الفهرس 
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Abstract
In the present study, 54 endophytic fungi were isolated from different plant species. Morphological examination of the isolated fungal cultures revealed that they are belonging to seven genera. Among these isolated endophytic fungi screened for the ability to reduce the five types of metal, one isolate named ORG-1 and recovered from the leaves of Origanum majorana had the ability to reduce the five types of metal. Morphological and molecular characterization confirmed that the ORG-1 strain had a high identity with Aspergillus terreus AUMC14389. characterizations of the synthesized NPs were confirmed by several techniques. In vitro studies of antibacterial, antifungal and antioxidant activities of the synthesized NPs were evaluated. The potentiality of fungal strain for further improvement of NPs productions was applied through exposure to gamma radiation. Moreover, the in vivo studies on the application of the synthesized NPs as fungicide and nanoferitilizer have been demonstrated. The main experimental results can be summarized as follows:
1- A total of 54 endophytic fungal isolates were isolated on PDA plates from different plant species grown at several campuses and cultivated areas and chosen as sources for the isolation of NPs producing endophytic fungi revealed that they belong to seven genera.
2- In the screening study of the potentiality of the isolated fungal endophytic for NPs production, moreover, an isolate named ORG-1 and recovered from the leaves of Origanum majorana was able to reduce all the five types of metal salts.
3- Based on macroscopic, microscopic characteristics, and phylogenetic characteristic analysis, the respective isolate was identified as Aspergillus terreus AUMC14389.
4- characterization of the synthesized NPs was performed with several techniques. In the recorded UV–Vis spectra of the synthesized NPs, the recorded absorption peaks were at 230 nm for Co3O4NPs, 256 nm for CuONPs, 285 nm for Fe3O4NPs, 330 nm for NiONPs and 370 nm for ZnONPs.
5- The planes in the XRD pattern confirm the crystal structures of synthesized NPs.
6- The DLS analysis showed that the mean sizes of the synthesized NPs. The recorded polydispersity index (PDI) and Zeta potential values of the synthesized NPs indicated that the synthesized NPs have high stability.
7- TEM micrographs of Co3O4NPs, CuONPs, Fe3O4NPs and NiONPs revealed the spherical shape of the synthesized NPs. Meanwhile, the TEM micrograph of ZnONPs showed that the synthesized NPs were almost spherical in shape with irregular margins.
8- The FTIR-spectroscopic analysis was indicated the formation of new bands in the spectrum of the synthesized NPs, which may be due to conjugation of these NPs. However, there are no bands corresponding to any of these bands in the spectrum of the cell-free filtrate.
9- The antioxidant behavior of the synthesized NPs indicated that all the five NPs types had promising antioxidant activity at different concentrations.
10- The antibacterial activity of the synthesized NPs revealed that the recorded MIC for Co3O4NPs were 100μg mL−1, CuONPs were 100 μg mL−1, except P. aeruginosa were 250 μg mL−1, Fe3O4NPs against (E.coli and S. aureus) were 100 μg mL−1 and 250 μg mL−1 for (P. aeruginosa and K. pneumonia), NiONPs were 500 μg mL−1 except against E.coli was 250μg mL−1 and ZnONPs against E. coli were 100 μg mL−1, S. aureus were 250 μg mL−1 and (P. aeruginosa, K. pneumonia) were 500 μg mL−1.
11- The antifungal activities of the synthesized NPs showed that the MIC value of Co3O4NPs were 100 μg mL−1, CuONPs were 100 μg mL−1, Fe3O4NPs against (A. brasiliensis and C. albicans) were 100 μg mL−1 and 250 μg mL−1 for (F. oxysporum and A. alternata), NiONPs were 250 μg mL−1 and ZnONPs against (A. brasiliensis and C. albicans) were 100 μg mL−1 and (F. oxysporum and A. alternata) were 500 μg mL−1.
12- Six types of broth media were screened for biosynthesis of NPs by A. terreus, the obtained results revealed that the strain showed the highest NPs production using SAB broth medium.
13- Different physical factors showed that maximum concentrations of NPs were obtained by strain after 9 days, at 30ºC, pH 6, 50 mL production medium and using 2 mL inoculum of A. terreus from 7 day old culture.
14- RSM program was used to study the optimum levels of physical conditions controlling the biosynthesis of NPs by the cell-free filtrate of the strain. After optimization, the final yields of the respective NPs reached 338.51 for Co3O4NPs, 335.89 for CuONPs, 230.55 for Fe3O4NPs, 765.45 for NiONPs, 862.55 for ZnONPs mg L-1.
15- Under the optimum conditions and after gamma irradiation, at the best dose (1 KGy), the final yields of the respective NPs reached 70, 76, 168, 482, 53.95 fold of their respective initial titers before optimization) Co3O4NPs, CuONPs, Fe3O4NPs, NiONPs and ZnONPs, respectively).
16- Controlling of Fusarium wilt disease in P. vulgaris L. by five NPs. It was found that the applied NPs had different and varied impacts on the studied parameters for both the therapeutic and protective experiments. It could be easily deduced that the impact of the studied NPs was much more promising in the protective experiment rather than therapeutic one.
17- It is obvious the CuONPs was the most effective treatment to decline the negative effect of Fusarium wilt disease on the tested plant followed by ZnONPs, Co3O4NPs, Fe3O4NPs and NiONPs, respectively. Results also revealed that applied NPs had much more positive impact on disease severity (%) rather than the disease incidence (%) or disease control (%).
18- All the applied NPs raised the values of the vegetative growth parameters as compared with the infected plants. The most superior NPs to maintain plant growth was CuONPs followed by ZnONPs, Co3O4NPs, Fe3O4NPs and NiONPs, respectively.
19- Scanning electron microscopy used to elucidate the mechanism of CuONPs as superior fungicide. Concerning F. oxysporum showing lack of reproductive structures and distorted mycelia and intense dehydration. Treated mycelia demonstrated completely damaged or dead cells.
20- In addition to the role of the NPs as a fungicide for controlling pathogens attacked growing plant, their role as a promoting agent was also considered. The data revealed that the promotion effect of the all applied NPs on germination percent and vegetative growth of P. vulgaris.
21- Data explained that the impact of the applied NPs on pigment content of red bean. All applied NPs had the capacity to increase significantly leaves pigment content. The most superior NPs to promote pigment synthesis were found to be CuONPs followed by ZnONPs, Co3O4NPs, NiONPs and Fe3O4NPs.
In conclusion, the endophytic fungal strain A. terreus (AUM 14389) was successfully able to synthesized five types of NPs (Co3O4NPs, CuONPs, Fe3O4NPs, NiONPs and ZnONPs). These NPs have a potent antimicrobial and antioxidant abilities. Optimization of growth conditions, physical conditions of the biosynthesis of NPs by the cell-free filtrate of the strain and gamma irradiation profoundly increase the yield of NPs. Also these NPs were able to control Fusarium wilt disease and enhance growth of red bean under greenhouse conditions. So, these NPs can be promising as safe fungicide agents and nano-fertilizers.
Recommendation:
This study recommends using the fungal strain A. terreus (AUM14389) as promising and attractive sources to complete an economic reduction process for the production of the five nanoparticles. This study also recommends the importance of using radiation to improve the production of NPs by this fungal strain. It can also be used as a fungicide and plant stimulating.