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1.
Food Chem ; 336: 127717, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32763740

RESUMO

Continued industrialization and increasing environmental problems have highlighted the need to research new eco-friendly solvents, also known as deep eutectic solvents (DESs). To implement these solvents in industrial processes, the knowledge of their molecular organization and thermophysical properties must be enhanced. In this work, two DESs have been characterized: d-glucose:choline chloride:water (GCH) and d-glucose:citric acid:water (GCiH). NMR techniques were used to analyse both the supramolecular structure and the role of water and to calculate the diffusion coefficients. Moreover, seven thermophysical properties at several temperatures were evaluated. As a second aim, the solubility of quercetin was determined. NMR studies showed a stronger supramolecular structure of GCH and a high ratio of ß-glucose in both DESs. Based on the thermophysical results, the solvent with choline chloride had the most compact fluid structure. Finally, the solubility of quercetin in the DESs was higher than in water, especially for GCH.


Assuntos
Glucose/química , Solventes/química , Colina/química , Ácido Cítrico/química , Espectroscopia de Ressonância Magnética , Quercetina/química , Solubilidade , Temperatura , Termodinâmica , Água/química
2.
Food Chem ; 335: 127556, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32738529

RESUMO

We investigated the interactions of two main phenolics, rutin and quercetin, with starch, the primary component of Tartary buckwheat. The addition of rutin or quercetin significantly affected the structural and physicochemical properties of the starch, and rutin showed a stronger effect than quercetin, particularly at a dose of 6% (w/w). Rutin better enhanced the aggregation of starch pastes and gel formation than quercetin according to our pasting, rheological and thermal property analyses. A scanning electron microscopy analysis of its morphology showed that rutin was more easily dispersed in starchy matrix than quercetin and acted as rigid fillers for gels. The nuclear magnetic resonance results showed different binding sites due to the steric hindrance of the rutin disaccharide groups (rutinose). These findings provide fundamental information about applying rutin during the whole grain processing of Tartary buckwheat.


Assuntos
Fagopyrum/química , Quercetina/química , Reologia , Rutina/química , Amido/química
3.
Food Chem ; 334: 127508, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32711265

RESUMO

Quercetin, a potential polyphenolic which possesses several biological effects. The influenza virus polymerase basic 2 (PB2) subunit of RNA polymerase responsible for replication, degree of virus conservation and active target site for designing specific antivirals. The quercetin derivatives downloaded from PubChem were screened using PyRX software configured with Vina Wizard, targeted on cap-binding site of the PB2 of influenza viral RNA polymerase. Among the PubChem library (total 97,585,747 compounds), 410 quercetin derivatives were screened using molecular docking (affinity: <-9.0 kcal) for their drug-likeness and in vitro cytopathic effect by Sulforhodamine B (SRB) assay. Among all quercetin derivatives, quercetin 3'-glucuronide (Q3G) showed strongest binding affinity towards cap-binding site of the PB2 subunit with -9.6 kcal of binding affinity and 0.00054 mM of Ki value, while quercetin 3'-glucuronide (Q7G) was presented highest anti-influenza activity with 2.10 ± 0.05 of IC50 on influenza A/PR/8/34 virus and non-cytotoxic effect as CC50 > 100 µg/mL.


Assuntos
Antivirais/farmacologia , Vírus da Influenza A/efeitos dos fármacos , Quercetina/análogos & derivados , Animais , Antivirais/química , Antivirais/metabolismo , Sítios de Ligação , Sobrevivência Celular/efeitos dos fármacos , RNA Polimerases Dirigidas por DNA/química , RNA Polimerases Dirigidas por DNA/metabolismo , Cães , Humanos , Vírus da Influenza A/enzimologia , Influenzavirus B/efeitos dos fármacos , Células Madin Darby de Rim Canino , Simulação de Acoplamento Molecular , Estrutura Terciária de Proteína , Subunidades Proteicas/química , Subunidades Proteicas/metabolismo , Quercetina/química , Quercetina/metabolismo , Quercetina/farmacologia , Termodinâmica
4.
Food Chem ; 336: 127714, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32828014

