Antibacterial and anti-biofilm properties of cinnamaldehyde-loaded nanoliposomes against Listeria monocytogenes and Salmonella enteritidis adhered to stainless steel

Abstract

This study aimed to investigate the effect of cinnamaldehyde (CIN)-loaded nanoliposomes (CIN-NLs) on pre-established biofilms of L. monocytogenes and S. enteritidis. The MIC and MBC values of CIN were 1.25 and 5 μg mL−1 against L. monocytogenes, respectively; while for S. enteritidis, MIC of 0.625 and MBC of 2.5 μg mL−1 were obtained. The CIN-NLs displayed particle size in the range of 130.5–414.2 nm, polydispersity index (PDI) values in the range of 0.28–0.59, and ζ-potential values above −30 mV. The encapsulation efficiency of CIN in NLs ranged from 7.47% to 27.42%. Transmission electron microscopy (TEM) displayed smooth spherical particles, and Fourier transform infrared spectroscopy (FT-IR) results showed the successful loading of the CIN into NLs. The anti-biofilm assays confirmed that the CIN-NLs more efficiently prevented the formation of biofilm and extends the action time than that of free CIN. Therefore, NLs could improve the stability and long-lasting antibacterial effect of CIN.