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1.
PLoS One ; 19(7): e0306142, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38954698

RESUMO

Developing T1-weighted magnetic resonance imaging (MRI) contrast agents with enhanced biocompatibility and targeting capabilities is crucial owing to concerns over current agents' potential toxicity and suboptimal performance. Drawing inspiration from "biomimetic camouflage," we isolated cell membranes (CMs) from human glioblastoma (T98G) cell lines via the extrusion method to facilitate homotypic glioma targeting. At an 8:1 mass ratio of ferric chloride hexahydrate to gallic acid (GA), the resulting iron (Fe)-GA nanoparticles (NPs) proved effective as a T1-weighted MRI contrast agent. T98G CM-coated Fe-GA NPs demonstrated improved homotypic glioma targeting, validated through Prussian blue staining and in vitro MRI. This biomimetic camouflage strategy holds promise for the development of targeted theranostic agents in a safe and effective manner.


Assuntos
Meios de Contraste , Ácido Gálico , Imageamento por Ressonância Magnética , Ácido Gálico/química , Humanos , Imageamento por Ressonância Magnética/métodos , Linhagem Celular Tumoral , Meios de Contraste/química , Ferro/química , Materiais Biomiméticos/química , Glioblastoma/tratamento farmacológico , Glioblastoma/diagnóstico por imagem , Glioblastoma/patologia , Nanopartículas/química , Compostos Férricos/química , Membrana Celular/metabolismo
2.
Food Res Int ; 190: 114632, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38945622

RESUMO

To improve the color stability of anthocyanins (ACNs) in blueberry fermented beverage, the intermolecular copigmentation between ACNs and 3 different phenolic compounds, including (-)-epigallocatechin gallate (EGCG), ferulic acid (FA), and gallic acid (GA) as copigments, was compared in the model and the real blueberry fermented beverage, respectively. The copigmented ACNs by EGCG presented a high absorbance (0.34 a.u.) and redness (27.09 ± 0.17) in the model blueberry fermented beverage. The copigmentation by the participation of the 3 different phenolic compounds showed all a spontaneous exothermic reaction, and the Gibbs free energy (ΔG°) of the system was lowest (-5.90 kJ/mol) using EGCG as copigment. Furthermore, the molecular docking model verified that binary complexes formed between ACNs and copigments by hydrogen bonds and π-π stacking. There was a high absorbance (1.02 a.u.), percentage polymeric color (PC%, 68.3 %), and good color saturation (C*ab, 43.28) in the real blueberry fermented beverage aged for 90 days, and more malvidin-3-O-glucoside had been preserved in the wine using EGCG as copigment. This finding may guide future industrial production of blueberry fermented beverage with improved color.


Assuntos
Antocianinas , Mirtilos Azuis (Planta) , Cor , Ácidos Cumáricos , Fermentação , Ácido Gálico , Simulação de Acoplamento Molecular , Fenóis , Antocianinas/química , Mirtilos Azuis (Planta)/química , Ácidos Cumáricos/química , Ácido Gálico/química , Ácido Gálico/análogos & derivados , Fenóis/análise , Fenóis/química , Catequina/química , Catequina/análogos & derivados , Sucos de Frutas e Vegetais/análise , Frutas/química
3.
Int J Biol Macromol ; 273(Pt 2): 133175, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38889835

RESUMO

The molecular and colloidal-level interactions between two major phenolic acids, gallic and caffeic acid, with a major food polysaccharide, xanthan gum, were studied in binary systems aiming to correlate the stability of the binary systems as a function of pH and xanthan-polyphenol concentrations. Global stability diagrams were built, acting as roadmaps for examining the phase separation regimes followed by the fluorimetry-based thermodynamics of the interactions. The effects of noncovalent interactions on the macroscopic behavior of the binary systems were studied, using shear and extensional rheometry. The collected data for caffeic acid - xanthan gum mixtures showed that the main interactions were pH-independent volume exclusions, while gallic acid interacts with xanthan gum, especially at pH 7 with other mechanisms as well, improving the colloidal dispersion stability. A combination of fluorimetry, extensional rheology and stability measurements highlight the effect of gallic acid-induced aggregation of xanthan gum, both in structuring and de-structuring the binary systems. The above provide a coherent framework of the physicochemical aspect of binary systems, shedding light on the role of xanthan gum in its oral functions, such as in inducing texture, in model complex systems containing phenolic acids.


