and −7.39 mV, indicating well-defined vesicles with negative surface charges. Encapsulation enhanced antimicrobial efficacy, with nisin–PPEO liposomes stored for 21 days under refrigeration showing a sustained inhibition of L. monocytogenes, outperforming liposomes containing nisin alone. The combined antimicrobials also inhibited Gram-positive bacteria in milk agar, used as a simulated food system. Additionally, the antioxidant activity of PPEO was preserved upon encapsulation, especially under refrigeration, reinforcing the protective role of the liposomes. Conclusions: The co-encapsulation approach strengthened the stability and bioactivity of natural antimicrobials, highlighting liposomal delivery as a promising strategy to control foodborne bacteria.

IPC Classification

Keywords