14 results on '"El-Hefnawy ME"'
Search Results
2. Inhibition of Drp1 orchestrates the responsiveness of breast cancer cells to paclitaxel but insignificantly relieves paclitaxel-related ovarian damage in mice.
- Author
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Alalawy AI, Sakran M, Alzuaibr FM, Alotaibi MA, El-Hefnawy ME, Hazazi AY, El-Gendy SM, Aidy EA, Effat H, Ismail DF, and Hessien M
- Subjects
- Humans, Animals, Mice, Female, Paclitaxel pharmacology, Paclitaxel therapeutic use, Cisplatin pharmacology, Drug Resistance, Neoplasm, Apoptosis, Hormones pharmacology, Cell Line, Tumor, Breast Neoplasms drug therapy, Breast Neoplasms genetics, Ovarian Neoplasms genetics
- Abstract
Chemoresistance and chemotherapy-related ovarian damage are well-reported in breast cancer (BC) young patients. Herein, the inhibition of the mitochondrial fission was invested to explore its chemosensitizing role in Paclitaxel (PTX)-resistant cells, and its ability to restore the ovarian integrity in mice receiving PTX or cisplatin chemotherapy. To establish these aims, PTX-resistance was generated in BC cells, which were treated with PTX in combination with Drp1 deficiency, via mdivi-1, or Drp1-specific siRNA transfection. Furthermore, the alterations in the ovarian structure and the endocrine-related hormones were explored in mice receiving repetitive doses of PTX or cisplatin. We found that combining PTX with mdivi-1 improved cell responsiveness to PTX, induced apoptosis- and autophagy-mediated cell death, and relieved cellular oxidative stress. Additionally, the expression of PCNA1 and cyclin B1 genes were downregulated, meanwhile, p53, p21, and mitochondrial fusion proteins (Mfu1&Mfu2) were increased. The in vivo investigations in mice demonstrated that PTX induced gonadotoxic damage similar to cisplatin, whereas dual treatment of mice with PTX+ mdivi-1 failed to restore their normal follicular count and the circulating levels of E2 and AMH hormones. These results suggested that combining Drp1 inhibition with PTX resensitized breast cancer cells to PTX but failed to offer enough protection against chemotherapy-related gonadotoxicity., (© 2023. The Author(s).)
- Published
- 2023
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3. The blockage signal for PD-L1/CD274 gene variants and their potential impact on lung carcinoma susceptibility.
- Author
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Sakran MI, Alalawy AI, Alharbi AA, El-Hefnawy ME, Alzahrani SM, Alfuraydi A, Alzuaibr FM, Zidan NS, Elsaid AM, Toraih EA, and Elshazli RM
- Subjects
- Humans, B7-H1 Antigen genetics, B7-H1 Antigen metabolism, Programmed Cell Death 1 Receptor genetics, Lung pathology, Lung Neoplasms, Carcinoma
- Abstract
Background: The programmed death-ligand 1 (PD-L1/CD274) gene plays a key function in suppressing anti-tumor immunity through binding to its receptor PD-1 on stimulated T lymphocytes. However, robust associations among diverse populations and lung susceptibility remain unclear. The tentative purpose of this research is to investigate whether PD-L1/CD274 polymorphisms modulate susceptibility to lung carcinoma using totalitarian techniques, including genetic analysis, and sophisticated bioinformatic methods., Methods: PD-L1/CD274 (rs822336, rs2297136, and rs4143815) variants were genotyped in 126 lung carcinoma cases and 117 healthy controls using tetra-primer ARMS-PCR. Logistic regression and bioinformatics analyses assessed genetic associations., Results: The rs2297136 GA genotype significantly increased lung cancer risk by 3.7-fold versus GG genotype (OR 3.69, 95 % CI 1.39-9.81, p = 0.016), with the minor A allele also increasing risk (OR 1.47, p = 0.044). In contrast, the rs4143815 CC genotype was associated with 70 % decreased cancer risk versus GG (OR 0.30, 95 % CI 0.11-0.87, p = 0.012), although the minor C allele itself was not significant. The rs822336 variant showed no association. Haplotype and multivariate analyses supported these findings. In silico predictions suggested functional impacts on PD-L1 expression and activity., Conclusions: This study identified novel associations between PD-L1/CD274 polymorphisms and susceptibility to lung cancer in Egyptians. The rs2297136 variant increased risk while the rs4143815 variant conferred protection, highlighting the PD-1/PD-L1 axis as a potential biomarker and therapeutic target in lung oncogenesis. Replication in larger cohorts and functional studies are warranted., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)
- Published
- 2023
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4. Fabrication of bioactive nanocomposites from chitosan, cress mucilage, and selenium nanoparticles with powerful antibacterial and anticancerous actions.
