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1.
Food Chem ; 317: 126415, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32087518

RESUMO

This paper focused on improving antityrosinase ability of quercetin, cinnamic acid, and ferulic acid (named Q-CA-FA) from Asparagus by combining heating with ultrasound treatments. Fluorescence spectroscopy and UPLC-MS were used to evaluate inhibitory mechanisms. Results showed that the impacts of combining heating (150 °C for 30 min) with ultrasound (600 W for 30 min) treatments were similar to heating treatment (150 °C for 120 min) alone, and the inhibition rate could reach 98.2% in the addition of 5 mM Q-CA-FA. Fluorescence quenching indicated that treated Q-CA-FA-tyrosinase complex was more stable, but combining treatments did not change the major force between tyrosinase and polyphenols. Thermodynamic analysis illustrated that the randomness of compounds was also increased. Interestingly, 2-hydroxy-3-(3-hydroxy-4-methoxy-phenyl)-propionic acid 4-(2,3-dihydroxy-propyl)-phenyl ester was newly detected, which might be the major reason for enhancing antityrosinase ability. Taken together, these results provide a creative insight on increasing antityrosinase activity by combining heating with ultrasound treatments.


Assuntos
Monofenol Mono-Oxigenase/metabolismo , Polifenóis/metabolismo , Sonicação , Asparagus (Planta)/química , Asparagus (Planta)/metabolismo , Cromatografia Líquida de Alta Pressão , Cinamatos/análise , Cinamatos/metabolismo , Ácidos Cumáricos/análise , Ácidos Cumáricos/metabolismo , Temperatura Alta , Monofenol Mono-Oxigenase/antagonistas & inibidores , Polifenóis/análise , Quercetina/análise , Quercetina/metabolismo , Espectrometria de Fluorescência , Espectrometria de Massas em Tandem , Termodinâmica
2.
J Photochem Photobiol B ; 204: 111819, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32062388

RESUMO

Solanum aculeatissimum Jacq. is a common plant in much of Brazil. Despite containing metabolites with a wide range of pharmacological applications, there are few tissue culture reports for this plant. The possibility of large-scale in vitro production of this material has significant biotechnological potential. Therefore, the objective of this study was to investigate the effect of light conditions on the growth of cells in suspension, observing the production and yield of biomass and bioactive compounds and the enzymatic behavior. Calli obtained from leaf segments were cultured in solid medium supplemented with 1 mg L-1 of 2,4-D, 2.5 mg L-1 kinetin, pH 5.7, in the dark. After 110 days of subculture, the calli were transferred to liquid medium. Cells were kept in the dark under agitation at 110 rpm and 25 °C and subcultured every 30 days. After 90 days of culture, 20 mL aliquots of cell suspension were added to flasks containing approximately 20 mL of medium (1:1) and cultured at different wavelengths (white, green, blue, red, and blue/red) under a photoperiod of 16 h with irradiance of 50 µmol m-2 s-1) and in the absence of light. The experiment was performed in a 6 × 6 factorial design (light condition × culture time). The cell cultures showed viability throughout the entire cycle, and chlorogenic and ferulic acids, orientin, quercitrin and, in higher amounts, quercetin, were detected in the first 7 days of culture. There was an increase in superoxide dismutase and catalase and a decrease in ascorbate peroxidase after exposure to different light conditions; for phenylalanine ammonia lyase, no differences were observed. The different light conditions were not sufficient to trigger responses in the concentrations of bioactive compounds, despite the detection of increased levels of the enzymes involved in cellular homeostasis.


Assuntos
Luz , Solanum/metabolismo , Catalase/metabolismo , Técnicas de Cultura de Células , Ácido Clorogênico/metabolismo , Condutividade Elétrica , Flavonoides/metabolismo , Glucosídeos/metabolismo , Concentração de Íons de Hidrogênio , Células Vegetais/metabolismo , Células Vegetais/efeitos da radiação , Folhas de Planta/citologia , Folhas de Planta/metabolismo , Quercetina/análogos & derivados , Quercetina/metabolismo , Solanum/citologia , Superóxido Dismutase/metabolismo
3.
Food Chem ; 314: 126166, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31972406

RESUMO

The occurrence of the quercetin oxidation metabolite 2-(3,4-dihydroxybenzoyl)-2,4,6-trihydroxy-3(2H)-benzofuranone (BZF), whose antioxidant potency is notably higher than the antioxidant potency of quercetin, was investigated in twenty quercetin-rich plant foods. BZF was identified (HPLC-DAD-ESI-MS/MS) only in the dry outer scales of onions and shallots. Aqueous extracts of onions (OAE) and shallots (SAE) were evaluated for their antioxidant and cytoprotective properties. OAE, whose potency did not differ from SAE, protected ROS-exposed Caco2 cells against oxidative (78%) and cellular (90%) damage at a 3 µg/L concentration (corresponding to 0.03 nM of BZF). After chromatographic resolution of OAE, the BZF peak accounted fully and exclusively for its antioxidant effect. The antioxidant effects of OAE and of a pure BZF were described by two perfectly overlapping curves whose concentration-dependence was within the 3 × 10-4 to 102 nM BZF range. Such unprecedented low concentrations place BZF-containing plants on the frontier of the search for novel sources of antioxidants.


