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There is an increasing interest in developing nanoparticles with diverse biologic activities. To this end, we prepared 10 to 15 nm silver nanoparticles (AgNP) from native isolates of Trichoderma atroviride. Within this study, endophytic fungi hosted four medicinal plants in Saint Katherine Protectorate, South Sinai, Egypt have been isolated by surface sterilization technique on four isolation media. Ten species, based on their frequency of occurrence, out of twenty recovered taxa were tested for their capability to synthesize extracellular AgNPs. Trichoderma atroviride hosted Chiliadenus montanus was found to be the best candidate for the production of mycogenic AgNPs among all examined species. The mycosynthesized AgNPs were compared with chemically synthesized and characterized using Ultraviolet-visible (UV-vis) spectroscopy, Raman spectroscopy, X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM) techniques. The HRTEM result showed the distribution of spherical AgNPs ranging from 10 to 15 nm. Trichoderma atroviride isolate was subjected to sequencing for confirmation of phenotypic identification. The internal transcribed spacer (ITS) 1-5.8 s-ITS2 rDNA sequences obtained were compared with those deposited in the GenBank Database and registered with accession number MH283876 in the NCBI Database. Antibacterial, anticandidal and antifungal effects of chemically and mycosynthesized AgNPs were examined at various concentrations in vitro against six pathogenic bacteria and 4 pathogenic fungi by agar well diffusion technique. Standard antibiotics; Gentamicin, Amoxicillin, Clotrimazole, and Nystatin at 5 μg/disk were taken as positive controls, while 5% DMSO was used as the negative control. Our data revealed that the application of mycogenic AgNPs at a concentration of 100 ppm resulted in maximum inhibition of pathogenic bacteria and fungi. These data suggest that AgNPs from native isolates of Trichoderma atroviride (MH283876) offer a source of rapid synthesis of eco-friendly, economical biomaterials that show antimicrobial activities.

Zinc ferrite @ titanium dioxide (ZnFe2O4@TiO2) composite nanofibers were elaborated by combining the two different techniques: electrospinning and plasma enhanced chemical vapour deposition (PECVD). The nanofibers compositions were controlled using different ratio of zinc to iron. Their structural, morphological, and optical properties were analysed by scanning electron microscopy (SEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), BET surface area, Raman spectroscopy and UV-Visible spectrophotometry. The photocatalytic activity has been investigated by the degradation of methylene blue (MB) under visible light. The results indicate that the combination of spinel structure with titanium dioxide improves the photodegradation up to 98%. The deposition of TiO2 via PECVD on zinc ferrite enhances the absorption of TiO2 into the visible region and increases the electron-hole separation. In addition, the improved surface area can promote adsorption, desorption and diffusion of reactants and products, which is favourable to obtain a high photocatalytic activity.

h i g h l i g h t sSelf-supported CNF-Ni/NiO-Pd electrodes were fabricated. Electrospinning with atomic layer deposition were used for the electrode fabrication. CNF-Ni/NiO-Pd electrodes were used for HER and OER reactions under acidic and basic conditions. CNF-Ni/NiO-Pd electrodes have shown high HER and OER activity compared to Pt and IrO 2 catalysts. Synergistic effect between the graphitic nanosheets, Ni/NiO and Pd NPs at the nanointerfaces has been highlighted.

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