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In our previous work, three different weight ratios of chitosan/PVA (1:3, 1:1, and 3:1) were blended and then cross-linked with trimellitic anhydride isothiocyanate (TAI) at a concentration depending on their chitosan content, obtaining three hydrogels symbolized by H13, H11, and H31. Pure chitosan was cross-linked with TAI, producing a hydrogel symbolized by H10. Further, three H31-based silver nanoparticles composites (H31/AgNPs1%, H31/AgNPs3%, and H31/AgNPs5%) were also synthesized. They were investigated, for the first time in this study, as adsorbents for Congo Red (CR) and Crystal Violet (CV) dyes. The removal efficiency of CR dye increased with increasing H10 content in the hydrogels, and with increasing AgNP content in the composites, reaching 99.91% for H31/AgNPs5%. For CV dye, the removal efficiency increased with the increase in the PVA content. Furthermore, the removal efficiency of CV dye increased with an increasing AgNP content, reaching 94.7% for H31/AgNPs5%. The adsorption capacity increased with the increase in both the initial dye concentration and temperature, while with an increasing pH it increased in the case of CV dye and decreased in the case of CR dye. The adsorption of CV dye demonstrated that the Freundlich isotherm model is better suited for the experimental results. Moreover, the results were best fitted with pseudo-second-order kinetic model.
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This paper explores the photochemical synthesis of noble metal nanoparticles, specifically gold (Au) and silver (Ag) nanoparticles, using a one-component photoinitiator system. The synthesis process involves visible light irradiation at a wavelength of 419 nm and an intensity of 250 mW/cm2. The radical-generating capabilities of the photoinitiators were evaluated using electron spin resonance (ESR) spectroscopy. The main objective of this study was to investigate how the concentration of metal salts influences the size and distribution of the nanoparticles. Proposed mechanisms for the photochemical formation of nanoparticles through photoinitiated radicals were validated using cyclic voltammetry. The results showed that the concentration of AgNO3 significantly impacted the size of silver nanoparticles, with diameters ranging from 1 to 5 nm at 1 wt% and 3 wt% concentrations, while increasing the concentration to 5 wt% led to an increase in the diameter of silver nanoparticles to 16 nm. When HAuCl4 was used instead of AgNO3, it was found that the average diameters of gold nanoparticles synthesized using both photoinitiators at different concentrations ranged between 1 and 4 nm. The findings suggest that variations in HAuCl4 concentration have minimal impact on the size of gold nanoparticles. The photoproduction of AuNPs was shown to be thermodynamically favorable, with the reduction of HAuCl4 to Au0 having ∆G values of approximately -3.51 and -2.96 eV for photoinitiators A and B, respectively. Furthermore, the photoreduction of Ag+1 to Ag0 was demonstrated to be thermodynamically feasible, with ∆G values of approximately -3.459 and -2.91 eV for photoinitiators A and B, respectively, confirming the effectiveness of the new photoinitiators on the production of nanoparticles. The synthesis of nanoparticles was monitored using UV-vis absorption spectroscopy, and their sizes were determined through particle size analysis of transmission electron microscopy (TEM) images.
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Nanopartículas Metálicas , Nanopartículas Metálicas/química , Ouro/química , Prata/química , Processos Fotoquímicos , Cloreto de Sódio , Cloreto de Sódio na Dieta , Tamanho da PartículaRESUMO
In this study, we developed highly efficient nonwoven membranes by modifying the surface of polypropylene (PP) and poly(butylene terephthalate) (PBT) through photo-grafting polymerization. The nonwoven membrane surfaces of PP and PBT were grafted with poly(ethylene glycol) diacrylate (PEGDA) in the presence of benzophenone (BP) and metal salt. We immobilized tertiary amine groups as BP synergists on commercial nonwoven membranes to improve PP and PBT surfaces. In situ Ag, Au, and Au/Ag nanoparticle formation enhances the nonwoven membrane surface. SEM, FTIR, and EDX were used to analyze the surface. We evaluated modified nonwoven membranes for photocatalytic activity by degrading methylene blue (MB) under LED and sunlight. Additionally, we also tested modified membranes for antibacterial activity against E. coli. The results indicated that the modified membranes exhibited superior efficiency in removing MB from water. The PBT showed the highest efficiency in dye removal, and bimetallic nanoparticles were more effective than monometallic. Modified membranes exposed to sunlight had higher efficiency than those exposed to LED light, with the PBT/Au/Ag membrane showing the highest dye removal at 97% within 90 min. The modified membranes showed reuse potential, with dye removal efficiency decreasing from 97% in the first cycle to 85% in the fifth cycle.
