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1.
Int J Biol Macromol ; 267(Pt 1): 131432, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38583849

RESUMO

The potential applications of cellulose nanofibril-based foam materials can be expanded by their enhanced water durability. This study proposes two crosslinking methods to improve the water durability of the oven-dried carboxymethylated cellulose nanofibril (CMCNF) foam. The first method involves the addition of a crosslinker, polyamideamine epichlorohydrin. The second method is the self-crosslinking of CMCNFs via heat treatment at 140 °C for less than an hour, which is a simple way to crosslink CMCNF-based materials. Both crosslinking methods resulted in excellent water durability and wet resilience of the foams, which also exhibited high water absorbency. Furthermore, neither method affected the structural nor mechanical properties of the oven-dried CMCNF foams. In particular, self-crosslinking by heat treatment proved to be as effective as using a crosslinking agent. Compared to the freeze-dried foam, the oven-dried foam exhibited slower methylene blue (MB) dye adsorption but a higher maximum adsorption capacity (238-250 mg/g), attributed to the closed pore structure and a larger specific surface area. In addition, the isotherm and reusability of the foam for MB adsorption were investigated. These crosslinking processes expanded the potential use of oven-dried CMCNF foams as adsorbents for cationic dyes.


Assuntos
Celulose , Corantes , Reagentes de Ligações Cruzadas , Azul de Metileno , Nanofibras , Água , Nanofibras/química , Adsorção , Água/química , Celulose/química , Celulose/análogos & derivados , Corantes/química , Azul de Metileno/química , Reagentes de Ligações Cruzadas/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Epicloroidrina/química
2.
Chemosphere ; 357: 141970, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38608776

RESUMO

The extraction of non-steroidal anti-inflammatory drugs (NSAIDs) from water bodies is imperative due to the potential harm to humans and the ecosystem caused by NSAID-contaminated water. Quaternary amino-functionalized epichlorohydrin cross-linked chitosan fibers (QECFs), an economical and eco-friendly adsorbent, were successfully prepared using a simple and gentle method for efficient diclofenac (DCF) adsorption. Additionally, the optimized factors for the preparation of QECFs included epichlorohydrin concentration, pH, temperature, and (3-chloro-2-hydroxypropyl) trimethylammonium chloride (CHTAC) concentration. QECFs demonstrated excellent adsorption performance for DCF across a broad pH range of 7-12. The calculated maximum adsorption capacity and the amount of adsorbed DCF per adsorption site were determined to be 987.5 ± 20.1 mg/g and 1.2 ± 0.2, respectively, according to the D-R and Hill isotherm models, at pH 7 within 180 min. This performance surpassed that of previously reported adsorbents. The regeneration of QECFs could be achieved using a 0.5 mol/L NaOH solution within 90 min, with QECFs retaining their original fiber form and experiencing only a 9.18% reduction in adsorption capacity after 5 cycles. The Fourier transform infrared spectrometer and X-ray photoelectron spectroscopy were used to study the characterization of QECFs, the preparation mechanism of QECFs, and the adsorption mechanism of DCF by QECFs. Quaternary ammonium groups (R4N+) were well developed in QECFs through the reaction between amino/hydroxyl groups on chitosan and CHTAC, and approximately 0.98 CHTAC molecule with 0.98 R4N+ group were immobilized on each chitosan monomer. Additionally, these R4N+ on QECFs played a crucial role in the removal of DCF.


Assuntos
Anti-Inflamatórios não Esteroides , Quitosana , Diclofenaco , Águas Residuárias , Poluentes Químicos da Água , Quitosana/química , Diclofenaco/química , Adsorção , Poluentes Químicos da Água/química , Águas Residuárias/química , Concentração de Íons de Hidrogênio , Anti-Inflamatórios não Esteroides/química , Purificação da Água/métodos , Eliminação de Resíduos Líquidos/métodos , Temperatura , Epicloroidrina/química
3.
Environ Monit Assess ; 196(4): 332, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38429461

