In recent years, nanotechnology has become one of the emerging fields of nanoparticle synthesis using biological processes. The use of mushroom extract is one of the most important methods for biological synthesis due to the presence of abundant biologically active compounds. In this study, Zinc Oxide nanoparticles (ZnO NPs) were synthesized using Daedalea sp. mushroom extract. The nanoparticles had an average size of 14.58 nm and irregular morphology, which shows its prominent character. Various analytical techniques including FTIR, X-ray diffraction, EDX, and UV-Vis spectrum showed a broad absorption between 350 and 380 nm, which indicates the synthesis of ZnO NPs. The characterized NPs were exploited for a wide range of biomedical applications including biocompatibility, antifungal, antileishmanial, and antibacterial studies. The ZnO nanoparticles showed a strong antibacterial effect against gram-positive (Klesbsilla pneumonia and Staphylococcus aureus) and gram-negative (Eschericia coli and Pseudomonas aeruginosa) bacteria. Furthermore, the ZnO nanoparticles also showed a high antifungal effect against Aspergillus niger fungus.

Tomatoes (Solanum tuberosum L.) are considered one of the most effective and nutritious foods in the human diet. Moreover, the fruit of a tomato is rich in phytochemical compounds such as carotenoids, vitamins, and phenolics which are beneficial to human health. The objective of this present research was to investigate the impact of biogenic Ag-containing nanoparticles on seed germination rate and germination speed index, the development of the stem and root system, and physio-biochemical parameters. Ag-containing nanoparticles were synthesized biologically using a silver nitrate solution and aqueous seed extract of Juniperus procera, which acted as a capping and reducing agent. The impact of different concentrations (0.0, 2.5, 5, 10, and 25 mg/L) of Ag-containing NPs on seed germination rate, biomass accumulation, phenolic compounds, total protein, enzymes activity, and total soluble sugar of tomatoes (Solanum tuberosum L.) in vitro has been tested. The obtained result demonstrated that Ag-containing nanoparticles have a significant impact on tomato seed germination rate, germination speed index, and the development of stem and root systems. As well as photosynthetic pigments, total protein, enzymes activity, phenolic compounds, and total soluble sugar. We concluded that Ag-containing NPs can be a promising nano-fertilizer for improving crop growth and production.

As the direct effects of climate change on the hydrological regime, Saudi Arabia has constructed more than 522 dams of various capacities as part of economic and environmental development. The study aims to assess the impact of dams on plant diversity, vegetation structure and soil in Saudi Arabia. Thirty-five stands were selected from the dams of different sizes of Saudi Arabia. Vegetation samples were established before (upstream) and after (downstream) the dam, and at the undammed (unaffected by the dam) to compare species diversity in the dam sites and undammed sites and to document the potential effects of dams on vegetation structure. A total of 151 plant species belonging to 36 families have been recorded. The vegetation associations are essentially shrubby with widespread annuals. Six novel associations were identified with the application of TWINSPAN, DCA, and CCA programs. They were named after the characteristic species as follows: VG I: Acacia gerrardii-Caralluma retrospiciens; VGII: Acacia tortilis-Maerua oblongifolia; VGIII: Lycium shawii-Farsetia aegyptiaca; VG IV: Farsetia stylosa-Cornulaca monocantha; VG V: Suaeda aegyptiaca-Salsola imbricata-Prosopis farcta and VGVI: Xanthium strumarium-Ochradenus baccatus. These plant communities are evaluated and discussed according to their floristic structure, vegetation diversity and edaphic variables. The riparian or streamside zones upstream and downstream that are periodically flooded contain highly diverse plant communities that are structured by flooding, which creates disturbance and acts as a dispersal mechanism for plants than undammed sites.

Curcuma longa L. is a famous spice cultivated in many countries with significant variations reported in its phytochemical contents and biological potential. For the first time, the present work is aimed to identify the major phytochemicals present in methanol:chloroform (MC) and petroleum ether (PE) extracts of Curcuma longa rhizome and leaves (by determining polyphenols and GC/MS analysis), and their in-vitro antioxidant and anti-protein denaturation potential. Results showed that the highest value (P < 0.05) of polyphenolic content was in MC extract of rhizome (51.46 ± 0.46 mg GAE/g) followed by 31.20 ± 0.53 mg GAE/g in MC leaves extract. The strong antiradical activity was evaluated in MC extract of rhizome with IC₅₀ value of 92 ± 0.02 µg/mL. MC extracts of both the rhizome and leaves exerted a potent inhibitory effect against protein denaturation with IC₅₀ values of 106.21 ± 0.53 and 108.06 ± 4.67 μg/mL (P > 0.5), respectively. GC/MS analysis showed that α-tumerone was the main component in the rhizome oil (32.44%), whereas in the leaf oil, palmitic acid was the prominent constituent (28.33%) and α-phellandrene recorded a comparable percentage (7.29). In conclusion, C. longa is a valuable source of natural antioxidants and anti-inflammatory constituents, as indicated by its high polyphenolic content and by its considerable in vitro antiradical and anti-protein denaturation potential.

Bio-nanotechnology provided an ecofriendly synthesis route for various metal nanoparticles by utilizing different biological systems, especially microorganisms, which act as an alternative to the physical and chemical methods. Cobalt nanoparticles (CoNPs) were synthesized byPericonia prolifica(Anast.) from intertidal decayed wood samples from the mangrove treeAvicennia marina(Forsk.) of Tarout Island, located in the Arabian Gulf Sea of Saudi Arabia. CoNPs were characterized by X-ray diffraction, transmission electron microscopy, Fourier-transform infrared spectroscopy, and atomic force microscope. The extract of the culture ofP. prolificawas used as a bio-reductant agent, during which the culturing process proved to have great potential to be applied on an industrial scale, as it was a time-saving, inexpensive, and adequate amount of biomass being produced at the end of the process. A preliminary antibacterial test against one Gram-positive resistant bacteria (i.e., Methicillin-resistantStaphylococcus aureus) and other Gram-negative resistant bacteria was performed using a disk diffusion assay. The antibacterial results witnessed the key role that metal size plays in causing higher activity and also in causing severe damage to the bacterial cells by inactivating its membrane permeability, leading to bacterial cell death.

The green synthesis pathway for silver nanoparticles (AgNPs) used in bacterial treatment is regarded as crucial because of its cost-effectiveness, nontoxicity, and eco-friendliness. During the present work, the mangliculous marine fungi Amarenographium solium isolated from the Arabian Gulf Coast of Saudi Arabia were utilized for the synthesis of AgNP, through the bio-reduction of aqueous silver nitrate (AgNO₃) solution. The success in AgNP synthesis was visually identified by the development of dark brown color in the cell-free filtrate and was further confirmed by ultraviolet–visible spectroscopy, which showed a peak at 425 nm. The AgNPs produced were further characterized using X-ray diffraction data analysis that proved the bioreduction of silver to 20 nm, and transmission electron microscopy revealed the formation of well-dispersed spherical nanoparticles with an average mean size of 12 nm. The optimization reaction parameters of temperature, pH, and metal salt concentration were carried out and resulted in a combination of 30°C, 7 and 1.5 mM, respectively, for rapid and maximum yield production. The antibacterial activity of the produced nanoparticles was evaluated using the two-fold microdilution method and showed a minimum inhibitory concentration of 9.375 μg/mL of AgNP against multiple drug-resistant bacterial strains.