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1.
J Sci Food Agric ; 104(3): 1668-1678, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37847204

RESUMO

BACKGROUND: Hemp protein isolates (HPIs), which provide a well-balanced profile of essential amino acids comparable to other high-quality proteins, have recently garnered significant attention. However, the underutilized functional attributes of HPIs have constrained their potential commercial applications within the food and agriculture field. This study advocates the utilization of dynamic-high-pressure-microfluidization (DHPM) for the production of stable high-internal-phase emulsions (HIPEs), offering an efficient approach to fully exploit the potential of HPI resources. RESULTS: The findings underscore the effectiveness of DHPM in producing HPI as a stabilizing agent for HIPEs with augmented antioxidant activity. Microfluidized HPI exhibited consistent adsorption and anchoring at the oil-water interface, resulting in the formation of a dense and compact layer. Concurrently, the compression of droplets within HIPEs gave rise to a polyhedral framework, conferring viscoelastic properties and a quasi-solid behavior to the emulsion. Remarkably, HIPEs stabilized by microfluidized HPI demonstrated superior oxidative and storage stability, attributable to the establishment of an antioxidative barrier by microfluidized HPI particles. CONCLUSION: This study presents an appealing approach for transforming liquid oils into solid-like fats using HPI particles, all without the need for surfactants. HIPEs stabilized by microfluidized HPI particles hold promise as emerging food ingredients for the development of emulsion-based formulations with enhanced oxidative stability, thereby finding application in the food and agricultural industries. © 2023 Society of Chemical Industry.


Assuntos
Cannabis , Emulsões/química , Excipientes , Oxirredução , Antioxidantes/metabolismo , Estresse Oxidativo , Tamanho da Partícula
2.
Food Funct ; 15(1): 96-109, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38047401

RESUMO

The pursuit of food-based alternatives to conventional therapies for ulcerative colitis (UC) demands immediate attention. In prior investigations, we synthesized WPI-stachyose conjugates through the Maillard reaction, identifying them as functional prebiotics. However, their impact on in vivo regulation of gut microbiota remains inadequately explored. To bridge this gap, we delved into the therapeutic effects and mechanisms of WPI-stachyose conjugates as prebiotic-functional components in C57BL/6J mice afflicted with dextran sodium sulfate (DSS)-induced UC. The treatment involving WPI-stachyose conjugates led to significant therapeutic advancements, evident in the reduction of pro-inflammatory cytokine levels and restoration of gut microbiota composition. Noticeable enhancements were observed in UC-associated symptoms, including weight loss, colon length reduction, and tissue damage, notably improving in the treated mice. Remarkably, both the conjugates and the physical combination effectively lowered pro-inflammatory cytokines and oxidative stress, with the conjugates demonstrating enhanced effectiveness. Furthermore, the simultaneous administration of WPI-stachyose conjugates further amplified the presence of beneficial bacteria and elevated short-chain fatty acids, acknowledged for their favorable impact across various conditions. These findings underscore the potential therapeutic application of WPI-stachyose conjugates in addressing DSS-induced UC, offering insights into innovative therapeutic strategies.


Assuntos
Colite Ulcerativa , Colite , Animais , Camundongos , Camundongos Endogâmicos C57BL , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Citocinas , Prebióticos , Sulfato de Dextrana , Modelos Animais de Doenças , Colo
3.
Materials (Basel) ; 16(17)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37687716