Assuntos
Antioxidantes/farmacologia , Benzofuranos/análise , Benzofuranos/farmacologia , Cebolas/química , Quercetina/metabolismo , Antioxidantes/química , Benzofuranos/metabolismo , Células CACO-2 , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Frutas/química , Humanos , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Substâncias Protetoras/química , Substâncias Protetoras/farmacologia , Espectrometria de Massas em Tandem , Verduras/química
4.
Prep Biochem Biotechnol ; 50(1): 1-9, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31441715

RESUMO

Isoquercitrin is a flavonoid with important applications in the pharmaceutical and nutraceutical industries. However, a low yield and high production cost hinders the industrial preparation of isoquercitrin. In the present study, isoquercitrin was prepared by biotransformation of rutin using α-L-rhamnosidase from Aspergillus niger JMU-TS528 combined with high-speed countercurrent chromatography (HSCCC) purification. As a result, the optimum transformation pH, temperature, and time were pH 4.0, 60 °C, and 60 min, respectively. The Km and Vmax were 0.36 mM and 0.460 mmol/min, respectively. For isoquercitrin production, the optimal rutin concentration and transformation time were approximately 1000 mg/L and 60 min. The rutin transformation rate reached 96.44%. The isoquercitrin was purified to a purity of 97.83% using one-step purification with HSCCC. The isoquercitrin was identified using UPLC-Q-TOF-MS. The comprehensive results indicated that the biotransformation procedure using the α-L-rhamnosidase from A. niger JMU-TS528 combined with HSCCC was a simple and effective process to prepare isoquercitrin, which might facilitate the production of isoquercitrin for industrial use.


Assuntos
Aspergillus niger/metabolismo , Glicosídeo Hidrolases/metabolismo , Quercetina/análogos & derivados , Rutina/metabolismo , Biotransformação , Distribuição Contracorrente , Microbiologia Industrial , Quercetina/isolamento & purificação , Quercetina/metabolismo
5.
Food Chem ; 309: 125667, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31679851

RESUMO

This research firstly investigated the inhibitory effect of isoquercitrin (ISQ) on Ovalbumin (OVA) glycation. The mechanism was elucidated through the interaction between OVA and ISQ, and changes in glycation sites and degree of each site as deduced by spectroscopy, spectrometry and molecular docking. ISQ significantly inhibited OVA glycation by attenuating the conformational change induced by glycation. It quenched the fluorescence of Trp via static mechanism, and exposed Trp residues to a more hydrophobic surroundings. Formation of OVA-ISQ complex was a endothermic processing driven by hydrophobic interactions, van der Waals forces and hydrogen bonds. LC-Orbitrap-MS/MS revealed that ISQ altered the location of glycation and alleviated the glycation degree of most sites. Molecular docking results indicated that ISQ inserted into the hydrophobic pocket of OVA with six hydrogen bonds and one π-π stacking formed between ISQ and the amino acid residues of OVA, leading to the altered glycation activity of some sites.


Assuntos
Simulação de Acoplamento Molecular , Ovalbumina/metabolismo , Quercetina/análogos & derivados , Espectrometria de Fluorescência , Sítios de Ligação , Cromatografia Líquida de Alta Pressão , Glicosilação , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Ovalbumina/química , Peptídeos/análise , Ligação Proteica , Quercetina/química , Quercetina/metabolismo , Espectrometria de Massas em Tandem , Termodinâmica
6.
BMC Complement Altern Med ; 19(1): 346, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31791311

RESUMO

BACKGROUND: Influenza A virus (IAV) is still a major health threat. The clinical manifestations of this infection are related to immune dysregulation, which causes morbidity and mortality. The usage of traditional medication with immunomodulatory properties against influenza infection has been increased recently. Our previous study showed antiviral activity of quercetin-3-O-α-L-rhamnopyranoside (Q3R) isolated from Rapanea melanophloeos (RM) (L.) Mez (family Myrsinaceae) against H1N1 (A/PR/8/34) infection. This study aimed to confirm the wider range of immunomodulatory effect of Q3R on selective pro- and anti-inflammatory cytokines against IAV in vitro, to evaluate the effect of Q3R on apoptosis pathway in combination with H1N1, also to assess the physical interaction of Q3R with virus glycoproteins and RhoA protein using computational docking. METHODS: MDCK cells were exposed to Q3R and 100CCID50/100 µl of H1N1 in combined treatments (co-, pre- and post-penetration treatments). The treatments were tested for the cytokines evaluation at RNA and protein levels by qPCR and ELISA, respectively. In another set of treatment, apoptosis was examined by detecting RhoA GTPase protein and caspase-3 activity. Molecular docking was used as a tool for evaluation of the potential anti-influenza activity of Q3R. RESULTS: The expressions of cytokines in both genome and protein levels were significantly affected by Q3R treatment. It was shown that Q3R was much more effective against influenza when it was applied in co-penetration treatment. Q3R in combination with H1N1 increased caspase-3 activity while decreasing RhoA activation. The molecular docking results showed strong binding ability of Q3R with M2 transmembrane, Neuraminidase of 2009 pandemic H1N1, N1 and H1 of PR/8/1934 and Human RhoA proteins, with docking energy of - 10.81, - 10.47, - 9.52, - 9.24 and - 8.78 Kcal/mol, respectively. CONCLUSIONS: Quercetin-3-O-α-L-rhamnopyranoside from RM was significantly effective against influenza infection by immunomodulatory properties, affecting the apoptosis pathway and binding ability to viral receptors M2 transmembrane and Neuraminidase of 2009 pandemic H1N1 and human RhoA cellular protein. Further research will focus on detecting the detailed specific mechanism of Q3R in virus-host interactions.


