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This study presents a novel blend of synthesis techniques for shape-controlled ZnS nanoparticles. Zinc sulfide (ZnS) nanoparticles with distinct morphologies cauliflower-like microstructures (â¼4.5 µm) and uniform nanospheres (200-700 nm) were synthesized through an innovative blend of precipitation and hydrothermal techniques. Capping with polyvinylpyrrolidone (PVP) significantly decreased crystallite size (3.93 nm-2.36 nm), modulated the band gap (3.57 eV-3.71 eV), and dramatically influenced morphology, highlighting the novelty of shape-controlled synthesis and its impact on optoelectronic and functional properties. X-ray diffraction confirmed crystallinity and revealed the size-controlling influence of PVP. UV-vis spectroscopy suggested potential tuning of optical properties due to band gap widening upon PVP capping. Field-emission scanning electron microscopy (FESEM) unveiled distinct morphologies: cauliflower-like microstructures for ZnS and uniform nanospheres (200-700 nm) for PVP-ZnS. Both structures were composed of smaller spherical nanoparticles, demonstrating the role of PVP in promoting controlled growth and preventing agglomeration. High-resolution transmission electron microscope (HRTEM) images depicted that the majority of nanoparticles maintain a spherical shape, though slight deviations from perfect sphericity can be discerned. Fourier-transform infrared (FTIR) spectroscopy confirmed that successful PVP encapsulation is crucial for shaping nanospheres and minimizing aggregation through steric hindrance. Photocatalytic activity evaluation using methylene blue (MB) dye degradation revealed significantly faster degradation by PVP-ZnS under ultraviolet (UV) irradiation (within 60 min as compared to 120 min for ZnS), showcasing its superior performance. This improvement can be attributed to the smaller size, higher surface area, and potentially optimized band gap of PVP-ZnS. Additionally, PVP-ZnS exhibited promising antibacterial activity against S. aureus and P. aeruginosa, with increased activity at higher nanoparticle concentrations.
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Cadmium (Cd) contamination and soil salinity are the main environmental issues reducing crop productivity. This study aimed to examine the combined effects of salinity (NaCl) and Cd on the physiological and biochemical attributes of quinoa (Chenopodium quinoa Willd.). For this purpose, 30-day-old plants of quinoa genotype "Puno" were transplanted in Hoagland's nutrient solution containing diverse concentrations of Cd: 0, 50, 100, 200 µM Cd, and salinity: 0, 150, and 300 mM NaCl. Results demonstrated that plant growth, stomatal conductance, and pigment contents were significantly lower at all Cd concentrations than the control plants. Quinoa plants exhibited improved growth and tolerance against Cd when grown at a lower level of salinity (150 mM NaCl) combined with Cd. In contrast, the elevated concentration of salinity (300 mM NaCl) combined with Cd reduced shoot and root growth of experimental plants more than 50%. Combined application of salinity and Cd increased Na (25-fold), while lessened the Cd (twofold) and K (1.5-fold) uptake. A blend of high concentrations of Na and Cd caused overproduction of H2O2 (eightfold higher than control) contents and triggered lipid peroxidation. The activities of antioxidant enzymes: ascorbate peroxidase (APX), catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD) were 13, 12, 7 and ninefold higher than control to mitigate the oxidative stress. Due to restricted root to shoot translocation, and greater tolerance potential against Cd, the quinoa genotype, Puno, is suitable for phytostabilization of Cd in saline soils.
