Investigating the effect of biosynthesized silver nanoparticles as antibiofilm on bacterial clinical isolates.
Microb Pathog
; 116: 200-208, 2018 Mar.
Article
en En
| MEDLINE
| ID: mdl-29414608
ABSTRACT
Silver nanoparticles showed enhanced biofilm inhibitory activity of clinical pathogens. Eleven isolates (45.8%) of E. coli bacteria were obtained from 24 wound specimens. Silver nanoparticles biosynthesized by E. coli culture supernatant with exhibition dark brown color after 24â¯hr of incubation. Scanning electron microscopy showed that Ag-NPs spherical particles and its size were (14.2-67.8) nm and its average was 33.6â¯nm. X-ray diffraction shows one high peak at 2ø (32.5°) compared with standard data. Fourier transform infrared spectroscopy analysis of Ag-NPs exposed the strong band at 1367.53 corresponds to OH-bend which influences the synthesis and stability of Ag-NPs, whereas the stretch for Ag-NPs found at 518.58â¯cm-1. The antibacterial effect of Ag-Nps against E. coli, P. aeruginosa, K. pneumoniae and S. aureus showed the inhibition zone of 10, 11, 13, and 10â¯mm, respectively. Strong biofilm formed by isolates of E. coli exhibited as black colonies on Congo red agar, while pink colonies on it with Ag-Nps, indicating a loss of biofilm formation ability in all tested bacterial isolates. Antibiofilm of 10â¯mM Ag-Nps by Microtiter plate exhibited lower biofilm inhibition against S. aureus reached to 22.2%, while 36.2% against E. coli, 30.4% for K. pneumonae, and P. aeruginosa 94.7%. Analysis of biofilm components after exposure to Ag-NPs by FT-IR reveals a low level of proteins, polysaccharides, lipids and nucleic acids compared with controls, then glucose formation measured and exhibited reduction of absorbance (0.146â¯nm) after treatment with Ag-Nps compared with control (0.347â¯nm), while the percentage of protein decreased completely (0%) compared with control (0.25%). The combined effect of Ag-NPs with antibiotics enhanced the antibiofilm activity which tested under inverted microscope (40X).
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Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Plata
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Biopelículas
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Escherichia coli
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Nanopartículas
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Bacterias Gramnegativas
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Bacterias Grampositivas
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Antibacterianos
Límite:
Humans
Idioma:
En
Año:
2018
Tipo del documento:
Article