- Author
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El-Sherbiny MM, Orif MI, El-Hefnawy ME, Alhayyani S, Al-Goul ST, Elekhtiar RS, Mahrous H, and Tayel AA
- Abstract
Natural bioactive alternatives are the utmost requests from researchers to provide biosafe and effectual health-guarding agents. The biopolymers chitosan nanoparticles (NCT), mucilage of cress seed (GCm; Lepidium sativum ), and GCm-mediated selenium nanoparticles (GCm/SeNPs) were innovatively employed for fabricating novel bioactive natural nanocomposites (NCs) with elevated bioactivities as bactericidal (against Salmonella typhimurium and Staphylococcus aureus ) and anticancer (against CaCo-2 and HeLa cells). The SeNPs were successfully generated with GCm, and different NCs formulations were fabricated from NCT:GCm/SeNPs amalgam ratios including T1, T2, and T3 with 2:1, 1:1, and 1:2 ratios, respectively. The infrared analysis of synthesized molecules appointed apparent physical interactions among interacted molecules. The average particles' sizes and charges of molecules/NCs were (12.7, 316.4, 252.8, and 127.3 nm) and (-6.9, +38.7, +26.2, and -25.8 mV) for SeNPs, T1, T2, and T3, respectively. The biocidal assessment of NCs indicated that T1 was the strongest antibacterial formulation, whereas T3 was the superior anticancer amalgam. These NCs formulations could exceed the biocidal potentialities of standard biocides. T1-NC could cause severe destructions/deformations in challenged S. typhimurium within 9 h, whereas T3-NCs induced apparent fluorescent apoptosis signs in treated HeLa cells. The prospective applications innovatively designed biocidal natural NCs that are recommended for controlling pathogenic bacteria and fighting cancerous cells., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 El-Sherbiny, Orif, El-Hefnawy, Alhayyani, Al-Goul, Elekhtiar, Mahrous and Tayel.)
- Published
- 2023
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5. Preparation of afterglow and photochromic fibrous mats from polypropylene plastics to detect ultraviolet light.
- Author
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El-Hefnawy ME, Ismail AI, Orif MI, Al-Goul ST, Elmushyakhi A, and Abou Taleb M
- Subjects
- Polypropylenes, Ultraviolet Rays, Plastics, Nanoparticles
- Abstract
Polypropylene textiles have been used in the development of various industrial products, such as automotives, plastic furniture, and medical tools. However, polypropylene resists dyeing due to a deficiency of active staining spots. Here, we developed a new strategy towards new afterglow and photochromic fibres from recycled polypropylene plastics using plasma-supported coloration with rare-earth activated aluminate nanoparticles (REANPs). Plasma curing was used to generate active dyeing sites on the polypropylene surface. A thin film of REANPs (2-10 nm) was deposited onto the plasma-pretreated polypropylene surface. Various analytical techniques were applied to inspect the morphology of the REANP-finished polypropylene fibres. The polypropylene dyeing activity was much improved after being exposed to plasma. Both photoluminescence analysis and Commission internationale de l'éclairage (CIE) laboratory coordinates proved that the polypropylene fibres exhibited a white colour in daylight and green in ultraviolet light. The thin afterglow layer immobilized onto the polypropylene surface exhibited an emission band of 524 nm upon excitation at 365 nm. The sliding angles dropped from 12° to 9°, but the contacting angles increased from 139.4° to 145.0° when the REANP ratio was raised. These findings show that REANP-finished polypropylene had good colourfastness, antimicrobial activity, and ultraviolet light blocking. Both stiffness and permeability to air of REANP-finished polypropylene were explored to designate excellent comfort characteristics., (© 2023 John Wiley & Sons, Ltd.)
- Published
- 2023
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6. Facile Synthesis, Characterization, and Antimicrobial Assessment of a Silver/Montmorillonite Nanocomposite as an Effective Antiseptic against Foodborne Pathogens for Promising Food Protection.
