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This study aims to explore microbes from mangroves in Saudi Arabia for their abilities to produce high level of lipids. Mangroves are seldom investigated for oleaginous microbes. A total of 961 isolates of yeasts and filamentous fungi were isolated from 144 submerged marine samples include: 68 decaying leaves of Avicennia marina, 33 decaying thalli of Zostera marina, 14 decaying pneumatophores of Avicennia marina, 9 crab shells, 8 sediment, 7 decaying thalli of Turbinaria ornata and 5 decaying thalli of Cystoseira myrica. Samples were collected from four mangrove sites: Al-Leith, Jeddah and Yanbu at the Red Sea coast and the Syhat mangroves at the Arabian Gulf coast. Isolated fungi were grouped into 62 morphological types that include: 21 yeasts and 41 filamentous fungi. Fifty-four isolates of thraustochytrids were cultured from the four mangrove sites and were grouped into 22 strains. Two oleaginous yeasts: Hortaea werneckii and Rhodotorula mucilaginosa and four Aurantiochytrium strains produced high dry weight ranged between 32 and 49.3 g/L of which 35.2–62 % lipid and their fatty acid profile were determined using GC/MS. Palmitic acid was the major fatty acid in the lipid of the four thraustochytrid isolates and ranged between 5.71 and 82 % of the total fatty acids, 9-Octadecenamide, (Z)- was the major fatty acid amide in the lipid of the two yeast isolates and two thraustochytrid isolates and ranged between 26.94 and 56.63 %, followed by 13-Docosenamide, (Z)- (20.44–34.99 %) from the same four isolates. Other major lipid compounds were: Hexadecanamide (4.35–7.19 %), Cholestrol (7.24–15.07 %), Butylated Hydroxytoluene (3.46–15.76 %), Octadecanamide (3.95–7.9 %), Phenol, 2-(1,1-dimethylethyl)-5-methyl- (1.78–10.33 %) and Pentadecanoic acid (7.47 %).

This study explores low-cost substrates for the production of high biomass, lipid and DHA by local native strain of thraustochytrid that was isolated from decaying leaves of Avicennia marina collected from Yanbu mangroves along the Red Sea coast of Saudi Arabia. Molecular phylogenetic analyses based on 18S rDNA sequences placed the thraustochytrid strain (YB-05) in the Aurantiochytrium. The studied strain was grown on three different types of raw material available in the local market and compared to pure glucose for high biomass, lipid and DHA production. Aurantiochytrium sp. YB-05 was grown on: date fruit, glycerol, cane molasses and pure glucose at four concentrations: 10, 20, 40 and 80 g/L. Produced dry cell weight increased as the carbon sources: date fruit, molasses and glucose increased from 10 to 80 g/L. Both date fruit and molasses gave a higher biomass than pure glucose and glycerol at 40 and 80 g/L concentration, while glucose gave higher biomass at 10 and 20 g/L than the other three carbon sources. Date fruit gave the highest biomass (42.6 g/L) at the 80 g/L concentration and also increased the level of DPA (decosapentaneoic acid) and DHA from 0.64 and 4.89% TFA (total fatty acids) with glucose to 7.13 and 24.85% with date fruit respectively. Ten g/L glycerol gave the highest percentage of lipids (85.6% of the biomass), followed by 40 g/L glucose (80.1%), 20 g/L glycerol (70%), 80 g/L glucose (59.3%) and 80 g/L date fruit (56.4%). The percentage of lipid in the biomass increased with increasing the weight of date fruit and molasses from 10 g/L (24.7% and 15.6% respectively) to 80 g/L (56.4% and 45.7% respectively). This study shed a light on the potential use of date fruits for the production of value-added products using microbes. Saudi Arabia is the second largest date producer in the world after Egypt. The present research also studied the effect of four types of oily seeds in a combination with date fruit on the production oil, DHA and the major fatty acids produced by Aurantiochytrium sp. YB-05. The fatty acid profile of Aurantiochytrium sp. YB-05 grown on date palm, pure glucose and seeds were determined.