Assuntos
Antivirais , Glicosídeos , Vírus da Influenza A Subtipo H1N1 , Myrsine/química , Compostos Fitoquímicos , Quercetina/análogos & derivados , Animais , Antivirais/química , Antivirais/metabolismo , Antivirais/farmacologia , Apoptose/efeitos dos fármacos , Citocinas/metabolismo , Cães , Glicosídeos/química , Glicosídeos/metabolismo , Glicosídeos/farmacologia , Células Madin Darby de Rim Canino , Simulação de Acoplamento Molecular , Neuraminidase/química , Neuraminidase/metabolismo , Compostos Fitoquímicos/química , Compostos Fitoquímicos/metabolismo , Compostos Fitoquímicos/farmacologia , Quercetina/química , Quercetina/metabolismo , Quercetina/farmacologia , Proteínas da Matriz Viral/química , Proteínas da Matriz Viral/metabolismo
7.
Proc Biol Sci ; 286(1917): 20192041, 2019 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-31847772

RESUMO

As a managed agricultural pollinator, the western honeybee Apis mellifera frequently encounters agrochemicals as contaminants of nectar and pollen. One such contaminant, the fungicide boscalid, is applied at bloom in orchards for fungal floral pathogen control. As an inhibitor of complex II in the mitochondrial electron transport chain of fungi, boscalid can potentially interfere with high energy-demanding activities of bees, including flight. We designed an indoor flight treadmill to evaluate impacts of ingesting boscalid and/or quercetin, a ubiquitous phytochemical in bee food that also affects mitochondrial respiration. Boscalid reduced the wingbeat frequencies of foragers during flight but did not alter the duration of flight. At the colony level, boscalid ingestion may thereby affect overall health by reducing forager efficiency. The consumption of quercetin, by contrast, led to higher adenosine triphosphate levels in flight muscles and a higher wingbeat frequency. Consuming the two compounds together increased wingbeat frequency, demonstrating a hitherto unrecognized mechanism by which dietary phytochemicals may act to ameliorate toxic effects of pesticides to promote honeybee health. In carrying out this work, we also introduce two methodological improvements for use in testing for pesticide effects on flight capacity-a 'force-feeding' to standardize flight fuel supply and a novel indoor flight treadmill.


Assuntos
Abelhas/fisiologia , Compostos de Bifenilo/toxicidade , Voo Animal/efeitos dos fármacos , Fungicidas Industriais/toxicidade , Niacinamida/análogos & derivados , Animais , Antioxidantes/metabolismo , Niacinamida/toxicidade , Substâncias Protetoras , Quercetina/metabolismo
8.
Molecules ; 24(20)2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31615126

RESUMO

Chrysanthemum morifolium. cv "Hangju" is an important medicinal material with many functions in China. Flavonoids as the main secondary metabolites are a major class of medicinal components in "Hangju" and its composition and content can change significantly after flooding. This study mimicked the flooding stress of "Hangju" during flower bud differentiation and detected its metabolites in different growth stages. From widely targeted metabolomics data, 661 metabolites were detected, of which 46 differential metabolites exist simultaneously in the different growth stages of "Hangju". The top three types of the 46 differential metabolites were flavone C-glycosides, flavonol and flavone. Our results demonstrated that the accumulation of flavonoids in different growth stages of "Hangju" was different; however, quercetin, eriodictyol and most of the flavone C-glycosides were significantly enhanced in the two stages after flooding stress. The expression of key enzyme genes in the flavonoid synthesis pathway were determined using RT-qPCR, which verified the consistency of the expression levels of CHI, F3H, DFR and ANS with the content of the corresponding flavonoids. A regulatory network of flavonoid biosynthesis was established to illustrate that flooding stress can change the accumulation of flavonoids by affecting the expression of the corresponding key enzymes in the flavonoid synthesis pathway.