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Insecticides are important to increase crop yields, but their overuse has damaged the environment and endangered human health. In this study, residues of spiromesifen and spirodiclofen were determined in tomato fruit using a simple and efficient analytical procedure based on acetonitrile extraction, extract dilution, and UPLC-MS/MS. The linearity range was 1-100 µg/kg and 0.5-100 µg/kg, and the correlation coefficient (R2) and residuals were ≥0.9991 and ≤16.4%, respectively. The limit of determination (LOD) was 0.26 and 0.08 µg/kg, while the limit of quantification (LOQ) was verified at 5 µg/kg. The relative standard deviation of spiked replicates at 5 µg/kg analyzed in one day (RSDr, n = 6) was ≤8.35%, and within three different days (RSDR, n = 18) it was ≤15.85%, with recoveries exceeding 91.34%. The method recovery test showed a satisfactory value of 89.23-97.22% with an RSD of less than 12.88%. The matrix effect was determined after a 4-fold dilution of the raw extract and was -9.8% and -7.2%, respectively. The validated method was used to study the dissipation behavior of the tested analytes in tomato fruit under field conditions. First-order kinetics best described the dissipation rates. The calculated half-lives were 1.49-1.83 and 1.91-2.38 days for spiromesifen and spirodiclofen, respectively, after application of the authorized and doubled authorized doses, indicating that spiromesifen dissipated more rapidly than spirodiclofen. The final residue concentrations of spiromesifen and spirodiclofen were 0.307-0.751 mg/kg and 0.101-0.398 mg/kg, respectively, after two or three applications, and were below the European Union (EU) maximum residue limits. The chronic risk assessment indicates that both insecticides are safe for adult consumers.
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The copper II complex's novel benzimidazole Schiff base ligands were manufactured and gauged as a new photoredox catalyst/photoinitiator amalgamated with triethylamine (TEA) and iodonium salt (Iod) for the polymerization of ethylene glycol diacrylate while exposed to visible light by an LED Lamp at 405 nm with an intensity of 543 mW/cm2 at 28 °C. Gold and silver nanoparticles were obtained through the reactivity of the copper II complexes with amine/Iod salt. The size of NPs was around 1-30 nm. Lastly, the high performance of copper II complexes for photopolymerization containing nanoparticles is presented and examined. Ultimately, the photochemical mechanisms were observed using cyclic voltammetry. The preparation of the polymer nanocomposite nanoparticles in situ was photogenerated during the irradiation LED at 405 nm with an intensity of 543 mW/cm2 at 28 °C process. UV-Vis, FTIR, and TEM analyses were utilized for the determination of the generation of AuNPs and AgNPs which resided within the polymer matrix.
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Throughout this research, a unique optical sensor for detecting one of the most dangerous heavy metal ions, Cu(II), was designed and developed. The (4-mercaptophenyl) iminomethylphenyl naphthalenyl carbamate (MNC) sensor probe was effectively prepared. The Schiff base of the sensor shows a "turn-off" state with excellent sensitivity to Cu(II) ions. This innovative fluorescent chemosensor possesses distinctive optical features with a substantial Stocks shift (about 114 nm). In addition, MNC has remarkable selectivity for Cu(II) relative to other cations. Density functional theory (DFT) and the time-dependent DFT (TDDFT) theoretical calculations were performed to examine Cu(II) chelation structures and associated electronic properties in solution, and the results indicate that the luminescence quenching in this complex is due to ICT. Chelation-quenched fluorescence is responsible for the internal charge transfer (ICT)-based selectivity of the MNC sensing molecule for Cu(II) ions. In a 1:9 (v/v) DMSO-HEPES buffer (20 mM, pH = 7.4) solution, Fluorescence and UV-Vis absorption of the MNC probe and Cu(II) ions were investigated. By utilizing a solution containing several metal ions, the interference of other metal ions was studied. This MNC molecule has outstanding selectivity and sensitivity, as well as a low LOD (1.45 nM). Consequently, these distinctive properties enable it to find the copper metal ions across an actual narrow dynamic range (0-1.2 M Cu(II)). The reversibility of the sensor was obtained by employing an EDTA as a powerful chelating agent.
