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1.
Phys Chem Chem Phys ; 25(15): 10481-10494, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36987608

RESUMO

Choline chloride (ChCl)-carboxylic acid deep eutectic solvents (DESs) are promising green solvents for lignocellulose pretreatment, de-aromatization of gasoline, battery recycling, etc. Micro interactions determine the physical properties of DESs, such as melting point, viscosity, and solubility. In the present work, the structures of choline chloride/formic acid (FA) and choline chloride/acetic acid (AA) with a 1 : 2 molar ratio were investigated by wide-angle X-ray scattering, empirical potential structure refinement (EPSR) and density functional theory (DFT) calculations. Reduced density gradient (RDG) and atoms in molecules (AIM) show that hydrogen bonds and carbon-hydrogen bonds exist in choline chloride-carboxylic acid DESs. EPSR modelling based on the gauche choline cation model reveals the interactions between DES components. Cl- plays an important role in maintaining the structural stability of choline chloride-carboxylic acid DESs, by participating in the formation of hydrogen bonds, carbon-hydrogen bonds, and acting as a bridge for indirect interaction, including between choline cations and carboxylic acid molecules. Molecular size and steric hindrance elucidate the formation of different sizes of clusters (≤10 molecules) and chains (≤5 molecules) in DESs. Spatial density functions show that formic acid and acetic acid have a strong orientational preference. The strong interaction between Ch+ and FA and the existence of the Cl- bridge significantly destroyed the lattice structure of ChCl, resulting in the melting point of ChClFA (<-90 °C) being lower than that of ChClAA (-8.98 °C). This fundamental understanding of the structure will enable the development of green, economical, and nontoxic choline chloride-carboxylic acid DESs.

2.
Zhongguo Zhong Yao Za Zhi ; 48(2): 399-414, 2023 Jan.
Artigo em Zh | MEDLINE | ID: mdl-36725230

RESUMO

This study aims to explore the chemical composition of Rehmanniae Radix braised with mild fire and compare the effect of processing method on the chemical composition of Rehmanniae Radix. To be specific, ultra-high performance liquid chromatography with linear ion trap-orbitrap mass spectrometry(UHPLC-LTQ-Orbitrap MS) was used to screen the chemical constituents of Rehmanniae Radix. The chemical constituents were identified based on the relative molecular weight and fragment ions, literature information, and Human Metabolome Database(HMDB). The ion peak area ratio of each component before and after processing was used as the index for the variation. SIMCA was employed to establish principal component analysis(PCA) and orthogonal partial least squares discriminant analysis(OPLS-DA) models of different processed products. According to the PCA plot, OPLS-DA plot, and VIP value, the differential components before and after the processing were screened out. The changes of the content of differential components with the processing method were analyzed. A total of 66 chemical components were identified: 57 of raw Rehmanniae Radix, 55 of steamed Rehmanniae Radix, 55 of wine-stewed Rehmanniae Radix, 51 of repeatedly steamed and sundried Rehmanniae Radix Praeparata, 62 of traditional bran-braised Rehmanniae Radix, and 63 of electric pot-braised Rehmanniae Radix. Among them, the 9 flavonoids of braised Rehmanniae Radix were from Citri Reticulatae Pericarpium. PCA suggested significant differences in the chemical composition of Rehmanniae Radix Praeparata prepared with different processing methods. OPLS-DA screened out 32 chemical components with VIP value >1 as the main differential components. Among the differential components, 9 were unique to braised Rehmanniae Radix(traditional bran-braised, electric pot-braised) and the degradation rate of the rest in braised(traditional bran-braised, electric pot-braised) or repeatedly steamed and sundried Rehmanniae Radix was higher than that in the steamed or wine-stewed products. The results indicated the chemical species and component content of Rehmanniae Radix changed significantly after the processing. The 32 components, such as rehmapicrogenin, martynoside, jionoside D, aeginetic acid, hesperidin, and naringin, were the most important compounds to distinguish different processed products of Rehmanniae Radix. The flavonoids introduced by Citri Reticulatae Pericarpium as excipient may be the important material basis for the effectiveness of braised Rehmanniae Radix compared with other processed products.