- Author
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El-Sherbiny MM, Devassy RP, El-Hefnawy ME, Al-Goul ST, Orif MI, and El-Newehy MH
- Subjects
- Animals, Silver pharmacology, Silver chemistry, Bentonite pharmacology, Bentonite chemistry, Anti-Bacterial Agents pharmacology, Anti-Bacterial Agents chemistry, Microbial Sensitivity Tests, Bacteria, X-Ray Diffraction, Anti-Infective Agents, Local pharmacology, Metal Nanoparticles chemistry, Nanocomposites chemistry
- Abstract
Foodborne pathogens can have devastating repercussions and significantly threaten public health. Therefore, it is indeed essential to guarantee the sustainability of our food production. Food preservation and storage using nanocomposites is a promising strategy. Accordingly, the present research's objectives were to identify and isolate a few foodborne pathogens from food products, (ii) synthesize and characterize silver nanoparticles (AgNPs) using wet chemical reduction into the lamellar space layer of montmorillonite (MMT), and (iii) investigate the antibacterial potential of the AgNPs/MMT nanocomposite versus isolated strains of bacteria. Six bacterial species, including Escherichia coli , Salmonella spp., Pseudomonas aeruginosa , Staphylococcus aureus , Listeria monocytogenes , and Bacillus cereus were isolated from some food products (meat, fish, cheese, and vegetables). The Ag/MMT nanocomposite was synthesized and characterized using UV-visible spectroscopy, transmission electron microscopy, particle size analyzer, zeta potential, X-ray diffraction (XRD), and scanning electron microscopy with dispersive energy X-ray (EDX). The antibacterial effectiveness of the AgNPs/MMT nanocomposite further investigated distinct bacterial species using a zone of inhibition assay and microtiter-based methods. Nanoparticles with a narrow dimension range of 12 to 30 nm were identified using TEM analysis. The SEM was employed to view the sizeable flakes of the AgNPs/MMT. At 416 nm, the most excellent UV absorption was measured. Four silver metallic diffraction peaks were found in the XRD pattern during the study, and the EDX spectrum revealed a strong signal attributed to Ag nanocrystals. AgNPs/MMT figured out the powerful antibacterial action. The AgNPs/MMT nanocomposite confirmed outstanding minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against six isolates of foodborne pathogens, ranging from 15 to 75 µg/mL, respectively. The AgNPs/MMT's antibacterial potential against gram-negative bacteria was noticeably better than gram-positive bacteria. Therefore, the AgNPs/MMT nanocomposite has the potential to be used as a reliable deactivator in food processing and preservation to protect against foodborne pathogenic bacteria. This suggests that the nanocomposite may be effective at inhibiting the growth and proliferation of harmful bacteria in food, which could help to reduce the risk of foodborne illness.
- Published
- 2023
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7. Immobilization of Strontium Aluminate into Recycled Polycarbonate Plastics towards an Afterglow and Photochromic Smart Window.
- Author
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El-Hefnawy ME, Ismail AI, Alhayyani S, Al-Goul ST, Zayed MM, and Abou Taleb M
- Abstract
A transparent smart window made of recycled polycarbonate plastic (PCP) waste was prepared and immobilized with strontium aluminate phosphor nanoparticles (SAPN). It has afterglow emission, super-hydrophobicity, durability, photostability, good mechanical properties, ultraviolet protection, and high optical transmittance. To create an afterglow emission polycarbonate smart window (SAPN@PCP), recycled polycarbonate waste was integrated with various concentrations of SAPN (15-52 nm). SAP micro-scale powder was made using the solid-state high temperature method. The SAP nanoparticles were produced using the top-down method. To create a colorless plastic bulk, recycled polycarbonate waste was inserted into a hot bath. This colorless plastic was thoroughly combined with SAPN and cast to create an afterglow luminous smart window. To investigate its photoluminescence properties, spectrum profiles of excitation and emission were measured. According to the luminescence parameters, the phosphorescent colorless polycarbonate plates displayed a change in color to strong green under UV illumination and greenish-yellow in a dark box. The afterglow polycarbonate smart window displayed two emission peaks at 496 and 526 nm, and an absorption wavelength of 373 nm. Upon increasing the SAPN ratio, the hydrophobic activity, hardness, photostability, and UV protection were improved. Luminescent polycarbonate substrates with lower SAPN ratio demonstrated rapid and reversible fluorescence under UV light, while the higher SAPN content in the luminous polycarbonate substrates showed afterglow.
- Published
- 2022
- Full Text
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8. Fabrication and assessment of potent anticancer nanoconjugates from chitosan nanoparticles, curcumin, and eugenol.
