Mervat Gameel Hassan

The green production of metal oxide nanoparticles using plant extracts has received the attention of researchers. In this work, we produced aluminum oxide nanoparticles (Al₂O₃-NPs) using Aloe vera leaf extract to stabilize and reduce them. UV–Vis spectroscopy showed a substantial absorption peak at about 300–320 nanometers, confirming nanoparticle production. The developed material had a nanocrystalline structure, as seen based on several sharp XRD peaks that matched crystalline aluminum oxide material. Functional groups such as C=O, O–H, and Al–O were identified using Fourier transform infrared spectroscopy (FT-IR). Zeta potential analysis of an Al₂O₃ nanoparticle solution exhibited a continuous, low-frequency signal. The particle size distribution was narrow, with an average hydrodynamic diameter of 1000–1200 nanometers, according to DLS tests. Uneven nanoparticles formed platelet-like agglomerations in SEM pictures. Energy dispersive X-ray spectroscopy revealed aluminum and oxygen nanoparticles. SAED patterns indicated polycrystalline nanoparticles, whereas TEM exhibited uneven layers and mesoporousness. A GC-MS analysis of the Aloe vera extract revealed various bioactive chemicals that are known to have the ability of reduction and potential for stabilizing nanoparticles. The biosynthesized Al₂O₃-NPs exhibited antioxidant activity, with IC₅₀ values of 20.12 µg/mL for DPPH, 20.34 µg/mL for ABTS, and 45.99 µg/mL for H₂O₂ scavenging. However, the relatively higher IC₅₀ value of 96.06 µg/mL observed in normal WI-38 lung fibroblast cells indicates comparatively lower cytotoxicity toward normal cells, while further studies are needed to optimize and confirm the selectivity of the nanoparticles. Cytotoxicity assays revealed strong anticancer activity against A549 lung carcinoma cells (12.24 µg/mL) and HepG2 liver cancer cells (15.65 µg/mL). The nanoparticles exhibited substantial suppression against Klebsiella pneumoniae (K. pneumoniae ATCC 43816) and multidrug-resistant Proteus vulgaris (P. vulgaris ATCC 6380), but moderate to no action against P. aeruginosa, L. monocytogenes, and Staphylococcus. In-silico molecular docking showed that 9-octadecenoic acid (Z)-, methyl ester, the main Aloe vera phytoconstituent, may interact with heme oxygenase, contributing to its antioxidant effect.

Rechargeable magnesium batteries are promising candidates for next-generation energy storage systems due to their intrinsic safety, natural abundance, and high volumetric capacity. However, their practical application remains limited by sluggish Mg²⁺ transport, electrolyte instability, and low cathode utilization. In this work, a halogen-free electrolyte (HFE) based on Mg(NO₃)₂ in an acetonitrile/tetraethylene glycol dimethyl ether (ACN/G4) solvent system is modified using the ionic liquid 1-ethyl-3-methylimidazolium acetate ([EMIM][OAc]) to form HFE_IL, with the aim of enhancing ionic transport and interfacial stability. In parallel, a sustainable sulfur cathode integrated with microalgae-derived hard carbon (S_C) is developed to improve electronic conductivity and suppress polysulfide shuttling. Structural and spectroscopic analyses confirm that the incorporation of the ionic liquid preserves the electrolyte framework while tuning the solvation environment. Electrochemical characterization (EIS, CV, LSV, GCD, and Mg stripping/plating measurements) reveals that HFE_IL exhibits reduced bulk and interfacial resistances, a significantly lower activation energy (0.0173 eV compared to 0.14 eV), and an increased Mg²⁺ transference number (~0.8). Furthermore, enhanced Mg²⁺ diffusion (~10⁻¹³ cm² s⁻¹) and improved charge-transfer kinetics are achieved compared to the pristine electrolyte. Symmetric Mg‖Mg cells demonstrate stable stripping/plating behavior with reduced polarization over 100 h. In full Mg‖electrolyte‖S_C cells, the HFE_IL system delivers a higher discharge capacity (~575 mAh g⁻¹) compared to the pristine electrolyte (~437 mAh g⁻¹), indicating improved reversibility and Mg²⁺ utilization. This study demonstrates that ionic-liquid modification of halogen-free electrolytes, combined with sustainable carbon–sulfur cathodes, provides an effective strategy to enhance Mg²⁺ transport, interfacial stability, and overall electrochemical performance in magnesium batteries.

Marine associated fungi were isolated from marine sponges collected at two ecologically distinct localities in Hurghada. Macroscopic characteristics were e

The genus Streptomyces has been recently proven to be a valuable and rich source of producing several bioactive compounds with substantial biological activity and applications in many fields such as medicine, environmental science, food industries, and agronomy. This study highlights the importance of Streptomyces as an antimicrobial, antibiofilm, and anticancer. Out of the 75 actinobacteria isolated from both marine and soil habitats, one isolate, HG2, was selected based on its potent antimicrobial activity. The isolate has been identified morphologically by studying colony and spore chain morphology using TEM and genetically by sequencing their 16 sr RNA gene as Streptomyces sp. 22SH with Accession number OK326829.1. Bioassay-guided fractionation of the Streptomyces sp. 22SH crude extract led to the isolation and purification of Cis-9-Octadecenoic. Biological evaluation including antimicrobial and antibiofilm activity of the crude and purified compound was performed on four clinical microbes (S. aureus ATCC6538-P, B. subtilis ATCC6633, and P. aeruginosa ATCC27853). The compound showed the ability to eradicate the biofilm formation by the tested pathogens. Additionally, the antitumor activity was assessed, and the compound showed a cytotoxic effect against liver carcinoma and breast cancer cells, with IC50 values of 17.48 ± 0.94 and 88.73 ± 4.78 µg/ml, respectively. While it displayed anti-topoisomerase activity with an IC₅₀ of 0.65 ± 0.023 µg/ml. Furthermore, the compound’s ADME-related physicochemical features and docking analysis were investigated.

