Zarei Mehdi, Jamnejad Amirhesam, Khajehali Elahe
Department of Food Hygiene, Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, IR Iran.
Department of Food Hygiene, Faculty of Veterinary Medicine, Shiraz University of Medical Sciences, Shiraz, IR Iran.
Jundishapur J Microbiol. 2014 Jan;7(1):e8720. doi: 10.5812/jjm.8720. Epub 2014 Jan 1.
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.
Antimicrobial effect of a commercial nanosilver product, NanoCid® L2000, against some foodborne pathogens was evaluated.
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.
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.
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.
由于微生物对多种抗菌剂产生耐药性，对改进消毒方法的需求日益增加。有多种具有不同特性的消毒剂可供选择；但对于任何特定应用，必须仔细选择合适的消毒剂以获得所需的抗菌效果。
评估一种商业纳米银产品NanoCid® L2000对某些食源性病原体的抗菌效果。
通过在35°C孵育24小时后，于600 nm处监测细菌生长来确定最低抑菌浓度（MIC）。基于在35°C孵育营养琼脂平板24小时后病原体活菌数量减少3个对数来确定最低杀菌浓度（MBC）。将测试病原体活菌数量减少3个对数所需的暴露时间确定为有效杀菌活性的最短暴露时间。
银纳米颗粒对测试病原体的MIC值在3.12 - 6.25 µg/mL范围内。单核细胞增生李斯特菌的MIC值为6.25 µg/mL，而大肠杆菌O157:H7、鼠伤寒沙门氏菌和副溶血性弧菌的MIC值均为3.12 µg/mL。然而，所有病原体的MBC值均为6.25 µg/mL。要对大肠杆菌O157:H7和鼠伤寒沙门氏菌获得有效的杀菌活性，暴露时间至少应为约6小时，而对副溶血性弧菌此时间约为5小时，对单核细胞增生李斯特菌约为7小时。
银纳米颗粒对四种重要的食源性病原体显示出强大的抗菌效果。因此，银纳米颗粒可作为食品相关环境中设备和表面清洁与消毒的良好替代品。