Assuntos
Polissacarídeos Bacterianos , Reologia , Polissacarídeos Bacterianos/química , Hidroxibenzoatos/química , Concentração de Íons de Hidrogênio , Ácido Gálico/química , Termodinâmica
4.
Molecules ; 29(12)2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38930827

RESUMO

The content of chemical constituents in Eugenia uniflora leaf extracts correlates positively with biological activities. The experimental objective was to carry out the phytochemical screening and purification of the major polyphenols from the leaves of E. uniflora. In addition, the anti-Candida activity of the hydroalcoholic extract, fraction, subfractions and polyphenols purified were evaluated. After partitioning of the extract with ethyl acetate, the fractions were chromatographed on Sephadex® LH-20 gel followed by RP-flash chromatography and monitored by TLC and RP-HPLC. The samples were characterized by mass spectrometry (LC-ESI-QTOF-MS2) and subjected to the microdilution method in 96-well plates against strains of C. albicans, C. auris, and C. glabrata. Myricitrin (93.89%; w/w; m/z 463.0876), gallic acid (99.9%; w/w; m/z 169.0142), and ellagic acid (94.2%; w/w; m/z 300.9988) were recovered. The polyphenolic fraction (62.67% (w/w) myricitrin) and the ellagic fraction (67.86% (w/w) ellagic acid) showed the best antifungal performance (MIC between 62.50 and 500 µg/mL), suggesting an association between the majority constituents and the antifungal response of E. uniflora derivatives. However, there is a clear dependence on the presence of the complex chemical mixture. In conclusion, chromatographic strategies were effectively employed to recover the major polyphenols from the leaves of the species.


Assuntos
Antifúngicos , Eugenia , Extratos Vegetais , Folhas de Planta , Polifenóis , Polifenóis/farmacologia , Polifenóis/química , Polifenóis/isolamento & purificação , Eugenia/química , Folhas de Planta/química , Antifúngicos/farmacologia , Antifúngicos/química , Antifúngicos/isolamento & purificação , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Testes de Sensibilidade Microbiana , Candida/efeitos dos fármacos , Espectrometria de Massas em Tandem/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Cromatografia Líquida de Alta Pressão/métodos , Ácido Gálico/farmacologia , Ácido Gálico/química
5.
Nano Lett ; 24(26): 8179-8188, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38885447

RESUMO

The unique "Iron Addiction" feature of cancer stem cells (CSCs) with tumorigenicity and plasticity generally contributes to the tumor recurrence and metastasis after a lumpectomy. Herein, a novel "Ferroptosis Amplification" strategy is developed based on integrating gallic acid-modified FeOOH (GFP) and gallocyanine into Pluronic F-127 (F127) and carboxylated chitosan (CC)-based hydrogel for CSCs eradication. This "Ferroptosis Amplifier" hydrogel is thermally sensitive and achieves rapid gelation at the postsurgical wound in a breast tumor model. Specifically, gallocyanine, as the Dickkopf-1 (DKK1) inhibitor, can decrease the expression of SLC7A11 and GPX4 and synergistically induce ferroptosis of CSCs with GFP. Encouragingly, it is found that this combination suppresses the migratory and invasive capability of cancer cells via the downregulation of matrix metalloproteinase 7 (MMP7). The in vivo results further confirm that this "Ferroptosis Amplification" strategy is efficient in preventing tumor relapse and lung metastasis, manifesting an effective and promising postsurgical treatment for breast cancer.


Assuntos
Neoplasias da Mama , Ferroptose , Hidrogéis , Células-Tronco Neoplásicas , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Hidrogéis/química , Humanos , Animais , Neoplasias da Mama/patologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Feminino , Camundongos , Ferroptose/efeitos dos fármacos , Linhagem Celular Tumoral , Poloxâmero/química , Poloxâmero/farmacologia , Quitosana/química , Quitosana/farmacologia , Quitosana/análogos & derivados , Ácido Gálico/farmacologia , Ácido Gálico/química , Ácido Gálico/uso terapêutico
6.
J Mater Chem B ; 12(26): 6424-6441, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38860306