Assuntos
Medicamentos de Ervas Chinesas , Rehmannia , Humanos , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/química , Extratos Vegetais/química , Rehmannia/química , Flavonoides/análise
3.
Inorg Chem ; 61(47): 18998-19009, 2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36378068

RESUMO

By introducing Brønsted acidic ionic liquids (ILs), two dual-emitting lanthanide metal-organic complexes (Ln-MOCs) of {[Ln(imdc)(CH3OH)(H2O)3]Cl2}n (LnIMDC, Ln = Eu and Tb, imdc = 1,3-bis(carboxymethyl)imidazolium ion) were first prepared under solvothermal conditions. The crystal structures of LnIMDC were measured by single-crystal X-ray diffraction, and the crystal growth process of LnIMDC was carefully studied. It is found that the crystals are three-dimensional supramolecular structures built up by Ln-O coordination bonds and supramolecular forces. In the temperature range of 303-403 K, LnIMDC show good temperature-dependent emission properties with maximum relative thermal sensitivities of 3.29% K-1 at 375 K and 2.08% K-1 at 303 K for EuIMDC and TbIMDC, respectively. It is worth mentioning that both EuIMDC and TbIMDC exhibit good linear ratiometric emission-temperature response in temperature ranges of 353-403 and 323-373 K, respectively, which render EuIMDC and TbIMDC good ratiometric thermometers in high temperature range. Computational studies on the energy level of ILs [H2imdc]Cl and [imdc]- ion were performed, which validated the high energy transfer efficiency between the [imdc]- and Ln3+ ions and the unique solution concentration- and wavelength-dependent fluorescence properties of [H2imdc]Cl. The high fluorescence performance opens up new opportunities for practical applications of ILs in optical sensing.

4.
Acta Pharmacol Sin ; 43(10): 2651-2665, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35217814

RESUMO

Canagliflozin is an antidiabetic medicine that inhibits sodium-glucose cotransporter 2 (SGLT2) in proximal tubules. Recently, it was reported to have several noncanonical effects other than SGLT2 inhibiting. However, the effects of canagliflozin on skeletal muscle regeneration remain largely unexplored. Thus, in vivo muscle contractile properties recovery in mice ischemic lower limbs following gliflozins treatment was evaluated. The C2C12 myoblast differentiation after gliflozins treatment was also assessed in vitro. As a result, both in vivo and in vitro data indicate that canagliflozin impairs intrinsic myogenic regeneration, thus hindering ischemic limb muscle contractile properties, fatigue resistance recovery, and tissue regeneration. Mitochondrial structure and activity are both disrupted by canagliflozin in myoblasts. Single-cell RNA sequencing of ischemic tibialis anterior reveals a decrease in leucyl-tRNA synthetase 2 (LARS2) in muscle stem cells attributable to canagliflozin. Further investigation explicates the noncanonical function of LARS2, which plays pivotal roles in regulating myoblast differentiation and muscle regeneration by affecting mitochondrial structure and activity. Enhanced expression of LARS2 restores the differentiation of canagliflozin-treated myoblasts, and accelerates ischemic skeletal muscle regeneration in canagliflozin-treated mice. Our data suggest that canagliflozin directly impairs ischemic skeletal muscle recovery in mice by downregulating LARS2 expression in muscle stem cells, and that LARS2 may be a promising therapeutic target for injured skeletal muscle regeneration.


Assuntos
Aminoacil-tRNA Sintetases , Inibidores do Transportador 2 de Sódio-Glicose , Aminoacil-tRNA Sintetases/metabolismo , Aminoacil-tRNA Sintetases/farmacologia , Animais , Canagliflozina/metabolismo , Canagliflozina/farmacologia , Canagliflozina/uso terapêutico , Diferenciação Celular , Glucose/metabolismo , Hipoglicemiantes/metabolismo , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Isquemia/tratamento farmacológico , Isquemia/metabolismo , Camundongos , Músculo Esquelético/metabolismo , Sódio/metabolismo , Sódio/farmacologia , Transportador 2 de Glucose-Sódio/metabolismo , Transportador 2 de Glucose-Sódio/farmacologia , Inibidores do Transportador 2 de Sódio-Glicose/metabolismo , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia
5.
Phys Chem Chem Phys ; 23(34): 18659-18668, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34612403