- Author
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El-Sherbiny MM, Elekhtiar RS, El-Hefnawy ME, Mahrous H, Alhayyani S, Al-Goul ST, Orif MI, and Tayel AA
- Abstract
In cancer management and control, the most challenging difficulties are the complications resulting from customized therapies. The constitution of bioactive anticancer nanoconjugates from natural derivatives, e.g., chitosan (Ct), curcumin (Cur), and eugenol (Eug), was investigated for potential alternatives to cancer cells' treatment. Ct was extracted from Erugosquilla massavensis (mantis shrimp); then, Ct nanoparticles (NCt) was fabricated and loaded with Cur and/or Eug using crosslinking emulsion/ionic-gelation protocol and evaluated as anticancer composites against CaCo2 "colorectal adenocarcinoma" and MCF7 "breast adenocarcinoma" cells. Ct had 42.6 kDa molecular weight and 90.7% deacetylation percentage. The conjugation of fabricated molecules/composites and their interactions were validated via infrared analysis. The generated nanoparticles (NCt, NCt/Cur, NCt/Eug, and NCt/Cur/Eug composites) had mean particle size diameters of 268.5, 314.9, 296.4, and 364.7 nm, respectively; the entire nanoparticles carried positive charges nearby ≥30 mV. The scanning imaging of synthesized nanoconjugates (NCt/Cur, NCt/Eug, and NCt/Cur/Eug) emphasized their homogenous distributions and spherical shapes. The cytotoxic assessments of composited nanoconjugates using the MTT assay, toward CaCo2 and MCF7 cells, revealed elevated anti-proliferative and dose-dependent activities of all nanocomposites against treated cells. The combined nanocomposites (NCt/Eug/Cur) emphasized the highest activity against CaCo2 cells (IC
50 = 11.13 μg/ml), followed by Cur/Eug then NCt/Cur. The exposure of CaCo2 cells to the nanocomposites exhibited serious DNA damages and fragmentation in exposed cancerous cells using the comet assay; the NCt/Eug/Cur nanocomposite was the most forceful with 9.54 nm tail length and 77.94 tail moment. The anticancer effectuality of innovatively combined NCt/Cur/Eug nanocomposites is greatly recommended for such biosafe, natural, biocompatible, and powerful anticancer materials, especially for combating colorectal adenocarcinoma cells, with elevated applicability, efficiency, and biosafety., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 El-Sherbiny, Elekhtiar, El-Hefnawy, Mahrous, Alhayyani, Al-Goul, Orif and Tayel.)- Published
- 2022
- Full Text
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9. Fabrication of Nanofibers Based on Hydroxypropyl Starch/Polyurethane Loaded with the Biosynthesized Silver Nanoparticles for the Treatment of Pathogenic Microbes in Wounds.
- Author
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El-Hefnawy ME, Alhayyani S, El-Sherbiny MM, Sakran MI, and El-Newehy MH
- Abstract
Fabrication of electrospun nanofibers based on the blending of modified natural polymer, hydroxyl propyl starch (HPS) as one of the most renewable resources, with synthetic polymers, such as polyurethane (PU) is of great potential for biomedical applications. The as-prepared nanofibers were used as antimicrobial sheets via blending with biosynthesized silver nanoparticles (AgNPs), which were prepared in a safe way with low cost using the extract of Nerium oleander leaves, which acted as a reducing and stabilizing agent as well. The biosynthesized AgNPs were fully characterized by various techniques (UV-vis, TEM, DLS, zeta potential and XRD). The obtained results from UV-vis depicted that the AgNPs appeared at a wavelength equal to 404 nm affirming the preparation of AgNPs when compared with the wavelength of extract (there are no observable peaks). The average particle size of the fabricated AgNPs that mediated with HPS exhibited a very small size (less than 5 nm) with excellent stability (more than -30 mv). In addition, the fabricated nanofibers were also fully characterized and the obtained data proved that the diameter of nanofibers was enlarged with increasing the concentration of AgNPs. Additionally, the findings illustrated that the pore sizes of electrospun sheets were in the range of 75 to 350 nm. The obtained results proved that the presence of HPS displayed a vital role in decreasing the contact angle of PU nanofibers and thus, increased the hydrophilicity of the net nanofibers. It is worthy to mention that the prepared nanofibers incorporated with AgNPs exhibited incredible antimicrobial activity against pathogenic microbes that actually presented in human wounds. Moreover, P. aeruginosa was the most sensitive species to the fabricated nanofibers compared to other tested ones. The minimal inhibitory concentrations (MICs) values of AgNPs-3@NFs against P. aeruginosa , and E. faecalis , were 250 and 500 mg/L within 15 min, respectively.