RESUMO

Gallic acid (GA), derived from land plants, possesses diverse physiological benefits, including anti-inflammatory and anticancer effects, making it valuable for biomedical applications. In this study, GA was used to modify the surface of dendritic mesoporous silica nanoparticles (DMSNs) via carbamate (DMSN-NCO-GA) or amide (DMSN-NH-GA) bonds, using a post-grafting technique. To explore GA-conjugated materials' potential in modulating cancer cell redox status, three variants of osteosarcoma cells (U2-OS) were used. These variants comprised the wild-type cells (NEO), the cells overexpressing the wild-type human Golgi anti-apoptotic protein (hGAAP), and the null mutant of hGAAP (Ct-mut), as this protein was previously demonstrated to play a role in intracellular reactive oxygen species (ROS) accumulation and cell migration. In the absence of external ROS triggers, non-modified DMSNs increased intracellular ROS in Ct-mut and NEO cells, while GA-conjugated materials, particularly DMSN-NH-GA, significantly reduced ROS levels, especially pronounced with higher GA concentrations and notably in hGAAP cells with inherently higher ROS levels. Additionaly, NH-GA conjugates were less cytotoxic, more effective in reducing cell migration, and had higher ROS buffering capacity compared to DMSN-NCO-GA materials. However, in the presence of the external stressor tert-butyl-hydroperoxide (TBHP), NCO-GA conjugates showed more efficient reduction of intracellular ROS. These findings suggest that varying chemical decoration strategies of nanomaterials, along with the accessibility of functional groups to the cellular environment, significantly influence the biological response in osteosarcoma cells. Highlighting this, GA-conjugation is a promising method for implementing antioxidant properties and inhibiting cancer cell migration, warranting further research in anticancer treatment and drug development.


Assuntos
Sequestradores de Radicais Livres , Ácido Gálico , Nanopartículas , Osteossarcoma , Dióxido de Silício , Humanos , Ácido Gálico/química , Ácido Gálico/farmacologia , Nanopartículas/química , Osteossarcoma/tratamento farmacológico , Osteossarcoma/patologia , Dióxido de Silício/química , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Propriedades de Superfície , Tamanho da Partícula , Ensaios de Seleção de Medicamentos Antitumorais , Sobrevivência Celular/efeitos dos fármacos , Linhagem Celular Tumoral
7.
ACS Appl Mater Interfaces ; 16(27): 34467-34479, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38936818

RESUMO

Myocardial cardiopathy is one of the highest disease burdens worldwide. The damaged myocardium has little intrinsic repair ability, and as a result, the distorted muscle loses strength for contraction, producing arrhythmias and fainting, and entails a high risk of sudden death. Permanent implantable conductive hydrogels that can restore contraction strength and conductivity appear to be promising candidates for myocardium functional recovery. In this work, we present a printable cardiac hydrogel that can exert functional effects on networks of cardiac myocytes. The hydrogel matrix was designed from poly(vinyl alcohol) (PVA) dynamically cross-linked with gallic acid (GA) and the conductive polymer poly(3,4-ethylenedioxythiophene) (PEDOT). The resulting patches exhibited excellent electrical conductivity, elasticity, and mechanical and contractile strengths, which are critical parameters for reinforcing weakened cardiac contraction and impulse propagation. Furthermore, the PVA-GA/PEDOT blend is suitable for direct ink writing via a melting extrusion. As a proof of concept, we have proven the efficiency of the patches in propagating the electrical signal in adult mouse cardiomyocytes through in vitro recordings of intracellular Ca2+ transients during cell stimulation. Finally, the patches were implanted in healthy mouse hearts to demonstrate their accommodation and biocompatibility. Magnetic resonance imaging revealed that the implants did not affect the essential functional parameters after 2 weeks, thus showing great potential for treating cardiomyopathies.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes , Condutividade Elétrica , Hidrogéis , Miócitos Cardíacos , Polímeros , Animais , Camundongos , Compostos Bicíclicos Heterocíclicos com Pontes/química , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Polímeros/química , Polímeros/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/citologia , Hidrogéis/química , Hidrogéis/farmacologia , Álcool de Polivinil/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Ácido Gálico/química , Ácido Gálico/farmacologia
8.
Biofouling ; 40(5-6): 348-365, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38836472