RESUMO

Machine learning was used to provide data for further evaluation of potential extraction of octathiocane (S8), a commercially useful by-product, from Acid Mine Drainage (AMD) by predicting sulphate levels in an AMD water quality dataset. Individual ML regressor models, namely: Linear Regression (LR), Least Absolute Shrinkage and Selection Operator (LASSO), Ridge (RD), Elastic Net (EN), K-Nearest Neighbours (KNN), Support Vector Regression (SVR), Decision Tree (DT), Extreme Gradient Boosting (XGBoost), Random Forest (RF), Multi-Layer Perceptron Artificial Neural Network (MLP) and Stacking Ensemble (SE-ML) combinations of these models were successfully used to predict sulphate levels. A SE-ML regressor trained on untreated AMD which stacked seven of the best-performing individual models and fed them to a LR meta-learner model was found to be the best-performing model with a Mean Squared Error (MSE) of 0.000011, Mean Absolute Error (MAE) of 0.002617 and R2 of 0.9997. Temperature (°C), Total Dissolved Solids (mg/L) and, importantly, iron (mg/L) were highly correlated to sulphate (mg/L) with iron showing a strong positive linear correlation that indicated dissolved products from pyrite oxidation. Ensemble learning (bagging, boosting and stacking) outperformed individual methods due to their combined predictive accuracies. Surprisingly, when comparing SE-ML that combined all models with SE-ML that combined only the best-performing models, there was only a slight difference in model accuracies which indicated that including bad-performing models in the stack had no adverse effect on its predictive performance.


Assuntos
Monitoramento Ambiental , Epicloroidrina , Ferro , Aprendizado de Máquina , Sulfatos
4.
Food Chem ; 445: 138772, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38394908

RESUMO

The fabrication of coated papers using hydrophilic and biodegradable polymers is important for developing sustainable packaging materials with high barrier and superior mechanical properties. However, water, which is used as the solvent in the paper coating process using hydrophilic polymers, deforms the shape of the paper and deteriorates performance. Therefore, we propose a new coating process that treats Kraft paper (KP) with epichlorohydrin (ECH) as a binder before the coating process. Crosslinked polyvinyl alcohol is coated on the ECH-treated KP using a solution casting method. ECH maintains the shape of the paper and improves coating uniformity; significantly enhances interfacial interactions, which increases barrier properties and sealing strength; and extends the shelf life of biscuits by reducing oxygen and moisture permeability. An ecotoxicity test using Lolium multiflorum demonstrates an insignificant phytotoxicity level for the as-prepared coated papers. Thus, ECH-treated KP is a potential candidate for high-barrier food packaging.


Assuntos
Epicloroidrina , Água , Embalagem de Alimentos , Polímeros , Solventes
5.
Chemosphere ; 352: 141321, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38307339

RESUMO

This work presents the synthesis of Pd-loaded microporous titanosilicalite-1 (Pd/TS-1) and Pd-loaded hierarchical titanosilicalite-1 (Pd/HTS-1) with abundant mesopores (2-30 nm) inside the framework via hydrothermal method using polydiallydimethyl ammonium chloride as the non-surfactant mesopore template. XRD, N2 sorption, FT-IR, FESEM-EDX, TEM, XPS, and DR-UV techniques were used to characterize the morphological and physicochemical properties of the synthesized materials. These materials were tested as heterogeneous catalysts, along with tetrapropylammonium bromide as co-catalyst, for cycloaddition reactions of CO2 with epoxides to produce cyclic carbonates. It was found that the epoxide conversions were influenced by acidity and pore accessibility of the catalysts. Using Pd/HTS-1 facilitated bulky substrates to access active sites, resulting in higher conversions than Pd/TS-1. Over 85 % conversions were achieved for at least five consecutive cycles without significant loss in catalytic activity. The interaction between the Pd active surfaces and epichlorohydrin (ECH) was further studied by DFT calculations. The existence of Pd(200) was more influential on adsorbing epichlorohydrin (ECH) and subsequent formation of dissociated ECH (DECH) intermediate than Pd(111) surface. However, Pd(111) was dominant in enhancing the activity of DECH species for capturing CO2. Therefore, the co-existence of Pd(200) and Pd(111) surfaces was needed for cycloaddition of CO2 with ECH.


Assuntos
Epicloroidrina , Compostos de Epóxi , Silicatos , Titânio , Dióxido de Carbono , Reação de Cicloadição , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Environ Sci Technol ; 58(1): 3-16, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38193155

RESUMO

Water reuse is rapidly becoming an integral feature of resilient water systems, where municipal wastewater undergoes advanced treatment, typically involving a sequence of ultrafiltration (UF), reverse osmosis (RO), and an advanced oxidation process (AOP). When RO is used, a concentrated waste stream is produced that is elevated in not only total dissolved solids but also metals, nutrients, and micropollutants that have passed through conventional wastewater treatment. Management of this RO concentrate─dubbed municipal wastewater reuse concentrate (MWRC)─will be critical to address, especially as water reuse practices become more widespread. Building on existing brine management practices, this review explores MWRC management options by identifying infrastructural needs and opportunities for multi-beneficial disposal. To safeguard environmental systems from the potential hazards of MWRC, disposal, monitoring, and regulatory techniques are discussed to promote the safety and affordability of implementing MWRC management. Furthermore, opportunities for resource recovery and valorization are differentiated, while economic techniques to revamp cost-benefit analysis for MWRC management are examined. The goal of this critical review is to create a common foundation for researchers, practitioners, and regulators by providing an interdisciplinary set of tools and frameworks to address the impending challenges and emerging opportunities of MWRC management.