RESUMO

Five new flavonoids (1-5), along with 25 known compounds, were isolated from the rhizomes of Potentilla anserina L. and their structures were identified using spectroscopic and chemical evidence. The extract, all fractions, and all isolated compounds were evaluated for their antioxidant, α-glucosidase, and tyrosinase inhibitory activities, and their structure-activity relationship was interpreted. The biflavanols and quercetin-3-O-α-l-rhamnopyranoside-2″-gallate (14) exhibited significant antioxidant and α-glucosidase inhibition activities. In this study, anti-tyrosinase activity and its mechanism of active compounds (potenserin C (4), potenserin D (5), and quercetin-3-O-α-l-rhamnopyranoside-2″-gallate (14)) were explored by a combination of computational simulations and kinetic studies. Kinetic studies indicated that potenserin C (4) and quercetin-3-O-α-l-rhamnopyranoside-2″-gallate (14) inhibited tyrosinase in a competitive manner, whereas potenserin D (5) acted in a reversible noncompetitive manner. The molecular docking result indicated that the substitution of the glucose moiety with galloyl and the presence of 3', 4', 5'-OH in flavonoid aglycones played a crucial role for the tyrosinase inhibiting effect. Moreover, the presence of biflavanols increased the activity against tyrosinase because of strong hydrogen binding, π-alkyl binding, and electrostatic interaction. Thus, the presented experiments developed several new lead compounds that could act as antioxidants and α-glucosidase inhibitors. Furthermore, biflavanols and quercetin-3-O-α-l-rhamnopyranoside-2″-gallate played important roles in the anti-browning activity during food processing.


Assuntos
Antioxidantes/farmacologia , Inibidores de Glicosídeo Hidrolases/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , Potentilla/química , Relação Estrutura-Atividade , Antioxidantes/química , Avaliação Pré-Clínica de Medicamentos , Flavonoides/química , Flavonoides/farmacologia , Inibidores de Glicosídeo Hidrolases/química , Glicosídeos/química , Glicosídeos/farmacologia , Cinética , Simulação de Acoplamento Molecular , Monofenol Mono-Oxigenase/metabolismo , Extratos Vegetais/química , Quercetina/análogos & derivados , Quercetina/química , Quercetina/farmacologia , Rizoma/metabolismo
5.
Int J Nanomedicine ; 15: 5963-5975, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32884259

RESUMO

Background: Previous studies have reported that quercetin (Q) has a potential antibacterial and anticancer activity. However, its application is limited by many important factors including high hydrophobicity and low absorption. Methodology: In the current study, we synthesized and characterized (Patent) a novel chitosan-based quercetin nanohydrogel (ChiNH/Q). Encapsulation efficiency was confirmed by UV/VIS spectrophotometer. Physicochemical characterization of ChiNH/Q was assessed by PDI, DLS, SEM, FTIR, and XRD. The toxicity of the ChiNH/Q against five strains of the pathogen and HepG2 cells was examined. Moreover, the quantification of ChiNH/Q on genomic global DNA methylation and expression of DNMTs (DNMT1/3A/3B) in HepG2 cancer cells were evaluated by ELISA and real-time PCR, respectively. Results: Under the SEM-based images, the hydrodynamic size of the ChiNH/Q was 743.6 nm. The changes in the PDI were 0.507, and zeta potential was obtained as 12.1 mV for ChiNH/Q. The FTIR peak of ChiNH/Q showed the peak at 627 cm-1 corresponded to tensile vibrational of NH2-groups related to Q, and it is the indication of Q loading in the formulation. Moreover, XRD data have detected the encapsulation of ChiNH/Q. The ChiNH/Q showed a potent antimicrobial inhibitory effect and exerted cytotoxic effects against HepG2 cancer cells with IC50 values of 100 µg/mL. Moreover, our data have shown that ChiNH/Q effectively reduced (65%) the average expression level of all the three DNMTs (p<0.05) and significantly increased (1.01%) the 5-methylated cytosine (5-mC) levels in HepG2 cells. Conclusion: Our results showed for the first time the bioavailability and potentiality of ChiNH/Q as a potent antimicrobial and anticancer agent against cancer cells. Our result provided evidence that ChiNH/Q could effectively reduce cellular DNMT expression levels and increase genomic global DNA methylation in HepG2 cancer cells. Our results suggest a potential clinical application of nanoparticles as antimicrobial and anticancer agents in combination cancer therapy.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Epigênese Genética/efeitos dos fármacos , Hidrogéis/química , Nanoestruturas/química , Quercetina/farmacologia , Anti-Infecciosos/administração & dosagem , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacocinética , Quitosana/química , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , DNA (Citosina-5-)-Metiltransferases/metabolismo , Células Hep G2 , Humanos , Hidrogéis/administração & dosagem , Interações Hidrofóbicas e Hidrofílicas , Testes de Sensibilidade Microbiana , Nanoestruturas/administração & dosagem , Quercetina/administração & dosagem , Quercetina/química , Quercetina/farmacocinética , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
6.
Front Immunol ; 11: 1451, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32636851

