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Understanding the edulcorant profile of synthetic glucosyl steviol glycosides (GSGs) and rare natural steviol glycosides (SGs) is challenging due to their numerous species and rareness. This study developed a computational model based on the interactions of SG molecules with human sweet and bitter taste receptors (hSTR/hBTR). The models demonstrated a high correlation between the cumulative interaction energies and the perceived sweetness of SGs (R2 = 0.97), elucidating the mechanism of the diverse sweetness of SGs. It also revealed that more (within three) glucose residues at the C-13 position of the SG molecule yield stronger sweetness and weaker bitterness. Furthermore, the computational prediction was consistently validated with the known sweetness of GSG and also aligned well with that of several natural mogrosides. Thus, this model possesses a potential to predict the sweetness of SGs, GSGs, and mogrosides, facilitating the application or targeted synthesis of GSGs with desired sensory profiles.
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This paper offers a comprehensive overview of the polyhedral oligomeric silsesquioxane (POSS) and POSS-based composites within the realm of photoresist resin. The study involves a systematic exploration and discussion of the contributions made by POSS across various lithographic systems, with specific emphasis on critical parameters such as film formation, sensitivity, resolution, solubility, and edge roughness. These lithographic systems encompass X-ray lithography (XRL), deep ultraviolet nanoimprint lithography (DUV-NIL), extreme ultraviolet lithography (EUV), and guided self-assembled lithography (DSA). The principal objective of this paper is to furnish valuable insights into the development and utilization of POSS-based photoresist materials in diverse lithographic contexts.
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The ubiquitous contamination of surfactants in wastewater has raised global concerns. Photocatalysis is deemed as a promising yet challenging approach for the decomposition of surfactant residues. Herein, a novel Z-scheme heterojunction of Bi4O5Br2/Bi2S3 with covalent S-O bonds was prepared via a facile one-pot hydrothermal and subsequent annealing process. The prepared optimal Bi4O5Br2/Bi2S3 composite exhibited remarkable photo-degradation activity towards the sodium dodecylbenzene sulfonate (SDBS). The Z-scheme reaction mechanism was proposed and validated by meticulous analysis of quenching tests, ESR spectroscopy and DFT calculations. Furthermore, the presence of chemical S-O linkages between Bi4O5Br2 and Bi2S3 was identified via FT-IR and XPS analyses, which served as a distinct bridge to modify the Z-scheme route for carrier transport. The Z-scheme heterostructure, in conjunction with chemical S-O bonds, synergistically enhanced the separation rate of electron-hole pairs and thus greatly boosted the photocatalytic activity. Additionally, the possible degradation pathways of SDBS were proposed by using HR-MS technology. Moreover, real hotel laundry wastewater could be efficiently disposed by the photocatalysis of the Bi4O5Br2/Bi2S3 with a decrease in the COD value from 428 to 74 mg/L, indicating that the fabricated Z-scheme heterojunction hold great promise for effectively removing refractory surfactant contaminants from aquatic environment.
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Bencenosulfonatos , Surfactantes Pulmonares , Aguas Residuales , Espectroscopía Infrarroja por Transformada de Fourier , TensoactivosRESUMEN
Polyphenols from stevia leaves (PPSs) are abundant byproducts from steviol glycoside production, which have been often studied as raw extracts from stevia extracts for their bioactivities. Herein, the PPSs rich in isochlorogenic acids were studied for their antimicrobial and anti-inflammatory properties, as well as their inhibitory effects on digestive enzymes. The PPSs presented stronger antibacterial activity against E. coli, S. aureus, P. aeruginosa, and B. subtilis than their antifungal activity against M. furfur and A. niger. Meanwhile, the PPSs inhibited four cancer cells by more than 60% based on their viability, in a dose-dependent manner. The PPSs presented similar IC50 values on the inhibition of digestive enzyme activities compared to epigallocatechin gallate (EGCG), but had weaker anti-inflammatory activity. Therefore, PPSs could be a potential natural alternative to antimicrobial agents. This is the first report on the bioactivity of polyphenols from stevia rebaudiana (Bertoni) leaves excluding flavonoids, and will be of benefit for understanding the role of PPSs and their application.