Assuntos
Ultrafiltração , Águas Residuárias , Epicloroidrina , Nutrientes , Água
7.
Int J Biol Macromol ; 257(Pt 2): 128600, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38065448

RESUMO

The development of new coatings based on a biopolymer, epichlorohydrin-modified alginate, and alginate-epichlorohydrin-SrTiO3 nanocomposites incorporating SrTiO3 (STO) nanoparticles in the alginate (Alg) matrix (Alg-Ep-STO), has been addressed in this study. Various characterization techniques were employed to analyze the prepared compounds, including X-ray diffraction spectroscopy (XRD), Fourier-transform infrared spectroscopy (FTIR), as well as surface analysis methods such as Scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDX). Furthermore, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarisation (PDP) methods were used to evaluate corrosion inhibition and protection durability. The results demonstrate that the incorporation of STO nanoparticles into the alginate matrix with epichlorohydrin significantly improved the metal's resistance to corrosion. The experimental findings received reinforcement from various computational methods, including density functional theory (DFT), Molecular Dynamics (MD) and Monte Carlo (MC) simulations, which were employed to investigate the interactions between the Alg-Ep-STO nanocomposite and the copper surface. The computational outcomes revealed that the Alg-Ep-STO nanocomposite exhibits robust adhesion to the copper surface, maintaining a flat orientation, with its alignment being notably influenced by the presence of STO nanoparticles.


Assuntos
Cobre , Cloreto de Sódio , Alginatos/química , Epicloroidrina , Modelos Teóricos
8.
J Biochem Mol Toxicol ; 38(1): e23569, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37943572

RESUMO

Osteoarthritis (OA) is a joint pain and dysfunction syndrome resulting from severe joint degeneration. Inflammation and degeneration of the articular cartilage are two main features of OA and have tight interactions during OA progression. Conventional treatment with nonsteroidal anti-inflammatory drugs has been widely utilized clinically, whereas the side effects have restricted their application. Forsythoside B has been found with anti-inflammatory effects and antiapoptosis in inflammatory diseases, whereas in OA it remains poorly understood. Interleukin (IL)-1ß (10 ng/mL) was taken to induce an OA cell model on HC-A chondrocytes and an OA rat model was constructed for in vivo experiments. Forsythoside B was adopted to treat HC-A chondrocytes and OA rats. As shown by the data, Forsythoside B hampered IL-1ß-elicited rat chondrocyte apoptosis, oxidative stress, and facilitated proliferation. The profiles of inflammatory factors, NOD-like receptor family pyrin domain containing 3 inflammasomes, Kelch-like epichlorohydrin-associated protein-1 (Keap1), and nuclear factor-κB (NF-κB) phosphorylation were suppressed by Forsythoside B, whereas the nuclear factor E2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) levels were promoted. Further, Forsythoside B mitigated cartilage damage and degeneration. Moreover, the oxidative stress and inflammation mediators in the cartilage tissue of OA rats were remarkably abated. Collectively, Forsythoside B hinders the NF-κB and Keap1/Nrf2/HO-1 pathways to curb IL-1ß-elicited OA rat oxidative stress and inflammation both in vivo and ex vivo, ameliorating OA development. All over, this study provides an underlying strategy for treating OA, which might help the clinical treatment of OA patients.


Assuntos
Ácidos Cafeicos , Glucosídeos , Proteína HMGB1 , Osteoartrite , Humanos , Animais , Ratos , NF-kappa B/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Receptor 4 Toll-Like/metabolismo , Epicloroidrina/farmacologia , Epicloroidrina/uso terapêutico , Transdução de Sinais , Heme Oxigenase-1/metabolismo , Proteína HMGB1/metabolismo , Células Cultivadas , Osteoartrite/tratamento farmacológico , Osteoartrite/metabolismo , Inflamação/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Interleucina-1beta/metabolismo
9.
Curr Mol Med ; 24(3): 355-365, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-36959142