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Chenopodium quinoa , Chenopodium quinoa/genética , Cádmio/toxicidade , Cádmio/análise , Cloreto de Sódio/farmacologia , Salinidade , Biodegradação Ambiental , Peróxido de Hidrogênio , Estresse Oxidativo , Antioxidantes/metabolismo , SódioRESUMO
In this research work, focus has been made on a glassy carbon electrode (GCE) modified commercial micro and synthesized nano-CeO2 for the detection of hydrogen peroxide (H2O2). Firstly, CeO2 nanoleaves were prepared by solvothermal route. Both commercially available micro CeO2 and synthesized nano-CeO2 structures were analyzed by different characterization techniques. The Raman spectra of synthesized nano CeO2 has more oxygen vacancies than micro CeO2. SEM images revealed that the synthesized CeO2 acquired leaf-like morphology. The catalyst nano CeO2 offered mesoporosity from nitrogen adsorption-desorption isotherms with massive sites of activation for increasing efficiency. Experiments on determining H2O2 using micro CeO2 or nano-CeO2/GCE was conducted using cyclic voltammetry (CV) and amperometry. Enhanced H2O2 reduction peak current with lower potential was observed in nano-CeO2/GCE. The influence of scan rate and H2O2 concentration on the performance of nano-CeO2/GCE were also studied. The obtained results have indicated that nano-CeO2/GCE showed improved electrochemical sensing behavior towards the reduction of H2O2 than micro-CeO2/GCE and bare GCE. A linear relationship was obtained over 0.001 µM-0.125 µM concentration of H2O2, with good sensitivity 141.96 µA µM-1 and low detection limit of 0.4 nM. Hence, the present nano-CeO2 system will have a great potential with solvothermal synthesis approach in the development of electrochemical sensors.
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Peróxido de Hidrogênio , Nanoporos , Carbono/química , Técnicas Eletroquímicas/métodos , Eletrodos , Limite de DetecçãoRESUMO
This work investigates the electrochemical oxidation of palm oil mill effluent (POME) treatment using platinum (Pt) as anode and graphite as a cathode. The response surface methodology was used to investigate the relationships between different factors conditions (voltage, electrolysis time and chemical support) and responses of the treatment (chemical oxygen demand reduction, colour removal, and total oil removal). A quadratic mathematical model was chosen for all responses using Box-Behnken Design (BBD) with R2 0.9853 for COD reduction, R2 0.9478 for colour removal and R2 0.9185 for total oil removal. According to Derringer's function desirability, under the optimum condition (Voltage 15, electrolysis time 2 h, and 19.95 mg/L NaCl) of POME treatment, 84% of COD reduction, 98% of colour removal and 99% total oil of removal could be achieved. These results indicate that platinum as an anode material is effective for the electrochemical oxidation treatment of POME.
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Eliminação de Resíduos Líquidos , Poluentes Químicos da Água , Análise da Demanda Biológica de Oxigênio , Eletrodos , Resíduos Industriais/análise , Óleo de Palmeira , Platina , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análiseRESUMO
In the present investigation, green nano-zerovalent copper (GnZVCu), activated carbon (AC), chitosan (CS) and alginate (ALG) nanocomposites were produced and used for the elimination of chromium (VI) from a polluted solution. The nanocomposites GnZVCu/AC-CS-alginate and AC-CS-alginate were prepared. Analysis and characterization were performed by the following techniques: X-ray diffraction, energy dispersive X-ray spectroscopy, scanning electron microscopy, transmission electron microscopy and Fourier transform infrared spectroscopy. The SEM analysis revealed that the nanocomposites are extremely mesoporous, which leads to the greatest adsorption of Cr+6 (i.e., 97.5% and 95%) for GnZVCu/AC-CS-alginate and AC-CS-alginate, respectively. The adsorption efficiency was enhanced by coupling GnZVCu with AC-CS-alginate with a contact time of 40 min. The maximum elimination of Cr+6 with the two nanocomposites was achieved at pH 2. The isotherm model, Freundlich adsorption isotherm and kinetics model and P.S.O.R kinetic models were discovered to be better suited to describe the exclusion of Cr+6 by the nanocomposites. The results suggested that the synthesized nanocomposites are promising for the segregation of Cr+6 from polluted solutions, specially the GnZVCu/AC-CS-alginate nanocomposite.
