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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 290: 122268, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36580754

RESUMO

Hypochlorous acid (HClO) plays an important role in many physiological and pathological activities. In this work, a novel BODIPY-based Near-infrared (NIR) ratiometric fluorescent probe BODIPY-Hyp was designed for the rapid detection of HClO. The probe BODIPY-Hyp was highly selective and sensitive for HClO with a low detection limit of 16.74 nM and short response time of less than 60 s. The probe BODIPY-Hyp in response to HClO exhibited a significant blue-shifted fluorescence emission from 700 nm to 530 nm, and its fluorescence intensity ratio (I530 nm/I700 nm) increased about 1200 times before and after adding HClO. Moreover, the reaction mechanism of BODIPY-Hyp with HClO was verified by HRMS analysis, 1H NMR titration and DFT calculations. Furthermore, BODIPY-Hyp was successfully processed into a portable test strip-based device for the detection of HClO. In addition, the probe BODIPY-Hyp could be used in real time to monitor the levels of HClO in living zebrafish larvae. In conclusion, BODIPY-Hyp has great application potential in the life and environmental sciences.


Assuntos
Corantes Fluorescentes , Peixe-Zebra , Animais , Corantes Fluorescentes/química , Compostos de Boro/química , Ácido Hipocloroso/análise , Água
2.
Front Nutr ; 9: 1031550, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36276842

RESUMO

The advanced glycation end products (AGEs) are formed in baked products through the Maillard reaction (MR), which are thought to be a contributing factor to chronic diseases such as heart diseases and diabetes. Lotus seedpod oligomeric procyanidins (LSOPC) are natural antioxidants that have been added to tough biscuit to create functional foods that may lower the risk of chronic diseases. The effect of LSOPC on AGEs formation and the sensory quality of tough biscuit were examined in this study. With the addition of LSOPC, the AGEs scavenging rate and antioxidant capacity of LSOPC-added tough biscuits were dramatically improved. The chromatic aberration (ΔE) value of tough biscuits containing LSOPC increased significantly. Higher addition of LSOPC, on the other hand, could effectively substantially reduced the moisture content, water activity, and pH of LSOPC toughen biscuits. These findings imply that using LSOPC as additive not only lowers the generation of AGEs, but also improves sensory quality of tough biscuit.

3.
Bioresour Technol ; 350: 126885, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35217157

RESUMO

A novel pretreatment system containing deep eutectic solvents and ethanol (DES-E) for synergistic carbohydrate conversion and delignification was reported in this study. The DES-E pretreatment resulted in an enhanced glucose yield compared to individual DES and ethanol pretreatment for the three tested biomass, including Broussonetia papyrifera, corn stover and pine. To further explore the delignification mechanism, the solubilized lignin and residual lignin from Broussonetia papyrifera was recovered and extracted, then thoroughly characterized. The highest total OH content was found in the DES-E solubilized lignin, which could be used as antioxidant. The presence of ethanol in pretreatment liquor could protect the ß-O-4 substructure from breakage and reduce lignin condensation, which favors the subsequent enzymatic hydrolysis. Comparable glucose yield and delignification performance was achieved by recycled DES. DES-E pretreatment offers a promising method for lignin isolation and cellulose digestibility improvement simultaneously.


Assuntos
Solventes Eutéticos Profundos , Lignina , Biomassa , Etanol , Hidrólise , Lignina/química , Solventes/química
4.
Food Sci Nutr ; 9(12): 6575-6586, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34925787

RESUMO

The discovery of new edible flowers that are nontoxic, innocuous flowers having human health benefits, surveys of their phytochemicals and utilization are of great scientific and commercial interest. Dendrobium officinale and Dendrobium devonianum are precious Traditional Chinese Medicine. During the massive commercial cultivation, a lot of flowers were produced and certified as edible flowers, and the phytochemical profiles and bioactivities warrant evaluate. The present study aimed to investigate the phytochemicals and antioxidative activities in flowers of D. officinale (DOF) and D. devonianum (DDF). In total, 474 metabolites were identified using a widely targeted metabonomics method, 16 amino acids and 6 flavonoids were measured using high-performance liquid chromatography (HPLC), and 8 fatty acids were detected using gas chromatography-mass spectrometry (GC-MS). Both flowers contained various amino acids, including 7 essential amino acids, diverse flavonoids, especially quercetin, kaempferol and their derivatives, and high levels of methyl linoleate and methyl linolenate. The relative levels of quercetin, kaempferol and their glycosides were higher in DDF than in DOF, whereas the relative levels of several flavonoids C-glycosides were high in DOF. Ethanol extracts of both DOF and DDF showed antioxidative capacities including the scavenging of 1,1-diphenyl-2-picrylhydrazyl and hydroxyl radicals. Both edible flowers contained flavonoids, amino acids, and fatty acids and have antioxidative activities, which should be explored for use in functional foods and pharmaceuticals.

