Characterization and Antilisterial Effect of Phosphatidylcholine Nanovesicles Containing the Antimicrobial Peptide Pediocin

Abstract

Encapsulation may provide increased stability and antimicrobial efficiency to bacteriocins. In this work, the antilisterial peptide pediocin was encapsulated in nanovesicles prepared from partially purified soybean phosphatidylcholine. The maintenance of antimicrobial activity and properties of free and encapsulated pediocin was observed during 13 days at 4 °C, and after this period, the encapsulated pediocin retained 50 % its initial activity. The maintenance of the bioactive properties of free and encapsulated pediocin was observed against different species of Listeria, inhibiting Listeria monocytogenes, Listeria innocua and Listeria ivanovii. The size of vesicles containing pediocin was determined by dynamic light scattering as an average of 190 nm, with little change throughout the observation period. Polydispersity index values were around 0.201 and are considered satisfactory, indicating an adequate size distribution of liposomes. The efficiency of encapsulation was 80 %. Considering these results, the protocol used was appropriate for the encapsulation of this bacteriocin. Results demonstrate the production of stable nanoparticulate material. The maintenance of the properties of pediocin encapsulated in liposomes is fundamental to prospect the stability in different conditions of the food matrix.

Nanotechnology: A Valuable Strategy to Improve Bacteriocin Formulations

“…These findings suggest that the stability of bacteriocins against unfavorable environmental conditions can be improved by nanoliposomal formulations, which still remains to be proved by assessing their AMA (Taylor et al, 2007 ). A similar study was reported by de Mello et al ( 2013 ), in which pediocin AcH had been successfully loaded with high (80%) entrapment efficiency, stability, and antimicrobial activity, for at least 13 days, when incorporated into phosphatidylcholine nanovesicles (de Mello et al, 2013 ). However, it must be stated that while the liposome-encapsulated pediocin has been shown to maintain its AMA for a longer period, this activity was lower than that of the free pediocin, which requires further investigations to overcome this issue (de Mello et al, 2013 ).…”

“… Schematic representation showing some of the nanotechnological approaches used in bacteriocin formulations with their associated characters . 35, da Silva Malheiros et al, 2012a ; 41, da Silva Malheiros et al, 2012b ; 46, de Mello et al, 2013 ; 69, Zohri et al, 2010 ; 70, Zohri et al, 2013 ;71, Bernela et al, 2014 ; 72, Chopra et al, 2014 ; 33, Mossallam et al, 2014 ; 80, Thirumurugan et al, 2013 ; 87, Sharma et al, 2012 ; 94, Heunis et al, 2013 ; 95, Heunis et al, 2011 ; 100, Ahire and Dicks, 2015 ; 101, Ahire et al, 2015 . …”

Food Safety through Natural Antimicrobials

“…Gram-positive bacteria are inhibited by most bacteriocins. Gram-negative bacteria can be increasingly sensitive to bacteriocins after the use of chelating agents or hydrostatic pressure [205,206]; these techniques can also be synergic enhancing the action of bacteriocins against Gram-positive bacteria [189,207], or even with the use of nanoparticles [208,209] or nanovesicles [210].…”

“…Human epidermal keratinocytes studies showed that these nanoparticles were non-toxic at the concentrations used to inhibit microbial growth. Nisin nanoparticles have been tested against L. monocytogenes and S. aureus with good results [302][303][304], as well as bacteriocin nanovesicles [210] or nanoparticles [208,209] against different pathogens. Zou et al [302] evaluated the prolonged antimicrobial stability of liposome nanoparticles loaded with nisin against L. monocytogenes and S. aureus.…”

“…Three more derivatives were developed and tested against E. coli, Cronobacter sakazakii, and S. enterica serovar Typhimurium showing enhanced antimicrobial activity. Encapsulation provides stability to bacteriocins; thus, de Mello et al [210] encapsulated the peptide pediocin in nanovesicles of soybean phosphatidylcholine. The nanovesicles maintained 50% of the pediocin antimicrobial activity for 13 d at 4 • C against Listeria monocytogenes, L. innocua, and L. ivanovii.…”