RESUMO

Ionic liquids (ILs) have shown high catalytic activity in the degradation of poly(ethylene terephthalate) (PET), but the effects of the anions and cations, as well as the mechanism, remain ambiguous. Glycolysis is an important recycling method that converts waste PET into monomers through various chemical reactions. To reveal the role of ILs and the molecular mechanism of the glycolysis of PET, density functional theory (DFT) calculations have been carried out for the possible pathways for the generation of bis(hydroxyethyl)terephthalate (BHET) catalyzed by isolated anions/cations and ion pairs at different sites. The pathway with the lowest barrier for the glycolysis of PET is the cleavage of the C-O ester bond, which generates the BHET monomer. The synergistic effects of the cations and anions play a critical role in the glycolysis of PET. The cations mainly attack the carbonyl oxygen of PET to catalyze the reaction, and the anions mainly form strong H-bonds with PET and ethylene glycol (EG). In terms of the mechanism, the H-bonds render the hydroxyl oxygen of EG more electronegative. The cation coordinates the carbonyl oxygen of the ester, and the hydroxyl oxygen of EG attacks the ester group carbon of PET, with proton transfer to the carbonyl oxygen. A four-membered-ring transition state would be formed by PET, EG, and the IL catalyst, which regularly accelerates the degradation of PET. These results provide fundamental help in understanding the roles of ILs and the mechanism of IL-catalyzed PET degradation.

6.
J Environ Manage ; 296: 113267, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34271351

RESUMO

This paper briefly reviews the development history of polyethylene terephthalate (PET) and the recycling of PET. As one of the most promising way to degrade PET into oligomers and monomers that can be used for the production of high-quality PET, catalytic glycolysis is highlighted in this review. The developments on metal salt, metal oxide and ionic solvent catalysts for glycolysis of PET are systematically summarized, besides, the proposed catalytic mechanisms of ionic liquids (ILs) and deep eutectic solvents (DESs) are presented. The metallic catalysts show high catalytic performance but causing serious environmental pollution and high waste treatment costs, thereby it is proposed that metal-free catalysts, especially ILs and DESs can be the "greener" alternatives to address the PET waste problem. Additionally, the studies related to the glycolysis kinetics are discussed in this review, showing the results that PET glycolysis process consists of heterogeneous and homogeneous depolymerization, and different models should be used to investigate different depolymerization stages in order to obtain a more realistic picture.


Assuntos
Líquidos Iônicos , Polietilenotereftalatos , Catálise , Glicólise , Reciclagem
7.
J Cell Biochem ; 120(9): 16244-16253, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31081255

RESUMO

BACKGROUND: Wound healing is a complex process in bone development. The aim of this study was to explore the molecular mechanism study of insulin in promoting wound healing. METHODS: Firstly, the acute human monocyte leukemia cell lines were induced to differentiate into macrophages. Secondly, the porphyromonas gingivalis was applied to mix with the differentiated macrophages. Thirdly, the effect of different concentrations of insulin (0 ng/mL, 5 ng/mL, 50 ng/mL, 100 ng/mL, 200 ng/mL, 500 ng/mL, and 1,000 ng/mL) on the phagocytosis of macrophages and production of reactive oxygen species was investigated. Depending on these experiments, the optimal insulin concentration was used to treat the macrophages at different time points (0 hours and 0.5 hours) to identify the differentially expressed mRNAs. Finally, functional analysis including gene ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) and protein-protein interaction (PPI) analysis was carried out to explore the biological function of these differentially expressed mRNAs. RESULTS: The test of phagocytosis function and production of reactive oxygen species showed that 200 ng/mL insulin treatment had a significant influence on antibacterial and production of reactive oxygen species. In RNA sequencing, a total of 415 (245 upregulated and 170 downregulated) differentially expressed mRNAs were identified between different time points. Two important signaling pathways including endocytosis and systemic lupus erythematosus were found in the KEGG enrichment analysis. In the PPI network, several hub proteins encoded by differentially expressed mRNA including ALB, HIP1R, RAB5A, HIST1H2BJ, HIST1H3G, and HIST1H2BO were identified. CONCLUSION: Our work demonstrated that several differentially expressed mRNAs, such as EGR1, RAB34, ALB, HIP1R, RAB5A, HIST1H2BJ, HIST1H3G, and HIST1H2BO and two important signaling pathways including endocytosis and systemic lupus erythematosus may play important roles in the bone wound healing.