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The anticancer activity of terretonin N (1) and butyrolactone I (2), obtained from the thermophilic fungus Aspergillus terreus TM8, was intensively studied against prostate adenocarcinoma (PC-3) and ovary adenocarcinoma (SKOV3) human cell lines. According to this study, both compounds showed potent cytotoxicity towards ovarian adenocarcinoma cells (SKOV3) with IC50 1.2 and 0.6 µg/mL, respectively. With respect to metastatic prostate cells (PC-3), the two compounds 1 and 2 showed a significantly promising cytotoxicity effect with IC50 of 7.4 and 4.5 µg/mL, respectively. The tested fungal metabolites showed higher rates of early and late apoptosis with little or no necrotic apoptotic pathway in all treated prostate adenocarcinoma (PC-3) and ovary adenocarcinoma (SKOV3) human cell lines, respectively. The results reported in this study confirmed the promising biological properties of terretonin N (1) and butyrolactone I (2) as anticancer agents via the induction of cellular apoptosis. However, further studies are needed to elucidate the molecular mechanism by which cellular apoptosis is induced in cancer cells.
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4-Butirolactona/análogos & derivados , Apoptose/efeitos dos fármacos , Aspergillus/química , Neoplasias Ovarianas/patologia , Neoplasias da Próstata/patologia , Terpenos/farmacologia , 4-Butirolactona/química , 4-Butirolactona/farmacologia , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Forma Celular/efeitos dos fármacos , Feminino , Humanos , Concentração Inibidora 50 , Masculino , Terpenos/químicaRESUMO
Nitroaromatic and nitroamine compounds such as 2,4,6-trinitrotoluene (TNT) are teratogenic, cytotoxic, and may cause cellular mutations in humans, animals, plants, and microorganisms. Microbial-based bioremediation technologies have been shown to offer several advantages against the cellular toxicity of nitro-organic compounds. Thus, the current study was designed to evaluate the ability of Trichoderma viride to degrade nitrogenous explosives, such as TNT, by microbiological assay and Gas chromatography-mass spectrometry (GC-MS) analysis. In this study, T. viride fungus was shown to have the ability to decompose, and TNT explosives were used at doses of 50 and 100 ppm on the respective growth media as a nitrogenous source needed for normal growth. The GC/MS analysis confirmed the biodegradable efficiency of TNT, whereas the initial retention peak of the TNT compounds disappeared, and another two peaks appeared at the retention times of 9.31 and 13.14 min. Mass spectrum analysis identified 5-(hydroxymethyl)-2-furancarboxaldehyde with the molecular formula C6H6O3 and a molecular weight of 126 g·mol-1 as the major compound, and 4-propyl benzaldehyde with a formula of C10H12O and a molecular weight of 148 g mol-1 as the minor compound, both resulting from the biodegradation of TNT by T. viride. In conclusion, T. viride could be used in microbial-based bioremediation technologies as a biological agent to eradicate the toxicity of the TNT explosive. In addition, future molecular-based studies should be conducted to clearly identify the enzymes and the corresponding genes that give T. viride the ability to degrade and remediate TNT explosives. This could help in the eradication of soils contaminated with explosives or other toxic biohazards.
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Substâncias Explosivas/química , Trichoderma/crescimento & desenvolvimento , Trinitrotolueno/química , Biodegradação Ambiental , Meios de Cultura/análise , Meios de Cultura/química , Cromatografia Gasosa-Espectrometria de Massas , Nitrogênio/química , Poluentes do Solo/química , Trichoderma/metabolismoRESUMO
Rational designing of metal-free carbon nitride based photocatalysts can lead to an excellent optical response and a higher photocatalytic activity driven by visible and solar light. This combines green photocatalytic technology with greener materials prepared by facile approaches for environmental remediation. Herein we report utilization of star photocatalyst g-C3N4 (CN) to form highly efficient hetero-assemblies along with acidified g-C3N4 (ACN), polyaniline (PANI), reduced graphene oxide (RGO) and biochar. By use of these organic semiconductors we synthesize g-C3N4/ACN/RGO@Biochar (GARB), g-C3N4/PANI/RGO@Biochar (GPRB) and ACN/PANI/RGO@Biochar (APRB) nano-assemblies with different optical response and band edge positions for a better charge flow and reduced recombination of carriers. These synthesized catalysts were used for visible light powered degradation of 2,4-Dichlorophenoxy acetic acid (2,4-D) and ibuprofen (IBN). APRB performs the best and degrades 99.7% and 98.4% of 2,4-D and IBN (20â¯mgâ¯L-1) under Xe lamp exposure in 50â¯min and retention of high activity in natural sunlight. Optical analysis, photoelectrochemical response and radical quenching studies show both hydroxyl and superoxide radical anions as major reactive species and a Z-scheme photocatalytic mechanism. RGO acts as an electron mediator and protects higher positioned bands of PANI and ACN in APRB for a remarkable photocatalytic activity for a metal free material. The degradation pathway was analyzed by LC-MS analysis and 42% and 40% total organic carbon was removed in 2â¯h for 2,4-D and IBN degradation respectively. The toxicity of degraded products was analyzed by analyzing viability of human peripheral blood cells with retaining of 99.1% cells.