- Published
- 2022
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10. Polyaspartate-Ionene/Na + -Montmorillonite Nanocomposites as Novel Adsorbent for Anionic Dye; Effect of Ionene Structure.
- Author
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El-Hamshary H, Elsherbiny AS, El-Newehy MH, and El-Hefnawy ME
- Abstract
Surface modification of sodium montmorillonite (Na
+ -Mt) was performed using antimicrobial agents to produce an ecofriendly nanocomposite. The adsorption performance of the nanocomposite has been evaluated for the removal of Acid Blue 25 dye (AB25) as a model organic pollutant from wastewater. Sodium montmorillonite (Na+ -Mt) was modified with three different ionene compounds through ion exchange, and further modified through reaction with polyaspartate to provide three ecofriendly nanocomposites (denoted ICP-1-3). The nanocomposites were characterized using FTIR, PXRD, TEM, SEM, and BET surface area. The adsorption isotherm of AB25 onto ICP-1, ICP-2 and ICP-3 was analyzed using the Langmuir, Freundlich, and Dubinin-Radushkevich (D-R) models. The adsorption isotherm was found to be best fitted by a Freundlich model. The thermodynamic parameters were calculated. The kinetics of the adsorption data were analyzed and the adsorption behavior was found to obey pseudo-second-order kinetics, and the intraparticle diffusion model. The adsorption mechanism was studied by FTIR.- Published
- 2020
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11. Synthesis and Application of New Amphiphilic Asphaltene Ionic Liquid Polymers to Demulsify Arabic Heavy Petroleum Crude Oil Emulsions.
- Author
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Ismail AI, Atta AM, El-Newehy M, and El-Hefnawy ME
- Abstract
Asphaltenes are heavy petroleum crude oil components which limit the production of petroleum crude oil due to their aggregation and their stabilization for all petroleum crude oil water emulsions. The present study aimed to modify the chemical structures of isolated asphaltenes by converting them into amphiphilic polymers containing ionic liquid moieties (PILs) to demulsify the emulsion and replace the asphaltene layers surrounding the oil or water droplets in petroleum crude oil emulsions. The literature survey indicated that no modification occurred to produce the PILs from the asphaltenes. In this respect, the asphaltenes were modified via oxidation of the lower aliphatic chain through carboxylation followed by conversion to asphaltene acid chloride that reacted with ethoxylated N-alkyl pyridinium derivatives. Moreover, the carboxylation of asphaltenes was carried out through the Diels-Alder reaction with maleic anhydride that was linked with ethoxylated N-alkyl pyridinium derivatives to produce amphiphilic asphaltene PILs. The produced PILs from asphaltenes acid chloride and maleic anhydride were designated as AIL and AIL-2. The chemical structure and thermal stability of the polymeric asphaltene ionic liquids were evaluated. The modified structure of asphaltenes AIL and AIL-2 exhibited different thermal characteristics involving glass transition temperatures (T
g ) at -68 °C and -45 °C, respectively. The new asphaltenes ionic liquids were adsorbed at the asphaltenes surfaces to demulsify the heavy petroleum crude emulsions. The demulsification data indicated that the mixing of AIL and AIL-2 100 at different ratios with ethoxylated N-alkyl pyridinium were demulsified with 100% of the water from different compositions of O:W emulsions 50:50, 90:10, and 10:90. The demulsification times for the 50:50, 90:10, and 10:90 O:W emulsions were 120, 120, and 60 min, respectively. The interaction of the PILs with asphaltene and mechanism of demulsification was also investigated.- Published
- 2020
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12. Bio-active maneonenes and isomaneonene from the red alga Laurencia obtusa.
