الفهرس 
1. INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Nanomaterials (NMs) as a one important research area of nanotechnology have been paid great attention recently in the field of medicinal and agricultural. The great concern in the application and use of NMs is due to their unique large surface-to-volume ratio and exceptional physicochemical, electronic and mechanical properties.
The main purpose of this thesis was to the following:
1- Isolation and identification of bacteria from different sites of infections.
2- Production of silvernanoparticles using Trichoderma sp.
3- characterization the produced silvernanoparticles
4- The antibacterial effect of silvernanparticles against isolated human pathogenic bacteria and against some plant pathogenic bacteria.
5- Molecular study to show how silvernanoparticles affected on bacteria treated with silvernanoparticles when compared with untreated ones.
Isolation and identification of bacteria from different sites of infections
Twelve bacterial isolates were collected from different sites of infectious including urinary tract, respiratory tract, ear, mouth and wounds infection from patients. Specimens were collected under sterile condition they were cultured on pure media and inoculated aerobically for 24 - 48 hours. Finally after biochemical testes the bacteria were Staphylococcus aureus, Klebseilla, Echerichia coli, Pseudomonas, and Proteus. The plant pathogenic bacteria were Pectobacterium carotovorum wasabiae, Pectobacterium atrosepticum, Dickeya chrysanthemi, Pectobacterium carotovorum, Dickeya solani, Dickeya dianthicola and they obtained from the lab of Dr. Saeed Elbheiary faculty of Agriculture, Alexandria University, Egypt.
Production of silvernanoparticles using Trichoderma sp.
Addition of AgNO3 (1mM) to the filtrate caused a change in color of the reaction mixture from pale yellow to yellowish brown and this indicated to the formation of silvernanoparticles.
Characterization the produced silvernanoparticles
1- X-RAY diffraction (XRD)
(XRD) result indicated that the main composition of the nanoparticles was silver. It is also found that there are some little peaks which match with the standard XRD data of Ag2CO3.
2- Transmission Electron Microscope (TEM)
The TEM image result indicated that the silvernanoparticles size ranges from 0.025μm to 0.047μm smooth and crystal shape. Summary & Conclusion
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The antibacterial activity of silvernanparticles against isolated human pathogenic bacteria and against some plant pathogenic bacteria.
Silvernanoparticles showed high antibacterial activity against isolated human pathogenic bacteria and plant pathogenic bacteria compared to some antibiotics.
Molecular study to show how silvernanoparticles affected on bacteria treated with silvernanoparticles when compared with untreated ones.
Alignment of the DNA nucleotide sequences of the 16S rRNA genes amplified from treated and non-treated E.coli cells revealed that the similarity between the 16S DNA sequences of the treated and non-treated E. coli cells was about 55%. Consequently the similarity was 80% in case of Staphylloccocus aureus .These results commend the results obtained by PCR-RFLP, thus, we assume that the Ag nanoparticles affect the ribosomal DNA especially the 16S rRNA gene.