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Águas Residuárias , Poluentes Químicos da Água , Ácido 2,4-Diclorofenoxiacético , Carvão Vegetal , Ibuprofeno , Nitrilas , FotóliseRESUMO
The contamination of water surfaces by mercury is a dangerous environmental problem due to its toxicity, which leads kidney damage. Activated carbon from mixed recyclable waste modified by phosphonium-based ionic liquid (IL-ACMRW) was therefore prepared and evaluated for Hg(II) remediation. The activated carbon used in this study was prepared from mixed waste, including cardboard, papers and palm wastes as cheap raw materials. The mixed Recyclable Waste Activated Carbon was combined with trihexyl(tetradecyl)phosphonium Bis2,4,4-(trimethylpentyl)phosphinate (Cyphos® IL 104) ionic liquid to form an adsorbent with organic-inorganic content, in order to improve the Hg(II) uptake from aqueous solutions. FTIR confirms the presence of P, C=O and OH after this modification. The adsorption process was investigated and the evaluated results showed that the capacity was 124 mg/g at pH 4, with a contact time of 90 min, an adsorbent dose of 0.4 g/L, and a Hg(II) concentration of 50 mg/L. This Hg(II) adsorption capacity is superior than that reported in the literature for modified multiwall carbon nanotubes. The adsorption of Hg(II) on the modified activated carbon from mixed recyclable waste was found to follow the pseudo second-order kinetics model. Isotherms of adsorption were analyzed via Freundlich and Langmuir models. The results indicated that Freundlich is the best model to describe the process, suggesting multilayer adsorption.
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Carvão Vegetal/química , Líquidos Iônicos/química , Mercúrio/química , Compostos Organofosforados/química , Adsorção , Poluentes Químicos da Água , Purificação da Água/métodosRESUMO
Herein, Cetyltrimethyl ammonium bromide (CTAB) intercalated and branched polyhydroxystyrene (BPS) functionalized montmorillonite (MMT) nano-composite (BPS-CTAB-MMT) was developed, characterized, and its potential as an adsorbent was tested in sequestering cationic dyes viz. rhodamine B (RB), crystal violet (CV), and methylene blue (MB) from aqueous environment. N2 adsorption/desorption isotherm showed mesoporous BPS-CTAB-MMT surface with a BET surface area of 273.8â¯m2/g. The appearance of sharp spikes at 2855 and 2925â¯cm-1 (associated with symmetric and asymmetric tensions of C - H bonds) in infra-red spectrum of BPS-CTAB-MMT indicates successful intercalation of MMT with CTAB and functionalization with BPS. The observed crystallite size of BPS-CTAB-MMT was 66â¯nm. Comparatively greater weight loss for BPS-CTAB-MMT (11%) than MMT (9%) was observed during thermogravimetric analysis. The adsorption of dyes on BPS-CTAB-MMT was pH dependent with maximum uptake was observed in the pH range: 5-6. For initial dyes concentration (Co) range: 50-150â¯mg/L, the observed equilibration time for CV was 300â¯min, whereas for RB and MB the equilibration time varied between 300 and 360â¯min. Modeling investigations revealed the applicability of Sips isotherm and pseudo-second-order (PSO) kinetic models to dyes adsorption data. Sips maximum adsorption capacity (qs) values for RB, CV, and MB at 55⯰C were 476.5, 438.7, and 432.7â¯mg/g, respectively. The adsorption of dyes on BPS-CTAB-MMT was thermodynamically favorable. Desorption studies showed 42.1% RB and 41.9% CV recovery with 0.1â¯M NaOH and CH3COCH3, respectively, while only traces of MB were recovered with tested eluents.