Assuntos
Chrysanthemum/química , Flavonoides/metabolismo , Flores/química , Metabolômica , China , Chrysanthemum/metabolismo , Flavonoides/uso terapêutico , Flores/metabolismo , Humanos , Medicina Tradicional Chinesa , Quercetina/metabolismo
9.
Int J Mol Sci ; 20(19)2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31581662

RESUMO

: Kidney stones affect 10% of the population. Yet, there is relatively little known about how they form or how to prevent and treat them. The claudin family of tight junction proteins has been linked to the formation of kidney stones. The flavonoid quercetin has been shown to prevent kidney stone formation and to modify claudin expression in different models. Here we investigate the effect of quercetin on claudin expression and localization in MDCK II cells, a cation-selective cell line, derived from the proximal tubule. For this study, we focused our analyses on claudin family members that confer different tight junction properties: barrier-sealing (Cldn1, -3, and -7), cation-selective (Cldn2) or anion-selective (Cldn4). Our data revealed that quercetin's effects on the expression and localization of different claudins over time corresponded with changes in transepithelial resistance, which was measured continuously throughout the treatment. In addition, these effects appear to be independent of PI3K/AKT signaling, one of the pathways that is known to act downstream of quercetin. In conclusion, our data suggest that quercetin's effects on claudins result in a tighter epithelial barrier, which may reduce the reabsorption of sodium, calcium and water, thereby preventing the formation of a kidney stone.


Assuntos
Claudinas/genética , Claudinas/metabolismo , Expressão Gênica , Quercetina/metabolismo , Junções Íntimas/metabolismo , Animais , Biomarcadores , Membrana Celular/metabolismo , Cães , Células Madin Darby de Rim Canino , Fosfatidilinositol 3-Quinases/metabolismo , Transporte Proteico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais
10.
J Food Sci ; 84(10): 2883-2897, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31553062

RESUMO

Quercetin is a hydrophobic flavonoid with high antioxidant activity. However, for biological applications, the bioavailability of quercetin is low due to physiological barriers. For this reason, an alternative is the protection of quercetin in matrices of biopolymers as zein. The objective of this work was to prepare and characterize quercetin-loaded zein nanoparticles by electrospraying and its study of in vitro bioavailability. The physicochemical parameters such as viscosity, density, and electrical conductivity of zein solutions showed a dependence of the ethanol concentration. In addition, rheological parameters demonstrated that solutions of zein in aqueous ethanol present Newtonian behavior, rebounding in the formation of nanoparticles by electrospraying, providing spherical, homogeneous, and compact morphologies, mainly at a concentration of 80% (v/v) of ethanol and of 5% (w/v) of zein. The size and shape of quercetin-loaded zein nanoparticles were studied by transmission electron microscopy (TEM), observing that it was entrapped, distributed throughout the nanoparticle of zein. Analysis by Fourier transform-infrared (FT-IR) of zein nanoparticles loaded with quercetin revealed interactions via hydrogen bonds. The efficacy of zein nanoparticles to entrap quercetin was particularly high for all quercetin concentration evaluated in this work (87.9 ± 1.5% to 93.0 ± 2.6%). The in vitro gastrointestinal release of trapped quercetin after 240 min was 79.1%, while that for free quercetin was 99.2%. The in vitro bioavailability was higher for trapped quercetin (5.9%) compared to free quercetin (1.9%), than of gastrointestinal digestion. It is concluded, that the electrospraying technique made possible the obtention of quercitin-loaded zein nanoparticles increasing their bioavailability. PRACTICAL APPLICATION: This type of nanosystems can be used in the food and pharmaceutical industry. Quercetin-loaded zein nanoparticles for its improvement compared to free quercetin can be used to decrease the prevalence of chronic degenerative diseases by increasing of the bioavailability of quercetin in the bloodstream. Other application can be as an antioxidant system in functional foods or oils to increase shelf life.


Assuntos
Composição de Medicamentos/métodos , Quercetina/química , Zeína/química , Antioxidantes/química , Antioxidantes/metabolismo , Disponibilidade Biológica , Biopolímeros/química , Linhagem Celular , Portadores de Fármacos/química , Composição de Medicamentos/instrumentação , Humanos , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Nanopartículas/química , Nanopartículas/metabolismo , Tamanho da Partícula , Quercetina/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier
11.
Am J Chin Med ; 47(6): 1307-1324, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31505936

RESUMO

Aloe vera ethanol extract (AVE) reportedly has significant anti-influenza virus activity, but its underlying mechanisms of action and constituents have not yet been completely elucidated. Previously, we have confirmed that AVE treatment significantly reduces the viral replication of green fluorescent protein-labeled influenza A virus in Madin-Darby canine kidney (MDCK) cells. In addition, post-treatment with AVE inhibited viral matrix protein 1 (M1), matrix protein 2 (M2), and hemagglutinin (HA) mRNA synthesis and viral protein (M1, M2, and HA) expressions. In this study, we demonstrated that AVE inhibited autophagy induced by influenza A virus in MDCK cells and also identified quercetin, catechin hydrate, and kaempferol as the active antiviral components of AVE. We also found that post-treatment with quercetin, catechin hydrate, and kaempferol markedly inhibited M2 viral mRNA synthesis and M2 protein expression. A docking simulation suggested that the binding affinity of quercetin, catechin hydrate, and kaempferol for the M2 protein may be higher than that of known M2 protein inhibitors. Thus, the inhibition of autophagy induced by influenza virus may explain the antiviral activity of AVE against H1N1 or H3N2. Aloe vera extract and its constituents may, therefore, be potentially useful for the development of anti-influenza agents.