RESUMO

Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) represents an emergent global threat which is straining worldwide healthcare capacity. As of May 27th, the disease caused by SARS-CoV-2 (COVID-19) has resulted in more than 340,000 deaths worldwide, with 100,000 deaths in the US alone. It is imperative to study and develop pharmacological treatments suitable for the prevention and treatment of COVID-19. Ascorbic acid is a crucial vitamin necessary for the correct functioning of the immune system. It plays a role in stress response and has shown promising results when administered to the critically ill. Quercetin is a well-known flavonoid whose antiviral properties have been investigated in numerous studies. There is evidence that vitamin C and quercetin co-administration exerts a synergistic antiviral action due to overlapping antiviral and immunomodulatory properties and the capacity of ascorbate to recycle quercetin, increasing its efficacy. Safe, cheap interventions which have a sound biological rationale should be prioritized for experimental use in the current context of a global health pandemic. We present the current evidence for the use of vitamin C and quercetin both for prophylaxis in high-risk populations and for the treatment of COVID-19 patients as an adjunct to promising pharmacological agents such as Remdesivir or convalescent plasma.


Assuntos
Antivirais/uso terapêutico , Ácido Ascórbico/uso terapêutico , Betacoronavirus/fisiologia , Infecções por Coronavirus/prevenção & controle , Fatores Imunológicos/uso terapêutico , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Profilaxia Pré-Exposição/métodos , Quercetina/uso terapêutico , Animais , Antivirais/efeitos adversos , Antivirais/química , Antivirais/farmacocinética , Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/virologia , Sinergismo Farmacológico , Quimioterapia Combinada , Humanos , Camundongos , Pneumonia Viral/virologia , Quercetina/efeitos adversos , Quercetina/química , Quercetina/farmacocinética , Replicação Viral/efeitos dos fármacos
7.
Biochem Pharmacol ; 178: 114123, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32593613

RESUMO

Commonly used drugs for treating many conditions are either natural products or derivatives. In silico modelling has identified several natural products including quercetin as potential highly effective disruptors of the initial infection process involving binding to the interface between the SARS-CoV-2 (Covid-19) Viral Spike Protein and the epithelial cell Angiotensin Converting Enzyme-2 (ACE2) protein. Here we argue that the oral route of administration of quercetin is unlikely to be effective in clinical trials owing to biotransformation during digestion, absorption and metabolism, but suggest that agents could be administered directly by alternative routes such as a nasal or throat spray.


Assuntos
Betacoronavirus/efeitos dos fármacos , Produtos Biológicos/farmacologia , Peptidil Dipeptidase A/metabolismo , Quercetina/farmacologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Betacoronavirus/metabolismo , Betacoronavirus/fisiologia , Produtos Biológicos/administração & dosagem , Produtos Biológicos/química , Ensaios Clínicos como Assunto/métodos , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/virologia , Avaliação Pré-Clínica de Medicamentos/métodos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Estrutura Molecular , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Pneumonia Viral/virologia , Ligação Proteica/efeitos dos fármacos , Quercetina/administração & dosagem , Quercetina/química , Internalização do Vírus/efeitos dos fármacos
8.
BMC Complement Med Ther ; 20(1): 105, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32245457

RESUMO

BACKGROUND: Cissus quadrangularis Linn. (CQ) has been used in Indian and Thai traditional medicine for healing bone fractures because of numerous active ingredients in CQ. It is still unclear which compounds are the active ingredients for bone formation. METHODS: The molecular docking technique, the ethanolic extraction along with hexane fractionation, and an in vitro experiment with a human osteoblast cell line (MG-63) were used to narrow down the active compounds, to prepare the CQ extract, and to test biological activities, respectively. RESULTS: The molecular docking technique revealed that quercetin and ß-sitosterol had highest and lowest potential to bind to estrogen receptors, respectively. Compared to the crude ethanol extract (P1), the ethanolic fraction (P2) was enriched with rutin and quercetin at 65.36 ± 0.75 and 1.06 ± 0.12 mg/g, respectively. Alkaline phosphatase (ALP) activity was significantly enhanced in osteoblasts exposed to the P2 in both tested concentrations. The amount of hydroxyproline was slightly increased in the P1 treatment, while osteocalcin was inhibited. Moreover, the P2 significantly activated osteoprotegerin (OPG) and inhibited receptor activator of nuclear factor κ ligand (RANKL) expression. CONCLUSIONS: Taken together, the enriched rutin and quercetin fraction of CQ triggered the molecules involved in bone formation and the molecules inhibiting bone resorption.