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Corantes Fluorescentes , Bases de Schiff , Espectrometria de Fluorescência , Bases de Schiff/química , Corantes Fluorescentes/química , Cobre/química , Metais , ÍonsRESUMO
A new hydrogel, based on chitosan crosslinked with 2-chlorophenyl-bis(6-amino-1,3-dimethyluracil-5-yl) methane, (2Clph-BU-Cs), has been successfully created. Various instrumental techniques such as elemental analysis, FTIR, SEM, and XRD were used to prove its structure. Its removal efficiency for anionic Congo red (CR) dye under different conditions for industrial wastewater treatment was studied. For optimizing the conditions to maximize CR dye removal, the impacts of temperature, contact time, pH, and initial concentration of the dye on adsorption capacity were investigated. The removal of the dye was pH-dependent, with a much higher value achieved at pH 4 than at pH 7 and 9. The maximum adsorption capacity of the hydrogel was 93.46 mg g-1. The model of adsorption process was fitted to the pseudo-second-order kinetic model. The intraparticle diffusion demonstrated the multi-step nature of the adsorption process. The thermodynamic results showed that the adsorption process was endothermic because of the positive value of enthalpy (43.70 kJ mol-1). The process of adsorption at high temperatures was spontaneous, according to the values of ∆G0. An increase in randomness was seen in the value of ∆S°. Generally, the investigated hydrogel has the potential to be used as a promising effective reusable adsorbent for industrial wastewater remediation.
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Coriandrum sativum is one of the most widespread curative plants in the world, being vastly cultivated in arid and semi-arid regions as one of the oldest spice plants. The present study explored the extraction of polysaccharides from Coriandrum sativum seeds and the evaluation of their antioxidant potential and hepatoprotective effects in vivo. The polysaccharide from coriander seeds was extracted, and the structural characterization was performed by FT-IR, UV-vis, DSC, NMR (1D and 2D), GC-MS, and SEC analysis. The polysaccharide extracted from Coriandrum sativum (CPS) seeds was characterized to evaluate its antioxidant and hepatoprotective capacities in rats. Results showed that CPS was composed of arabinose, rhamnose, xylose, mannose, fructose, galactose, and glucose in molar percentages of 6.2%, 3.6%, 8.8%, 17.7%, 5.2%, 32.9%, and 25.6%, respectively. Further, CPS significantly hindered cadmium-induced oxidation damage and exercised a protective effect against Cd hepatocytotoxicity, with a considerable reduction in MDA production and interesting CAT and SOD enzyme levels. Results suggest that CPS might be employed as a natural antioxidant source.
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A novel series of benzimidazole ureas 3a-h were elaborated using 2-(1H-benzoimidazol-2-yl) aniline 1 and the appropriate isocyanates 2a-h. The antioxidant and possible antidiabetic activities of the target benzimidazole-ureas 3a-h were evaluated. Almost all compounds 3a-h displayed strong to moderate antioxidant activities. When tested using the three antioxidant techniques, TAC, FRAP, and MCA, compounds 3b and 3c exhibited marked activity. The most active antioxidant compound in this family was compound 3g, which had excellent activity using four different methods: TAC, FRAP, DPPH-SA, and MCA. In vitro antidiabetic assays against α-amylase and α-glucosidase enzymes revealed that the majority of the compounds tested had good to moderate activity. The most favorable results were obtained with compounds 3c, 3e, and 3g, and analysis revealed that compounds 3c (IC50 = 18.65 ± 0.23 µM), 3e (IC50 = 20.7 ± 0.06 µM), and 3g (IC50 = 22.33 ± 0.12 µM) had good α-amylase inhibitory potential comparable to standard acarbose (IC50 = 14.21 ± 0.06 µM). Furthermore, the inhibitory effect of 3c (IC50 = 17.47 ± 0.03 µM), 3e (IC50 = 21.97 ± 0.19 µM), and 3g (IC50 = 23.01 ± 0.12 µM) on α-glucosidase was also comparable to acarbose (IC50 = 15.41 ± 0.32 µM). According to in silico molecular docking studies, compounds 3a-h had considerable affinity for the active sites of human lysosomal acid α-glucosidase (HLAG) and pancreatic α-amylase (HPA), indicating that the majority of the examined compounds had potential anti-hyperglycemic action.