This is the first report of thraustochytrids from Saudi Arabia. A total of 108 isolates of thraustochytrid were cultured from Syhat mangroves, Arabian Gulf, Saudi Arabia. Isolated thraustochytrids belonged to five genera: Aplanochytrium, Aurantiochytrium, Schizochytrium, Thraustochytrium and Ulkenia. Cultured thraustochytrids isolated from decaying leaves of Avicennia marina (77 isolates), sediment (15), seawater (10) and decaying thalli of Sargassum (6). Of the 108 isolates, three strains (SY25, SY38 and SY52) were selected based on their high biomass productivity and high percentages of PUFAs. Phylogenetic analyses based on 18S rDNA placed the three strains within the Aurantiochytrium clade with high statistical support. Species of Aurantiochytrium formed six separate clades, the two strains (SY38 and SY52) formed a separate clade that is a sister clade to the one that contains the type species A. limacinum, while SY25 grouped with Aurantiochytrium sp. TA4, that is also isolated from mangroves in Iran, Arabian Gulf. The strains (SY38 and SY52) shared the phylogenetic placement, their morphology and fatty acid profile. The strain SY25 have different shape of sporangia that divide to give zoospores directly, sporogenous cells are surrounded by thick gelatinous sheath and produce high levels of Linoleic and Oleic essential unsaturated fatty acids. The three studied strain produced high levels of Palmitic acid (ranged between 31.1 and 65.3 % of total fatty acids) that can be further optimized for biofuel production.

This study is to evaluate the potential of endophytic fungi of Salvadora persica for the production of bioactive compounds against pathogenic bacteria and fungi. Forty-two fungal isolates were obtained from 135 young and old stem and 125 root segments. Those 42 isolates representing ten fungi include: Trichoderma sp. (the most common), two species of Alternaria, Rhizopus arrhizus and 6 sterile mycelia. The ten fungi were grown in liquid culture and their crude extracts were tested against pathogenic bacteria and fungi. Nine crude extracts gave positive reactions against pathogenic bacteria of which Alternaria sp. (A8) was chosen further study. The fungal isolate was growing as sterile mycelium and was identified by phylogenetic analyses based on LSU rDNA sequence data and it might represent undescribed species of Alternaria. Sixty-two bioactive chemical compounds were identified from the ethyl acetate crude extracts of Alternaria sp., of which the following were recorded as major compounds in the active sub-fractions. These compounds showed strong antibacterial activity in combination. Keywords: Arabian Peninsula, Antibacterial, Pleosporaceae, Molecular phylogeny

Cationic dye (methylene blue) and anionic dye (carmine) degradation were demonstrated by SrO and G-SrO NPs. Furthermore, the carmine dye was degraded using two promising technologies: photocatalysis and electro& photo-electrocatalytic oxidation. Analyses of the synthesized photocatalysts were carried out utilizing optical techniques such as Fourier transforms infrared (FTIR), X-ray diffraction (XRD), UV–visible absorption, and Scanning Electron Microscopy (SEM). The FTIR results showed that no band for graphene appeared. The XRD data revealed that the nanocomposite has a cubic structure typical of SrO, which is highly crystalline. The energy band gap (EBG) decreases from 6 eV to 3.87 eV for SrO and 0.25 G-SrO, respectively. SEM images showed that incorporating graphene into SrO might enhance the surface area.For photocatalytic applications, the results revealed that the 0.25G-SrO catalyst achieved 99.5% degradation of MB dye and kinetic degradation rates of 0.04718 min−1 within 70min by photocatalysis under UV light irradiation. In comparison, 0.1G-SrO catalyst reached 79.03% degradation of carmine and kinetic degradation rates of 0.01182 min−1 within 125 min. The carmine dye was completely degraded with 8 min and 6 min irradiation time by electro and photo-electro catalytic. According to this research, SrO's photocatalytic activity was improved by incorporating graphene under UV light; besides comparing photocatalysis and electro &photo-electro catalytic processes to verify which technique is best for treating carmine in effluents.

Yttrium oxide/CuO nanocomposite with different concentrations of Y2O3 were synthesized by a combustion technique. The structural, morphology, and photocatalytic properties were investigated using X-ray diffraction, SEM and photodegradation studies respectively. Scanning electron microscopy images reveal the porous nanocomposite morphology with significant aggregation. The photocatalyst degraded both carmine and methylene blue (MB). An attempt was made to discover the optimal circumstances of degradation, including time of contact, H2O2 concentration, and light exposure. Under UV irradiation, 2.5% Y2O3 -CuO nanocomposite demonstrated optimum photocatalytic efficiency of up to 55.68% in 70 min, with a rate constant of around 0.0079 min−1 for MB. However, the photocatalytic efficiency of the 1% Y2O3/CuO nanocomposite increased to 87.95% in 70 min, with a rate constant of about 0.01826 min−1 for carmine under UV irradiation. The findings demonstrated that UV light increased the reaction rate more than visible light. Furthermore, the research showed that carmine is degraded faster than MB. Cyclic experiments showed the Y2O3/CuO nanocomposite stability over repeated use. The photocatalytic reaction species trapping studies were performed with 1% Y2O3/CuO nanocomposite and UV light.

