Antibacterial Effect of Silver Nanoparticles Against Four Foodborne Pathogens

Abstract

Background:There is increased demand for improved disinfection methods due to microorganisms resistant to multiple antimicrobial agents. Numerous types of disinfectants are available with different properties; but the proper disinfectant must be carefully selected for any specific application to obtain the desired antimicrobial effect.Objectives:Antimicrobial effect of a commercial nanosilver product, NanoCid® L2000, against some foodborne pathogens was evaluated.Materials and Methods:Minimum inhibitory concentrations (MIC) were determined by monitoring the growth of bacteria at 600 nm, after 24 hours incubation at 35°C. Minimum bactericidal concentrations (MBC) were determined based on 3 log decrease in the viable population of the pathogens after incubation of nutrient agar plates at 35°C for 24 hours. The required exposure time for 3 log reduction in the viable population of the tested pathogens was determined as the minimum exposure time for efficient bactericidal activity.Results:The MIC values of Ag NPs against tested pathogens were in the range of 3.12-6.25 µg/mL. While Listeria monocytogenes showed the MIC value of 6.25 µg/mL, Escherichia coli O157:H7, Salmonella typhimurium and Vibrio parahaemolyticus all showed the MIC values of 3.12 µg/mL. However, all the pathogens showed the same MBC value of 6.25 µg/mL. To obtain an efficient bactericidal activity against E. coli O157:H7 and S. typhimurium, the exposure time should be at least ca. 6 hours., while this time was ca. 5 hours for V. parahaemolyticus and ca. 7 hours for L. monocytogenes.Conclusions:Silver nanoparticles showed great antibacterial effectiveness on four important foodborne pathogens. Therefore, Ag NPs could be a good alternative for cleaning and disinfection of equipment and surfaces in food-related environments.

Silver and gold nanoparticles synthesized from Streptomyces sp. isolated from acid forest soil with special reference to its antibacterial activity against pathogens

“…Moreover, silver ions released from NPs interact strongly with thiol groups in enzymes and phosphoruscontaining bases. Interaction of AgNPs with DNA may prevent bacterial cell division and DNA replication leading to cell death [4,[68][69][70].…”

Antibacterial Activity of Silver Nanoparticles Synthesized by Using Extracts of Hedera helix

“…In 2014 Zarei et al tested antibacterial effect of silver nanoparticles (synthesis by chemical methods) against four foodborne pathogens (Listeria monocytogenes, Escherichia coli, Salmonella typhimurium and Vibrio parahaemolyticus) that silver nanoparticles showed great antibacterial effectiveness on four important foodborne pathogens [18].…”

Environmental Aspects of Using Nanomaterials

“…Metallic nanoparticles are also used in the agriculture, veterinary medicine, food industry and cosmetology [13]. Table 1 presents the list of microorganisms to which the biocidal activity of nanosilver has been confirmed [14][15][16][17][18][19][20][21][22][23]. Silver nanoparticles are effective factor for destroying a wide range of Gram-negative and Gram-positive bacteria.…”

“…Acinetobacter [14] HIV-1 [21] Aspergillus [22] Escherichia [15] Influenza virus [21] Candida [23] Pseudomonas [14] Saccharomyces [24] Salmonella [16] Bacillus [16] Enterococcus [17] Listeria [18] Staphylococcus [19] Streptococcus [20] The European Commission on Nanomaterials claims that there is a huge need of monitoring the quality and quantity of nanoparticles that are introduced to consumer products. A regulation was issued that all types of nanoparticles that are used in cosmetic products as UV-filters, colourants and preservatives must be registered [28].…”