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Diterpenos de Tipo Kaurano , Stevia , Polifenoles/farmacología , Escherichia coli , Staphylococcus aureus , Extractos Vegetales/farmacología , Antibacterianos/farmacología , Diterpenos de Tipo Kaurano/farmacología , Hojas de la PlantaRESUMEN
Au nanoparticles were synthesized in a soft template of pseudo-polyanions composed of polyvinylpyrrolidone (PVP) and sodium dodecyl sulfate (SDS) by the in situ reduction of chloroauric acid (HAuCl4) with PVP. The particle sizes and morphologies of the Au nanoparticles were regulated with concentrations of PVP or SDS at room temperature. Distinguished from the Au nanoparticles with various shapes, Au nanoflowers (AuNFs) with rich protrusion on the surface were obtained at the low final concentration of SDS and PVP. The typical AuNF synthesized in the PVP (50 g·L-1)-SDS (5 mmol·L-1)-HAuCl4 (0.25 mmol·L-1) solution exhibited a face-centered cubic structure dominated by a {111} crystal plane with an average equivalent particle size of 197 nm and an average protrusion height of 19 nm. Au nanoparticles with four different shapes, nanodendritic, nanoflower, 2D nanoflower, and nanoplate, were synthesized and used to modify the bare glassy carbon electrode (GCE) to obtain Au/GCEs, which were assigned as AuND/GCE, AuNF/GCE, 2D-AuNF/GCE, and AuNP/GCE, respectively. Electrochemical sensing platforms for nitrite detection were constructed by these Au/GCEs, which presented different detection sensitivity for nitrites. The results of cyclic voltammetry (CV) demonstrated that the AuNF/GCE exhibited the best detection sensitivity for nitrites, and the surface area of the AuNF/GCE was 1.838 times of the bare GCE, providing a linear c(NO2-) detection range of 0.01-5.00 µmol·L-1 with a limit of detection of 0.01 µmol·L-1. In addition, the AuNF/GCE exhibited good reproducibility, stability, and high anti-interference, providing potential for application in electrochemical sensing platforms.
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Nanopartículas del Metal , Nitritos , Nitritos/química , Oro/química , Nanopartículas del Metal/química , Reproducibilidad de los Resultados , Técnicas Electroquímicas/métodos , Carbono/química , Electrodos , Povidona/químicaRESUMEN
Reducing the recombination rate of photoexcited electron-hole pairs is always a great challenging work for the photocatalytic technique. In response to this issue, herein, a novel Z-scheme CuInS2/In2O3 with interfacial S-O linkages was synthesized by a hydrothermal and subsequently annealing method. The Fourier transform infrared (FT-IR) and X-ray photoelectron spectrometer (XPS) measurements confirmed the formation of covalent S-O bonds between CuInS2 and In2O3. The quenching and electron spin resonance (ESR) tests revealed the Z-scheme transfer route of photogenerated carriers over the CuInS2/In2O3 heterojunctions, which was further verified theoretically via density functional theory (DFT) calculations. As expected, the CuInS2/In2O3 heterojunctions showed significantly boosted photocatalytic activities for lomefloxacin degradation and Cr(vi) reduction under visible light illumination compared with the bare materials. Accordingly, a synergistic photocatalytic mechanism of Z-scheme heterostructures and interfacial S-O bonding was proposed, in which the S-O linkage could act as a specific bridge to modify the Z-scheme manner for accelerating the interfacial charge transmission. Furthermore, the CuInS2/In2O3 heterojunction also exhibited excellent performance perceived in the stability and reusability tests. This work provides a new approach for designing and fabricating novel Z-scheme heterostructures with a high-efficiency charge transfer route.