Herein, the proposed work reports a simple chemical approach; solution combustion method to synthesize ZnO nanoparticles and Nd-doped ZnO (Nd2O3-ZnO) nanocomposites (0.001 g–5 g) using the combustion technique. The combustion approach is considered one of the environmentally friendly, cost-effective, high yields, and most straightforward procedures for rapidly preparing nanomaterials on a large scale. The prepared nano samples were characterized through standard analytical methods, including scanning electron microscopy (SEM), X-ray Diffraction (XRD), UV–Vis–NIR, and Fourier transform infrared spectroscopy. The XRD results and SEM image showed that the manufactured Nd2O3–ZnO nanostructured samples were crystalline with uniform distribution of Nd dopants on the host ZnO samples, clear with higher Nd concentration ratios. Moreover, as the Nd was raised in the Nd2O3–ZnO nanostructures, the direct energy bandgap values of the Nd: ZnO nanocomposites were detected to decline from 3.35 eV for pure ZnO to reach 3.26 eV, and the indirect bandgap diminished from 3.28 eV to 3.20 eV. All prepared Nd2O3–ZnO samples were applied for photocatalytic degradation of Rhodamine B, Methylene Blue, and both. The photocatalytic efficiency increased with the Nd doping ratio. The best photocatalyst is 0.5 g Nd2O3 doped-ZnO, which degrades Methylene Blue, Rhodamine B, and combination solutions containing both dyes with 100% against ZnO alone with 80% within 60 min under the visible light. Compared to the pure ZnO nanoparticles, the synthesized Nd2O3–ZnO nanostructured samples disclosed improvements in the structural morphology, optical, energy bandgaps, dielectric refraction, and electrical and photocatalytic properties.

Chronic stress is a universal condition commonly associated with many psychiatric diseases. An extensive body of evidence discussed hippocampal affection upon chronic stress exposure, however, the underlying molecular pathways still need to be identified. We investigated the impact of chronic stress on miR200/BMP/Olig‐2 signaling and hippocampal myelination. We also compared the effects of chronic administration of amitriptyline and cholecalciferol on chronically stressed hippocampi. Both amitriptyline and cholecalciferol significantly decreased serum cortisol levels, reduced immobility time in the forced swim test, increased the number of crossed squares in open field test, decreased the hippocampal expression of bone morphogenetic protein 4 (BMP4) and its messenger RNA (mRNA) levels, reduced miR200 expression as compared to untreated chronically stressed rats. Also, both drugs amended the hippocampal neuronal damage, enhanced the surviving cell count, and increased the pyramidal layer thickness of Cornu Ammonis subregion 1 (CA1) and granule cell layer of the dentate gyrus. Cholecalciferol was more effective in increasing the area percentage of myelin basic protein (MBP) and Olig‐2 positive cells count in hippocampi of chronic stress‐exposed rats than amitriptyline, thus enhancing myelination. We also found a negative correlation between the expression of BMP4, its mRNA, miR200, and the immunoexpression of MBP and Olig‐2 proteins. This work underscores the amelioration of the stress‐induced behavioral changes, inhibition of miR200/BMP4 signaling, and enhancement of hippocampal myelination following chronic administration of either amitriptyline or cholecalciferol, though cholecalciferol seemed more effective in brain remyelination. [ABSTRACT FROM AUTHOR]