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A new series of hydrogels was successfully prepared by incorporating various substituted bisuracil (R-BU) linkages between chitosan Schiff's base chains (R-BU-CsSB) and between chitosan chains (R-BU-Cs). After protection of the amino groups of chitosan by benzaldehyde, yielding chitosan Schiff's base (CsSB), the reaction with epichlorohydrin was confined on the -OH on C6 to produce epoxy chitosan Schiff's base (ECsSB), which was reacted with R-BU to form R-BU-CsSB hydrogels, and finally, the bioactive amino groups of chitosan were restored to obtain R-BU-Cs hydrogels. Further, some R-BU-Cs-based ZnO nanoparticle (R-BU-Cs/ZnONPs) composites were also prepared. Appropriate techniques such as elemental analysis, FTIR, XRD, SEM, and EDX were used to verify their structures. Their inhibition potency against all the tested microbes were arranged as: ZnONPs bio-composites > R-BU-Cs hydrogels > R-BU-CsSB hydrogels > Cs. Their inhibition performance against Gram-positive bacteria was better than Gram-negative ones. Their minimum inhibitory concentration (MIC) values decreased as a function of the negative resonance effect of the substituents in the aryl ring of R-BU linkages in the hydrogels. Compared with Vancomycin, the ZnONPs bio-composites showed superior inhibitory effects against most of the tested Gram-negative bacteria, all inspected Gram-positive ones, and all investigated fungi.
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The removal of dyes from textile effluents utilizing advanced wastewater treatment methods with high efficiency and low cost has received substantial attention due to the rise in pollutants in water. The purpose of this work is to give a comprehensive analysis of the different treatments for removing chemical dyes from textile effluents. The capability and potential of conventional treatments for the degradation of dyeing compounds in aqueous media, as well as the influence of multiple parameters, such as the pH solution, initial dye concentration, and adsorbent dose, are presented in this study. This study is an overview of the scientific research literature on this topic, including nanoreductive and nanophotocatalyst processes, as well as nanoadsorbents and nanomembranes. For the purpose of treating sewage, the special properties of nanoparticles are currently being carefully researched. The ability of nanomaterials to remove organic matter, fungus, and viruses from wastewater is another benefit. Nanomaterials are employed in advanced oxidation techniques to clean wastewater. Additionally, because of their small dimensions, nanoparticles have a wide effective area of contact. Due to this, nanoparticles' adsorption and reactivity are powerful. The improvement of nanomaterial technology will be beneficial for the treatment of wastewater. This report also offers a thorough review of the distinctive properties of nanomaterials used in wastewater treatment, as well as their appropriate application and future possibilities. Since only a few types of nanomaterials have been produced, it is also important to focus on their technological feasibility in addition to their economic feasibility. According to this study, nanoparticles (NPs) have a significant adsorption area, efficient chemical reactions, and electrical conductivity that help treat wastewater effectively.
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Composite coatings of polyvinylidene fluoride (PVDF)/CeO2 were developed by using the spray approach to explore the wetting and corrosion behaviour of coated materials for applications related to industry. PVDF was combined with different quantities of CeO2 nanoparticles followed by spraying onto glass, aluminium, and steel substrates. The sessile droplet method and microscopy studies were used to assess the wetting behaviour and morphology of the coated surfaces, respectively. The corrosion resistance of uncoated substrates coated with PVDF only was compared with those coated with PVDF/CeO2 nanoparticles through Tafel polarization techniques. In psi, the force of adhesion was measured between the coating layer and the substrates. The PVDF/CeO2-coated steel had a significantly greater water contact angle and lower contact angle hysteresis than coated aluminium and glass substrates, reaching 157 ± 2° and 8 ± 1°, respectively. The corrosion protection efficiency of the superhydrophobic PVDF/CeO2 coatings was considerably higher for steel and aluminium when compared with PVDF coatings. The PVDF/CeO2 coated substrates had modest adhesion between the coating layer and the substrates, but it was still acceptable. Furthermore, the PVDF/CeO2 coatings outperformed PVDF alone in terms of mechanical properties.