RESUMO

Our research focuses on developing environmentally friendly biodegradable ultrafiltration (UF) membranes for small-scale water purification in areas lacking infrastructure or during emergencies. To address biofouling challenges without resorting to harmful chemicals, we incorporate bio-based extracts, such as methyl gallate from A. occidentale leaves, a Malaysian ulam herb, known for its quorum sensing inhibition (QSI) properties. The methyl gallate enriched extract was purified by solvent partitioning and integrated into cellulose-based UF membranes (0 to 7.5% w w-1) through phase inversion technique. The resulting membranes exhibited enhanced anti-organic fouling and anti-biofouling properties, with flux recovery ratio (FRR) of 87.84 ± 2.00% against bovine serum albumin and FRRs of 76.67 ± 1.89% and 69.57 ± 1.77% against E. coli and S. aureus, respectively. The CA/MG-5 membrane showed a 224% improvement in pure water flux (PWF) compared to the neat CA membrane. Our innovative approach significantly improves PWF, presenting an environmentally friendly method for biofouling prevention in UF membrane applications.


Assuntos
Anacardium , Incrustação Biológica , Escherichia coli , Membranas Artificiais , Extratos Vegetais , Ultrafiltração , Purificação da Água , Incrustação Biológica/prevenção & controle , Ultrafiltração/métodos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Escherichia coli/efeitos dos fármacos , Anacardium/química , Purificação da Água/métodos , Staphylococcus aureus/efeitos dos fármacos , Ácido Gálico/análogos & derivados , Ácido Gálico/farmacologia , Ácido Gálico/química , Soroalbumina Bovina/química
9.
Biomacromolecules ; 25(7): 4358-4373, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38924782

RESUMO

Chitosan (CS)-based photo-cross-linkable hydrogels have gained increasing attention in biomedical applications. In this study, we grafted CS with gallic acid (GA) by carbodiimide chemistry to prepare the GA-CS conjugate, which was subsequently modified with methacrylic anhydride (MA) modification to obtain the methacrylated GA-CS conjugate (GA-CS-MA). Our results demonstrated that the GA-CS-MA hydrogel not only exhibited improved physicochemical properties but also showed antibacterial, antioxidative, and anti-inflammatory capacity. It showed moderate antibacterial activity and especially showed a more powerful inhibitory effect against Gram-positive bacteria. It modulated macrophage polarization, downregulated pro-inflammatory gene expression, upregulated anti-inflammatory gene expression, and significantly reduced reactive oxygen species (ROS) and nitric oxide (NO) production under lipopolysaccharide (LPS) stimulation. Subcutaneously implanted GA-CS-MA hydrogels induced significantly lower inflammatory responses, as evidenced by less inflammatory cell infiltration, thinner fibrous capsule, and predominately promoted M2 polarization. This study provides a feasible strategy to prepare CS-based photo-cross-linkable hydrogels with improved physicochemical properties for biomedical applications.


Assuntos
Antibacterianos , Anti-Inflamatórios , Antioxidantes , Quitosana , Ácido Gálico , Hidrogéis , Metacrilatos , Quitosana/química , Ácido Gálico/química , Ácido Gálico/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Animais , Hidrogéis/química , Hidrogéis/farmacologia , Hidrogéis/síntese química , Camundongos , Antioxidantes/química , Antioxidantes/farmacologia , Antioxidantes/síntese química , Metacrilatos/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Células RAW 264.7 , Reagentes de Ligações Cruzadas/química , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Óxido Nítrico/metabolismo
10.
Food Chem ; 455: 139865, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38823133

RESUMO

The aim of this research was to graft gallic acid (GA) onto high methoxyl pectin (HMP) through the redox-pair of ascorbic acid (Aa) and hydrogen peroxide (H2O2) with one- and two-pot procedures. The effectiveness of the both procedures and the chemical, physical and antioxidant properties of the obtained HMP-GA were evaluated. HMP-GAone-pot (23.3 ± 0.21 mg GA Equivalent (GAE)/g) and HMP-GAtwo-pot (32.3 ± 0.52 mg GAE/g) were best obtained at H2O2/Aa molar ratio-HMP/GA weight ratio of 9.0-0.5 and 16.0-0.5, respectively. The UV-Vis and FT-IR spectra and along with their derivative and thermal gravimetric analyses, revealed differences between HMP-GAone-pot and HMP-GAtwo-pot. The latter exhibited a greater antioxidant capacity than the former in single electron transfer (ET), hydrogen atom transfer (HAT), and ET-HAT mixed assays. The chemical differences can be attributed to side reactions that may have interfered with the grafting reaction. Consequently, HMP-GA, possessing unique antioxidant and prebiotic properties, can be synthesized through redox-pair procedures.