Assuntos
Reabsorção Óssea/tratamento farmacológico , Cissus/química , Osteogênese/efeitos dos fármacos , Extratos Vegetais/farmacologia , Quercetina/farmacologia , Rutina/farmacologia , Sitosteroides/farmacologia , Linhagem Celular , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Extratos Vegetais/química , Quercetina/química , Rutina/química , Sitosteroides/química
9.
Food Chem ; 319: 126562, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32155536

RESUMO

This study investigated the effects of the addition of onion waste fractions into gluten-free (GF) bread to promote its health benefits. 5% of the control (C) GF flour blend was replaced with three waste fractions in the form of: fried onion (FO), dried onion (DO) and onion peel (OP). Antioxidant activity, content of flavonols and total polyphenols of breads increased in the following order: C < FO < DO < OP. No differences were observed in sensory analysis. We found that quercetin glycosides, dimers and trimer in OP-bread, determined according to their mass spectra, decomposed during baking and released free quercetin, which points to their thermal instability. Cross-over study revealed that consumption of OP-bread significantly increased (p < 0.05) antioxidant activity of consumers' blood compared to control bread consumption, indicating good bioavailability of flavonols. Results suggest incorporation of OP into GF bread can increase its biological value with satisfactory sensory acceptance.


Assuntos
Pão/análise , Cebolas/química , Cebolas/metabolismo , Disponibilidade Biológica , Culinária , Estudos Cross-Over , Polifenóis/química , Polifenóis/metabolismo , Quercetina/química , Quercetina/metabolismo , Rutina/química , Rutina/metabolismo
10.
Life Sci ; 253: 117584, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32220623

RESUMO

Accumulating recent studies have demonstrated the preventive and therapeutic effects of polyphonic compounds such as quercetin in colorectal cancer. Therefore, we aimed to evaluate the underlying mechanisms for positive effects of quercetin in rats with 1,2-dimethylhydrazine (DMH)- induced colorectal cancer. For this purpose, male Wistar rats were classified as 6 groups, including group 1 without any intervention, group 2 as quercetin received rats (50 mg/kg), groups 3 as DMH received rats (20 mg/kg) group 4-6 DMH and quercetin received rats. DNA damage, DNA repair, the expression levels and activities of enzymic antioxidants, non-enzymic antioxidants, and NRF2/Keap1 signaling were evaluated in colon tissues of all groups. Our results showed significant suppression of DNA damage and induction of DNA repair in DMH + Quercetin groups, particularly in entire-period in comparison to other groups (p < .05). The expression levels and activities of enzymic and non-enzymic antioxidants were increased in DMH + Quercetin groups (p < .05). Lipid and protein peroxidation were significantly suppressed in DMH + Quercetin groups (p < .05). In addition, quercetin also modulated NRF2/Keap1 signaling and its targets, detoxifying enzymes in DMH + Quercetin groups. Our finding demonstrated that quercetin supplementation effectively reversed DMH-mediated oxidative stress and DNA damage through targeting NRF2/Keap1 signaling pathway.


Assuntos
1,2-Dimetilidrazina/metabolismo , Carcinógenos/metabolismo , Neoplasias do Colo/tratamento farmacológico , Fator 2 Relacionado a NF-E2/metabolismo , Quercetina/química , 1,2-Dimetilidrazina/toxicidade , Animais , Antioxidantes/química , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Carcinógenos/química , Carcinógenos/toxicidade , Catalase/metabolismo , Dano ao DNA/efeitos dos fármacos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Lipídeos/química , Masculino , Neoplasias Experimentais , Estresse Oxidativo/efeitos dos fármacos , Quercetina/metabolismo , Quercetina/farmacologia , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio , Transdução de Sinais
11.
Phytomedicine ; 69: 153185, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32120244