RESUMO

BACKGROUND: Oxidative stress is a key mechanism underlying arsenicinduced liver injury, the Kelch-like epichlorohydrin-related protein 1 (Keap1)/nuclear factor E2 related factor 2 (Nrf2) pathway is the main regulatory pathway involved in antioxidant protein and phase II detoxification enzyme expression. The aim of the present study was to investigate the role and mechanism of baicalein in the alleviation of arsenic-induced oxidative stress in normal human liver cells. METHODS: Normal human liver cells (MIHA cells) were treated with NaAsO2 (0, 5, 10, 20 µM) to observe the effect of different doses of NaAsO2 on MIHA cells. In addition, the cells were treated with DMSO (0.1%), NaAsO2 (20 µM), or a combination of NaAsO2 (20 µM) and Baicalein (25, 50 or 100 µM) for 24 h to observe the antagonistic effect of Baicalein on NaAsO2. Cell viability was determined using a Cell Counting Kit- 8 (CCK-8 kit). The intervention doses of baicalein in subsequent experiments were determined to be 25, 50 and 100µM. The intracellular content of reactive oxygen species (ROS) was assessed using a 2',7'-dichlorodihydrofluorescein diacetate (DCFHDA) probe kit. The malonaldehyde (MDA), Cu-Zn superoxide dismutase (Cu-Zn SOD) and glutathione peroxidase (GSH-Px) activities were determined by a test kit. The expression levels of key genes and proteins were determined by real-time fluorescence quantitative polymerase chain reaction (qPCR) and Western blotting. RESULTS: Baicalein upregulated the protein expression levels of phosphorylated Nrf2 (p-Nrf2) and nuclear Nrf2, inhibited the downregulation of Nrf2 target genes induced by arsenic, and decreased the production of ROS and MDA. These results demonstrate that baicalein promotes Nrf2 nuclear translocation by upregulating p-Nrf2 and inhibiting the downregulation of Nrf2 target genes in arsenic-treated MIHA cells, thereby enhancing the antioxidant capacity of cells and reducing oxidative stress. CONCLUSION: Baicalein alleviated arsenic-induced oxidative stress through activation of the Keap1/Nrf2 signalling pathway in normal human liver cells.


Assuntos
Antioxidantes , Arsênio , Flavanonas , Humanos , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Arsênio/toxicidade , Arsênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Epicloroidrina/metabolismo , Epicloroidrina/farmacologia , Estresse Oxidativo , Fígado
10.
Biomed Pharmacother ; 170: 116067, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38150877

RESUMO

BACKGROUND: Neuropathic pain, a chronic condition with a high incidence, imposes psychological burdens on both patients and society. It is urgent to improve pain management and develop new analgesic drugs. Traditional Chinese medicine has gained popularity as a method for pain relief. Diosmetin (Dio) is mainly found in Chinese herbal medicines with effective antioxidant, anti-cancer, and anti-inflammatory properties. There are few known mechanisms underlying the effectiveness of Dio in treating neuropathic pain. However, the complete understanding of its therapeutic effect is missing. PURPOSE: This study aimed to evaluate Dio's therapeutic effects on neuropathic pain models and determine its possible mechanism of action. We hypothesized that Dio may activate antioxidants and reduce inflammation, inhibit the activation of Kelch-like epichlorohydrin-associated protein 1 (Keap1) and nuclear factor-k-gene binding (NF-κB), promote the metastasis of nuclear factor erythroid 2-related factor 2 (Nrf2) and the expression of heme oxygenase 1 (HO-1), thus alleviating the neuropathic pain caused by spinal nerve ligation. METHODS: Chronic nociceptive pain mouse models were established in vivo by L4 spinal nerve ligation (SNL). Different dosages of Dio (10, 50, 100 mg/kg) were intragastrically administered daily from the third day after the establishment of the SNL model. Allodynia, caused by mechanical stimuli, and hyperalgesia, caused by heat, were assessed using the paw withdrawal response frequency (PWF) and paw withdrawal latency (PWL), respectively. Cold allodynia were assessd by acetone test. RT-PCR was used to detect the content of interleukin-(IL)- 1ß, IL-6 and tumor necrosis factor (TNF)-a. Immunofluorescence and western blotting were employed to assess the expression levels of Glial fibrillary acidic protein (GFAP), ionized calcium-binding adapter molecule (Iba1), Keap1, Nrf2, HO-1, and NF-κB p-p65 protein. RESULTS: Dio administration relieved SNL-induced transient mechanical and thermal allodynia in mice. The protective effect of Dio in the SNL model was associated with its anti-inflammatory and anti-glial responses in the spinal cord. Dio inhibited both inflammatory factors and macrophage activation in the DRG. Furthermore, Dio regulated the Keap1/Nrf2/NF-κB signaling pathway. HO-1 and Nrf2 were upregulated following Dio administration, which also decreased the levels of Keap1 and NF-κB p65 protein. CONCLUSION: Mice with SNL-induced neuropathic pain were therapeutically treated with Dio. Dio may protect against pain by inhibiting inflammatory responses and improved Keap1/Nrf2/NF-κB pathway. These results highlight the potential therapeutic effect of Dio for the development of new analgesic drugs.