Assuntos
Antioxidantes , Ácido Gálico , Peróxido de Hidrogênio , Oxirredução , Pectinas , Pectinas/química , Ácido Gálico/química , Antioxidantes/química , Peróxido de Hidrogênio/química , Espectroscopia de Infravermelho com Transformada de Fourier , Ácido Ascórbico/química
11.
Int J Biol Macromol ; 272(Pt 1): 132808, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38825278

RESUMO

Cellulose nanocrystals (CNCs) have received increasing attention because of their superior dispersion and thermal stability. In this study, TEMPO-oxidized cellulose nanocrystal (TOCNC) multifunctional antioxidationantioxidation films (TOCNC-GA film) were prepared by the esterification of TOCNC and gallic acid (GA). TOCNC-GAX films, where X represents the ratio of the amount of GA to the amount of TOCNC, were characterized using scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The films with the GA:TOCNC ratio of 1:1 achieved higher interfacial compatibility than the other films. The mechanical properties and water resistance of the TOCNC-GA films were superior than those of pure TOCNC films. Moreover, the original TOCNC structure changed owing to the presence of GA, which endowed a certain thermoplasticity owing to the formation of ester groups. The antioxidation properties of the TOCNC-GA1 films reached 43.8 % and 71.85 % after 6 and 24 h, respectively, as evaluated by the 2,2-biphenyl-1-picrylhydrazyl method and the free radical scavenging activities of the TOCNC-GA1 films. The innovative development of the functional antioxidation film presented in this paper has great potential for use in antioxidation packaging materials and food preservation.


Assuntos
Antioxidantes , Celulose , Ácido Gálico , Nanopartículas , Esterificação , Antioxidantes/química , Antioxidantes/farmacologia , Celulose/química , Ácido Gálico/química , Nanopartículas/química , Óxidos N-Cíclicos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Oxirredução , Química Verde
12.
PLoS One ; 19(6): e0299372, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38885237

RESUMO

Phenolic acids still gain significant attention due to their potential antimicrobial and cytotoxic properties. In this study, we have investigated the antimicrobial of six phenolic acids, namely chlorogenic, caffeic, p-coumaric, rosmarinic, gallic and tannic acids in the concentration range 0.5-500 µM, against Escherichia coli and Lactobacillus rhamnosus. The antimicrobial activity was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide colorimetric assay. Additionally, the cytotoxic effects of these phenolic acids on two cancer cell lines, the colorectal adenocarcinoma Caco-2 cell line and Dukes' type C colorectal adenocarcinoma DLD-1 cell line was examined. To further understand the molecular properties of these phenolic acids, quantum chemical calculations were performed using the Gaussian 09W program. Parameters such as ionization potential, electron affinity, electronegativity, chemical hardness, chemical softness, dipole moment, and electrophilicity index were obtained. The lipophilicity properties represented by logP parameter was also discussed. This study provides a comprehensive evaluation of the antimicrobial and cytotoxic activity of six phenolic acids, compounds deliberately selected due to their chemical structure. They are derivatives of benzoic or cinnamic acids with the increasing number of hydroxyl groups in the aromatic ring. The integration of experimental and computational methodologies provides a knowledge of the molecular characteristics of bioactive compounds and partial explanation of the relationship between the molecular structure and biological properties. This knowledge aids in guiding the development of bioactive components for use in dietary supplements, functional foods and pharmaceutical drugs.