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We developed a new optical sensor for tracing Hg(II) ions. The detection affinity examines within a concentration range of 0-4.0 µM Hg(II). The sensor film is based on Methyl 2-hydroxy-3-(((2S,2'R,3a'S,5R)-2-isopropyl-5,5'-dimethyl-4'-oxotetrahydro-2'H-spiro[cy-clohexane-1,6'-im-idazo[1,5-b]isoxazol]-2'-yl)methyl)-5-methylbenzoate (IXZD). The novel synthesized compound could be utilized as an optical turn-on chemosensor for pH. The emission intensity is highly enhanced for the deprotonated form concerning the protonated form. IXZD probe has a characteristic fluorescence peak at 481 nm under excitation of 351 nm with large Stocks shift of approximately 130 nm. In addition, the binding process of IXZD:Hg(II) presents a 1:1 molar ratio which is proved by the large quench of the 481 nm emission peak of IXZD and the growth of a new emission peak at 399 nm (blue shift). The binding configurations with one Hg(II) cation and its electronic characteristics were investigated by applying the Density Functional Theory (DFT) and the time-dependent DFT (TDDFT) calculations. Density functional theory (DFT) and the time-dependent DFT (TDDFT) theoretical results were provided to examine Hg(II)-IXZD structures and their electronic properties in solution. The developed chemical sensor was offered based on the intramolecular charge transfer (ICT) mechanism. The sensor film has a significantly low limit of detection (LOD) for Hg(II) of 0.025 µM in pH 7.4, with a relative standard deviation RSDr (1%, n = 3). Lastly, the IXZD shows effective binding affinity to mercury ions, and the binding constant Kb was estimated to be 5.80 × 105 M-1. Hence, this developed optical sensor film has a significant efficiency for tracing mercury ions based on IXZD molecule-doped sensor film.
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Mercúrio , Mercúrio/química , Íons , Limite de Detecção , Espectrometria de Fluorescência , Concentração de Íons de HidrogênioRESUMO
Allium roseum is one of the medicinal plants of the Liliaceae family, widely used in the food industry and traditional medicine. It is known for its various biological properties, such as its antioxidant, antiviral, antidiabetic, and anti-inflammatory activities. The present work aims to extract the polysaccharides from Allium roseum leaves and evaluate their antioxidant activities and hepatoprotective effects in vivo. Three polysaccharides from the leaves of Allium roseum were sequentially extracted in three media: water, chelating, and basic, respectively. They were characterized by size exclusion chromatography, gas chromatography mass spectrometry, FTIR-ATR, and NMR spectroscopy (1D and 2D). The different polysaccharides principally consist of glucose, galactose, mannose, rhamnose, xylose, and galacturonic acid. The antioxidant activity and hepatoprotective effect of the extracts against Cd-caused oxidative stress in liver mouse were tested. Cd treatment, during 24 h, enhanced significantly lipid peroxidation by a high production of malondyaldehyd (MDA) and superoxide dismutase (SOD) activity. In contrast, catalase activity (CAT) was decreased after the same period of exposure to the metal. The polysaccharides pre-treatment improved the antioxidant defense system to a great degree, mainly explained by the modulating levels of oxydative stress biomarkers (MDA, SOD, and CAT). This research clearly shows that Allium roseum polysaccharides, especially those extracted in aqueous medium, can be used as natural antioxidants with hepatoprotective properties.
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Currently, particular attention is paid to public health related to the field of γ-ray dosimetry, which is becoming increasingly important in medical diagnostic processes. Incorporating sensitive dyes as radiation dose sensors in different material hosts has shown promising radiation dosimetry application routes. In this perspective, the current study proposes a new fluorescent dye based on boron difluoride complex, the pyridomethene-BF2 named 2-(1-(difluoroboraneyl)-1,2-dihydroquinolin-2-yl)-2-(1-methylquinoxalin-2-ylidene) acetonitrile (DBDMA) as an indicator for low γ-ray doses. The different optical and quantum chemical parameters and the spectral behavior of the selected fluorescent dye were first studied. Then, PVP/DBDMA electrospun nanofibers and PVA/DBDMA thin films were prepared. The different UV-vis spectrophotometric and fluorescence studies revealed a clear change after exposure to different γ-ray doses. Thermogravimetric analysis exhibited excellent thermal stability of the prepared nanocomposite films, showing altered thermal behavior after γ-ray treatment. Furthermore, the SEM evaluation displayed a significant modification in the surface morphology of the two designed nanomaterials with increased radiation dose intensity. These novel forms of dosimeter designed in nanoscale composites could therefore constitute a promising and efficient alternative for rapid and accurate detection of low doses of γ-rays in various medical applications.