Assuntos
NF-kappa B , Neuralgia , Humanos , Camundongos , Animais , NF-kappa B/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Epicloroidrina/uso terapêutico , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Hiperalgesia/tratamento farmacológico , Transdução de Sinais , Analgésicos/farmacologia , Analgésicos/uso terapêutico , Neuralgia/patologia , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico
11.
Environ Sci Pollut Res Int ; 30(49): 107772-107789, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37740156

RESUMO

Nitrates level in water is a worldwide problem that represents a risk to the environment and people's health; efforts are currently devoted to the development and implementation of new biomaterials for their removal. In this study, chitosan (Ch) from shrimp waste and the related epichlorohydrin-modified crossover chitosan (Ch-EPI) were used to remove nitrates from aqueous solutions. The mechanism of selective nitrate removal was elucidated and validated by theoretical calculations. The physicochemical performance of Ch and Ch-EPI was investigated through the main parameters pH, adsorption capacity, contact time, initial nitrate concentration, coexisting anions, and temperature. The experimental data were fitted to widely used adsorption kinetic models and adsorption isotherms. The maximum percentage of nitrate adsorption was reached at an equilibrium pH of 4.0 at an adsorbent dose of 2.0 g/L after a contact time of 50 min. Competing anion experiments show that chloride and sulfate ions have minimal and maximal effects on nitrate adsorption by Ch-EPI. Experimental adsorption data are best fitted to pseudo-second-order kinetic and isothermal Langmuir models. The maximum adsorption capacities of Ch and Ch-EPI for nitrate removal were 12.0 mg/g and 38 mg/g, respectively.


Assuntos
Quitosana , Poluentes Químicos da Água , Humanos , Nitratos , Epicloroidrina , Ânions , Água , Adsorção , Cinética , Modelos Teóricos , Concentração de Íons de Hidrogênio
12.
J Hazard Mater ; 460: 132490, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37703728

RESUMO

Hydraulic fracturing for oil and gas extraction produces large volumes of wastewater, termed flowback and produced water (FPW), that are highly saline and contain a variety of organic and inorganic contaminants. In the present study, FPW samples from ten hydraulically fractured wells, across two geologic formations were collected at various timepoints. Samples were analyzed to determine spatial and temporal variation in their inorganic composition. Results indicate that FPW composition varied both between formations and within a single formation, with large compositional changes occurring over short distances. Temporally, all wells showed a time-dependent increase in inorganic elements, with total dissolved solids increasing by up to 200,000 mg/L over time, primarily due to elements associated with salinity (Cl, Na, Ca, Mg, K). Toxicological analysis of a subset of the FPW samples showed median lethal concentrations (LC50) of FPW to the aquatic invertebrate Daphnia magna were highly variable, with the LC50 values ranging from 1.16% to 13.7% FPW. Acute toxicity of FPW significantly correlated with salinity, indicating salinity is a primary driver of FPW toxicity, however organic components also contributed to toxicity. This study provides insight into spatiotemporal variability of FPW composition and illustrates the difficulty in predicting aquatic risk associated with FPW.


Assuntos
Fraturamento Hidráulico , Animais , Daphnia , Epicloroidrina , Dose Letal Mediana , Água
13.
Int J Biol Macromol ; 249: 125983, 2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37494996