Assuntos
Aloe/química , Antivirais , Autofagia/efeitos dos fármacos , Vírus da Influenza A/fisiologia , Vírus da Influenza A/patogenicidade , Extratos Vegetais/farmacologia , Replicação Viral/efeitos dos fármacos , Animais , Células Cultivadas , Cães , Hemaglutininas Virais/genética , Hemaglutininas Virais/metabolismo , Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A Subtipo H3N2 , Vírus da Influenza A/metabolismo , Rim/citologia , Ligação Proteica/efeitos dos fármacos , Quercetina/metabolismo , RNA Mensageiro/metabolismo , RNA Viral/metabolismo , Proteínas da Matriz Viral/metabolismo
12.
Drug Dev Ind Pharm ; 45(10): 1654-1663, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31382790

RESUMO

Objectives: The aim of the study was to deliver effective doses of quercetin (Que) to the lower region of hair follicles (HFs) using the transfollicular route through dipalmotylphosphatidylcholine (DPPC)-reinforced poly lactide-co- glycolide nanoparticles (DPPC-PLGA hybrid NPs) for the treatment of alopecia. Method: PLGA and DPPC-PLGA hybrid NPs were prepared by double-emulsification solvent evaporation method. NPs were characterized for size, shape, zeta potential entrapment and drug release. Drug-polymer interactions were determined by infrared spectroscopy (Fourier transform infrared spectroscopy, FTIR) and differential scanning calorimetry (DSC). Follicular uptake of fluorescent marker tagged NPs was assessed on isolated rat skin by fluorescent microscopy. Potential of hybrid NPs to induce hair regrowth was tested on testosterone-induced alopecia in rat models by visual inspection, hair follicular density measurement (no./mm), and histological skin tissue section studies. Key findings: Hybrid NPs had mean vesicles size 339 ± 1.6, zeta potential -32.6 ± 0.51, and entrapment efficiency 78 ± 5.5. Cumulative drug release after 12 h was found to be 47.27 ± 0.79%. FTIR and DSC confirmed that drug was independently dispersed in the amorphous form in the polymer. Data from fluorescence microscopy suggested that NPs were actively taken up by HFs. In-vivo studies on alopecia-induced rat models showed that hybrid NPs improved hair regrowth potential of Que and accumulation of NPs at HFs end region inhibit HFs cells apoptosis. Conclusion: This study concludes that phospholipid-polymer hybrid NPs could be the promising transfollicular delivery system for Que in the treatment of androgenic alopecia management.


Assuntos
Alopecia/tratamento farmacológico , Folículo Piloso/metabolismo , Nanopartículas/química , Fosfolipídeos/química , Polímeros/química , Quercetina/metabolismo , Quercetina/farmacologia , Animais , Varredura Diferencial de Calorimetria/métodos , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos/efeitos dos fármacos , Masculino , Tamanho da Partícula , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Ratos , Ratos Sprague-Dawley , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
13.
Appl Microbiol Biotechnol ; 103(19): 7953-7969, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31407037

RESUMO

Two sustainable and cost-effective cascade enzymatic systems were developed to regenerate uridine diphosphate (UDP)-α-D-glucose and UDP-ß-L-rhamnose from sucrose. The systems were coupled with the UDP generating glycosylation reactions of UDP sugar-dependent glycosyltransferase (UGT) enzymes mediated reactions. As a result, the UDP generated as a by-product of the GT-mediated reactions was recycled. In the first system, YjiC, a UGT from Bacillus licheniformis DSM 13, was used for transferring glucose from UDP-α-D-glucose to naringenin, in which AtSUS1 from Arabidopsis thaliana was used to synthesize UDP-α-D-glucose and fructose as a by-product from sucrose. In the second system, flavonol 7-O-rhamnosyltransferase (AtUGT89C1) from A. thaliana was used to transfer rhamnose from UDP-ß-L-rhamnose to quercetin, in which AtSUS1 along with UDP-ß-L-rhamnose synthase (AtRHM1), also from A. thaliana, were used to produce UDP-ß-L-rhamnose from the same starter sucrose. The established UDP recycling system for the production of naringenin glucosides was engineered and optimized for several reaction parameters that included temperature, metal ions, NDPs, pH, substrate ratio, and enzymes ratio, to develop a highly feasible system for large-scale production of different derivatives of naringenin and other natural products glucosides, using inexpensive starting materials. The developed system showed the conversion of about 37 mM of naringenin into three different glucosides, namely naringenin, 7-O-ß-D-glucoside, naringenin, 4'-O-ß-D-glucoside, and naringenin, 4',7-O-ß-D-diglucoside. The UDP recycling (RCmax) was 20.10 for naringenin glucosides. Similarly, the conversion of quercetin to quercetin 7-O-α-L-rhamnoside reached a RCmax value of 10.0.