RESUMO

BACKGROUND: Dihydroquercetin (DHQ) is an antifibrotic agent. However, whether DHQ can prevent renal fibrosis remains unknown. PURPOSE: This study aimed to investigate the effects of DHQ on tubulointerstitial fibrosis and its underlying mechanisms in unilateral ureteral obstruction (UUO) mice in vivo and NRK-49F cells in vitro. METHODS: In vivo, UUO mice received vehicle or DHQ treatment. In vitro, NRK-49F cells were pretreated with DHQ and exposed to transforming growth factor-ß1 (TGF-ß1). Changes in fibroblast activation, collagen synthesis, oxidative stress, and related signaling pathways were assessed by immunohistochemical staining, Western blot analysis, real-time reverse transcription-PCR, and fluorescence microscopy. RESULTS: UUO induced tubular atrophy, inflammation, fibroblast differentiation into myofibroblast, and collagen deposition, whereas DHQ ameliorated these effects. UUO also resulted in decreased levels of nuclear factor-erythroid-2-related factor 2 (Nrf2), catalase, and heme oxygenase-1, but increased H2O2 and malondialdehyde levels. DHQ treatment corrected these changes. In vitro, the intracellular Nrf2 level of NRK-49F exposed to TGF-ß1 decreased. However, DHQ rescued intracellular Nrf2 level and promoted nuclear translocation of Nrf2. DHQ scavenged TGF-ß1-induced accumulation of reactive oxygen species, inhibited TGF-ß1-induced Smad3 phosphorylation, and prevented TGF-ß1-induced fibroblast activation and collagen synthesis in NRK-49F. Nrf2 knockdown could suppress the DHQ-mediated inhibitory effects on oxidative stress, Smad3 phosphorylation, fibroblast activation, and collagen deposition. Furthermore, DHQ ameliorated established renal fibrosis in UUO mice. CONCLUSIONS: DHQ posed remarkable preventive and therapeutic effects on UUO-induced renal fibrosis and suppressed fibroblast activation by reducing oxidative stress and Smad3 phosphorylation via Nrf2 signaling. This study provided a mechanistic basis for the clinical application of DHQ in renal fibrosis treatment.


Assuntos
Nefropatias/tratamento farmacológico , Fator 2 Relacionado a NF-E2/metabolismo , Substâncias Protetoras/farmacologia , Quercetina/análogos & derivados , Transdução de Sinais/efeitos dos fármacos , Animais , Fibrose , Peróxido de Hidrogênio/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Nefropatias/metabolismo , Nefropatias/patologia , Masculino , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/genética , Estresse Oxidativo/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Quercetina/química , Quercetina/farmacologia , Ratos , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Obstrução Ureteral/metabolismo , Obstrução Ureteral/patologia
12.
J Food Sci ; 85(4): 1090-1097, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32147833

RESUMO

This work aims to evaluate the quality of seven varieties of Zanthoxylum bungeanum peels based on phenolic compounds, bioactivity, and HPLC fingerprint combined with chemometrics analysis, and pick out the key chemical compounds. As a result, S2 (Fengxian Dahongpao) showed the highest content of total phenolic and rutin, as well as the strongest antioxidant activity, followed by S6 (Hancheng Shizitou). From HPLC fingerprint, eight common characteristic peaks were selected and proved to be effective in controlling the quality of Z. bungeanum peels with the total contribution of 92.775%. The similarity values of each sample ranged between 0.696 and 0.970. In addition, hyperoside was identified as another key chemical indicator for quality evaluation of Z. bungeanum peels by PCA. Accordingly, seven varieties of Z. bungeanum were classified into four groups, among which group 4 (Fengxian Dahongpao, S2) was considered as an outstanding variety, followed by group 1 (S5, S6, and S7) and group 3 (S3 and S4), and group 2 (Fugu late-maturing, S1) was the last one. These results will be helpful to establish an effective and comprehensive evaluation system of Z. bungeanum. PRACTICAL APPLICATION: This study not only provides another index for quality evaluation of Z. bungeanum peels, but it also expects to be a theoretical basis for high-quality germplasm cultivation and the development of Z. bungeanum peels as food additives, pharmaceutical, or health care products.