- Author
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Bawakid NO, Alarif WM, Ismail AI, El-Hefnawy ME, Al-Footy KO, and Al-Lihaibi SS
- Subjects
- Anti-Inflammatory Agents, Non-Steroidal chemistry, Anti-Inflammatory Agents, Non-Steroidal isolation & purification, Apoptosis drug effects, Molecular Structure, Neutrophils drug effects, Nuclear Magnetic Resonance, Biomolecular, Sesquiterpenes chemistry, Anti-Inflammatory Agents, Non-Steroidal pharmacology, Laurencia chemistry, Sesquiterpenes isolation & purification, Sesquiterpenes pharmacology
- Abstract
Three previously undescribed compounds, maneonenes and isomaneonene derivatives; in addition to five known compounds, two cuparene, one chamigrene, and two cis-maneonenes were isolated from the Red Sea red alga Laurencia obtusa. The chemical structures of all unknown metabolites were characterized employing spectroscopic methods and then were further confirmed by single crystal X-ray analysis. Jeddahenyne A has C-5-C-12 etheric linkage and C-13-C-14 carbon-carbon double bond; Jeddahenyne B has in addition to the aforementioned etheric linkage a C-13 carbonyl function and absence of halogenation, unusual features for the maneonenes while 12-debromo-12-methoxy isomaneonene A shows unrecorded methoxylation at C-12. The apoptosis-inducing or inhibiting effect of both compounds on apoptosis of peripheral blood neutrophils was studied., (Copyright © 2017 Elsevier Ltd. All rights reserved.)
- Published
- 2017
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13. Extraction, purification, kinetic and thermodynamic properties of urease from germinating Pisum Sativum L. seeds.
- Author
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El-Hefnawy ME, Sakran M, Ismail AI, and Aboelfetoh EF
- Subjects
- Acrylic Resins, Chemical Precipitation, Chromatography, DEAE-Cellulose, Chromatography, Gel, Germination, Hydrolysis, Molecular Weight, Plant Extracts, Plant Proteins chemistry, Plant Proteins metabolism, Seeds, Thermodynamics, Urease chemistry, Urease metabolism, Biochemistry methods, Pisum sativum enzymology, Plant Proteins isolation & purification, Urea metabolism, Urease isolation & purification
- Abstract
Background: Urease, one of the highly efficient known enzymes, catalyzes the hydrolysis of urea into ammonia and carbon dioxide. The present study aimed to extract urease from pea seeds (Pisum Sativum L). The enzyme was then purified in three consequence steps: acetone precipitation, DEAE-cellulose ion-exchange chromatography, and gel filtration chromatography (Sephacryl S-200 column)., Results: The purification fold was 12.85 with a yield of 40%. The molecular weight of the isolated urease was estimated by chromatography to be 269,000 Daltons. Maximum urease activity (190 U/g) was achieved at the optimum conditions of 40°C and pH of 7.5 after 5 min of incubation. The kinetic parameters, Km and Vmax, were estimated by Lineweaver-Burk fits and found to be 500 mM and 333.3 U/g, respectively. The thermodynamic constants of activation, ΔH, Ea, and ΔS, were determined using Arrhenius plot and found to be 21.20 kJ/mol, 23.7 kJ/mol, and 1.18 kJ/mol/K, respectively., Conclusions: Urease was purified from germinating Pisum Sativum L. seeds. The purification fold, yield, and molecular weight were determined. The effects of pH, concentration of enzyme, temperature, concentration of substrate, and storage period on urease activity were examined. This may provide an insight on the various aspects of the property of the enzyme. The significance of extracting urease from different sources could play a good role in understanding the metabolism of urea in plants.
- Published
- 2014
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14. The effect of chloride and sulfate ions on the adsorption of Cd2+ on clay and sandy loam Egyptian soils.
- Author
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El-Hefnawy ME, Selim EM, Assaad FF, and Ismail AI
- Subjects
- Adsorption, Clay, Kinetics, Temperature, Aluminum Silicates chemistry, Cadmium chemistry, Chlorides chemistry, Ions, Silicon Dioxide chemistry, Soil chemistry, Sulfates chemistry
- Abstract
Adsorption of Cd(2+) on two types of Egyptian soils: clay (alluvial) and sandy loam (calcareous), was studied. Effect of changing the matrix electrolyte type and concentration was used to mimic the natural soil salts. Kinetics and thermodynamic parameters of the adsorption were calculated at two different electrolyte concentrations: 0.05 N and 0.15 N. The adsorption was described by Langmuir and Freundlich isotherms. Results showed that lower concentration of the NaCl or Na2SO4 electrolytes (0.05 N) had higher adsorption capacity. Also, the maximum adsorption of cadmium when using sulfate counter ion is about two to three times higher than that when using chloride (544 μg/g for alluvial soil and 170 μg/g for calcareous soil when using 0.05 N). Using NaCl as matrix electrolyte, Freundlich isotherms showed bi-linear fits that probably mean a two energy level adsorption. This might be explained by either the competition of Cd(2+) with Na(+) or its complexation with Cl(-).
- Published
- 2014
- Full Text
- View/download PDF
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