Anchovy Antibacterial Peptide Liposome Preparation and Antibiofilm Activity against Listeria monocytogenes

Abstract:

Anchovy antibacterial peptide (AAP) liposomes were prepared via thin film evaporation technique in this work. The average particle diameter, morphological structure, encapsulation efficiency, and stability of the prepared liposomes were analyzed, and the antibacterial and antibiofilm activities against Listeria monocytogenes were also evaluated. The results showed that the average particle size of AAP liposomes was 131.65±1.63 nm, the encapsulation efficiency was 69.75%, and the effective load of AAP was 4.17%. The liposomes were nearly spherical with an annular lamellar distribution. The storage stability of the liposomes under 4 ℃ was higher than that of those under 25 ℃. AAP and its liposomes could inhibit the growth of L. monocytogenes, but free AAP and AAP liposomes affected the growth curves in a slightly different way, because of the controlled release effect of the liposome. The antibiofilm activity of the liposomes was higher than that of free AAP. Crystal violet and silver staining experiments showed that the AAP lipid could inhibit L. monocytogenes biofilm formation. Scanning electron microscope and confocal laser scanning microscopy showed that AAP liposomes could cause the collapse of bacterial cell structure, and result in cell membrane damage and expulsion of intracellular material, further inhibiting biofilm formation.