RESUMO

This paper reports a synergic binding technique of dye and cadmium/lead ions onto freeze-dried modified chitosan beads (GCCS), in this work modified chitosan beads was applied in binary solution. Chitosan beads (CS) composite was produced and polyethyleneimine was grafted onto the backbone of the developed composite. The beads were analyzed utilizing different analytical techniques such as Fourier transform infrared (FTIR), thermogravimetric analysis (TGA), X-ray diffraction (XRD) and scanning electron microscope (SEM). The model applied in pH equilibrium was found to justify the adsorption of pollutants onto the adsorbent. The model was established from 2 equilibrium calculations, one justifying the acid-base attributes of the modified beads, the other elucidating the adsorption of the adsorbates onto the beads, and a mass balance of the various arrangement of nitrogen in the adsorbent. The excellent fit of the Pseudo-second order and intra-particle diffusion kinetic model shows that chemical binding might be the rate-limiting step. The adsorption isotherms were well represented by the Langmuir and Temkin models at a temperature of 45 °C. The maximum binding capacities (Qmax) from the Langmuir model were observed to be 390, 315 and 278 mg/g for the adsorption of dye, lead and cadmium ions respectively`. However, it was found to be higher in the binary system with the same applicable conditions. The correlation was analyzed utilizing various models and lines of best fit were obtained. Synergic effect was observed from the experimental results acquired from the adsorption of Rhodamine B (RHB) and adsorbates. These findings show the formation of fresh binding sites during simultaneous binding process.


Assuntos
Quitosana , Metais Pesados , Poluentes Químicos da Água , Quitosana/química , Epicloroidrina/química , Polietilenoimina , Cádmio , Poluentes Químicos da Água/química , Metais Pesados/química , Rodaminas , Íons/química , Adsorção , Cinética , Concentração de Íons de Hidrogênio
14.
Int J Biol Macromol ; 247: 125503, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37348580

RESUMO

Epichlorohydrin-modified chitosan-Schiff base composite (CS/24Cl/ECH) prepared via the one-pot reaction as characterized by Fourier transform Infra-Red spectroscopy (FT-IR), X-ray powder diffraction (XRD), Differential scanning calorimetry (DSC) and Scanning electron microscope (SEM). Its removal ability of Pb(II) ions from aqueous solution was investigated. The adsorption of Pb(II) ions carried out at different initial pH, dose of CS/24-Cl/ECH, contact time and co-existing ions. The maximum adsorption capacity of Pb(II) ions was 170 mg/g. Finally, based on the absorption results, the adsorption of Pb(II) ions was fitted by single-layer Langmuir isotherm model and the pseudo-second-order (PSO) kinetics model. The absorption mechanism of Pb(II) ions was controlled by chemical coordination Pb(II) ions with the active sites on the surface of CS/24Cl/ECH composite. Also, CS/24Cl/ECH showed excellent recyclable efficiency up to 5 cycle and potential sorbent for other heavy metal ions.


Assuntos
Quitosana , Poluentes Químicos da Água , Quitosana/química , Epicloroidrina/química , Chumbo , Espectroscopia de Infravermelho com Transformada de Fourier , Adsorção , Íons/química , Cinética , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio
15.
Int J Biol Macromol ; 242(Pt 2): 124786, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37169046

RESUMO

Chitosan/bentonite beads (CsB) composites were prepared from chitosan (Cs) and bentonite (B) and cross-linked with epichlorohydrin for removal of reactive orange 16 (RO16) and methylene blue (MB). The adsorption results have shown that the (Cs20B80), 20 % wt of (Cs) and 80 % (B), was selected as the best adsorbent for (MB) and (RO16) dyes. SEM, EDX, FTIR, BET, and pHpzc were implemented to investigate the features of Cs, B, and Cs20B80 samples. The influence of contact time (0-72 h), initial RO16 concentration (15-300 mg/L), temperature (30, 40, and 50 °C), the quantity of adsorbent (1-4 g/L), ion strength (0.1-1 M), and solution pH (3-10) on RO16 adsorption onto Cs20B80 were explored. The pseudo-second-order and the Langmuir models fit adequately the adsorption kinetic results and the isotherms ones respectively. Also, the maximal monolayer capacities calculated using the non-linear form of the Langmuir isotherm are 55.27, 55.29, and 70.80 mg/g, at 30, 40 and 50 °C. Based to the statistical physics model, the RO16 could be retained on the surface of Cs20B80 through a non-parallel orientation. The RO16 adsorption process is endothermic and natural, as demonstrated by thermodynamic studies. After three regeneration cycles, the Cs20B80 composite has shown an adsorption capacity of around 20 % compared to the initial one. The adsorption energy of RO16 onto Cs, B, and Cs20B80 examined using the Monte Carlo simulation method (MC) ranged from -164.8 to -303.7 (kcal/mol), showing the potential of the three adsorbants for RO16 dye. Also, the process of adsorption of RO16 dye on the surface of Cs20B80 composite indicates several kinds of physical interactions, involving electrostatic interaction, hydrogen bonding, and π-π interactions, this finding was proved theoretically via molecular dynamic simulations.