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Water pollution caused by the massive use of medicines has caused significant environmental problems. This work first reports the synthesis and characterization of the Cu7 S4 /CuCo2 O4 (CS/CCO) yolk-shell microspheres via hydrothermal and annealing methods, and then investigates their photocatalytic performance in removing organic water pollutants. The 10-CS/CCO composite with yolk-shell microspheres exhibits the highest photodegradation rate of carbamazepine (CBZ), reaching 96.3% within 2 h. The 10-CS/CCO also demonstrates more than two times higher photodegradation rates than the pure (Cu7 S4 ) CS and (CuCo2 O4 ) CCO. This outstanding photocatalytic performance can be attributed to the unique yolk-shell structure and the Z-scheme charge transfer pathway, reducing multiple reflections of the acting light. These factors enhance the light absorption efficiency and efficiently transfer photoexcited charge carriers. In-depth, photocatalytic degradation pathways of CBZ are systematically evaluated via the identification of degradation intermediates with Fukui index calculation. The insights gained from this work can serve as a guideline for developing low-cost and efficient Z-scheme photocatalyst composites with the yolk-shell structure.
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Cannabidiol (CBD) from Cannabis sativa is used in cosmetics in North America due to its antibacterial and antioxidant properties, but has been prohibited in many countries except recently; so, finding a non-intoxicating CBD alternative and elucidating the structure−function relationship of CBD analogues is becoming increasingly relevant. Herein, a set of CBD analogues including 8,9-dihydrocannabidiol (H2CBD) was synthesized, and their antibacterial, bactericidal, and antioxidant activity, as well as their structure−function relationship, were studied. The results present a catalytic selectivity near 100% towards H2CBD with a production yield of 85%. Each CBD analogue presented different antibacterial and antioxidant activity. It is revealed that the phenolic hydroxyl moiety is an essential group for CBD analogues to perform antibacterial and antioxidant activities. Among them, H2CBD presented much stronger antibacterial activity than the assayed popular antibiotics. H2CBD and Compound 4 presented very similar radical scavenging activity and inhibition on lipid oxidation to vitamin C, but better thermostability. Moreover, H2CBD presented lower toxicity to human skin fibroblasts at concentrations up to 64-fold higher than its MIC value (1.25 µg/mL) against S. aureus. Above all, in all property experiments, H2CBD presented extremely similar performance to CBD (p < 0.05), including similar time−kill kinetics curves. This research finds H2CBD to be an alternative for CBD with very high potential in the aspects of antibacterial, bactericidal, and antioxidant activity, as well as lower toxicity to human skin fibroblasts.
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Cannabidiol , Cannabis , Humanos , Cannabidiol/farmacología , Antioxidantes/farmacología , Staphylococcus aureus , Antibacterianos/farmacologíaRESUMEN
Assemblies of as called "chitosan hydrogel-liposome" are expected for overcoming the burst effect in drug release from chitosan (CS) hydrogels. Herein, a hydrogel delivery system made of chitosan incorporated fatty acid vesicles was constructed for protective sustained release of curcumin (Cur). The curcumin was encapsulated in the prepared oligo-conjugated linoleic acid vesicles (OCLAVs), and then the drug-embedded vesicles were constructed to Cur-OCLAVs-CS hydrogels with CS solution. The fabricated Cur-OCLAVs-CS hydrogel was fluidic at room temperature and could be rapidly gelled at 37 °C. Morphology study proves that the OCLAVs stayed as nano-vesicles in the gel. The Cur-OCLAVs-CS hydrogels effectively declined the burst effect with enhanced antioxidant activity. The Cur (400 µM)-OCLAVs-CS gel presented a cumulative release rate of 51.23 % of curcumin in 96 h, comparing to 93.37 % of that from the Cur-CS gel. Moreover, the corporation of OCLAVs and CS made the gel exhibited strong synergistic effect on the antioxidant activity, with an enhancement of up to 148.1 % on the ferric reducing power. Therefore, the hydrogel carrier made of incorporated fatty acid vesicles-chitosan can be served as an injectable or 3D printable drug delivery system, which may provide a hint to overcome the burst effect that existed in chitosan and other polysaccharide-based gels.