Assuntos
Perfilação da Expressão Gênica/métodos , Redes Reguladoras de Genes , Glucose/farmacologia , Insulina/farmacologia , Macrófagos/citologia , Diferenciação Celular , Linhagem Celular Tumoral , Ontologia Genética , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Porphyromonas gingivalis/efeitos dos fármacos , Mapas de Interação de Proteínas , Espécies Reativas de Oxigênio/metabolismo , Análise de Sequência de RNA , Cicatrização
9.
Cell Biochem Funct ; 37(5): 385-394, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31140646

RESUMO

To explore the molecular mechanism of insulin on proliferation and differentiation of MC3T3-E1 cell under high glucose conditions. We first investigated the effect of different concentrations of insulin on the osteoblast cell proliferation and cell differentiation at various time points by MTT analysis, cell cycle analysis, and expression detection of differentiation genes. Then, we used 200 ng/mL of insulin to treat the osteoblast cell at different time points for identifying the common differentially expressed mRNAs among various time points by RNA sequencing. Thirdly, we performed the gene ontology (GO) and the Kyoto Encyclopaedia of Genes and Genomes (KEGG) analysis to explore the biological function of these common differentially expressed mRNAs. The results showed that insulin promoted the cell proliferation and differentiation of osteoblast cell. In RNA sequencing, a total of 31 common differentially expressed mRNAs were identified between different time points. Mt1, Tmem135, Avp, and Dlg2 were found to be associated with the new bone formation. In addition, three important signalling pathways, namely, lysosome, glutamatergic synapse, and chemokine signalling pathways, were found in the KEGG enrichment analysis. Our work demonstrated that insulin could promote the osteoblast cell proliferation and cell differentiation, which may play a key role in bone formation. SIGNIFICANCE OF THE STUDY: Our result showed that insulin could promote the proliferation and differentiation of osteoblast at both cellular and molecular levels, which may promote the new bone formation in the osteoblasts.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Glucose/metabolismo , Insulina/farmacologia , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Células 3T3 , Animais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Camundongos , Osteoblastos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
10.
Phys Chem Chem Phys ; 19(30): 19967-19974, 2017 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-28722050

RESUMO

Refractive index is one of the important physical properties, which is widely used in separation and purification. In this study, the refractive index data of ILs were collected to establish a comprehensive database, which included about 2138 pieces of data from 1996 to 2014. The Group Contribution-Artificial Neural Network (GC-ANN) model and Group Contribution (GC) method were employed to predict the refractive index of ILs at different temperatures from 283.15 K to 368.15 K. Average absolute relative deviations (AARD) of the GC-ANN model and the GC method were 0.179% and 0.628%, respectively. The results showed that a GC-ANN model provided an effective way to estimate the refractive index of ILs, whereas the GC method was simple and extensive. In summary, both of the models were accurate and efficient approaches for estimating refractive indices of ILs.

11.
Chemphyschem ; 17(3): 335-51, 2016 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-26530378

RESUMO

Due to their attractive physico-chemical properties, ionic liquids (ILs) are increasingly used as deposition electrolytes. This review summarizes recent advances in electrodeposition in ILs and focuses on its similarities and differences with that in aqueous solutions. The electrodeposition in ILs is divided into direct and template-assisted deposition. We detail the direct deposition of metals, alloys and semiconductors in five types of ILs, including halometallate ILs, air- and water-stable ILs, deep eutectic solvents (DESs), ILs with metal-containing cations, and protic ILs. Template-assisted deposition of nanostructures and macroporous structures in ILs is also presented. The effects of modulating factors such as deposition conditions (current density, current density mode, deposition time, temperature) and electrolyte components (cation, anion, metal salts, additives, water content) on the morphology, compositions, microstructures and properties of the prepared materials are highlighted.