5.
Food Chem ; 334: 127560, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32711271

RESUMO

Post-fermented Pu-erh tea (PFPT) is a microbially-fermented tea with distinct sensory qualities and multiple health benefits. Aspergillus are the dominant fungi in the fermentation and the main contributors to the characteristics of PFPT, so their underlying functions warrant detailed study. Here, tea leaves were fermented by Aspergillus niger, Aspergillus tamarii and Aspergillus fumigatus, and resulting samples (designated as Asn, Ast and Asf, respectively) were analyzed by proteomic and metabolomic methods. Changes to the composition of flavonoids, glycerophospholipids, organo-oxygen compounds and fatty acids resulting from Aspergillus fermentation were observed. Carbohydrate-active enzymes, e.g., endoglucanases and cellulases, for degradation of cellulose, starch, lignin, pectin, xylan and xyloglucan were identified. Glycoside hydrolase, glycosyltransferases, tannase, laccases, vanillyl-alcohol oxidases and benzoquinone reductase were identified and hypothesized to catalyze hydrolysis, oxidation, polymerization and degradation of phenolic compounds. Together, functions of Aspergillius were demonstrated as production of enzymes to change concentrations and compositions of metabolites in tea leaves.


Assuntos
Aspergillus/fisiologia , Camellia sinensis/microbiologia , Enzimas/metabolismo , Folhas de Planta/microbiologia , Chá , Aspergillus/enzimologia , Aspergillus fumigatus/enzimologia , Aspergillus fumigatus/fisiologia , Aspergillus niger/enzimologia , Aspergillus niger/fisiologia , Metabolismo dos Carboidratos , Fermentação , Flavonoides/análise , Flavonoides/metabolismo , Microbiologia de Alimentos/métodos , Proteínas Fúngicas/metabolismo , Glicerofosfolipídeos/metabolismo , Metabolômica/métodos , Fenóis/análise , Fenóis/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Proteínas de Plantas/análise , Proteínas de Plantas/metabolismo , Proteômica/métodos , Chá/química , Chá/metabolismo , Chá/microbiologia
6.
J Agric Food Chem ; 68(17): 4946-4954, 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32275834

RESUMO

Tannase (E.C. 3.1.1.20) is hypothesized to be involved in the metabolism of gallates and gallic acid (GA) in pu-erh tea fermentation. In this work, we measured tannase in Aspergillus niger fermented tea leaves and confirmed the production of fungal tannase during pu-erh tea fermentation. A decrease in catechin and theaflavin gallates and a significant increase in GA content and the relative peak areas of ethyl gallate, procyanidin A2, procyanidin B2, procyanidin B3, catechin-catechin-catechin, epiafzelechin, and epicatechin-epiafzelechin [variable importance in the projection (VIP) > 1.0, p < 0.05, and fold change (FC) > 1.5] were observed using high performance liquid chromatography (HPLC) and metabolomics analysis of tea leaves fermented or hydrolyzed by tannase. In vitro assays showed that hydrolysis by tannase or polymerization of catechins increased the antioxidant activity of tea leaves. In summary, we identified a metabolic pathway for gallates and their derivatives in tea leaves hydrolyzed by tannase as well as associated changes in gallate and GA concentrations caused by fungal tannase during pu-erh tea fermentation.