RESUMO

As a transfer member at the discontinuous place of vertical load, the deep beam has a complex stress mechanism and many influencing factors, such as compressive strength of concrete, shear span ratio, and reinforcement ratio. At the same time, the stress analysis principle of traditional shallow beams is no longer applicable to the design and calculation of deep-beam structure. The main purpose of this paper was to use the strut-and-tie model to analyze its stress mechanism, and to verify the applicability of the model. Nine high-strength concrete deep-beam specimens with longitudinal reinforcement with an anchor plate of the same size were tested by two-point concentrated loading method. The effects of shear span ratio (0.3, 0.6, and 0.9), longitudinal reinforcement ratio (0.67%, 1.05%, and 1.25%), horizontal reinforcement ratio (0.33%, 0.45%, and 0.50%), and stirrup reinforcement ratio (0.25%, 0.33%, and 0.50%) on the failure mode, deflection curve, characteristic load, crack width, steel bar, and concrete strain of the specimens were analyzed. The results showed that the failure mode of deep-beam specimens was diagonal compression failure. The normal section cracking load was about 15 to 20% of the ultimate load, and the inclined section cracking load was about 30~40% of the ultimate load. The shear span ratio increased from 0.3 to 0.9, and the bearing capacity decreased by 32.9%. When the longitudinal reinforcement ratio increased from 0.67% to 1.25%, the ultimate load increased by 42.6%. The shear span ratio and longitudinal reinforcement ratio have a significant effect on the bearing capacity of the high-strength concrete deep beams with longitudinal reinforcement with an anchor plate. The shear capacity of nine high-strength concrete deep-beam specimens with longitudinal reinforcement with an anchor plate was calculated by national standards, and the results were compared with the calculation results of the Tan-Tang model, the Tan-Cheng model, SSTM, and SSSTM. The analysis showed that the softened strut-and-tie model takes into account the softening effect of compressive concrete, and is a more accurate mechanical model, which can be applied to predict the shear capacity of high-strength concrete deep-beam members with longitudinal reinforcement with an anchor plate.

4.
J Sci Food Agric ; 103(5): 2544-2553, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36571448

RESUMO

BACKGROUND: The application of curcumin (CUR) in the food industry is limited by its instability, hydrophobicity and low bioavailability. Yeast cell protein (YCP) is a by-product of spent brewer's yeast, which has the potential to deliver bioactive substances. However, the environmental stresses such as pH, salt and heat treatment has restricted its application in the food industry. Maillard reaction as a non-enzymatic browning reaction can improve protein stability under environmental stress. RESULTS: The CUR was successfully encapsulated into the hydrophobic core of YCP/glycated YCP (GYCP) and enhanced by hydrogen bonding, resulting in static fluorescence quenching of YCP/GYCP. The average diameter and dispersibility of GYPC-CUR nanocomplex were significantly improved after glucose glycation (121.40 nm versus 139.70 nm). Moreover, the encapsulation capacity of CUR was not influenced by glucose glycation. The oxidative stability and bioaccessibility of CUR in nanocomplexes were increased compared with free CUR, especially complexed with GYCP conjugates. CONCLUSION: Steric hindrance provided by glucose conjugation improved the enviriomental stability, oxidative activity and bioaccessibility of CUR in nanocomplexes. Thus, glucose-glycated YCP has potential application as a delivery carrier for hydrophobic compounds in functional foods. © 2022 Society of Chemical Industry.


Assuntos
Antineoplásicos , Curcumina , Nanopartículas , Curcumina/química , Antioxidantes , Saccharomyces cerevisiae , Reação de Maillard , Antineoplásicos/química , Tamanho da Partícula , Nanopartículas/química
5.
Food Chem ; 368: 130651, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34392117

RESUMO

Bovine serum albumin (BSA) and BSA-glucose conjugates (GBSAⅠ and GBSAⅠI) with different extent of glycation were complexed with curcumin (CUR). The formation mechanism of BSA/GBSA-CUR complexes and the effect of glycation on their physicochemical properties were investigated. Fluorescence quenching and FTIR analysis indicated that the BSA/GBSA-CUR nanocomplexes were formed mainly by hydrophobic interactions. XRD analysis demonstrated that CUR was present in an amorphous state in the nanocomplexes. BSA with a greater extent of glycation (BSA < GBSAⅠ

Assuntos
Curcumina , Glicosilação , Interações Hidrofóbicas e Hidrofílicas , Soroalbumina Bovina
6.
ACS Appl Mater Interfaces ; 9(24): 20904-20912, 2017 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-28570814