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Silicatos de Alumínio , Bentonita , Compostos de Cetrimônio , Adsorção , Cetrimônio , Argila , Corantes , CinéticaRESUMO
Antimicrobial peptides have gradually gained advantages over small molecule inhibitors for their multifunctional effects, synthesising accessibility and target specificity. The current study aims to determine an antimicrobial peptide to inhibit PknB, a serine/threonine protein kinase (STPK), by binding efficiently at the helically oriented hinge region. A library of 5626 antimicrobial peptides from publicly available repositories has been prepared and categorised based on the length. Molecular docking using ADCP helped to find the multiple conformations of the subjected peptides. For each peptide served as input the tool outputs 100 poses of the subjected peptide. To maintain an efficient binding for relatively a longer duration, only those peptides were chosen which were seen to bind constantly to the active site of the receptor protein over all the poses observed. Each peptide had different number of constituent amino acid residues; the peptides were classified based on the length into five groups. In each group the peptide length incremented upto four residues from the initial length form. Five peptides were selected for Molecular Dynamic simulation in Gromacs based on higher binding affinity. Post-dynamic analysis and the frame comparison inferred that neither the shorter nor the longer peptide but an intermediate length of 15 mer peptide bound well to the receptor. Residual substitution to the selected peptides was performed to enhance the targeted interaction. The new complexes considered were further analysed using the Elastic Network Model (ENM) for the functional site's intrinsic dynamic movement to estimate the new peptide's role. The study sheds light on prospects that besides the length of peptides, the combination of constituent residues equally plays a pivotal role in peptide-based inhibitor generation. The study envisages the challenges of fine-tuned peptide recovery and the scope of Machine Learning (ML) and Deep Learning (DL) algorithm development. As the study was primarily meant for generation of therapeutics for Tuberculosis (TB), the peptide proposed by this study demands meticulous invitro analysis prior to clinical applications.
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Peptídeos Antimicrobianos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Peptídeos Antimicrobianos/química , Peptídeos Antimicrobianos/farmacologia , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Mycobacterium tuberculosis/enzimologia , Mycobacterium tuberculosis/efeitos dos fármacos , Desenho de Fármacos , Proteínas de Bactérias/química , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/metabolismoRESUMO
The adsorption efficiency of cheap, ecofriendly, and easily available agro-waste, Trapa natans (Chestnut) and Citrullus lanatus (Watermelon) peels, has been investigated in their native forms (TNAT and CLAN) as well as citric acid impregnated forms (C-TNAT and C-CLAN), respectively, for the detoxification of toxic, deleterious, and carcinogenic Eosin yellow dye (EYD) from wastewater streams. Different operational parameters were optimized for the investigation of isothermal, kinetic and the thermodynamic models. R2 for sportive decontamination of Eosin by citric acid treated adsorbents were close to one, supporting the applicability of Langmuir, Temkin, and pseudo-second-order in this investigation. Maximum sorption capabilities were 222 and 667 mg/g for chemically treated bio-waste C-TNAT and C-CLAN, respectively, reflecting their efficient and promising performance, while Gibbs free energy revealed exothermic and spontaneous adsorption behavior. The kinetic statics for qe (cal) are quite close to qe (exp), indicating the viability and fitness of pseudo-second-order mechanisms. The present study suggests that both citric acid fabricated bio-waste C-TNAT and C-CLAN can be substantially employed to decontaminate persistent organic pollutants, like: Eosin yellow dye from wastewater using green approach to resolve socio-economic problems of developing countries.