Assuntos
Hidroxibenzoatos , Humanos , Hidroxibenzoatos/química , Hidroxibenzoatos/farmacologia , Células CACO-2 , Linhagem Celular Tumoral , Escherichia coli/efeitos dos fármacos , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Testes de Sensibilidade Microbiana , Ácido Gálico/química , Ácido Gálico/farmacologia , Cinamatos/química , Cinamatos/farmacologia , Ácidos Cafeicos/química , Ácidos Cafeicos/farmacologia , Ácidos Cumáricos/química , Ácidos Cumáricos/farmacologia
13.
Molecules ; 29(11)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38893343

RESUMO

Polyphenols are plant secondary metabolites that function mostly as a general stress-induced protective mechanism. Polyphenols have also gained interest due to their beneficial properties for human health. Strawberry leaves represent an agro-industrial waste material with relevant bioactive polyphenol content, which could be incorporated into circular economy strategies. However, due to the low quantities of polyphenols in plants, their production needs to be improved for cost-effective applications. The objective of this research was to compare polyphenol production in strawberry (Fragaria × ananassa cv. Festival) leaves in plants grown in greenhouse conditions and plants grown in vitro, using three possible elicitor treatments (UV irradiation, cold exposure, and cysteine). General vegetative effects were morphologically evaluated, and specific polyphenolic compounds were quantified by UHPLC-DAD-MS/MS. Gallic acid was the most abundant polyphenol found in the leaves, both in vivo and in vitro. The results showed higher amounts and faster accumulation of polyphenols in the in vitro regenerated plants, highlighting the relevance of in vitro tissue culture strategies for producing compounds such as polyphenols in this species and cultivar.


Assuntos
Fragaria , Folhas de Planta , Polifenóis , Fragaria/química , Fragaria/metabolismo , Polifenóis/química , Folhas de Planta/química , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão , Ácido Gálico/química
14.
Talanta ; 277: 126345, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38878507

RESUMO

In this work, we present a dual-mode assay system consisting of a nanozyme and a luminogen with the aggregation-induced emission (AIE) feature. In the assay system, the chosen nanozyme named CuCo-0 catalyzes the substrate to produce colorimetric signals, while the aggregates of H4ETTC (4,4',4″,4‴-(ethene-1,1,2,2-tetrayl) tetrakis ([1,1'-biphenyl]-4-carboxylic acid), a typical AIE luminogen, generate fluorescent signals. The peroxidase-like activity of the CuCo-0 nanozyme can be remarkably suppressed with sequential additions of antioxidants, leading to a dual-signal response characterized by enhanced fluorescence emission and reduced UV-vis absorbance. On this basis, a dual-mode assay capable of producing both colorimetric and fluorescent signals for the assessment of antioxidant capacity using gallic acid as a representative antioxidant was exploited. Good linearity can be obtained in the 0-60 µM range for both colorimetric analysis and fluorescent analysis, with detection limits of 1.3 µM and 0.35 µM, respectively. Furthermore, this dual-mode assay was successfully applied to real gallnut samples, yielding satisfactory results.


Assuntos
Antioxidantes , Colorimetria , Cobre , Colorimetria/métodos , Antioxidantes/análise , Antioxidantes/química , Cobre/química , Cobre/análise , Espectrometria de Fluorescência/métodos , Ácido Gálico/análise , Ácido Gálico/química , Corantes Fluorescentes/química , Limite de Detecção
15.
Food Res Int ; 188: 114510, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823887

RESUMO

The aim of this study was to explore the copigmentation effect of gallic acid on red wine color and to dissect its mechanism at the molecular level. Three-dimensional studies, e.g., in model wine, in real wine and in silico, and multiple indicators, e.g., color, spectrum, thermodynamics and phenolic dynamics, were employed. The results showed that gallic acid significantly enhanced the color quality and stability of red wine. Physico-chemical interactions and chemical transformations should be the most likely mechanism, and physico-chemical interactions are also a prerequisite for chemical transformations. QM calculations of the physico-chemical interactions proved that the binding between gallic acid and malvidin-3-O-glucoside is a spontaneous exothermic reaction driven by hydrogen bonding and dispersion forces. The sugar moiety of malvidin-3-O-glucoside and the phenolic hydroxyl groups of gallic acid affect the formation of hydrogen bonds, while the dispersion interaction was related to the stacking of the molecular skeleton.