RESUMO

In this work, we synthesized the one-dimensional nanostructure of zinc 5,10,15,20-tetra(4-pyridyl)-21H,23H-porphine (ZnTPyP) via a self-assembly technique. Using sodium dodecyl sulfate (SDS) as "soft template", the self-assembled ZnTPyP (SA-ZnTPyP) had the morphology of hexagonal nanoprisms with a uniform size (diameter of 100 nm). The SA-ZnTPyP exhibited remarkably different spectral properties compared to those of the original ZnTPyP. The as-prepared SA-ZnTPyP was used to modify glassy carbon electrodes (GCE), and the electrochemiluminescence (ECL) behaviors of the SA-ZnTPyP/GCE were investigated. The hydrophilic carbon dots (C-dots) could efficiently prevent the dissolution of SA-ZnTPyP in DMF containing 0.1 mol L-1 TBAP and, simultaneously, could accelerate electron transfer. Therefore, the enhanced ECL was realized by C-dots/SA-ZnTPyP/GCE by using H2O2 as co-reactant. This amplification of ECL was further studied by ECL spectroscopies and cyclic voltammetry, and the corresponding mechanism was proposed.

7.
Anal Chem ; 88(22): 11207-11212, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27750417

RESUMO

A simple and rapid photoelectrochemical (PEC) sensor was developed for the label-free detection of a phosphoprotein (α-casein) based on a zirconium based porphyrinic metal-organic framework (MOF), PCN-222, which exhibited an enhanced photocurrent response toward dopamine under the O2-saturated aqueous media. In this work, in terms of PEC measurements and cyclic voltammetry, the PEC behaviors of PCN-222 in aqueous media were thoroughly investigated for the first time. Additionally, in the virtue of the steric hindrance effect from the coordination of the phosphate groups and inorganic Zr-O clusters as binding sites in PCN-222, this biosensor showed high sensitivity for detecting α-casein and the limit of detection (LOD) was estimated to be 0.13 µg mL-1. Moreover, the proposed method provides a promising platform for clinic diagnostic and therapeutics.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Estruturas Metalorgânicas/química , Fosfoproteínas/análise , Processos Fotoquímicos , Porfirinas/química , Zircônio/química , Limite de Detecção , Oxigênio/química , Tamanho da Partícula , Propriedades de Superfície
8.
Nanoscale ; 8(22): 11649-57, 2016 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-27218308

RESUMO

A Zr-based metal-organic framework with zinc tetrakis(carboxyphenyl)-porphyrin (ZnTCPP) groups (MOF-525-Zn) was utilized to develop a novel electrochemiluminescence (ECL) biosensor for highly sensitive protein kinase activity assay. In this work, in terms of ECL measurements and cyclic voltammetry, the cathodic ECL behaviors of MOF-525-Zn in aqueous media were thoroughly investigated for the first time. The photoelectric active groups ZnTCPP on the MOF-525-Zn frameworks could promote the generation of singlet oxygen ((1)O2) via a series of electrochemical and chemical reactions, resulting in a strong and stable red irradiation at 634 nm. Additionally, the surfactant tetraoctylammonium bromide (TOAB) further facilitated dissolved oxygen to interact with the active sites ZnTCPP of MOF-525-Zn. Furthermore, the inorganic Zr-O clusters of MOF-525-Zn were simultaneously served as the recognition sites of phosphate groups. And then, an ultrasensitive ECL sensor was proposed for protein kinase A (PKA) activity detection with a linear range from 0.01 to 20 U mL(-1) and a sensitive detection limit of 0.005 U mL(-1). This biosensor can also be applied for quantitative kinase inhibitor screening. Finally, it exhibits good performance with high stability and acceptable fabrication reproducibility, which provide a valuable strategy for clinic diagnostics and therapeutics.


Assuntos
Técnicas Biossensoriais , Metaloporfirinas/química , Proteínas Quinases/metabolismo , Zircônio/química , Elétrons , Oxigênio , Reprodutibilidade dos Testes
9.
Anal Chem ; 87(17): 9093-100, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26259126

RESUMO

Novel multifunctional magnetic zirconium hexacyanoferrate nanoparticles (ZrHCF MNPs) were prepared, which consisted of magnetic beads (MBs) inner core and zirconium hexacyanoferrate(II) (ZrHCF) outer shell. As an artificial peroxidase, the ZrHCF MNPs exhibited remarkable electrocatalytic properties in the reduction of H2O2 at 0.2 V vs saturated calomel electrode (SCE). On the basis of the bonding interaction between Zr (IV) of the shell ZrHCF framework and phosphonate groups, the 5'-phosphorylated ssDNA probes with a consecutive stretch of guanines as a spacer could be incorporated in ZrHCF MNPs easily. Thus, DNA-grafted ZrHCF MNPs could be simply obtained by magnetic separation. The prepared nanoelectrocatalyst was further used as signal nanoprobe for the ultrasensitive electrochemical DNA assay. Under optimal conditions, the proposed biosensor presents high sensitivity for detecting target DNA with a linear range from 1.0 fM to 1.0 nM and a low detection limit of 0.43 fM. Moreover, it exhibits good performance with excellent selectivity, high stability, and acceptable fabrication reproducibility.