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New 1,3,4-thiadiazole thioglycosides linked to a substituted arylidine system were synthesized via heterocyclization via click 1,3-dipolar cycloaddition. The click strategy was used for the synthesis of new 1,3,4-thiadiazole and 1,2,3-triazole hybrid glycoside-based indolyl systems as novel hybrid molecules by reacting azide derivatives with the corresponding acetylated glycosyl terminal acetylenes. The cytotoxic activities of the compounds were studied against HCT-116 (human colorectal carcinoma) and MCF-7 (human breast adenocarcinoma) cell lines using the MTT assay. The results showed that the key thiadiazolethione compounds, the triazole glycosides linked to p-methoxyarylidine derivatives and the free hydroxyl glycoside had potent activity comparable to the reference drug, doxorubicin, against MCF-7 human cancer cells. Docking simulation studies were performed to check the binding patterns of the synthesized compounds. Enzyme inhibition assay studies were also conducted for the epidermal growth factor receptor (EGFR), and the results explained the activity of a number of derivatives.
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Antineoplásicos , Tioglicosídeos , Humanos , Simulação de Acoplamento Molecular , Triazóis/química , Glicosídeos/farmacologia , Azidas/farmacologia , Relação Estrutura-Atividade , Proliferação de Células , Tioglicosídeos/química , Antineoplásicos/química , Receptores ErbB/metabolismo , Células MCF-7 , Doxorrubicina/farmacologia , Alcinos/farmacologia , Estrutura Molecular , Ensaios de Seleção de Medicamentos AntitumoraisRESUMO
Toxicity and resistance to newly synthesized anticancer drugs represent a challenging phenomenon of intensified concern arising from variation in drug targets and consequently the prevalence of the latter concern requires further research. The current research reports the design, synthesis, and anticancer activity of new 1,2,3-triazole-coumarin-glycosyl hybrids and their 1,2,4-triazole thioglycosides as well as acyclic analogs. The cytotoxic activity of the synthesized products was studied against a panel of human cancer cell lines. Compounds 8, 10, 16 and 21 resulted in higher activities against different human cancer cells. The impact of the hybrid derivative 10 upon different apoptotic protein markers, including cytochrome c, Bcl-2, Bax, and caspase-7 along with its effect on the cell cycle was investigated. It revealed a mitochondria-apoptotic effect on MCF-7 cells and had the ability to upregulate pro-apoptotic Bax protein and downregulate anti-apoptotic Bcl-2 protein and thus implies the apoptotic fate of the cells. Furthermore, the inhibitory activities against EGFR, VEGFR-2 and CDK-2/cyclin A2 kinases for 8, 10 and 21 were studied to detect the mechanism of their high potency. The coumarin-triazole-glycosyl hybrids 8 and 10 illustrated excellent broad inhibitory activity (IC50= 0.22 ± 0.01, 0.93 ± 0.42 and 0.24 ± 0.20 µM, respectively, for compound 8), (IC50 = 0.12 ± 0.50, 0.79 ± 0.14 and 0.15± 0. 60 µM, respectively, for compound 10), in comparison with the reference drugs, erlotinib, sorafenib and roscovitine (IC50 = 0.18 ± 0.05, 1.58 ± 0.11 and 0.46 ± 0.30 µM, respectively). In addition, the docking study was simulated to afford better rationalization and put insight into the binding affinity between the promising derivatives and their targeted enzymes and that might be used as an optimum lead for further modification in the anticancer field.