The radiation-protection properties of the magnetic semiconducting quaternary compounds Cu2CoGeS4, Cu2CoGeSe4, and Cu2CoGeTe4 were examined in this study by using Phy-X/PSD software with the selected gamma energy (0.015–15 MeV). The radiation shielding coefficients such as mass and linear attenuation coefficients (MAC) and (LAC), half-value layer (HVL), and mean free path (MFP) of the present semiconductors were calculated. Also, the total electronic and atomic cross-sections (ECS and ACS), the effective atomic number (Zeff), the effective electron density (Neff), and the effective conductivity (Ceff) of these semiconductors were estimated to see how well they could protect against radiation. A comparative study occurred between the obtained results and the corresponding values of RS-253-G18, RS-360, RS-520 glasses, barite, chromite, and ferrite concrete. The results show that semiconducting samples with the best shielding performance outperform RS-253-G18, RS-360 glass, and RS-520 glass materials commonly used in nuclear applications. The Cu2CoGeTe4 sample had the highest MAC, LAC, and ACS, as well as the highest ECS and Zeff values. The other two semiconductor samples had the lowest MAC, ECS, and Zeff values. For photons, charged particles (electrons, protons, alpha particles), and C-ion, Phy-X/PSD allows the calculation of the Zeff quickly and precisely across the entire energy range. This study indicates that the semiconductor samples can be utilized as radiation attenuators for various nuclear fields.

Three-dimensional (3D) printing is one of the most futuristic manufacturing technologies, allowing on-demand manufacturing of products with highly complex geometries and tunable material properties. Among the different 3D-printing technologies, fused deposition modeling (FDM) is the most popular one due to its affordability, adaptability, and pertinency in many areas, including the biomedical field. Yet, only limited amounts of materials are commercially available for FDM, which hampers their application potential. Polybutylene succinate (PBS) is one of the biocompatible and biodegradable thermoplastics that could be subjected to FDM printing for healthcare applications. However, microbial contamination and the formation of biofilms is a critical issue during direct usage of thermoplastics, including PBS. Herein, we developed a composite filament containing polybutylene succinate (PBS) and lignin for FDM printing. Compared to pure PBS, the PBS/lignin composite with 2.5~3.5% lignin showed better printability and antioxidant and antimicrobial properties. We further coated silver/zinc oxide on the printed graft to enhance their antimicrobial performance and obtain the strain-specific antimicrobial activity. We expect that the developed approach can be used in biomedical applications such as patient-specific orthoses.

An efficient and environmentally friendly combustion technique was employed to produce ZnO nanopowders with different Eu concentrations (from 0.001 g to 5 g). The structural morphology of the Eu2O3-ZnO nanocomposites was examined using XRD, SEM, and infrared spectroscopy (FT-IR). In addition, UV-Vis diffuse reflectance spectroscopy was also used to investigate the effects of europium (Eu) dopant on the optical behaviors and energy bandgaps of nano-complex oxides. The photocatalytic degradation efficiency of phenol and methylene blue was investigated using all the prepared Eu2O3-ZnO nanostructured samples. Photocatalytic effectiveness increased when europium (Eu) doping ratios increased. After adding moderate Eu, more hydroxyl radicals were generated over ZnO. The best photocatalyst for phenol degradation was 1 percent Eu2O3-ZnO, while it was 0.5 percent Eu2O3-ZnO for methylene blue solutions. The obtained Eu2O3-doped ZnO nanostructured materials are considered innovative, promising candidates for a wide range of nano-applications, including biomedical and photocatalytic degradation of organic dyes and phenol.

The goal of this study was to synthesize a UV-light-active ZnO photocatalyst by modifying it with nitrogen and graphene, then applying it to the degradation of carmine dye utilizing two promising technologies: photocatalysis and electrochemical oxidation (E.O.). Different techniques were used to analyze the prepared photocatalysts, such as Fourier transform infrared (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD). According to XRD measurements, the produced nanocomposite possesses a hexagonal wurtzite structure, indicating ZnO and markedly crystalline. For photocatalytic applications, the results revealed that the 0.001 g of G/N-doped ZnO catalyst achieved 66.76% degradation of carmine and kinetic degradation rates of 0.007 min−1 within 185 min by photocatalysis under UV light irradiation. In comparison, the same sample reached 100% degradation of carmine and kinetic degradation rates of 0.202 min−1 within 15 min using the electrochemical oxidation method. The improved photocatalytic activity of as-produced nanocomposites can be attributed to intermediate levels in the prohibited bandgap energy and the enhanced oxygen vacancies caused by nitrogen doping. The electrolyte (NaCl) on the degradation of the carmine dye was tested, and the findings indicated that the dye molecules were photodegraded by the 0.001 g of G/N-doped ZnO nanocomposite after a 15 min time interval. The data presented in this work for the carmine breakdown in water give intriguing contrasts between photocatalytic, indirect electrochemical oxidation, and photoelectrochemical oxidation. The action of chlorinated oxidative species, predominantly HClO, which were electrogenerated at the electrode surface due to the chloride ion’s oxidation in solution, induced indirect electrochemical oxidation degradation. This study also revealed that the modifications made to ZnO were beneficial by improving its photocatalytic activities under UV light, as well as a comparison of photocatalysis and electrochemical oxidation processes to determine which technique is best for treating carmine in effluents with high chloride ions.

