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1.
Zhongguo Zhong Yao Za Zhi ; 44(15): 3312-3315, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602888

RESUMO

Phytochemical investigation of the flowers of Hosta plantaginea led to isolate of one new flavonoid glycoside,plantanone C( 1) by silica gel,Sephadex LH-20,and RP-HPLC column chromatographies. Its structure was extensively determined on basis of HR-ESI-MS and NMR spectroscopic data. Compound 1 exhibited moderate antioxidant activity against DPPH radical scavenging activity,with an IC50 value of 240. 2 µmol·L~(-1).


Assuntos
Antioxidantes/isolamento & purificação , Flavonoides/isolamento & purificação , Glicosídeos/isolamento & purificação , Hosta/química , Antioxidantes/análise , Flavonoides/análise , Flores/química , Glicosídeos/análise
2.
J Enzyme Inhib Med Chem ; 34(1): 1481-1488, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31423846

RESUMO

Indoleamine 2,3-dioxygenase 1 (IDO1), a tryptophan catabolising enzyme, is known as a tumour cell survival factor that causes immune escape in several types of cancer. Flavonoids of Sophora flavescens have a variety of biological benefits for humans; however, cancer immunotherapy effect has not been fully investigated. The flavonoids (1-6) isolated from S. flavescens showed IDO1 inhibitory activities (IC50 4.3-31.4 µM). The representative flavonoids (4-6) of S. flavescens were determined to be non-competitive inhibitors of IDO1 by kinetic analyses. Their binding affinity to IDO1 was confirmed using thermal stability and surface plasmon resonance (SPR) assays. The molecular docking analysis and mutagenesis assay revealed the structural details of the interactions between the flavonoids (1-6) and IDO1. These results suggest that the flavonoids (1-6) of S. flavescens, especially kushenol E (6), as IDO1 inhibitors might be useful in the development of immunotherapeutic agents against cancers.


Assuntos
Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , Flavonoides/farmacologia , Indolamina-Pirrol 2,3,-Dioxigenase/antagonistas & inibidores , Sophora/química , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Flavonoides/química , Flavonoides/isolamento & purificação , Células HeLa , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Modelos Moleculares , Estrutura Molecular , Mutagênese Sítio-Dirigida , Relação Estrutura-Atividade , Células Tumorais Cultivadas
3.
J Agric Food Chem ; 67(36): 10222-10234, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31385700

RESUMO

The emergence and rapid spread of methicillin-resistant Staphylococcus aureus (MRSA) critically requires alternative therapeutic options. New antibacterial drugs and strategies are urgently needed to combat MRSA-associated infections. Here, we investigated the antibacterial activity of flavones from Morus alba and the potential mode of action against MRSA. Kuwanon G, kuwanon H, mulberrin, and morusin displayed high efficiency in killing diverse MRSA isolates. On the basis of structure-activity analysis, the cyclohexene-phenyl ketones and isopentenyl groups were critical to increase the membrane permeability and to dissipate the proton motive force. Meanwhile, mechanistic studies further showed that kuwanon G displayed rapid bactericidal activity in vitrowith difficulty in developing drug resistance. Kuwanon G targeted phosphatidylglycerol and cardiolipin in the cytoplasmic membrane through the formation of hydrogen bonds and electrostatic interactions. Additionally, kuwanon G promoted wound healing in a mouse model of MRSA skin infection. In summary, these results indicate that flavones are promising lead compounds to treat MRSA-associated infections through disrupting the proton motive force and membrane permeability.


Assuntos
Antibacterianos/farmacologia , Flavonas/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/metabolismo , Morus/química , Extratos Vegetais/farmacologia , Infecções Estafilocócicas/microbiologia , Animais , Antibacterianos/química , Antibacterianos/isolamento & purificação , Permeabilidade da Membrana Celular/efeitos dos fármacos , Feminino , Flavonas/química , Flavonas/isolamento & purificação , Flavonoides/química , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Humanos , Masculino , Meticilina/farmacologia , Staphylococcus aureus Resistente à Meticilina/genética , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Raízes de Plantas/química , Força Próton-Motriz/efeitos dos fármacos
4.
Chem Commun (Camb) ; 55(73): 10912-10915, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31441468

RESUMO

A novel AIE probe with ESIPT characteristics, myricetin, has been easily purified from vine tea for reversible, selective and sensitive targeting of O2˙- in turn-on mode. Its AIE nanocrystals exhibit large Stokes shift, high photostability, excellent biocompatibility, and low cytotoxicity for endogenous O2˙- detection and imaging in vitro and in vivo.


Assuntos
Flavonoides/química , Corantes Fluorescentes/química , Superóxidos/análise , Ampelopsis/química , Animais , Feminino , Flavonoides/isolamento & purificação , Flavonoides/toxicidade , Fluorescência , Corantes Fluorescentes/isolamento & purificação , Corantes Fluorescentes/toxicidade , Células HeLa , Humanos , Camundongos Endogâmicos ICR , Nanopartículas/química , Nanopartículas/toxicidade , Oxirredução , Espectrometria de Fluorescência/métodos , Superóxidos/química
5.
Plant Foods Hum Nutr ; 74(3): 399-404, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31273641

RESUMO

A simple and efficient ultrasonic-assisted extraction (UAE) technique was developed in order to find optimal conditions for the extraction of total phenolic compounds, flavonoids and anthocyanins in wild raspberry (Rubus idaeus L.) fruits. Several extraction variables, including methanol composition (v/v, %), solid-solvent ratio (g/mL), time (min) and extraction temperature (°C) were optimized using response surface methodology (RSM). Under optimal conditions for extraction, the total phenolics were found in the concentration of 383 mg GAE/100 g of fresh fruit weight, while HPLC-PDA analysis of the optimized extract showed the presence of cyanidin-3-glucoside, cyanidin-3-sophoroside, catechin, gallic and ellagic acid. The experimental values of DPPH and ABTS radical scavenging activities were 29.0 and 39.5 µmol Trolox/g of fresh fruit weight, respectively. In vitro simulated gastrointestinal digestion showed great raspberry phenolics stability. Our study assessed the bioaccessible phenolics in wild raspberry fruits and showed optimal conditions for the effective extraction of bioactive compounds for their analysis.