Marine samples were collected from the Red Sea beach in Hurghada, Egypt, and processed within 24 hours. A total of 20 bacterial isolates were obtained from water samples and coded accordingly. These isolates were cultured in SP2 media for small-scale fermentation, and bioactive compounds were extracted using ethyl acetate. The crude extracts were tested for antimicrobial and antifungal activities against Escherichia coli, Staphylococcus aureus, Aspergillus niger, and Candida albicans.Antimicrobial screening revealed that all 20 isolates exhibited inhibitory effects against E. coli and S. aureus, with H1 demonstrating the highest inhibition (85.34%) against S. aureus. The antifungal activity assessment indicated that Es1 was the most potent against Aspergillus niger (81.78%), while B3 showed the highest activity against Candida albicans (82.7%) . These findings highlight the potential of marine bacteria as sources of bioactive compounds with promising antimicrobial and antifungal properties, warranting further characterization and optimization for potential pharmaceutical applications .

Soil microbial communities play a crucial role in biotechnological applications, particularly in the process of making nanoparticles. Soil samples were obtained for this investigation from two different areas in Benha (SO1 and SO2) to isolate bacterial strains capable of synthesizing silver nanoparticles (AgNPs). There were ten of bacterial isolates collected, with six from SO1 and four from SO2. The ability of these isolates to synthesize AgNPs was assessed based on color change, indicating nanoparticle formation. Among them, SDO6 exhibited the highest biosynthetic activity (+++), suggesting a strong potential for silver ion reduction and nanoparticle stabilization.The antibacterial ability of biosynthesized AgNPs from SDO6 was tested against Escherichia coli and Staphylococcus aureus, using ciprofloxacin (5 µg/mL) as a standard antibiotic. The results showed significant antibacterial effects, with an inhibition rate of 89.025% against E. coli, though slightly lower than ciprofloxacin (99.05%). In contrast, AgNPs exhibited a weaker inhibitory effect against S. aures (40.12%), compared to ciprofloxacin (98.25%). The higher susceptibility of E. coli suggests that AgNPs interact more effectively with Gram-negative bacterial membranes, leading to oxidative stress and cell disruption. The lower efficacy against S. aureus may be attributed to its thick peptidoglycan layer, this layer serves as a barrier against nanoparticle penetration.

The present study focuses on the isolation of Saccharomyces spp. from bakery yeast samples and their potential for biosynthesizing silica nanoparticles (SiNPs) with antibacterial properties. Yeast samples were collected from four different bakeries in Benha to ensure strain diversity, and multiple isolates were successfully obtained. Screening for silica nanoparticle biosynthesis revealed significant variations among the isolates, with DO1S4 and DO4S1 exhibiting the highest biosynthesis potential (+++), indicating strong enzymatic activity and effective interaction with silica precursors. Moderate biosynthesis (++) was observed in isolates DO1S1 and DO2S3, while several isolates showed weak or no biosynthesis activity. The antibacterial activity of SiNPs synthesized from the highly active strain DO1S4 was evaluated against Escherichia coli and Staphylococcus aureus. The biosynthesized SiNPs demonstrated significant antibacterial effects, with inhibition rates of 77.025% against E. coli and 52.02% against S. aureus. However, their efficacy was lower than ciprofloxacin (5 µg/mL), which exhibited inhibition rates of 99.05% and 98.25%, respectively. The enhanced effect against E. coli compared to S. aureus is likely due to differences in bacterial cell wall structures, affecting nanoparticle penetration and antimicrobial efficiency. The antibacterial activity of the biosynthesized SiNPs is attributed to mechanisms such as reactive oxygen species (ROS) generation,

Probiotics are living microorganisms that, when given in an adequate dose, have a healthy impact on human well-being. With global interest in self-care, dietary supplements especially probiotics is expanding rapidly due to their supported health effects. In this study, a total of twenty-two samples were collected from dairy products in Egypt’s markets, firstly isolated then identified and screened for probiotic properties under stressful conditions as NaCl, acid and bile salt conditions. After evaluation of the antimicrobial effect against widespread gram negative and gram positive human infecting bacteria, besides the antiviral assessment against (SARS-CoV-2) virus which has disturbed the world, the antibiotic susceptibility test was done. Only three promising isolates were subjected for whole genome sequence with high-output next generation technology and the obtained data was subjected to a full bioinformatics analysis. The results obtained stated the advance of our isolates to tolerate the stress factors that can struggle in the human gut as well as the antimicrobial effects. All these bright characteristics were confirmed and illustrated in detail through different and reliable genome analysis tools. Our isolates were founded to have stable genome through containing mobile genetic elements like phages and CRISPR clusters that confirm the safety and quality for human health.