Assuntos
Antocianinas , Cor , Ácido Gálico , Glucosídeos , Ligação de Hidrogênio , Termodinâmica , Vinho , Ácido Gálico/química , Vinho/análise , Glucosídeos/química , Antocianinas/química , Teoria Quântica , Fenóis/química
16.
J Food Sci ; 89(6): 3577-3590, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38720591

RESUMO

This study investigated preheated (25-100°C) black soybean protein isolate (BSPI) conjugated with syringic acid (SA) (25 and 50 µmol/g protein) under alkaline conditions, focusing on the structure, functional properties, and storage stability. The results revealed that the SA binding equivalent and binding rate on BSPI increased continuously as the preheat temperature increased. Additionally, preheating positively impacted the surface hydrophobicity (H0) of BSPI, with further enhancement observed upon SA binding. Preheating and SA binding altered the secondary and tertiary structure of BSPI, resulting in protein unfolding and increased molecular flexibility. The improvement in BSPI functional properties was closely associated with both preheating temperature and SA binding. Specifically, preheating decreased the solubility of BSPI but enhanced the emulsifying activity index (EAI) and foaming capacity (FC) of BSPI. Conversely, SA binding increased the solubility of BSPI with an accompanying increase in EAI, FC, foaming stability, and antioxidant activity. Notably, the BSPI100-SA50 exhibited the most significant improvement in functional properties, particularly in solubility, emulsifying, and foaming attributes. Moreover, the BSPI-SA conjugates demonstrated good stability of SA during storage, which positively correlated with the preheating temperature. This study proposes a novel BSPI-SA conjugate with enhanced essential functional properties, underscoring the potential of preheated BSPI-SA conjugates to improve SA storage stability. PRACTICAL APPLICATION: Preheated BSPI-SA conjugates can be used as functional ingredients in food or health products. In addition, preheated BSPI shows potential as a candidate for encapsulating and delivering hydrophobic bioactive compounds.


Assuntos
Ácido Gálico , Temperatura Alta , Interações Hidrofóbicas e Hidrofílicas , Solubilidade , Proteínas de Soja , Proteínas de Soja/química , Ácido Gálico/análogos & derivados , Ácido Gálico/química , Glycine max/química , Antioxidantes/química , Estabilidade Proteica
17.
Anal Methods ; 16(23): 3663-3674, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38804266

RESUMO

The present study describes an efficient method for the determination of polyphenol content in beverages based on a composite material of graphene oxide decorated with Prussian blue nanocubes (rGO/PBNCs). In this method, rGO/PBNCs act as a nanoenzyme with peroxidase-like catalytic activity and produce a colorimetric product in the presence of hydrogen peroxide and tetramethylbenzidine (TMB). To verify the effectiveness of the method, we used two model standards for antioxidants: gallic acid (GA) and tannic acid (TA). The method validation included a comparison of the performance of a natural enzyme and an artificial one (rGO/PBNCs) and two polyphenols in the analysis of commercial beverage samples. After optimization, a pH of 4, ambient temperature (22 °C), a reaction time of 2 minutes and an rGO/PBNCs concentration of 0.01 µg mL-1 were found to be the most favorable conditions. The detection limits obtained were 5.6 µmol L-1 for GA and 1.5 µmol L-1 for TA. Overall, rGO/PBNCs offer advantages over natural enzymes in terms of stability, versatility, scalability and durability, making them attractive candidates for a wide range of catalytic and sensory applications.


Assuntos
Bebidas , Ferrocianetos , Grafite , Polifenóis , Polifenóis/análise , Polifenóis/química , Ferrocianetos/química , Grafite/química , Bebidas/análise , Colorimetria/métodos , Limite de Detecção , Peroxidase/química , Ácido Gálico/química , Ácido Gálico/análise , Taninos/química , Taninos/análise , Peróxido de Hidrogênio/química , Benzidinas/química , Antioxidantes/química , Antioxidantes/análise
18.
ACS Appl Bio Mater ; 7(5): 3375-3387, 2024 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-38693867