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Quitosano , Curcumina , Hidrogeles , Curcumina/farmacología , Ácido Linoleico , Preparaciones de Acción Retardada , Antioxidantes/farmacologíaRESUMEN
High-efficiency separation of photogenerated charges and molecular oxygen activation is very important for photocatalytic removal of organic pollutants. However, the current understanding of the effect mechanism of metal substitution for the separation of photo-generated charges and molecular oxygen activation is still poor. Herein, efficient manganese (Mn)-doped BiOBr hollow microspheres synthesis, systematic characterizations, and theoretical calculation discovered that Mn-doping could not only induce produce oxygen vacancies (OVs), but also can act as active sites for catalytic reactions. The induced production of OVs and Mn2+/Mn3+ by Mn optimal doping introduced into BiOBr can synergistic promote the separation of photogenerated charges and molecular oxygen activation leads to significantly enhances degradation of crystal violet (CV). Upon analysis, Mn-doping introducing unsaturated d-orbital with bridging O2- formation π-donation accelerated the separation of photo-generated charges. Meanwhile, the larger overlap of Mn-3d orbitals with O2-2p orbitals forms a π-donation bond with charge transfer from metal to O2 leading to the oxygen-oxygen (OO) bond length and molecular oxygen activation. Finally, we proposed a possible mechanism to explain the highly efficient photocatalytic degradation performance of the acquired photocatalysts. This study provides not only a novel strategy for the rational design of highly active photocatalysts, but also in-depth insights into the separation of photo-generated charges and molecular oxygen activation.
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Contaminantes Ambientales , Manganeso , Manganeso/química , Microesferas , Violeta de Genciana , Oxígeno/químicaRESUMEN
Selenium (Se)-enriched peptides were isolated from Cardamine violifolia by enzymatic hydrolysis and ultrafiltration. S3 (molecular weight [MW] distribution of 3-5 kDa) exhibited the strongest inhibitory effect on HepG2 cells and was thus screened using the 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide assay; it was found to have a high organic Se content. Its amino acid sequence was determined using HPLC-MS/MS. We then examined its ability to inhibit tumor cell proliferation and found that it arrested tumor cells in the S phase; moreover, it could induce cancer cell apoptosis. Following S3 treatment, we observed a decrease in mitochondrial membrane potential and an increase in cell calcium content. Upon S3 treatment at 60 µg/ml, the relative activities of caspase-3 and caspase-9 increased by 1.48 times and 2.17 times, and the contents of PI3K and AKT decreased from 2.05 ng/L and 1.95 ng/L to 0.71 ng/L and 0.50 ng/L, respectively, when compared with the control group. Transcriptomic analysis revealed significant changes in the PI3K-AKT pathway following S3 treatment. This study thus established a foundation for additional development of Se-enriched peptides from C. violifolia as a functional food. PRACTICAL APPLICATION: Cardamine violifolia is a Se-tolerant cruciferous plant that can metabolically transform inorganic Se into organic Se that exists in the form of a selenoprotein. Se-enriched peptide obtained by extraction and enzymolysis of selenoprotein, as an organic combination of organic Se and peptide, possess valuable biological activities. In this paper, the effect of Se-enriched peptides of C. violifolia on tumor cells was studied via cell experiments, and its mechanism was preliminarily discussed, which should provide a theoretical basis for developing functional foods containing C. violifolia.