Assuntos
Quitosana , Poluentes Químicos da Água , Quitosana/química , Corantes/química , Bentonita/química , Epicloroidrina/química , Simulação de Dinâmica Molecular , Cinética , Termodinâmica , Adsorção , Concentração de Íons de Hidrogênio , Poluentes Químicos da Água/química
16.
J Med Chem ; 66(12): 8267-8280, 2023 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-37257073

RESUMO

Blocking the Kelch-like epichlorohydrin-related protein 1 (Keap1)-nuclear factor-erythroid 2 related factor 2 (Nrf2) pathway is a promising strategy to alleviate acute lung injury (ALI). A naphthalensulfonamide NXPZ-2, targeting Keap1-Nrf2 interaction to release Nrf2, was confirmed to exhibit significant anti-inflammatory activities, however, accompanying nonideal solubility and PK profiles. To further improve the properties, twenty-nine novel naphthalenesulfonamide derivatives were designed by a fragment-based strategy. Among them, compound 10u with a (R)-azetidine group displayed the highest PPI inhibitory activity (KD2 = 0.22 µM). The hydrochloric acid form of 10u exhibited a 9-fold improvement on water solubility (S = 484 µg/mL, pH = 7.0) compared to NXPZ-2 (S = 55 µg/mL, pH = 7.0). It could significantly reduce LPS-induced lung oxidative damages and inflammations in vitro and in vivo. Furthermore, a satisfactory pharmacokinetic property was revealed. In conclusion, the novel azetidine-containing naphthalenesulfonamide represents a promising drug candidate for Keap1-targeting ALI treatment.


Assuntos
Lesão Pulmonar Aguda , Fator 2 Relacionado a NF-E2 , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Epicloroidrina , Lesão Pulmonar Aguda/tratamento farmacológico
17.
J Mol Graph Model ; 122: 108485, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37084666

RESUMO

In this study, theoretically designed D-π-A derivatives containing different π-subunits as linkers were investigated to enlighten their potential applicability in photovoltaic applications. For this aim, we first focused on clarifying the effect of tailored π-linker scaffolds on the frontier orbital energies of the investigated photosensitizers. In the concomitant step, global descriptors, TiO2 adsorption, maximum absorbance wavelength, light-harvesting efficiency (LHE), energy conversion efficiency (η), short circuit current density (JSC), open circuit photovoltage (VOC), fill factor (FF), and reorganization energy (λe, λh, λT) values, electron density differentiation maps (EDDM), transition density matrices (TDM), fragmental contributions on electron-hole overlap were investigated in detail. Based on the trend of the calculated properties, 2,3-dimethylthieno [3,4-b]pyrazine (D-Ɛ3-δn-A; n = 1-3) and 5-isobutyl-10,11-dimethyl-10,11-dihydro-5H-pyrrolo [3,4-e]thieno [2',3':4,5]pyrrolo [3,2-g]thieno [3,2-b]indole (D-Ɛ6-δn-A; n = 1-3) bearing molecules were identified as the best-suited and improved dye candidates for DSSC applications. Following the prediction of photovoltaic properties for the pristine dye molecules, our consecutive efforts have contributed to a similar calculation protocol comprising DFT and subsequent TD-DFT computations for the D-Ɛn-δn-A@Ti5O10 clusters to elucidate the interaction of the investigated photosensitizers with the semiconductor layer (TiO2).


Assuntos
Epicloroidrina , Fármacos Fotossensibilizantes , Adsorção
18.
J Food Sci ; 88(5): 2168-2177, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36988107

RESUMO

The classic Coffee Brewing Control Chart (BCC) was originally developed in the 1950s. It relates coffee quality to brew strength and extraction yield, and it is still widely used today by coffee industry professionals around the world to provide guidance on the brewing of coffee. Despite its popularity, recent experimental studies have revealed that sensory attributes and consumer preferences actually follow much more complicated trends than those indicated by the classic BCC. Here, we present a methodology to synthesize the results of these recent studies on drip-brewed coffee to generate new versions of the BCC: a new Sensory BCC that displays a broad array of statistically significant sensory attributes across typical total dissolved solids and percent extraction ranges, a new Consumer BCC that highlights the existence of two preference clusters with different likes and dislikes across those ranges, a new Sensory and Consumer BCC that combines both sensory descriptive and consumer preferences on the same chart, and a more streamlined BCC that omits consumer preferences and focuses on the overarching sensory descriptive trends. The new BCCs provide more accurate insight on how best to brew coffee to achieve desired sensory profiles. PRACTICAL APPLICATION: Through the manipulation of yield and extraction parameters, the new Sensory and Consumer Coffee Brewing Control Chart presented here can be used by brewers of drip coffee to design coffees with specific sensory profiles and match the preferences of different consumer types.