Assuntos
Aspergillus niger/metabolismo , Camellia sinensis/microbiologia , Hidrolases de Éster Carboxílico/metabolismo , Proteínas Fúngicas/metabolismo , Ácido Gálico/metabolismo , Aspergillus niger/química , Aspergillus niger/enzimologia , Camellia sinensis/química , Camellia sinensis/metabolismo , Hidrolases de Éster Carboxílico/química , Cromatografia Líquida de Alta Pressão/métodos , Fermentação , Proteínas Fúngicas/química , Ácido Gálico/química , Metabolômica/métodos , Folhas de Planta/química , Folhas de Planta/metabolismo , Folhas de Planta/microbiologia
7.
Electrophoresis ; 40(21): 2837-2844, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31353482

RESUMO

Tea is the second most widely consumed beverage and contains various bioactive compounds. A simple method to analyze these compounds is of great scientific and commercial interest. In this work, a 30 min HPLC method was developed using a simple gradient elution system, and the mobile phases and elution gradients were optimized. This method separated 17 polyphenols and three alkaloid compounds in tea extracts, including catechins, alkaloids, phenolic acids, flavonols, and flavone, which are responsible for the bioactivity and flavor of tea. Excellent linearity was observed for all standard calibration curves, and correlation coefficients were above 0.9994. Heatmap analysis demonstrated significant separation between green, black, and pu-erh tea samples. The method described here is accurate and sensitive enough for the determination of active components in tea and could potentially be applied to other food products for the comprehensive investigation of their quality.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/análise , Extratos Vegetais/química , Chá/química , Alcaloides/análise , Hidroxibenzoatos/análise , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes
8.
Artigo em Inglês | MEDLINE | ID: mdl-26160605

RESUMO

Two new organic-inorganic molecular solids of tetra(isothiocyanate)cobalt(II) dianion and disubstituted benzyl triphenylphosphinium, [2Cl4FBzTPP]2[Co(NCS)4] (1) and [2Cl4ClBzTPP]2[Co(NCS)4] (2) ([2Cl4FBzTPP](+)=1-(2'-chloro-4'-fluorobenzyltriphenylphosphonium) and [2Cl4ClBzTPP](+)=1-(2',4'-dichlorobenzyltriphenylphosphonium), were synthesized and characterized by elemental analysis, FT-IR, UV-Vis spectra, ESI-MS and single crystal X-ray diffraction method. Compounds 1 and 2 crystallize in the monoclinic Pc and triclinic P-1, respectively. The Co(II) ion of the [Co(NCS)4](2-) anion shows a distorted tetrahedral coordination geometry. The [2Cl4FBzTPP](+) cations containing P(2) atoms in 1 form a column by the Cl⋯π interactions, while the [2Cl4ClBzTPP](+) cations in 2 form two columns by the C-H⋯π and π⋯π interactions. The anion and the cation are linked by C-H⋯S hydrogen bonds and Cl⋯S interactions. Magnetic susceptibility measurement in the temperature range 2-300K shows that both 1 and 2 exhibit a weak antiferromagnetic exchange interaction as the temperature falls, and ultraviolet fluorescence emission in the solid state at room temperature.

9.
Spectrochim Acta A Mol Biomol Spectrosc ; 142: 239-45, 2015 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-25703370

RESUMO

The reaction of CoCl2 with the naphthalene methylated triphenylphosphinium bromide [n-NAPMeTPP]Br (n=1, 2) and KSCN, in a methanolic medium at ambient temperature, leads to the self-assembly formation of hybrid 2:1 organic-inorganic molecular solids, [1-NAPMeTPP]2[Co(NCS)4](1) and [2-NAPMeTPP]2[Co(NCS)4](2) ([NAPMeTPP](+)=(naphthylmethylene)(triphenyl)phosphinium), which have been characterized by elemental analyses, IR spectroscopy, UV-Vis spectra, ESI-MS, molar conductivity and single-crystal X-ray diffraction structural analyses. Compound 1 crystallizes in the orthorhombic space group Pna21, while 2 does in the monoclinic space group C2/c. The cations form a dimer through the weak intermolecular C-H⋯π interactions in 1 and π⋯π interaction in 2, while the anion and cation are linked by the C-H⋯S hydrogen bond in 1. Two molecular solids show dual functionalities: (1) the broad fluorescence emission around 400nm in the solid state at room temperature; (2) the weak antiferromagnetic coupling behavior.


Assuntos
Cobalto/química , Isotiocianatos/química , Substâncias Luminescentes/química , Imãs/química , Naftalenos/química , Fosfinas/química , Cátions/química , Cristalografia por Raios X , Dimerização , Fluorescência , Isotiocianatos/síntese química , Luminescência , Substâncias Luminescentes/síntese química , Modelos Moleculares , Naftalenos/síntese química , Fosfinas/síntese química
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