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Cardamine , Selenio , Apoptosis , Cardamine/química , Proliferación Celular , Células Hep G2 , Humanos , Péptidos/metabolismo , Péptidos/farmacología , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Selenio/análisis , Espectrometría de Masas en TándemRESUMEN
Construction of Z-scheme heterostructure is an effective strategy to enhance the charge carriers' separation. However, successfully achieving this on the defect heterojunction to improve the photocatalytic activity remains challenging. This work successfully obtained sulfur vacancy in the ZnIn2S4/BiOBr (SZIS/BOB) heterojunction composites with S-O covalent bonding using a hydrothermal method. As a result, they exhibited superior photocatalytic and stability performance. The optimized SZIS/BOB-10 exhibited excellent rhodamine B degradation (95.2%) and chromium (VI) reduction (97.8%) within 100 min under visible light. The enhanced composites with S-vacancies, S-O bond, and internal electric field induced the Z-scheme charge transfer mechanism. We had verified this mechanism based on the surface photovoltage spectra, electron spin response spectra, and density functional theory calculations. This work not only provides valuable insights into designing photocatalysts with a direct Z scheme heterostructure but also delineates a promising strategy for developing efficient photocatalysts to degrade organic pollutants.
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Cromo , Agua , Bismuto , Programas InformáticosRESUMEN
Targeted radionuclide therapy (TRT) has been a promising strategy for cancer therapy, which can inhibit or kill cancer cells by selectively delivering radionuclide to target tissues. Herein, a legumain-targeted therapeutic agent [131I]MAAN was synthesized that was capable of condensation and self-assembly in response to legumain and glutathione (GSH) in tumor cells to enhance the therapeutic effect. This radiopharmaceutical has been acquired with a radiochemical yield (RCY) of 57.8 ± 5.3% and a high radiochemical purity (RCP) of more than 95%. In vitro cellular uptake assay suggested that [131I]MAAN had a 2-fold higher uptake in legumain-positive HCT116 cells than in the legumain-negative SKOV3 cells, revealing the specificity of the agent for legumain. Similarly, the in vitro cytotoxicity assay showed that [131I]MAAN possessed a more obvious killing effect on HCT116 cells. Cerenkov imaging with [131I]MAAN was carried out to generate clear tumor images. TRT with [131I]MAAN significantly inhibited the tumor growth and no obvious toxicity towards other normal organs was observed, indicating that it is a safe and effective treatment for cancers. Therefore, the agent [131I]MAAN holds great potential for the diagnosis and treatment of cancers with a high expression level of legumain.
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Cisteína Endopeptidasas , Radioisótopos de Yodo , Cisteína Endopeptidasas/metabolismo , Células HCT116 , HumanosRESUMEN
BACKGROUND: Unsaturated fatty acids used to form unstable micro-vesicles, while conjugate linoleic acid (CLA)-sodium dodecyl sulfate (SDS) can self-assembly to stable nano-conjugate linoleic acid vesicles (nano-CLAVs). Generally, micro-capsule could geometrically provide higher loading capacity but also generate concerns in construction convenience, sustained release, bioaccessibility and stability. Hence there is a contradiction between loading capacity and encapsulation efficiency. Therefore, the study of the factors that decide the capsule size falling in nano or micron size with same capsule material would be a benefit to food or drug delivery science. RESULTS: The micron- and nano-CLAVs were constructed for encapsulation and sustained release of ginsenoside Rg3. The formation mechanism of nano or micron capsule,s the effect of vesicle sizes on encapsulation efficiency, drug loading efficiency and stability of the encapsulated Rg3 were investigated. It was found that with the addition of salt (PBS), the size of CLAVs jumped from nano to micron. Furthermore, the salt concentration is the key factor that decides the vesicle size of nano or micron. The pH at fabrication triggers the vesiculation and dramatically affects the vesicle size over the nano and micron scales. CONCLUSION: Compared to the nano-CLAVs, micron vesicles enhanced the loading capacity to 137.6% and the encapsulation efficiency to 138.4%, respectively. Meanwhile, the micron-CLAVs performed similar sustained release of Rg3 as the nano-CLAVs did, and was stable for 120 days at room temperature or sustained 98.9% of capsules after centrifuge at 6090 × g for 20 min. © 2022 Society of Chemical Industry.