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Ácido Cítrico , Amarelo de Eosina-(YS) , Lignina , Poluentes Químicos da Água , Purificação da Água , Ácido Cítrico/química , Amarelo de Eosina-(YS)/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Lignina/química , Adsorção , Purificação da Água/métodos , Cinética , Águas Residuárias/química , Termodinâmica , Biodegradação Ambiental , Concentração de Íons de HidrogênioRESUMO
Polymer monolithic stationary phases were prepared based on a cyclic anhydride as a reactive and tunable platform via ring-opening post-polymerization using primary amines, octadecylamine and benzylamine. The characterization techniques indicated the insertion of the functional groups into the original monoliths and confirmed the amidation reactions. The post-polymerization modification also improved the monolith's thermal and mechanical stability and induced significant improvement in their surface area. The stationary phases were synthesized inside small dimension stainless-steel columns (2.1 mm i.d. × 50 mm length). The prepared columns before and after modifications have been tested for the separation of the alkylbenzene series and some polycyclic aromatic hydrocarbons (PAHs) as model compounds. In all cases, the chromatographic performance in terms of the height equivalent to a theoretical plate on the functionalized monoliths was remarkably improved when compared with that on the unmodified monolith, which was between 9.59-39.49 µm and 4.08-31.50 µm using monoliths modified with octadecylamine and benzylamine, respectively. Under the same chromatographic conditions, the functionalization of monoliths with octadecylamine provided more hydrophobic interactions and enhanced the retention of alkylbenzenes, while the modification of monoliths with benzyl groups improved the separation and the retention of the PAHs through the strong π-π interactions. However, post-modification polymerization with octadecylamine and benzylamine enhanced the separation efficiency of the prepared columns toward all studied compounds. The repeatability of the injections on the same column and the reproducibility of the prepared columns have been studied for some selected parameters and estimated in terms of percent relative standard deviation (%RSD) for some of the studied compounds. The repeatability of the prepared columns was ≤9.42% (n = 5) based on run-to-run injections and ≤9.48% based on day-to-day injections for five successive days. The reproducibility levels, on the other hand, were ≤20.95% for all studied parameters in all cases. To assess their performance for the analysis of real samples, the applicability of the prepared columns was examined for the separation of the active ingredients extracted from some commercial pharmaceutical formulations and for the separation of tea water extract constituents. The validation data show the suitability of the columns for practical use in the routine analysis of these samples.
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Potentially toxic metal-polluted water resources are a heavily discussed topic the pollution by potentially toxic metals can cause significant health risks. Nanomaterials are actively developed towards providing high specific surface area and creating active adsorption sites for the treatment and remediation of these polluted waters. In an effort to tackle the limitations of conventional type adsorbents, nano-hydroxyapatite (HAp) was developed in this study by in situ generation onto wood powder, resulting in the formation of uniform hybrid powder (HAp@wood composite) structure consisting of HAp nanoparticles that showed the removal efficiency up to 80 % after 10 min; the maximum adsorption capacity for Cu(II) ions (98.95 mg/g-HAp) was higher compared to agglomerated nano-HAp (72.85 mg/g-HAp). The adsorption capacity of Cu(II) remained stable (89.85-107.66 mg/g-HAp) during the four adsorption-desorption cycles in multi-component system, thereby demonstrating high selectivity for Cu(II). This approach of using nanoparticle is relatively simple yet effective in improving the adsorption of potentially toxic metals and the developed approach can be used to develop advanced nanocomposites in commercial wastewater treatment.
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Aflatoxins AFB1, AFB2, AFG1, and AFG2 are toxic secondary metabolites produced by Aspergillus flavus and Aspergillus parasiticus and posses a potential threat to food safety. In the present work, liquid-liquid extraction and ultraperformance LC-MS/MS method has been applied for the determination of four naturally occurring aflatoxins AFB1, AFB2, AFG1, and AFG2 in nonalcoholic beer. Aflatoxins extraction from nonalcoholic beer was carried out using liquid-liquid extraction procedure. The effects of solvent-types were studied to obtain maximum recovery of the target analytes with minimum contamination. Among different solvents, the aflatoxins extraction was best achieved using ethyl acetate. The obtained recoveries were ranged from 85 to 96% with good quality parameters: LOD values between 0.001 and 0.003 ng/mL, linearity of the calibration curve (r(2) > 0.999), and repeatability (run-to-run) and reproducibility (day-to-day) precisions with RSDs lower than 5% (n = 5) achieved at 0.50 ng/mL concentration. The optimized liquid-liquid extraction in combination with ultraperformance LC-MS/MS was applied successfully to the analysis of AFB1, AFB2, AFG1, and AFG2 aflatoxins in 11 nonalcoholic beers and were detected up to 15.31 ng/L in some of the samples.
