الفهرس 
1. INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The current study dealt with the green biosynthesis of copper nanoparticles (CuNPs) utilizing local bacteria isolated form the Egyptian lands. Out of 160 bacterial isolates of various plant rhizospheres and seawater samples, only 16 copper-resistant isolates were able to synthesize CuNPs. Isolate I 108 with the pioneer CuNPs profile of particle size about 87.1 nm with UV absorbance at 580 nm of 0.54 and particles concentration of 12.21 ppm. The pioneer isolate was identified genotypically and phenotypically to be 98% similar with Pseudomonas silesiensis strain A3. Optimization of CuNPs biosynthesis with P. silesinsis strain A3 cell-free supernatant was carried out by 2 optimization steps. The 1st step was including OVAT investigation for the best agro-industrial waste and by-product as carbon source and various nitrogen sources, it was found that 2% blackstrap sugarcane molasses (BSM) and 1.5% tryptone were the promising nutrition sources enhancing the cell-free extract (extracellular biosynthesis) as incubated at 30°C for 24 h at 120 rpm with CuNPs profile; size of 44.8 nm at a concentration of 34.55 ppm, maximum surface plasmon peak (SPR) of 1.17 and 9.33 U/ml of Cu-reductase. Followed by 2nd optimization complementary approaches using RSM methodology including Taguchi (TD) and Box-Behnken (BBD) design investigating the P. silesiensis strain A3 Cu-reductase followed by CuNPs biosynthesis maximization. Among 7 factors studied for P. silesiensis strain A3 Cu-reductase production, only 3 factors are significant namely BSM, tryptone and temperature at 2.75%, 1.75% and 37.5°C, respectively as CuNPs parameters enhanced as the SPR absorbance, Cu-reductase activity and CuNPs concentration were 2.01, 10.84 U/ml and 55.32 ppm respectively. In order to enhance the biosynthesis of CuNPs, Five factors out of seven gave significant effect (temperature, reaction time, cell-filtrate ratio, pH, and concentration of copper sulfate solution), which constraint the optimum level for each factor to be as follow; temperature at 40°C, cell-free extract ratio of 1:3 and copper sulfate concentration of 3 mM, pH 7, and 48 h for reaction time which scored 3.2, 24.91 U/ml and 93.5 ppm for SPR, Cu-reductase activity and concentration of CuNPs, respectively. The characterization of CuNPs by HR-TEM, DLS, XRD, and FTIR showed 30 nm spherical, monodispersed, crystalline and protein coated with zeta potential of -30 mv particles. Owing to the fabulous profile, the particles have excellent stability for 10 months. The cytotoxicity assessment using Wi38 human lung normal cell lines ensured CuNPs biocompatibility with antimicrobial and antitumor applications, till the IC50 dose was 1057.0 μg/ml. The antimicrobial investigation revealed that the most susceptible microorganisms were Staphylococcus aureus ATCC 5638 and Aspergillus flavus ATCC 9643 with 50 mm and 47 mm inhibition zone (IZD), respectively, in contrary Pseudomonas aeruginosa ATCC 27853, and Fusarium oxysporum ATCC 62705 were the lowest susceptible with minimum IZD by 18 and 28 mm, respectively. The CuNPs were found to have a broad spectrum activity against all the tested microbial pathogens. Antitumor investigation using A549 human cancer lung cell lines, showed IC50 dose of 137.5 μg/ml which indicated high safety level for CuNPs, so it could be noticed that the produced CuNPs could be applied as antitumor therapeutics and antimicrobial with more further studies.