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Antineoplásicos , Tioglicosídeos , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células , Cumarínicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Glicosídeos/farmacologia , Humanos , Mitocôndrias/metabolismo , Simulação de Acoplamento Molecular , Estrutura Molecular , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Relação Estrutura-Atividade , Tioglicosídeos/farmacologia , Triazóis/químicaRESUMO
Dates are very rich in various nutritious compounds, especially reducing sugars. Sugars ensure both anaerobic and aerobic fermentation, carried out respectively for the production of bioethanol and vinegar. Currently, the world production of dates is constantly increasing owing to the significant improvement in production conditions following the continuous scientific and technological development of this field. The Kingdom of Saudi Arabia is one of the most important world producers of dates, occupying the second place by producing 17% of the total world production. This is why it has become a national priority to find new ways to exploit and further valorize dates and palm waste in the development of new and sustainable products. The present study was designed to explore the possible study of a variety of date palm by-products in the production of bioethanol and vinegar via Saccharomyces cerevisiae. Different parameters of bioethanol and vinegar production, including pH, time, fermentation temperature, and yeast concentration, were studied and optimized. Chemical, physicochemical, purity behavior, and antioxidant performance were carried out via NMR, FTIR, and antioxidant activity essays (TPC, DPPH, FRAP, and ß-carotene bleaching test) with the aim to evaluate the potential of the bioethanol and vinegar samples extracted from date palm by-products. Khalas date vinegar revealed significantly more phenolic content (5.81 mg GAE/mL) (p < 0.05) than the different kinds of vinegar tested (Deglet Nour and Black dates; 2.3 and 1.67 mg GAE/mL, respectively) and the commercial vinegar (1.12 mg GAE/mL). The Khalas date vinegar generally showed a higher carotenoid value and better antioxidant activity than the other vinegars extracted from other date varieties and commercially available vinegar. The results confirmed the high quality of the bioethanol and vinegar products, and the efficiency of the developed production processes.
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This study represents the design and synthesis of a new set of triazole-coumarin-glycosyl hybrids and their tetrazole hybrid analogues possessing various sugar moieties and modified analogues. All the newly synthesized derivatives were screened for their cytotoxic activities against a panel of human cancer cell lines. The coumarin derivatives 10, 13 and 15 derivatives revealed potent cytotoxic activities against Paca-2, Mel-501, PC-3 and A-375 cancer cell lines. These promising analogues were further examined for their inhibitory assessment against EGFR, VEGFR-2 and CDK-2/cyclin A2 kinases. The coumarin-tetrazole 10 displayed broad superior inhibitory activity against all screened enzymes compared with the reference drugs, erlotinib, sorafenib and roscovitine, respectively. The impact of coumarin-tetrazole 10 upon cell cycle and apoptosis induction was determined to detect its mechanism of action. Additionally, it upregulated the levels of casp-3, casp-7 and cytochrome-c proteins and downregulated the PD-1 level. Finally, molecular docking study was simulated to afford better rationalization and gain insight into the binding affinity between the promising derivatives and their targeted enzymes, which could be used as an optimum lead for further modification in the anticancer field.
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Antineoplásicos , Receptor 2 de Fatores de Crescimento do Endotélio Vascular , Antineoplásicos/química , Proliferação de Células , Cumarínicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Receptores ErbB/metabolismo , Glicosídeos/química , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-Atividade , Triazóis/químicaRESUMO
Novel hydrogels were prepared by blending chitosan and poly(vinyl alcohol), PVA, then crosslinking the resulting blends using trimellitic anhydride isothiocyanate at a concentration based on chitosan content in the blends. The weight ratios of chitosan: PVA in the blends were 1:3, 1:1, and 3:1 to produce three hydrogels symbolized as H13, H11, and H31, respectively. For a comparison, H10 was also prepared by crosslinking pure chitosan with trimellitic anhydride isothiocyanate. For further modification, three H31/silver nanocomposites (AgNPs) were synthesized using three different concentrations of silver nitrate to obtain H31/AgNPs1%, H31/AgNPs3% and H31/AgNPs5%. The structures of the prepared samples were emphasized using various analytical techniques. PVA has no inhibition activity against the tested microbes and biofilms. The antimicrobial and anti-biofilm formation activities of the investigated samples was arranged as: H31/AgNPs5% ≥ H31/AgNPs3% > H31/AgNPs1% > H10 > H31 > H11 > H13 > chitosan. H31/AgNPs5% and H31/AgNPs3% were more potent than Vancomycin and Amphotericin B against most of the tested microbes. Interestingly, H31 and H31/AgNPs3% were safe on the normal human cells. Consequently, hydrogels resulting from crosslinked blends of chitosan and PVA loaded with AgNPs in the same structure have significantly reinforced the antimicrobial and inhibition activity against the biofilms of PVA.