الفهرس 
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Abstract
Macrophomina phaseolina (Tassi) and Sclerotium rolfsii Sacc. having a wide host range about 500 plant species for each. These isolates were capable to produce the zinc hydroxide nanoparticles (Zn(OH)2-Nps) as the first natural source and synthesized by simple and low cost method.
The synthesized nanoparticles were characterized by UV-Vis, transmission electron microscope (TEM), Fourier transform infrared (FTIR) and X-ray diffraction (XRD). The antimicrobial activity of Zn(OH)2-Nps were investigated by agar disc diffusion method to determine the minimal inhibitory concentration (MIC). The nanoparticles exhibited potent antifungal activity against air-soil borne pathogens, Exserohilum rostratum and Fusarium solani. The biosynthesized Zn(OH)2-Nps inhibited the growth of microbial strains at all the tested treatments. Additionally, the recorded inhibition zones were increased proportionally with increasing the concentration of the Zn(OH)2-NPs.
Talaromyces stipitatus was used to increase the effectiveness of silver and silver chloride nanoparticles (Ag/AgCl-NPs). As the Ag+ ions change dynamically, the color of the filter changed from green to brown. Transmission electron microscopy revealed that T. stipitatus formed homogeneous spherical Ag/AgCl-NPs with recorded sizes from 25 to 30 nm (TEM). X-ray powder diffraction was used to evaluate the fabrication of pure cubic crystals of Ag/AgCl-NPs and AgCl-NPs (XRD). Fourier transform infrared spectroscopy was used to investigate the reduction of Ag+ ions and thus the production and stability of Ag/AgCl-NPs by T. stipitatus (FTIR). The polysaccharide-conjugated proteins or proteins from the fungal filter were shown to stabilize the bioreducing nanoparticles. The biosynthesis of Ag/AgCl-Nps using Talaromyces stapitatus is an efficient technique for nanoparticles production, and would be appropriate for large-scale production.
Keywords: Endophytes, biosynthesis. Talaromyces stipitatus, sweet pepper, Silver, nanoparticles characterization. Macrophomina phaseolina, Sclerotium rolfsii, Zinc hydroxide.