Assuntos
Flavanonas/metabolismo , Glucosídeos/metabolismo , Glucuronosiltransferase/metabolismo , Hexosiltransferases/metabolismo , Quercetina/metabolismo , Sacarose/metabolismo , Arabidopsis/enzimologia , Bacillus licheniformis/enzimologia , Biocatálise , Glucuronosiltransferase/isolamento & purificação , Hexosiltransferases/isolamento & purificação
14.
Artigo em Inglês | MEDLINE | ID: mdl-31401083

RESUMO

To identify the effects of poplar secondary metabolites on Lymantria dispar, six poplar secondary metabolites (i.e., caffeic acid, salicin, rutin, quercetin, flavone, and catechol) and three mixtures containing characteristic secondary metabolites in poplar were selected. Mixture 1 contained flavone and salicin, mixture 2 contained salicin, caffeic acid, and catechol, and mixture 3 contained flavone, catechol, and caffeic acid. Mixtures were added to artificial diets used to feed 2nd instar L. dispar larvae. The effects of different secondary metabolites on larval growth and development, antifeedant activity, nutrient utilization, and detoxifying enzymatic activity were investigated. Results revealed that there were different influences on L. dispar larvae. The maximum antifeedant rate of flavone was 87.58%. Larvae treated with mixture 2 had a significantly longer development time of 5.61 d with a survival rate of 38.75% for 15 d, which is lower than a single secondary metabolite. No L. dispar larvae survived on feeding diets containing flavone for 7 d. An increase in GST and P450 activities in larvae was significantly induced during the 72 h feeding on artificial diets containing experimental secondary metabolites. After treatment containing salicin and flavone for 24-72 h, P450 activity increased at first then decreased. These results provide a foundation for further investigation on the host selection and underlying adaptation mechanisms in L. dispar.


Assuntos
Inibidores Enzimáticos/metabolismo , Larva/enzimologia , Larva/crescimento & desenvolvimento , Lepidópteros/enzimologia , Lepidópteros/crescimento & desenvolvimento , Animais , Álcoois Benzílicos/metabolismo , Ácidos Cafeicos/metabolismo , Catecóis/metabolismo , Flavonas/metabolismo , Glucosídeos/metabolismo , Populus/metabolismo , Quercetina/metabolismo , Rutina/metabolismo , Metabolismo Secundário
15.
J Sci Food Agric ; 99(15): 6931-6936, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31393606

RESUMO

BACKGROUND: The effects of ultraviolet B (UV-B) radiation on plants are well known and have recently attracted a great deal of attention due to the production of large quantities of secondary metabolites, which are very beneficial for human health. Recent studies have demonstrated the possibility of exploiting UV-B radiation to induce metabolic changes in fruit, vegetables, and herbs. The role of UV-B rays in inducing secondary plant metabolites is enhanced by new plastic films, which, as a result of their optical properties, permit the necessary dosage of UV-B to be transmitted into the greenhouse to stimulate such metabolites without altering the harvest. RESULTS: The main goal of the present paper is to demonstrate that, by using a greenhouse plastic film with appropriate transmittance of UV-B for rocket salad cultivation, it is possible to increase the nutraceutical elements in comparison with the same species grown in absence of such radiation. Tests compared nutritional elements extracted from rocket salad grown under greenhouses covered with several plastic films differing in UV-B transmittance. We found that rocket salad grown under plastic with 27% UV-B transmittance exhibited very high luteolin and quercetin content in comparison with rocket salad cultivated under film blocking UV-B radiation. CONCLUSIONS: Our experimental results confirm the possibility of exploiting UV-B radiation in the correct amounts by appropriate greenhouse plastic covers, to produce natural 'medicines' using the plants and to satisfy increasing consumer demand for natural health-promoting food products. © 2019 Society of Chemical Industry.