Assuntos
DNA/análise , Técnicas Eletroquímicas , Ferrocianetos/química , Nanopartículas de Magnetita/química , Compostos Organometálicos/química , Zircônio/química , Tamanho da Partícula , Propriedades de Superfície
10.
Anal Biochem ; 460: 16-21, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-24887416

RESUMO

A novel self-assembled glucose biosensor based on graphene oxide (GO) was constructed by using 1-pyrenebutyric acid-N-hydroxysuccinimide ester (PANHS) as linking molecular. The stepwise self-assembly process was performed for PANHS anchoring in N,N-dimethylformamide (DMF) solvent and the further glucose oxidase (GOD) binding in aqueous solution, respectively. The molecular interactions and the morphologic properties were characterized by Fourier transform infrared spectroscopy (FTIR), field emission scanning electronic microscopy (FESEM), and atomic force microscopy (AFM). In addition, the quantitative loadings of anchored PANHS and GOD were well elucidated by surface plasmon resonance (SPR) measurements. The obtained novel glucose sensor exhibited satisfactory analytical performance to glucose: wide linear range (4.0×10(-6) to 4.4×10(-3) M), fast response (10s), high sensitivity (40.5±0.4 mA M(-1) cm(-2)), and low detection limit (2 µM, S/N=3). Furthermore, the biosensor exhibited excellent long-term stability and satisfactory reproducibility.


Assuntos
Glucose Oxidase/metabolismo , Grafite/química , Óxidos/química , Ressonância de Plasmônio de Superfície/métodos , Aspergillus niger/enzimologia , Dimetilformamida/química , Eletrodos , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Glucose/análise , Glucose Oxidase/química , Limite de Detecção , Platina/química , Pirenos/química , Reprodutibilidade dos Testes , Solventes/química , Succinimidas/química , Ressonância de Plasmônio de Superfície/instrumentação
11.
Environ Toxicol ; 29(12): 1437-51, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23776099

RESUMO

Benzene-induced erythropoietic depression has been proposed to be due to the production of toxic metabolites. Presently, the cytotoxicities of benzene metabolites, including phenol, catechol, hydroquinone, and 1,2,4-benzenetriol, to erythroid progenitor-like K562 cells were investigated. After exposure to these metabolites, K562 cells showed significant inhibition of viability and apoptotic characteristics. Each metabolite caused a significant increase in activities of caspase-3, -8, and -9, and pretreatment with caspase-3, -8, and -9 inhibitors significantly inhibited benzene metabolites-induced phosphatidylserine exposure. These metabolites also elevated expression of Fas and FasL on the cell surface. After exposure to benzene metabolites, K562 cells showed an increase in reactive oxygen species level, and pretreatment with N-acetyl-l-cysteine significantly protected against the cytotoxicity of each metabolite. Interestingly, the control K562 cells and the phenol-exposed cells aggregated together, but the cells exposed to other metabolites were scattered. Further analysis showed that hydroquione, catechol, and 1,2,4-benzenetriol induced a decrease in the cell surface sialic acid levels and an increase in the cell surface sialidase activity, but phenol did not cause any changes in sialic acid levels and sialidase activity. Consistently, an increase in expression level of sialidase Neu3 mRNA and a decrease in mRNA level of sialyltransferase ST3GAL3 gene were detected in hydroquione-, catechol-, or 1,2,4-benzenetriol-treated cells, but no change in mRNA levels of two genes were found in phenol-treated cells. In conclusion, these benzene metabolites could induce apoptosis of K562 cells mainly through caspase-8-dependent pathway and ROS production, and sialic acid metabolism might play a role in the apoptotic process.