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Ginsenósidos , Ácidos Linoleicos Conjugados , Preparaciones de Acción Retardada , Sistemas de Liberación de MedicamentosRESUMEN
Polymeric Pickering emulsifiers may bring new insights to emulsion theory and practice due to their soft characters. Herein, a group of soft Pickering emulsifiers, chitosan-casein hydrophobic peptides nanoparticles (CS-CHP NPs) were prepared with a non-covalent anti-solvent procedure. The CS-CHP NPs provided the contact angles of 37.2°-87.4°, stabilizing O/W or W/O emulsions with enhanced thermal stability, endowing the emulsion with pH and CO2/N2 responsiveness. The emulsifying behavior and mechanism presented by CS-CHP NPs were different from that of ordinary hard Pickering emulsifiers, where the appropriate contact angle was 37.2° instead of 87.4° for stabilizing O/W emulsions. Moreover, the nanoparticles possess antioxidant, antibacterial activities and excellent biocompatibility. DPPH and ABTS scavenging activity of the CS-CHP NPs were >220% of that of CS NPs. The last, the emulsion provided high-efficient encapsulation of curcumin, making the soft Pickering emulsifiers a group candidate for drug delivery in food, cosmetics and pharmaceutical industry.
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Antibacterianos/farmacología , Antioxidantes/farmacología , Materiales Biocompatibles/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Antioxidantes/síntesis química , Antioxidantes/química , Benzotiazoles/antagonistas & inhibidores , Materiales Biocompatibles/síntesis química , Materiales Biocompatibles/química , Compuestos de Bifenilo/antagonistas & inhibidores , Caseínas/química , Caseínas/farmacología , Línea Celular , Quitosano/química , Quitosano/farmacología , Emulsiones , Escherichia coli/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Nanopartículas/química , Tamaño de la Partícula , Péptidos/química , Péptidos/farmacología , Picratos/antagonistas & inhibidores , Staphylococcus aureus/efectos de los fármacos , Ácidos Sulfónicos/antagonistas & inhibidoresRESUMEN
BACKGROUND: Rebaudioside A (RA) and its monoglucosyl derivative, as like rebaudioside D (RD) are the most popular stevia glycosides but possess poor solubility in water, which limited their application as edible surfactants, the applications as in micellar solubilization and drug delivery. Meanwhile, effect of the monoglucosyl attached to RA moiety remains unclear. RESULTS: Monoglucosyl rebaudioside A (RAG1) was synthesized via hydrolyzing the transglycosylation product of RA with 95% of RA converted. RAG1 content in raw reaction mixture was as high as 69.5% of total glycosides, and harvested with a content of 88.2% by simple filtration. The RAG1 exhibited an aqueous solubility of 87 folds of RA or 391 folds of RD at 25 °C. The surface activity of RAG1 solution was higher than RA and invincible to RD. The RAG1 micelles promoted aqueous solubility of idebenone (IDE) up to 500 folds higher at 25 °C. The cumulative release rate of IDE encapsulated in RAG1 micelles was 777.5% or 456.7% higher of that of free IDE in simulated gastric/intestinal fluids in 14 h, respectively. The RAG1-IDE remained the same in 98 days at 25 °C. CONCLUSION: The α-linked glucosyl to RA induced higher hydrophilicity and surface activity than that resulted by ß-linked glucosyl, making RAG1 not only dramatically raise the aqueous solubility of RA, but also endow IDE folds higher in bioaccessibility, yet making the capsule stable at storage. The results would provide a new edible delivery nanocarrier for encapsulation of hydrophobic bioactive components. © 2021 Society of Chemical Industry.
