Development and characterization of phosphatidylcholine nanovesicles, containing garlic extract, with antilisterial activity in milk

- Garlic extract was encapsulated into phosphatidylcholine liposomes.
- Nanoliposomes showed a mean diameter of 174.6 nm and zeta potential of −16.2 mV.
- Nanoliposomes containing garlic extract inhibited diverse strains of Listeria spp. in milk.
- Nanotechnology may be a useful strategy to delivery natural antimicrobials in food.

Phospholipid nanovesicles were developed to improve the stability of garlic (Allium sativum L.) extract. Electron microscopy of liposomes revealed nanometric and spherical-shaped vesicles with a mean particle size of 174.6 ± 17.3 nm and polydispersity index of 0.26 ± 0.02. The entrapment efficiency was 47.5 ± 7.3% and the nanoliposomes had a zeta potential of −16.2 ± 5.5 mV. The antimicrobial activity of free and encapsulated garlic extract was evaluated against different strains of Listeria spp. in milk at 37 °C for 24 h. For free and encapsulated garlic extracts at 5% concentration, a decrease of 4 log cycles in viable cell counts was observed at 10 h, against four of the five strains of Listeria spp. tested. The results indicate that liposomes constitute a suitable system for encapsulation of unstable garlic active compounds and the encapsulation of garlic extract proves to be a promising technology for multiple applications, including antimicrobial agents.