Assuntos
Derivados de Benzeno/toxicidade , Caspases/metabolismo , Ácidos Siálicos/metabolismo , Apoptose , Catecóis/toxicidade , Membrana Celular/metabolismo , Humanos , Hidroquinonas/toxicidade , Células K562 , Fenol/toxicidade , Espécies Reativas de Oxigênio/metabolismo
12.
Toxicol Appl Pharmacol ; 265(1): 43-50, 2012 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23022512

RESUMO

Catechol is one of phenolic metabolites of benzene in vivo. Catechol is also widely used in pharmaceutical and chemical industries. In addition, fruits, vegetables and cigarette smoke also contain catechol. Our precious study showed that several benzene metabolites (phenol, hydroquinone, and 1,2,4-benzenetriol) inhibited erythroid differentiation of K562 cells. In present study, the effect of catechol on erythroid differentiation of K562 cells was investigated. Moreover, to address the role of DNA methylation in catechol-induced effect on erythroid differentiation in K562 cells, methylation levels of erythroid-specific genes were analyzed by Quantitative MassARRAY methylation analysis platform. Benzidine staining showed that exposure to catechol enhanced hemin-induced hemoglobin accumulation in K562 cells in concentration- and time-dependent manners. The mRNA expression of erythroid specific genes, including α-globin, ß-globin, γ-globin, erythroid 5-aminolevulinate synthase, erythroid porphobilinogen deaminase, and transcription factor GATA-1 genes, showed a significant concentration-dependent increase in catechol-treated K562 cells. The exposure to catechol caused a decrease in DNA methylation levels at a few CpG sites in some erythroid specific genes including α-globin, ß-globin and erythroid porphobilinogen deaminase genes. These results indicated that catechol improved erythroid differentiation potency of K562 cells at least partly via up-regulating transcription of some erythroid related genes, and suggested that inhibition of DNA methylation might be involved in up-regulated expression of some erythroid related genes.


Assuntos
Catecóis/farmacologia , Diferenciação Celular/efeitos dos fármacos , Metilação de DNA , Células Eritroides/efeitos dos fármacos , Diferenciação Celular/genética , Sobrevivência Celular/efeitos dos fármacos , Ilhas de CpG/efeitos dos fármacos , Hemina/farmacologia , Hemoglobinas/biossíntese , Hemoglobinas/metabolismo , Humanos , Células K562 , Família Multigênica , Reação em Cadeia da Polimerase , Regulação para Cima/efeitos dos fármacos
13.
Oral Oncol ; 43(9): 898-904, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17306607

RESUMO

Down-regulation of Cx43 expression had been shown to occur in nasopharyngeal carcinoma cells. The present study was undertaken to estimate if methylation of the promoter region in Cx43 gene was responsible for the repression of Cx43 expression in the CNE-1 nasopharyngeal carcinoma cells. Calcein transfer and lucifer yellow transfer were detected to evaluate gap junction intercellular communication (GJIC) in CNE-1 cells. It was found that the control CNE-1 cells showed no fluorescent dye transfer. After treatment with DNA methyltransferase inhibitor 5-aza-CdR, fluorescent dye transfer between cells became obvious. RT-PCR and Western blot were performed to determine the expression of Cx43 gene. The control CNE-1 cells showed a low expression level of Cx43, whereas 5-aza-CdR-treated CNE-1 cells showed an enhanced level of Cx43 expression. Methylation-sensitive restriction enzyme and PCR analysis showed that the methylation of the Cx43 gene promoter region occurred in CNE-1 cells. In addition, treatment with 5-aza-CdR inhibited the growth (including anchorage-independent growth) of CNE-1 cells, and resulted in an accumulation of cells in G0/G1 phase. These results indicate the promoter methylation as an important role in inactivation of Cx43 in CNE-1 cells.


Assuntos
Carcinoma de Células Escamosas/genética , Conexina 43/genética , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Neoplasias Nasofaríngeas/genética , Regiões Promotoras Genéticas , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Ciclo Celular , Linhagem Celular Tumoral , Metilação de DNA , Metilases de Modificação do DNA/antagonistas & inibidores , Decitabina , Fluoresceínas/metabolismo , Junções Comunicantes/metabolismo , Humanos , Isoquinolinas/metabolismo , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/patologia
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