The incorporation of tungsten trioxide (WO3) by various concentrations of graphitic carbon nitride (g-C3N4) was successfully studied. X-ray diffraction (XRD), Scanning Electron Microscope (SEM), and Diffused Reflectance UV-Vis techniques were applied to investigate morphological and microstructure analysis, diffused reflectance optical properties, and photocatalysis measurements of WO3/g-C3N4 photocatalyst composite organic compounds. The photocatalytic activity of incorporating WO3 into g-C3N4 composite organic compounds was evaluated by the photodegradation of both Methylene Blue (MB) dye and phenol under visible-light irradiation. Due to the high purity of the studied heterojunction composite series, no observed diffraction peaks appeared when incorporating WO3 into g-C3N4 composite organic compounds. The particle size of the prepared composite organic compound photocatalysts revealed no evident influence through the increase in WO3 atoms from the SEM characteristic. The direct and indirect bandgap were recorded for different mole ratios of WO3/g-C3N4, and indicated no apparent impact on bandgap energy with increasing WO3 content in the composite photocatalyst. The composite photocatalysts’ properties better understand their photocatalytic activity degradations. The pseudo-first-order reaction constants (K) can be calculated by examining the kinetic photocatalytic activity.

The growth of the textile industry results in a massive accumulation of dyes on water. This enormous rise in pigments is the primary source of water pollution, affecting the aquatic lives and our ecosystem balance. This study aims to notify the fabrication of neodymium incorporated copper oxide (Nd2O3 doped CuO) nanoparticles by combustion method for effective degradation of dye, methylene blue (MB). X-ray diffraction (XRD), Field emission Scanning electron microscopy (FESEM), Zeta potential have been applied for characterization. Photocatalyst validity has been evaluated for methylene blue degradation (MB). Test conditions such as time of contact, H2O2, pH, and photo-Fenton have been modified to identify optimal degradation conditions. Noticeably, 7.5% Nd2O3 doped CuO nanoparticle demonstrated the highest photocatalytic efficiency, up to 90.8% in 80 min, with a 0.0227 min−1 degradation rate. However, the photocatalytic efficiency at pH 10 becomes 99% with a rate constant of 0.082 min−1. Cyclic experiments showed the Nd2O3 doped CuO nanoparticle’s stability over repeated use. Scavenge hydroxyl radical species responsible for degradation using 7.5% Nd2O3 doped CuO nanoparticles have been investigated under visible irradiation.

A pot experiments was carried out to evaluate the influence of growing media and combined treatments of NPK with either benzyladenine or gibberellic acid on growth, chemical constituents and anatomical structure of Dracaena marginata ‘Bicolor’. The plants were grown in two growing media; peat-moss, peat-moss+ sand (1:1, v v-1), received monthly NPK fertilizers (2 and 4 g pot-1) combined with either of benzyl adenine (BA) at 100 and 150 ppm or gibberellic acid (GA3 ) at 150 and 250 ppm, while the control plants received no treatments. As general, the results indicated that, peat- moss was superior to peat-moss+ sand medium on increasing most of vegetative growth parameters in terms of plant height, number of leaves/plant, leaf area, root length, as well as fresh and dry weights of leaves, stems and roots/plant, besides some macro elements represented in N, P, K, Ca and Mg% in both leaves and stems. While plants grown in peat-moss+ sand possessed significantly higher contents of total chlorophylls, total carbohydrates, Cu, Fe, Mn, Zn and B than those grown in peat- moss alone. Plants received combined NPK with either BA or GA3 resulted in significant increases in most of morphological and chemicals content over the control plants and it was outstanding that, GA3 was more effective than BA when they were combined with NPK. It can be concluded that for the highest quality, quantity growth and economic production of Dracaena marginata ‘Bicolor’, the plants could be grown in a medium of peat-moss and supplied monthly with NPK fertilizer at 2 g plant-1 along with foliar sprayed with 250 ppm GA3.