Assuntos
Produção Agrícola/métodos , Plantas Medicinais/crescimento & desenvolvimento , Verduras/crescimento & desenvolvimento , Produção Agrícola/instrumentação , Frutas/química , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Luteolina/análise , Luteolina/metabolismo , Plantas Medicinais/química , Plantas Medicinais/metabolismo , Plantas Medicinais/efeitos da radiação , Plásticos/análise , Quercetina/análise , Quercetina/metabolismo , Raios Ultravioleta , Verduras/química , Verduras/metabolismo , Verduras/efeitos da radiação
16.
Med Sci Monit ; 25: 5795-5800, 2019 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-31377749

RESUMO

BACKGROUND Sepsis is a severe medical condition. Approximately 0.75 million people are diagnosed with sepsis in the USA annually. Several of anti-inflammatory drugs are used to manage sepsis, but with a very low success rate. This study examined the possible protective effects of a naturally occurring flavanone, quercetin, in a rat model of sepsis. MATERIAL AND METHODS The study was carried out using Wistar albino rats. Sepsis was induced by cecal ligation and puncture methods. Histological analysis was performed by hematoxylin and eosin (HE) staining. Reactive oxygen species (ROS) levels were determined by flow cytometery. Superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX) activities were determined by standard assays. Protein expression was determined by Western blot analysis. RESULTS The results showed that quercetin reduced the tissue edema, congestion, and hemorrhage, increased the alveolar volume, and helped to maintain the lung anatomy of septic rats. Admistration of quercetin at the dosage of 15 and 20 mg/kg to septic rats caused significant reduction in the ROS levels. The activities and the expression of SOD, CAT, and APX were significantly decreased upon administration of quercetin in the septic rats at the dosage of 15 and 20 mg/kg. The effects of quercetin were also examined on the expression of the High mobility group box 1 (HMGB1) protein in septic rats. The results showed that quercetin caused a significant decrease in HMGB1 protein levels. CONCLUSIONS The findings of this study suggest that quercetin has therapeutic potential in the treatment of sepsis.


Assuntos
Quercetina/uso terapêutico , Sepse/tratamento farmacológico , Animais , Anti-Inflamatórios/uso terapêutico , Ascorbato Peroxidases/metabolismo , Catalase/metabolismo , Modelos Animais de Doenças , Flavanonas/farmacologia , Flavanonas/uso terapêutico , Proteína HMGB1/metabolismo , Masculino , Quercetina/metabolismo , Quercetina/farmacologia , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Sepse/fisiopatologia , Superóxido Dismutase/metabolismo
17.
AAPS PharmSciTech ; 20(6): 250, 2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-31297635

RESUMO

Melanoma is regarded as the fifth and sixth most common cancer in men and women, respectively, and it is estimated that one person dies from melanoma every hour in the USA. Unfortunately, the treatment of melanoma is difficult because of its aggressive metastasis and resistance to treatment. The treatment of melanoma continues to be a challenging issue due to the limitations of available treatments such as a low response rate, severe adverse reactions, and significant toxicity. Natural polyphenols have attracted considerable attention from the scientific community due to their chemopreventive and chemotherapeutic efficacy. It has been suggested that poorly soluble polyphenols such as curcumin, resveratrol, quercetin, coumarin, and epigallocatechin-3-gallate may have significant benefits in the treatment of melanoma due to their antioxidant, anti-inflammatory, antiproliferative, and chemoprotective efficacies. The major obstacles for the use of polyphenolic compounds are low stability and poor bioavailability. Numerous nanoformulations, including solid lipid nanoparticles, polymeric nanoparticles, micelles, and liposomes, have been formulated to enhance the bioavailability and stability, as well as the therapeutic efficacy of polyphenols. This review will provide an overview of poorly soluble polyphenols that have been reported to have antimetastatic efficacy in melanomas.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Melanoma/tratamento farmacológico , Polifenóis/administração & dosagem , Polifenóis/química , Neoplasias Cutâneas/tratamento farmacológico , Animais , Antioxidantes/administração & dosagem , Antioxidantes/química , Antioxidantes/metabolismo , Disponibilidade Biológica , Catequina/administração & dosagem , Catequina/análogos & derivados , Catequina/química , Catequina/metabolismo , Curcumina/administração & dosagem , Curcumina/química , Curcumina/metabolismo , Humanos , Melanoma/metabolismo , Melanoma/prevenção & controle , Nanopartículas/administração & dosagem , Nanopartículas/química , Nanopartículas/metabolismo , Polifenóis/metabolismo , Quercetina/administração & dosagem , Quercetina/química , Quercetina/metabolismo , Resveratrol/administração & dosagem , Resveratrol/química , Resveratrol/metabolismo , Neoplasias Cutâneas/metabolismo , Solubilidade
18.
J Agric Food Chem ; 67(31): 8609-8616, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31314514

RESUMO

Quercetin (QUE)-loaded nanoparticles (QCG-NPs) were fabricated by ionic gelation between chitosan (CS) and gum arabic (GA) at pH 3.5. At constant CS (0.5 mg/mL) and QUE (60 µM) concentrations, QCG-NPs (260-490 nm) were prepared uniformly with 0.8-2.2 mg/mL GA and exhibited high QUE encapsulation efficiency (94.8-98.0%) and sustained QUE release (4.42-8.89% after 8 h). Because of the electrostatic interaction between QCG-NPs and the mucin layer, in vitro mucin and cell adhesion of QUE were significantly (p < 0.05) enhanced in QCG-NPs (0.44-0.48 mg/mL and 31.7-78.5%), respectively, and the adhesiveness was significantly (p < 0.05) increased with an increase of GA. Because particle size and adhesion properties affect the surface area and retention time of QCG-NPs at the absorption site, cell permeation of QUE through simple diffusion by QCG-NPs exhibited the same tendency as the adhesion results. These data were verified in cellular antioxidant and in vivo ferric reducing abilities of plasma assays that evaluated the antioxidant activities of QUE absorbed into an intestinal cell model and rat blood, respectively. The results provide a better understanding of QCG-NP absorption and indicate that QCG-NPs with mucoadhesion properties can be an effective delivery system for improving QUE absorption.