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Aflatoxinas/análise , Aflatoxinas/isolamento & purificação , Cerveja/análise , Cromatografia Líquida de Alta Pressão/métodos , Extração Líquido-Líquido/métodos , Espectrometria de Massas em Tandem/métodos , Contaminação de Alimentos/análise , Inocuidade dos AlimentosRESUMO
The present work describes the synthesis of a cellulose and gelatin based hydrogel by the grafting of poly(acrylic acid) using ammonium persulphate (APS)-glutaraldehyde as the initiator-crosslinker system. The structure of the hydrogel was studied through scanning electron microscopy (SEM) and FTIR. The maximum swelling rate of C-G-g-poly(AA) was found to be 92 g g-1 at pH 10. The size and structure of the prepared silver nanoparticles (AgNPs) were studied through TEM and zeta potential, and it was found that the synthesized AgNPs were spherical and the size range was 11-30 nm. The reduction process followed pseudo 1st order kinetics. EtBr and eosin dye degradation were more than 4 times faster, when AgNPs were used with sodium borohydride. Thus, it can be concluded that the synthesized C-G-g-poly(AA) AgNPs hybrid hydrogel is effective for the reduction and degradation of carcinogenic dyes in wastewater.
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The Fischer-Tropsch Synthesis (FTS) is a significant catalytic chemical reaction that produces ultra-clean fuels or chemicals with added value from a syngas mixture of CO and H2 obtained from biomass, coal, or natural gas. The presence of sulfur is not considered good for producing liquid fuels for(FTS). In this study, we reveal that the presence of sulfur in ferric sulfate Fe2(SO4)3 MOF provides the high amount, 52.50% of light hydrocarbons in the carbon chain distribution. The calcined ferric nitrate Fe(NO3)3 MOF reveals the highest 93.27% diesel production. Calcination is regarded as an essential factor in enhancing liquid fuel production. Here, we probed the calcination effect of Metal Organic Framework (MOF) on downstream application syngas to liquid fuels. The XRD results of MOF. N and P. MOF.N shows the formation of the active phase of iron carbide (Fe5C2), considered the most active phase of FTS. The scanning electron microscopy (SEM) images of iron sulfate MOF catalyst (P.MOF.S) reveals that the existence of sulfur creates pores inside the particles due to the reaction of free water molecules with the sulfur derivate. The surface functional groups of prepared MOFs and tested MOFS were analyzed by Fourier transforms infrared spectroscopy (FT-IR). The thermal stability of prepared MOFS was analyzed by Thermo gravimetric analysis (TGA). The surface areas and structural properties of the catalysts were measured by N2-Physiosorption technique.
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Biocompatible polymer-functionalized magnetic nanoparticles could offer promising applications in biomedical sciences. We fabricated polymer functionalized tri-manganese tetra oxide (Mn3O4) nanoparticles with the co-precipitation method and an octahedral crystal structure having a crystallite size of 10-17 nm was identified via XRD analyses. The SEM graph depicted the non-uniform and smooth surface of PEG-functionalized Mn3O4 NPs as compared to Mn3O4 and chitosan-coated Mn3O4 NPs. Elemental composition in the prepared sample was examined by EDX analysis. Various modes such as MnO, MnOH, OH, symmetric, and anti-symmetric of CH2 attached to the spectrum of Mn3O4 NPs were observed with FTIR analysis. The magnetization factor decreased and increase the coreacivity and retentivity of surface functionalized Mn3O4-NPs was calculated via VSM analysis. In-vitro bioassay, antibacterial activity was tested against Escherichiacoli, Bacillus cereus, and anti-fungal activities against two Fusarium strains indicated clear antimicrobial activities. The MTT assay to examine the anticancer activity against the MCF-7 cancer cell line was performed and the T1 MRI contrast agent demonstrated that PEG-coated Mn3O4 NPs exhibited anti-cancer activities. We propose that surface-functionalized magnetic NPs used for the treatment of cancer by using a remote controlled process of hyperthermia therapy.
