Polydiacetylene Nanovesicles as Carriers of Natural Phenylpropanoids for Creating Antimicrobial Food-Contact Surfaces

The ultimate goal of this study was developing antimicrobial food-contact materials based on natural phenolic compounds using nanotechnological approaches. Among the methyl-β-cyclodextrin-encapsulated phenolics tested, curcumin showed by far the highest activity toward <i>Escherichia coli</i> with a minimum inhibitory concentration of 0.4 mM. Curcumin was enclosed in liposome-type polydiacetylene/phosholipid nanovesicles supplemented with <i>N</i>-hydroxysuccinimide and glucose. The fluorescence spectrum of the nanovesicles suggested that curcumin was located in their bilayer region. Free-suspended nanovesicles tended to bind to the bacterial surface and demonstrated bactericidal activity toward Gram-negative (<i>E. coli</i>) and vegetative cells of Gram-positive (<i>Bacillus cereus</i>) bacteria reducing their counts from 5 log CFU mL^–1 to an undetectable level within 8 h. The nanovesicles were covalently bound to silanized glass. Incubation of <i>E. coli</i> and <i>B. cereus</i> with nanovesicle-coated glass resulted in a 2.5 log reduction in their counts. After optimization this approach can be used for controlling microbial growth, cross-contamination, and biofilm formation on food-contacting surfaces