Assuntos
Fenóis/química , Extratos Vegetais/química , Zanthoxylum/química , Cromatografia Líquida de Alta Pressão , Quercetina/análogos & derivados , Quercetina/química , Rutina/química , Zanthoxylum/classificação
13.
Food Chem ; 318: 126414, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32135419

RESUMO

In this study, the effects of citrus flavonoids naringin (NAR), neohesperidin (NEO) and quercetin (QUER) on aflatoxins accumulation by a selected Aspergillus parasiticus strain in maize at 0.95 aw were studied by response surface methodology using a Box-Behnken design. Multiple response optimization was applied to simultaneously minimize the contamination with aflatoxins (AFs) B1, G1, B2 and G2. The application of the optimal mixture in maize at 0.95 aw (0.39 mM NAR, 0.24 mM NEO and 0.40 mM QUER) reduced from 85% to 100% AFs accumulation. The same mixture at 0.98 aw, led to a reduction in AFs accumulation that ranged from 93% to 98%. Ultrastructure alterations of cellular membranes and walls in A. parasiticus, evidenced by transmission electron microscopy images, were severe and depended on the type of flavonoid and their combination. Flavonoid mixtures may provide an environmentally friendly alternative for decreasing AFs accumulation in stored maize, replacing synthetic compounds.


Assuntos
Aflatoxinas/metabolismo , Aspergillus/fisiologia , Parede Celular/ultraestrutura , Citrus/química , Flavonoides/química , Zea mays/metabolismo , Aflatoxinas/química , Citrus/metabolismo , Flavanonas/química , Microscopia Eletrônica de Transmissão , Quercetina/química , Zea mays/microbiologia
14.
Molecules ; 25(6)2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32204461

RESUMO

Extraction behaviors of the 3 flavonoids taxifolin, diosmin, and quercetin have been investigated in Abies nephrolepis leaves and bark. The following operation parameters-ethanol volume fraction, liquid-solid ratio, temperature, ultrasound irradiation power and time, and ultrasound frequency-were varied to study their effect on the yield of the 3 flavonoids during extraction. The results showed that a low extraction efficiency occurred at 293.15 K due to slow kinetics, while the situation was significantly improved at 333.15 K. The kinetic data for the extraction yields of the 3 flavonoids achieved good fits by the first-order kinetic model. From the thermodynamic analysis results, we realized that the ultrasound-assisted extraction of taxifolin, diosmin, and quercetin from the leaves and bark of A. nephrolepis was a spontaneous and endothermic process in which the disorder increased (ΔG0 < 0, ΔH0 > 0, and ΔS0 > 0). According to the response surface methodology (RSM) analysis, under the optimal operation conditions (ethanol concentration of 50%, liquid-solid ratio of 20 mL/g, frequency of 45 kHz, extraction time of 39.25 min, ultrasound irradiation power of 160 W and temperature of 332.19 K), the total yield of the 3 flavonoids were 100.93 ± 4.01 mg/g from the leaves of A. nephrolepis (with 31.03 ± 1.51 mg/g, 0.31 ± 0.01 mg/g, 69.59 ± 2.57 mg/g for taxifolin, diosmin, and quercetin, respectively), and under the optimal operation conditions (ethanol concentration of 50%, liquid-solid ratio of 20 mL/g, frequency of 45 kHz, extraction time of 36.80 min, ultrasound irradiation power of 150 W and temperature of 328.78 K), 16.05 mg/g ± 0.38 mg/g were obtained from the bark of A. nephrolepis (with 1.44 ± 0.05 mg/g, 0.47 ± 0.01 mg/g, 14.14 ± 0.38 mg/g for taxifolin, diosmin, and quercetin, respectively), which were close to the prediction values.


Assuntos
Abies/química , Fracionamento Químico/métodos , Diosmina/isolamento & purificação , Quercetina/análogos & derivados , Quercetina/isolamento & purificação , Diosmina/química , Estrutura Molecular , Casca de Planta/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Quercetina/química , Termodinâmica , Ondas Ultrassônicas
15.
Curr Med Sci ; 40(1): 123-129, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32166674

RESUMO

Albiziae Flos (AF) has been experimentally proven to have an antidepressant effect. However, due to the complexity of botanical ingredients, the exact pharmacological mechanism of action of AF in depression has not been completely deciphered. This study used the network pharmacology method to construct a component-target-pathway network to explore the active components and potential mechanisms of action of AF. The methods included collection and screening of chemical components, prediction of depression-associated targets of the active components, gene enrichment, and network construction and analysis. Quercetin and 4 other active components were found to exert antidepressant effects mainly via monoaminergic neurotransmitters and cAMP signaling and neuroactive ligand-receptor interaction pathways. DRD2, HTR1A, and SLC6A4 were identified as important targets of the studied bioactive components of AF. This network pharmacology analysis provides guidance for further study of the antidepressant mechanism of AF.