RESUMO

Encapsulation of natural polymer pectin (Pec) into a zeolitic imidazolate framework-12 (ZIF-12) matrix via a simple chemical method toward anticancer agent gallic acid (GA) detection is reported in this work. GA, a natural phenol found in many food sources, has gained attention by its biological effects on the human body, such as an antioxidant and anti-inflammatory. Therefore, it is crucial to accurately and rapidly determine the GA level in humans. The encapsulation of Pec inside the ZIF-12 has been successfully confirmed from the physiochemical studies such as XRD, Raman, FTIR, and XPS spectroscopy along with morphological FESEM, BET, and HRTEM characterization. Under optimized conditions, the Pec@ZIF-12 composite exhibits wide linear range of 20 nM-250 µM with a detection limit of 2.2 nM; also, it showed excellent selectivity, stability, and reproducibility. Furthermore, the real sample analysis of food samples including tea, coffee, grape, and pomegranate samples shows exceptional recovery percentage in an unspiked manner. So far, there is little literature for encapsulating proteins, enzymes, metals, etc., that have been reported; here, we successfully encapsulated a natural polymer Pec inside the ZIF-12 cage. This encapsulation significantly enhanced the composite electrochemical performance, which could be seen from the overall results. All of these strongly suggest that the proposed Pec@ZIF-12 composite could be used for miniaturized device fabrication for the evaluation of GA in both home and industrial applications.


Assuntos
Antineoplásicos , Técnicas Eletroquímicas , Imidazóis , Zeolitas , Zeolitas/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Imidazóis/química , Teste de Materiais , Ácido Gálico/química , Tamanho da Partícula , Materiais Biocompatíveis/química , Polímeros/química , Pectinas/química , Estruturas Metalorgânicas/química , Humanos
19.
Food Chem ; 453: 139701, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-38781907

RESUMO

The current study offers the nanomolar quantification of gallic acid (GAL) based on gold nanoparticles (AuNps) and kaolinite minerals (KNT) modified on a screen-printed electrode (SPE). The electrochemical behavior of GAL was performed using differential pulse voltammetry (DPV) in Britton Robinson (BR) buffer solution at pH 2.0 as a supporting electrolyte. Under the optimized DPV mode parameters, the oxidation peak current of GAL (at 0.72 V vs Ag/AgCl) increased linearly in the range between 0.002 µmolL-1 and 40.0 µmolL-1 with a detection limit of 0.50 nmolL-1. The effect of common interfering agents was also investigated. Finally, the applicability of the proposed method was verified by quantification analysis of GAL in black tea and pomegranate juice samples.


Assuntos
Técnicas Eletroquímicas , Eletrodos , Ácido Gálico , Ouro , Caulim , Nanopartículas Metálicas , Nanopartículas Metálicas/química , Ouro/química , Ácido Gálico/análise , Ácido Gálico/química , Caulim/química , Técnicas Eletroquímicas/instrumentação , Limite de Detecção , Punica granatum/química , Chá/química , Minerais/análise , Minerais/química , Sucos de Frutas e Vegetais/análise , Camellia sinensis/química , Contaminação de Alimentos/análise
20.
Int J Biol Macromol ; 270(Pt 1): 131831, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38702246

RESUMO

Lately, emulsions with low-fat and natural stabilizers are predominant. This study extracted the nano cellulose crystals (NCs) from Camellia Oleifera shells, and their gallic acid (GA) conjugates were synthesized by free-radical grafting. Pickering emulsions were prepared using NCs 1 %, 1.5 %, 2.5 %, and gallic acid conjugates NC-GA1, NC-GA2, and NC-GA3 as stabilizers. The obtained nano cellulose crystals exhibited 18-25 nm, -40.01 ±â€¯2.45 size, and zeta potential, respectively. The contact angle of 83.4° was exhibited by NC-GA3 conjugates. The rheological, interfacial, and microstructural properties and stability of the Pickering emulsion were explored. NC-GA3 displayed the highest absorption content of 79.12 %. Interfacial tension was drastically reduced with increasing GA concentration in NC-GA conjugates. Rheological properties suggested that the low-fat NC-GA emulsions showed a viscoelastic behavior, increased viscosity, gel-like structure, and increased antioxidant properties. Moreover, NC-GA3 displayed reduced droplet size and improved emulsion temperature and storage stability (28 days) against phase separation. POV and TBARS values were reduced with the NC-GA3 (P < 0.05). This work confirmed that grafting phenolic compounds on NCs could enhance bioactive properties, which can be used in developing low-fat functional foods. NC-GA conjugates can potentially fulfill the increasing demand for sustainable, healthy, and low-fat foods.


Assuntos
Antioxidantes , Camellia , Celulose , Emulsões , Ácido Gálico , Reologia , Camellia/química , Ácido Gálico/química , Celulose/química , Antioxidantes/química , Viscosidade , Nanopartículas/química , Cristalização
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