12.
Phys Chem Chem Phys ; 17(27): 17894-905, 2015 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-26095890

RESUMO

In recent years, a variety of ionic liquids (ILs) were found to be capable of dissolving cellulose and mechanistic studies were also reported. However, there is still a lack of detailed information at the molecular level. Here, long time molecular dynamics simulations of cellulose bunch in 1-ethyl-3-methylimidazolium acetate (EmimAc), 1-ethyl-3-methylimidazolium chloride (EmimCl), 1-butyl-3-methylimidazolium chloride (BmimCl) and water were performed to analyze the inherent interaction and dissolving mechanism. Complete dissolution of the cellulose bunch was observed in EmimAc, while little change took place in EmimCl and BmimCl, and nothing significant happened in water. The deconstruction of the hydrogen bond (H-bond) network in cellulose was found and analyzed quantitatively. The synergistic effect of cations and anions was revealed by analyzing the whole dissolving process. Initially, cations bind to the side face of the cellulose bunch and anions insert into the cellulose strands to form H-bonds with hydroxyl groups. Then cations start to intercalate into cellulose chains due to their strong electrostatic interaction with the entered anions. The H-bonds formed by Cl(-) cannot effectively separate the cellulose chain and that is the reason why EmimCl and BmimCl dissolve cellulose more slowly. These findings deepen people's understanding on how ILs dissolve cellulose and would be helpful for designing new efficient ILs to dissolve cellulose.


Assuntos
Celulose/química , Líquidos Iônicos/química , Simulação de Dinâmica Molecular , Ligação de Hidrogênio , Imidazóis/química , Eletricidade Estática , Termodinâmica , Água/química
13.
Int J Biol Macromol ; 255: 128125, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37984571

RESUMO

Transforming lignin into aromatic monomers is critically attractive to develop green and sustainable energy supplies. However, the usage of the additional catalysts like metal or base/acid is commonly limited by the caused repolymerized and environmental issues. The key step is to mediate electron transfer in lignin to trigger lignin C-C/C-O bonds cleavage without the catalysts mentioned above. Here, we report that the ionic liquids [BMim][ClO4] was found to trigger lignin electron transfer to cleave the C-C/C-O bonds for aromatic monomers without any additional catalyst. The proton transfer from [BMim]+ to [ClO4]- could polarize the anion and decrease its structure stability, upon which the active hydroxyl radical generated and induced lignin C-C/C-O bonds fragmentation via free radical-mediated routes with the assistance of photothermal synergism. About 4.4 wt% yields of aromatic monomers, mainly composed of vanillin and acetosyringone, are afforded in [BMim][ClO4] under UV-light irradiation in the air at 80 °C. This work opens the way to produce value-added aromatic monomers from lignin using an eco-friendly, energy-efficient, and simple route that may contribute to the sustainable utilization of renewable natural resources.


Assuntos
Líquidos Iônicos , Líquidos Iônicos/química , Lignina/química , Álcalis , Percloratos , Catálise
14.
J Hazard Mater ; 465: 133203, 2024 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-38103294

RESUMO

Antibacterial compounds that reduce extracellular polymeric substances (EPS) are needed to avoid bacterial biofilms in water pipelines. Herein, green one-pot synthesis of α-aminophosphonates (α-Amps) [A-G] was achieved by using ionic liquid (IL) as a Lewis acid catalyst. The synthesized α-Amp analogues were tested against different bacteria such as Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa. The representative [B] analogue showed an efficient antibacterial effect with MIC values of 3.13 µg/mL for E. coli, P. aeruginosa, and 6.25 µg/mL for B. subtilis. Additionally, a strong ability to eliminate the mature bacterial biofilm, with super-MIC values of 12.5 µg/mL for E. coli, P. aeruginosa, and 25 µg/mL for B. subtilis. Moreover, bacterial cell disruption by ROS formation was also tested, and the compound [B] revealed the highest ROS level compared to other compounds and the control, and efficiently destroyed the extracellular polymeric substances (EPS). The docking study confirmed strong interactions between [B] analogue and protein structures with a binding affinity of -6.65 kCal/mol for the lyase protein of gram-positive bacteria and -6.46 kCal/mol for DNA gyrase of gram-negative bacteria. The results showed that α-Amps moiety is a promising candidate for developing novel antibacterial and anti-biofilm agents for clean water supply.