Assuntos
Albizzia/química , Antidepressivos/farmacologia , Redes Reguladoras de Genes/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Antidepressivos/química , Humanos , Isoflavonas/química , Isoflavonas/farmacologia , Quempferóis/química , Quempferóis/farmacologia , Luteolina/química , Luteolina/farmacologia , Compostos Fitoquímicos/química , Extratos Vegetais/química , Quercetina/análogos & derivados , Quercetina/química , Quercetina/farmacologia , Receptor 5-HT1A de Serotonina/metabolismo , Receptores de Dopamina D2/metabolismo , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Transdução de Sinais/efeitos dos fármacos
16.
Z Naturforsch C J Biosci ; 75(1-2): 31-39, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-32031983

RESUMO

This study aimed to compare the biological activities of 35 herbal hydroethanolic extracts and select high potential extract, which showed antioxidative activity and inhibitory activities of α-glucosidase, lipase, and hyaluronidase, and to investigate the isolation, structural elucidation, and biological activities of five phenolic compounds from the selected extracts of Rosa gallica. On the basis of one-dimensional nuclear magnetic resonance together with the comparison with the literature values, the phenolic compounds were identified as methyl gallate (1), kaempferol-3-O-arabinofuranoside (2), multinoside A acetate (3), kaempferol (4), and quercetin (5), respectively. The results suggest that the extracts from R. gallica show the strongest biological activities in 35 herbal extracts and that 1, 4, and 5 among the five isolated compounds from rose extracts are effective in promoting antioxidative and enzymatic inhibitory activities.


Assuntos
Antioxidantes/química , Fenóis/química , Extratos Vegetais/química , Rosa/química , Antioxidantes/farmacologia , Cromatografia Líquida de Alta Pressão , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Ácido Gálico/análogos & derivados , Ácido Gálico/química , Ácido Gálico/isolamento & purificação , Quempferóis/química , Quempferóis/isolamento & purificação , Espectroscopia de Ressonância Magnética , Fenóis/isolamento & purificação , Fenóis/farmacologia , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Quercetina/química , Quercetina/isolamento & purificação
17.
Curr Pharm Biotechnol ; 21(8): 654-658, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32048963

RESUMO

The term "vitamin P" is an old but interesting concept. Most substances in this category belong to the family of flavonoids. "Vitamin P" has also been used to define the activity of some flavonoids, including quercetin, myricetin, and rutin. According to experimental studies, the "quercetin-like natural plant flavonoids" are beneficial to the body due to their various physiological and pharmacological activities in large doses (5 µM in vitro, 50 mg/kg in mice and 100 mg/kg in rats). The physiologically achievable concentration is 10 to 100 nM, which is quite high and hard to achieve from a normal diet. Thus, the physiologic activity and mechanism of "vitamin P" are still not clear. It should be noted that the quercetin-like natural plant flavonoids are physiological co-factors of cyclooxygenases (COXs), which are the rate-limiting key enzymes of prostaglandins. These quercetin-like natural plant flavonoids can strongly stimulate prostaglandin levels at lower doses (10 nM in vitro and in 0.1 mg/kg in vivo in rats). Although these "vitamin P" substances are not original substances in the body, their physiological functions affect the body. This review is focused on the most compelling evidence regarding the physiologic role and mechanism of quercetin-like natural plant flavonoids, which may be useful in understanding the physiological functions of "vitamin P", with the goal of focusing on the role of flavonoids in human physiological health.


Assuntos
Flavonoides/farmacologia , Plantas , Prostaglandina-Endoperóxido Sintases/metabolismo , Prostaglandinas/metabolismo , Quercetina/farmacologia , Rutina/farmacologia , Animais , Flavonoides/química , Humanos , Camundongos , Estrutura Molecular , Quercetina/química , Ratos , Rutina/química , Relação Estrutura-Atividade , Vitaminas
18.
Carbohydr Polym ; 234: 115927, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32070546

RESUMO

Natural active compounds with antioxidant properties and other potential health benefits, like quercetin (Qu), have aroused wide concern for developing bio-functional products. However, their applications are hindered by their intrinsic poor water solubility and chemical instability. In this paper, a natural antioxidant alpha lipoic acid (ALA) was grafted onto chitosan (CS) to synthesize a novel graft polymer (CS-graft-ALA). In particular, this graft-polymer could self-assemble into spherical nanomicelles in water, with a low critical micelle concentration (CMC) of 0.0076 mg/mL. As a robust and active nanocarrier, the CS-graft-ALA micelles showed high efficiency in encapsulating Qu and dispersing Qu in water. As found, the antioxidant activity of Qu was effectively enhanced when entrapped within CS-graft-ALA micelles. Moreover, CS-graft-ALA micelles could significantly improve the photo-stability and temperature-stability of Qu. The Qu/CS-graft-ALA micelles with excellent water dispersability, stability and improved antioxidant activity hold a great potential for wide applications.


