Antimicrobial Activities of Gold Nanoparticles against Major Foodborne Pathogens

作者：Zawrah M F; Abd El Moez Sherein I^*

来源：Life Science Journal-Acta Zhengzhou University Overseas Edition, 2011, 8(4): 37-44.

• Antimicrobial
• gold nanoparticles
• foodborne pathogens
• ciprofloxacin
• S. Typhimurium
• TEM

Spherical gold nanoparticles (Au) were chemically prepared and characterized by transmission electron microscope (TEM) and UV spectra. Their antimicrobial activities against major foodborne pathogens were studied. Antimicrobial activities of Au nanoparticles had been increased with their higher volume. Best antifungal activity was observed on using fluconazole coated with 40 mu l Au nanoparticles with zone of inhibition 14mm against A. niger, 13mm C. albicans and 12mm A. flavus. Minimum inhibitory concentration test (MIC) revealed synergistic effect of Au nanoparticles with ciprofloxacin when compared with ciprofloxacin alone. Best results were shown against S. Typhimurium (0.097, 0.19), B. cereus (0.19, 0.39), E. coli O157 (0.39, 0.39), P. aeruginosa and L. monocytogenes (0.39, 0.78) and finally S. aureus (0.78, 6.25) respectively. Gold nanoparticles and fluconazole coated with Au nanoparticles showed variable MIC against C. albicans, A. niger (6.25, 3.125) and A. flavus (12.5, 6.25), respectively. TEM revealed small size of gold nanoparticles (range 9-19 nm) trapped by the biofilm released by S. Typhimurium and easily attached to the surface of cell membrane which drastically disturbed its proper function like respiration and permeability. Interaction between S. Typhimurium and ciprofloxacin coated with gold nanoparticles revealed that the cell wall was loosened and separated from the membrane or disrupted with complete absence of flagella. TEM of S. Typhimurium using ciprofloxacin alone showed intact bacterial cell wall with the accumulation of antibiotic on the cell wall and partial destruction of flagella. Drugs capped gold particle act as a single group against the microorganism which was indicated by using disk diffusion method with increase zone of inhibition of Au alone, ciprofloxacin alone and Au coated ciprofloxacin from 12, 26 and 30 mm, respectively. Also, it was clarified by the decrease in MIC from 6.25, 0.19 to 0.097, respectively. Results indicated that drugs coated with nanoparticles were highly effective against tested isolates so that Au nanoparticles can minimize treatment durations and side effects of drugs. [M. F. Zawrah and Sherein I. Abd El-Moez Antimicrobial Activities of Gold Nanoparticles against Major Foodborne Pathogens] Life Science Journal. 2011; 8(4): 37-44] (ISSN: 1097-8135). http://www.lifesciencesite.com.

• 出版日期2011