Assuntos
Antibacterianos , Escherichia coli , Antibacterianos/química , Simulação de Acoplamento Molecular , Espécies Reativas de Oxigênio , Bactérias , Biofilmes , Testes de Sensibilidade Microbiana
15.
Materials (Basel) ; 17(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38612097

RESUMO

Nonmetallic ionic liquids (ILs) exhibit unique advantages in catalyzing poly (ethylene terephthalate) (PET) glycolysis, but usually require longer reaction times. We found that exposure to UV radiation can accelerate the glycolysis reaction and significantly reduce the reaction time. In this work, we synthesized five nonmetallic dibasic ILs, and their glycolysis catalytic activity was investigated. 1,8-diazabicyclo [5,4,0] undec-7-ene imidazole ([HDBU]Im) exhibited better catalytic performance. Meanwhile, UV radiation is used as a reinforcement method to improve the PET glycolysis efficiency. Under optimal conditions (5 g PET, 20 g ethylene glycol (EG), 0.25 g [HDBU]Im, 10,000 µW·cm-2 UV radiation reacted for 90 min at 185 °C), the PET conversion and BHET yield were 100% and 88.9%, respectively. Based on the UV-visible spectrum, it was found that UV radiation can activate the C=O in PET. Hence, the incorporation of UV radiation can considerably diminish the activation energy of the reaction, shortening the reaction time of PET degradation. Finally, a possible reaction mechanism of [HDBU]Im-catalyzed PET glycolysis under UV radiation was proposed.

16.
Angew Chem Int Ed Engl ; 52(47): 12350-3, 2013 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-24115399

RESUMO

Chemisorption of carbon dioxide by 1-ethyl-3-methylimidazolium acetate ([C2 mim][OAc]) provides a route to coagulate chitin and cellulose from [C2 mim][OAc] solutions without the use of high-boiling antisolvents (e.g., water or ethanol). The use of CO2 chemisorption as an alternative coagulating process has the potential to provide an economical and energy-efficient method for recycling the ionic liquid.


Assuntos
Dióxido de Carbono/química , Celulose/química , Quitina/química , Imidazóis/química , Líquidos Iônicos/química , Adsorção , Biomassa , Etanol/química , Soluções/química , Água/química
17.
Materials (Basel) ; 16(6)2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36984242

RESUMO

Compared with conventional pyrolysis, steam-assisted pyrolysis of polyethylene terephthalate (PET) can effectively eliminate char and upgrade terephthalic acid (TPA). However, during steam-assisted pyrolysis of PET, the degree of cracking still varies greatly, and while some of the product is excessively cracked to gas, the other part is still insufficiently cracked. In addition, these two types of products seriously affect the yield and purity of TPA. To further enhance the TPA, an attempt was made to reduce these impurities simultaneously by synergistic catalysis among the different components of the metal-acid catalyst. Through a series of experiments, Pt@Hzsm-5 was screened as the optimal catalyst. In the catalytic steam-assisted pyrolysis of PET, the optimum reaction temperature decreased to 400 °C, the calculated yield of TPA increased to 98.23 wt%, and the purity increased to 92.2%. The Pt@Hzsm-5 could be recycled three times with no significant decrease in the obtained yield of TPA. The catalytic mechanism of the Pt@Hzsm-5 was investigated through the analysis of the products and isotope tracing experiments. The Pt catalyzed the hydrogen transfer reaction between the water molecules and PET molecules, which inhibited the excessive cracking of TPA by improving the hydrogen transfer efficiency, reduced the generation of gaseous products, and improved the calculated yield of TPA. In contrast, the Hzsm-5 catalyzed the reaction of monovinyl ester cracking to TPA, effectively reducing the impurities in the solid product, increasing the olefin yield, and improving the purity of TPA. This discovery not only clarifies the synergistic catalytic effect of the Pt@Hzsm-5 in the steam-assisted pyrolysis of the PET reaction but also lays the foundation for further screening of other inexpensive metal-acid catalysts. This is of great significance to realize the industrial application of TPA preparation by PET pyrolysis.

18.
Bioresour Technol ; 383: 129178, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37270148

RESUMO

This study reported that surfactants could facilitate the organosolv pretreatment of lignocellulosic biomass (LCB) to produce fermentable sugars and highly active lignin. Under the optimized conditions, the surfactant-assisted glycerol organosolv (saGO) pretreatment achieved 80.7% delignification with a retention of 93.4% cellulose and 83.0% hemicellulose. The saGO pretreated substrate exhibited an excellent enzymatic hydrolyzability, achieving 93% of glucose yield from the enzymatic hydrolysis at 48 h. Structural analysis showed that the saGO lignin contained rich ß-O-4 bondings with less repolymerization and lower phenolic hydroxyl groups, thus forming highly reactive lignin fragments. The analysis evidenced that the surfactant graft the lignin by structural modification, which was responsible for the excellent substrate hydrolyzability. The co-production of fermentable sugars and organosolv lignin almost recovered a gross energy (87.2%) from LCB. Overall, the saGO pretreatment holds a lot of promise for launching a novel pathway towards lignocellulosic fractionation and lignin valorization.