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Diterpenos de Tipo Kaurano , Stevia , Diterpenos de Tipo Kaurano/química , Aditivos Alimentarios , Glicósidos , Proteínas de Homeodominio , Micelas , Solubilidad , Stevia/químicaRESUMEN
Due to the poor lipophilicity of chlorogenic acid (CA), five CA derivatives (C2-CA, C4-CA, C6-CA, C8-CA, and C12-CA) with different lipophilicities were synthesized using acylation catalyzed by lipase in present study. The inhibitory activities and mechanisms of CA and its derivatives on α-amylase and α-glucosidase were then determined. Results showed that the inhibitory activities of CA derivatives on α-amylase and α-glucosidase were enhanced as lipophilicity increased, and the inhibitory activities of C12-CA were stronger than those of CA. IC50 values of C12-CA were 13.30 ± 0.26 µmol/mL for α-amylase and 3.42 ± 0.10 µmol/mL for α-glucosidase. C12-CA possessed the smallest Kic and Kiu values, and its inhibitory actions on α-amylase and α-glucosidase were stronger than those of CA and the other derivatives. Effects of C12-CA on microenvironments of amino acid residues and secondary structures of α-amylase and α-glucosidase were greater than those of CA and the other derivatives.
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alfa-Amilasas , alfa-Glucosidasas , Ácido Clorogénico , Inhibidores de Glicósido Hidrolasas , LipasaRESUMEN
In this study, chlorogenic acid (CA) was acylated with vinyl esters of different carbon chain lengths under the action of the lipase Lipozyme RM. Five CA derivatives (C2-CA, C4-CA, C6-CA, C8-CA, and C12-CA) with different lipophilicities were obtained, and their digestive stabilities and antioxidant activities were evaluated. The lipophilicities were positively correlated with the digestive stabilities of CA derivatives. The antioxidant activities of CA derivatives did not change with the reduction of phenolic hydroxyl groups, and their capacity to scavenge 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS+â¢) and 1,1-diphenyl-2-picrylhydrazyl (DPPHâ¢) were similar to those of CA. In cellular antioxidant activity (CAA) tests, it was found that the capacity of these derivates to cross cell membranes were enhanced upon enhancing lipophilicity, and their antioxidant activities were improved. C12-CA showed the best antioxidant activity with a median effective dose (EC50) of 9.40 µg/mL, which was significantly lower than that of CA (i.e., 29.08 µg/mL).
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The development of zinc-ion storage cathode materials for aqueous zinc-ion batteries (AZIBs) is a necessary step for the construction of large-scale electrochemical energy conversion and storage devices. Iron-doped alpha-manganese dioxide (α-MnO2) nanocomposites were achieved in this study via pre-intercalation of Fe3+ during the formation of α-MnO2 crystals. A polypyrrole (PPy) granular layer was fabricated on the surface of α-MnO2 using acid-catalyzed polymerization of pyrroles. The pre-intercalation of Fe3+ effectively enlarges the lattice spacing of α-MnO2 and consequently decreases the hindrance for Zn2+ insertion/extraction in the iron-doped α-MnO2 coated by PPy (Fe/α-MnO2@PPy) composite. Meanwhile, the PPy buffer layer can ameliorate electron and ion conductivity and prevent dissolution of α-MnO2during the charge/discharge process. This unique structure makes the Fe/α-MnO2@PPy composite an efficient zinc-ion storage cathode for AZIBs. The targeted Fe/α-MnO2@PPy cathode achieves superior performance with reversible specific capacity (270 mA h g-1 at 100 mA g-1) and exhibits highdiffusioncoefficientof 10-10-10-14 cm-2 s-1. Therefore, a feasible approach is implemented on advanced electrode materials using in AZIBs for practical applications.
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A superhydrophobic coating endows pristine hydrophilic wood with excellent water/moisture repellency and thus prolongs its service life. Generally, the superhydrophobic coating on wood is fabricated by a two-step process in which the nanoparticles are first introduced onto the surface and then modified by low-surface-energy molecules. Herein, for the first time, we have fabricated the superhydrophobic wood via a one-step process free of nanoparticles by immersing the pristine hydrophilic wood, such as pine, balsawood, and basswood, into a composite silane solution of hexadecyltrimethoxysilane and methyltrimethoxysilane. The wood remains superhydrophobic or highly hydrophobic after long-term exposure to mechanical damage (such as abrading, knife-cutting, and tape-peeling), chemical damage (such as immersion in acid, alkali, or ethanol), and environmental impacting (such as UV irradiation and low/high-temperature exposure).