Assuntos
Coffea , Café , Comportamento do Consumidor , Emoções , Epicloroidrina
19.
Dev Comp Immunol ; 141: 104629, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36587710

RESUMO

Microcystins (MC) are one of the most abundant and widely distributed cyanotoxins in aquatic systems. MC inhibits the functions of protein phosphatase 1 and 2A (PP1/2A), which can seriously affect ecosystem integrity. The NF-E2-related nuclear factor 2 (Nrf2)/Kelch-like epichlorohydrin-related protein-1 (Keap1) signaling pathway protects against oxidative damage by activating phase II detoxification/antioxidant enzymes. Our previous study revealed that MC upregulates the expression and enhances the activities of the antioxidant enzymes by stimulating the CpNrf2 signaling pathway. In the current study, to further clarify the regulatory role of Keap1 in response to MC-induced oxidative stress in shellfish, we cloned the full-length cDNA of Keap1a and Keap1b from Cristaria plicata (designated CpKeap1a and CpKeap1b), which are 2952 and 3710 bp peptides, respectively. The amino acid sequence of CpKeap1a and CpKeap1b contained Tram-track and Bric-a-brac (BTB), Intervening region (IVR), and Double glycine repeat (DGR) domain. Additionally, CpKeap1a contained two cysteine residues analogous to Cys-273 and -288 in zebrafish, but CpKeap1b did not. Moreover, CpKeap1a and -1b formed a homodimer and heterodimer, respectively, and also formed a heterodimer with CpNrf2. In the hepatopancreas, the expression levels of CpKeap1a and -1b were the highest, but MC treatment down-regulated the expression of these proteins. Moreover, the transcription of antioxidant enzymes with antioxidant response element (ARE-driven enzymes), including CpMnSOD, CpCu/ZnSOD, CpTRX, CpPrx, CpSe-GPx, and Cpsigma-GST was upregulated by CpNrf2 in the hepatopancreas. Compared with the MC-induced group, CpKeap1a-siRNA1117 injection significantly increased the transcription of mRNAs for ARE-driven enzymes and Nrf2. CpKeap1a-siRNA1117 also enhanced the activities of antioxidation enzymes. These findings demonstrated that Keap1a negatively regulated the expression of Nrf2 protein and MC-induced oxidative stress response in C. plicata. Therefore, we speculated that CpKeap1a promoted CpNrf2 by recognizing and binding MC. These events then protected molluscs from MC-induced oxidative damage.


Assuntos
Bivalves , Unionidae , Animais , Antioxidantes/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Epicloroidrina , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Peixe-Zebra/metabolismo , Microcistinas/metabolismo , Ecossistema , Bivalves/genética , Unionidae/genética , Estresse Oxidativo , Proteínas de Transporte/metabolismo , Proteínas de Peixe-Zebra/genética
20.
Carbohydr Polym ; 302: 120389, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36604067

RESUMO

Developing affordable and effective carbon dioxide (CO2) capture technology has attracted substantial intense attention due to the continued growth of global CO2 emissions. The low-cost and biodegradable cellulosic materials are developed into CO2 adsorbent recently. Epoxy-functionalized polyethyleneimine modified epichlorohydrin-cross-linked cellulose aerogel (EBPCa) was synthesized from alkaline cellulose solution, epoxy-functionalized polyethyleneimine (EB-PEI), and epichlorohydrin (ECH) through the freezing-thawing processes and freeze-drying. The Fourier transform infrared spectroscopy confirmed that the cellulose aerogel was successfully modified by EB-PEI. The X-ray photoelectron spectroscopy analyses confirmed the presence of N 1s and Cl 2p in EBPCa, meaning that the chlorine of ECH and the amino groups of EB-PEI exist in the cellulose surface. The obtained sample has a rich porous structure with a specific surface area in the range of 97.5-149.5 m2/g. Owing to its uniformly three-dimensional porous structure, the sample present preferable rigidity and carrying capacity, which 1 g of sample could easily carry the weight of a 3000 ml Erlenmeyer flask filled with water (total 4 kg). The sample showed good adsorption performance, with a maximum adsorption capacity of 6.45 mmol/g. This adsorbent has broad prospects in the CO2 capture process.


Assuntos
Dióxido de Carbono , Celulose , Celulose/química , Dióxido de Carbono/química , Polietilenoimina/química , Epicloroidrina , Espectroscopia de Infravermelho com Transformada de Fourier , Adsorção , Cloretos
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