Assuntos
Glicerol , Lignina , Açúcares , Tensoativos , Biomassa , Hidrólise
19.
Curr Med Sci ; 42(5): 1033-1045, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36260266

RESUMO

OBJECTIVE: MicroRNA (miRNA/miR)-633 is dysregulated in several types of cancers and is involved in tumorigenesis. However, the function and role of this miRNA in gastric cancer (GC) are not fully understood. The aim of the present study was to evaluate miR-633 expression in GC cell lines and in GC tissue vs. adjacent normal tissue, and to determine its association with clinicopathological data. This work was extended to investigate the effects of miR-633 overexpression on tumor cells in vitro. METHODS: Reverse transcription-quantitative PCR (RT-qPCR) was used to detect and compare the expression level of miR-633 in GC cells, as well as in GC and normal adjacent tissue samples. The clinical significance of miR-633 was also analyzed. MiR-633 lentivirus (LV-miR-633) and negative control lentivirus (LV-NC) were generated and used to transduce SGC-7901 and HGC-27 GC cells in order to analyze the effect of miR-633 on their phenotype. The effects of miR-633 overexpression on GC cell proliferation, apoptosis, migration and invasion were investigated. The target gene of miR-633 was predicted, then confirmed using a dual luciferase reporter gene assay, RT-qPCR and Western blotting. RESULTS: MiR-633 was significantly downregulated in GC cell lines, as well as in GC tissue compared with adjacent normal tissue. Moreover, miR-633 expression was associated with the tumor/node/metastasis (TNM) stage, invasion depth, Borrmann classification and lymph node metastasis (P<0.05). Compared with the LV-NC group, transduction with LV-miR-633 reduced the proliferation, the number of clones, the wound healing rate, the number of invading cells and the number of cells in the G1 phase of the cell cycle (P<0.01). LV-miR-633 also increased the apoptosis rate (P<0.01). The expression level of mitogen-activated protein kinase (MAPK) 1, high-mobility group box 3 (HMGB3), claudin 1 (CLDN1) and MAPK13 were downregulated in LV-miR-633-transduced cells (P<0.01). The dual luciferase reporter assay confirmed that the 3'-untranslated region of MAPK1 was the target site of miR-633 (P<0.01). CONCLUSION: MiR-633 acts as a tumor suppressor in GC, and its expression level is associated with TNM stage, invasion depth, Borrmann type and lymph node metastasis. Overexpression of miR-633 inhibits the proliferation and migration of GC cells and induces apoptosis and cell cycle arrest at the in G1 phase. In addition, miR-633 negatively regulates the expression of MAPK1, HMGB3, CLDN1 and MAPK13 and directly targets MAPK1.


Assuntos
MicroRNAs , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/metabolismo , Metástase Linfática , Invasividade Neoplásica/genética , Regulação Neoplásica da Expressão Gênica , Proliferação de Células/genética , Movimento Celular/genética , Claudina-1/genética , Claudina-1/metabolismo , Apoptose/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Regiões não Traduzidas , Proteína Quinase 1 Ativada por Mitógeno/metabolismo
20.
Int J Biol Macromol ; 181: 45-50, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-33766588

RESUMO

In recent years, various biomacromolecule-based hydrogels have been extensively and deeply studied in the field of wearable electronics. However, the application of lignin-based hydrogels in flexible devices is still in its infancy. This is mainly due to the significant differences in physical and chemical properties of industrially extracted lignin. In order to seek the universal applicability of diversified lignin in the preparation of hydrogel electronics, we mainly paid attention to the natural physical and chemical properties of lignin to discuss feasible solutions for functional gel design. These properties include chemical reactivity, UV shielding, antibacterial, bio-degradability, anti-oxidation, etc. Finally, in view of lignin's unique properties and the demand for high-quality flexible electronics, some insights are proposed regarding the future research and development directions of lignin-based hydrogel electronics.


Assuntos
Hidrogéis/química , Lignina/química , Dispositivos Eletrônicos Vestíveis , Catálise , Nanopartículas/química , Oxirredução
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