Assuntos
Antioxidantes/farmacologia , Quitosana/farmacologia , Polímeros/farmacologia , Quercetina/farmacologia , Ácido Tióctico/farmacologia , Antioxidantes/síntese química , Antioxidantes/química , Compostos de Bifenilo/antagonistas & inibidores , Quitosana/química , Micelas , Estrutura Molecular , Tamanho da Partícula , Picratos/antagonistas & inibidores , Polímeros/síntese química , Polímeros/química , Quercetina/química , Solubilidade , Propriedades de Superfície , Ácido Tióctico/química , Água/química
19.
Molecules ; 25(3)2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-32012739

RESUMO

The aim of this study was to analyze the binding interactions between a common antihypertensive drug (ramipril, R) and the widely distributed plant flavonoid quercetin (Q), in the presence of human serum albumin (HSA). From the observed fluorescence spectra of the (HSA + R) system we can assume that ramipril is also one of the Site 3 ligands-similar to fusidic acid-the binding of which has been proven by RTG crystallography. Our claim is supported by near-UV CD spectroscopy, microscale themophoresis and molecular modeling. The presence of R slightly inhibited the subsequent binding of Q to HSA and, on the contrary, the pre-incubation of HSA with Q caused a stronger binding of R, most likely due to allosteric interactions. At high concentrations, R is also able to displace Q from its binding site. The dissociation constant KD for the binding of R is more than hundredfold larger than for Q, which means that R is a very weak binder to HSA. The knowledge of qualitative and quantitative parameters of R, as well as the methods used in this study, are important for future research into HSA binding. This study shows the importance of implementing other methods for KD determination. Microscale thermophoresis has proved to be a novel, practical and accurate method for KD determination on HSA, especially in cases when fluorescence spectroscopy is unable to produce usable results.


Assuntos
Quercetina/metabolismo , Ramipril/metabolismo , Albumina Sérica Humana/metabolismo , Sítios de Ligação , Humanos , Ligantes , Modelos Moleculares , Simulação de Acoplamento Molecular , Ligação Proteica , Conformação Proteica , Quercetina/química , Ramipril/química , Albumina Sérica Humana/química
20.
PLoS One ; 15(1): e0225514, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31929529

RESUMO

Based on ethnopharmacological studies, a lot of plants, as well as its compounds, have been investigated for the potential use as wound healing agents. In Brazil, Curatella americana is traditionally used by local people to treat wounds, ulcers and inflammations. However, to the best of our knowledge, its traditional use in the treatment of wounds has not been validated by a scientific study. Here, some compounds, many of them flavonoids, were identified in the hydroethanolic extract from the leaves of C. americana (HECA) by LC-HRMS and LC-MS/MS. Besides that, solutions containing different concentrations of HECA and a gel produced with this extract were evaluated for its antimicrobial, coagulant and wound healing activities on an excision mouse wound model as well as its acute dermal safety. A total of thirteen compounds were identified in HECA, mainly quercetin, kaempferol and glucoside derivatives of both, besides catechin and epicatechin known as wound healing agents. The group treated with 1% of HECA exhibited highest wound healing activity and best rate of wound contraction confirmed by histopathology results. The present study provides scientific evidence of, this extract (HECA) possess remarkable wound healing activity, thereby, supporting the traditional use.


Assuntos
Dilleniaceae/química , Extratos Vegetais/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Brasil , Catequina/isolamento & purificação , Cromatografia Líquida , Flavonoides/química , Flavonoides/farmacologia , Glucosídeos/química , Glucosídeos/isolamento & purificação , Humanos , Quempferóis/química , Quempferóis/isolamento & purificação , Camundongos , Extratos Vegetais/química , Folhas de Planta/química , Quercetina/química , Quercetina/isolamento & purificação , Espectrometria de Massas em Tandem
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