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Anti-Infecciosos , Quitosana , Nanopartículas , Humanos , Polietilenoglicóis/química , Quitosana/farmacologia , Nanopartículas/química , Óxidos/farmacologia , Óxidos/química , Polímeros , Anti-Infecciosos/farmacologiaRESUMO
Indole-3-acetic acid (IAA) represents a crucial phytohormone regulating specific tropic responses in plants and functions as a chemical signal between plant hosts and their symbionts. The Actinobacteria strain of AW22 with high IAA production ability was isolated in Algeria for the first time and was characterized as Streptomyces rubrogriseus through chemotaxonomic analysis and 16 S rDNA sequence alignment. The suitable medium for a maximum IAA yield was engineered in vitro and in silico using machine learning-assisted modeling. The primary low-cost feedstocks comprised various concentrations of spent coffee grounds (SCGs) and carob bean grounds (CBGs) extracts. Further, we combined the Box-Behnken design from response surface methodology (BBD-RSM) with artificial neural networks (ANNs) coupled with the genetic algorithm (GA). The critical process parameters screened via Plackett-Burman design (PBD) served as BBD and ANN-GA inputs, with IAA yield as the output variable. Analysis of the putative IAA using thin-layer chromatography (TLC) and (HPLC) revealed Rf values equal to 0.69 and a retention time of 3.711 min, equivalent to the authentic IAA. AW 22 achieved a maximum IAA yield of 188.290 ± 0.38 µg/mL using the process parameters generated by the ANN-GA model, consisting of L-Trp, 0.6%; SCG, 30%; T°, 25.8 °C; and pH 9, after eight days of incubation. An R2 of 99.98%, adding to an MSE of 1.86 × 10-5 at 129 epochs, postulated higher reliability of ANN-GA-approach in predicting responses, compared with BBD-RSM modeling exhibiting an R2 of 76.28%. The validation experiments resulted in a 4.55-fold and 4.46-fold increase in IAA secretion, corresponding to ANN-GA and BBD-RSM models, respectively, confirming the validity of both models.
Assuntos
Fabaceae , Redes Neurais de Computação , Reprodutibilidade dos Testes , Ácidos Indolacéticos , Reguladores de Crescimento de Plantas , PlantasRESUMO
Today, dyes/pigment-based materials are confronting a serious issue in harming marine ecology. Annihilate these serious water pollutants using photoactive 2D nanohybrid catalysts showed promising comparativeness over available photocatalysts. In the present work, a facile route to decorate Ruthenium (Ru) on 2D MgB2 flower-like nanostructures was developed via ecofriendly guar gum biopolymer substantial template (MgB2/GG@Ru NFS) and its photocatalytic performance was reported. Synthesis of MgB2@Ru, MgB2/GG@Ru NFS and commercial MgB2, was studied by FTIR, XRD, FE-SEM, EDX, AFM, TEM, UV-vis spectra, and XPS analysis. From the results, the MgB2/GG@Ru NFS exhibited a superior photocatalytic performance (99.7 %) than its precursors MgB2@Ru (79.7 %), and MgB2 (53.7 %), with the degradation efficiency of the crystal violet (CV) within 100 min under visible light irradiation. The proposed photo-catalyst MgB2/GG@Ru NFS showed negligible loss of photocatalytic activity even after five successive cycles, revealing its reusability and enhanced stability due to the network structure. The photocatalytic mechanism for MgB2/GG@Ru NFS was evaluated by trapping experiment of active species, verifying that superoxide (O2-) and electron (e-) contributed significant role in the dye degradation.