Assuntos
Antioxidantes/química , Quitosana/química , Sistemas de Liberação de Medicamentos/métodos , Mucosa Intestinal/metabolismo , Nanopartículas/química , Quercetina/química , Quercetina/metabolismo , Animais , Antioxidantes/administração & dosagem , Antioxidantes/metabolismo , Células CACO-2 , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/instrumentação , Humanos , Tamanho da Partícula , Quercetina/administração & dosagem , Ratos , Ratos Sprague-Dawley
19.
Int J Mol Sci ; 20(11)2019 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31159151

RESUMO

Quercetin is an abundant flavonoid in nature and is used in several dietary supplements. Although quercetin is extensively metabolized by human enzymes and the colonic microflora, we have only few data regarding the pharmacokinetic interactions of its metabolites. Therefore, we investigated the interaction of human and microbial metabolites of quercetin with the xanthine oxidase enzyme. Inhibitory effects of five conjugates and 23 microbial metabolites were examined with 6-mercaptopurine and xanthine substrates (both at 5 µM), employing allopurinol as a positive control. Quercetin-3'-sulfate, isorhamnetin, tamarixetin, and pyrogallol proved to be strong inhibitors of xanthine oxidase. Sulfate and methyl conjugates were similarly strong inhibitors of both 6-mercaptopurine and xanthine oxidations (IC50 = 0.2-0.7 µM); however, pyrogallol inhibited xanthine oxidation (IC50 = 1.8 µM) with higher potency vs. 6-MP oxidation (IC50 = 10.1 µM). Sulfate and methyl conjugates were approximately ten-fold stronger inhibitors (IC50 = 0.2-0.6 µM) of 6-mercaptopurine oxidation than allopurinol (IC50 = 7.0 µM), and induced more potent inhibition compared to quercetin (IC50 = 1.4 µM). These observations highlight that some quercetin metabolites can exert similar or even a stronger inhibitory effect on xanthine oxidase than the parent compound, which may lead to the development of quercetin-drug interactions (e.g., with 6-mercaptopurin or azathioprine).


Assuntos
Quercetina/análogos & derivados , Quercetina/farmacologia , Xantina Oxidase/antagonistas & inibidores , Alopurinol/química , Alopurinol/farmacologia , Catálise , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Humanos , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Oxirredução , Ligação Proteica , Quercetina/química , Quercetina/metabolismo , Relação Estrutura-Atividade , Xantina/química , Xantina/farmacologia
20.
Fitoterapia ; 137: 104191, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31163200

RESUMO

8,2'-Diprenylquercetin 3-methyl ether, a natural product with prominent anti-breast cancer activity, is the main active constituent of Sinopodophylli Fructus. A high-performance liquid chromatography with a diode array detector coupled with electrospray ionization ion trap time-of-flight multistage mass spectrometry (HPLC-DAD-ESI-IT-TOF-MSn) method was established and applied to profile and identify the metabolites of 8,2'-diprenylquercetin 3-methyl ether as well as study their distribution in rat organs for the first time. A total of 100 new metabolites were tentatively identified in rats. The metabolic reactions of 8,2'-diprenylquercetin 3-methyl ether in rats in vivo were hydroxylation, methylation, glucuronidation, dehydrogenation, sulfation, polymerization and cysteine conjugation as well as the specific reactions of leucine/isoleucine, proline, and vitamin C conjugation. The detected metabolites included 77 in faeces, 50 in urine, 11 in plasma, 50 in the small intestine, 32 in the stomach, 23 in the liver, 9 in the lungs, 9 in the spleen, 8 in the heart, and 6 in the kidneys. The results indicated that the small intestine, stomach, and liver were the major organs for the distribution of 8,2'-diprenylquercetin 3-methyl ether metabolites. Furthermore, 27 metabolites showed various bioactivities predicted by the analysis of "PharmMapper", among which 9 metabolites showed anti-cancer activity. These results are very useful for understanding the metabolism and pharmacological actions as well as the effective forms and toxic actions of 8,2'-diprenylquercetin 3-methyl ether in vivo; moreover, they will lay the foundation for further studies on the metabolism of prenylflavonoid compounds.


Assuntos
Quercetina/análogos & derivados , Animais , Berberidaceae/química , Cromatografia Líquida de Alta Pressão , Frutas/química , Masculino , Estrutura Molecular , Quercetina/metabolismo , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas por Ionização por Electrospray , Distribuição Tecidual
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