Assuntos
Flavonoides/análise , Frutas/química , Fenóis/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação , Rubus/química , Antocianinas/análise , Antocianinas/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Flavonoides/isolamento & purificação , Fenóis/análise , Compostos Fitoquímicos/análise , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Sonicação
6.
Food Chem ; 299: 125108, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31310914

RESUMO

Macroporous resins have been employed in the effective recovery of flavonoids from plants. In this study, S8 polar resins were used to recover flavonoids and procyanidins from lotus seedpods. Adsorption kinetics, isotherms, and thermodynamics studies revealed that the adsorption process involved physico-chemical interactions, including flavonoid-resin and flavonoid-flavonoid electrostatic interactions, π-π aromatic stacking, moderate and strong hydrogen bonding, and repulsive forces. These forces worked complementarily in adsorption, except for the repulsive force, which opposed the adsorption. Further, adsorption temperature determined the adsorption behavior, with multilayer adsorption enhancing adsorption capacity. In dynamic desorption tests, an acetone/water/acetic acid mixture (58.77: 39.34: 1.89) designed by the D-optimal design method was able to desorb 95.57% and 89.85% of total flavonoids and procyanidins, respectively, using less than two bed volumes of solvent. Ultra-performance liquid chromatography triple-time of flight/mass spectrometry (UPLC-TOF/MS) analysis showed that 26 flavonoids, including 5 procyanidins, were detected after the recovery.


Assuntos
Flavonoides/isolamento & purificação , Nelumbo/química , Resinas Sintéticas/química , Sementes/química , Adsorção , Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/análise , Flavonoides/química , Ligações de Hidrogênio , Espectrometria de Massas , Proantocianidinas/análise , Proantocianidinas/química , Proantocianidinas/isolamento & purificação , Eletricidade Estática
7.
J Agric Food Chem ; 67(32): 8819-8838, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31322880

RESUMO

Recent studies about hot-water extracts from sugar maple (Acer saccharum Marsh.) bark and buds demonstrated that they contain high amounts of phenolic structures that may be used as antioxidant food additives. However, the detailed chemical composition of these maple-derived extracts has yet to be determined. By performing high-performance liquid chromatography-diode array detector-high-resolution mass spectrometry (HPLC-DAD-HRMS)-based dereplication, we were able to spike and classify almost 100 metabolites in each hot-water extract. The sugar maple bark hot-water extract is rich in simple phenolic compounds and phenylpropanoid derivatives, while bud extract contains predominantly flavonoids, benzoic acids, and their complex derivatives (condensed and hydrolyzable tannins). Among those chemical structures, we tentatively identified 69 phenolic compounds potentially reported for the first time in the genus Acer. Considering the growing commercial demand in natural products, the phenolic fingerprints of sugar maple bark and bud hot-water extracts will help in promoting these two maple-derived products as new sources of bioactive compounds in the food, nutraceutical, and cosmetic industries.


Assuntos
Acer/química , Casca de Planta/química , Extratos Vegetais/química , Acer/metabolismo , Cromatografia Líquida de Alta Pressão , Flavonoides/química , Flavonoides/isolamento & purificação , Flavonoides/metabolismo , Fenóis/química , Fenóis/isolamento & purificação , Fenóis/metabolismo , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/metabolismo , Espectrometria de Massas por Ionização por Electrospray
8.
J Chromatogr A ; 1603: 44-50, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31272729

RESUMO

This paper proposed a double salting-out effect assisted heat-shrinkable tubing liquid phase microextraction (LPME). In the study, a low price and handy heat-shrinkable tubing was used as carrier of extraction solvent and salt film, which was placed in sample solution containing certain concentration of salt for concentrating and enriching flavonoids from human plasma. Through the double salting-out effect in different regions, this microextraction method has a good present to enhance the extraction efficiency and enrichment factors of the target analytes. Several key parameters affecting the extraction efficiency were investigated, including the type of extraction solvent, the occurring region of salting-out effect, salt concentration, pH of sample phase, stirring rate, extraction time, and volume of sample phase. Also, the mechanism of the procedure was described. Under the optimum conditions, excellent linearities with r≥ 0.9912 were obtained, the limits of detection were 2.5-150 ng/mL, the average recoveries ranged from 90.3% to 111.2%. In the new procedure, the low-cost and stable heat-shrinkable tubing was first used as carrier in LPME, combined with high performance liquid chromatography (HPLC), has been successfully applied for the determination of the trace-level target analytes in human plasma.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/sangue , Flavonoides/isolamento & purificação , Microextração em Fase Líquida/métodos , Cloreto de Sódio/química , Temperatura Alta , Humanos
9.
Fitoterapia ; 137: 104240, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31201887

RESUMO

Anhua dark tea known as the earliest produced Chinese dark tea, has been commercially available and famous for its unique flavor and health care effect. NMDA receptors are glutamate-coupled ion channels that critically involved in survival of neuronal cells and neurodegenerative diseases. Thus, it is considered a promising target for the therapy of neurodegenerative disease. In this study, four catechins including two new catechins derivatives (1-2), together with thirteen known flavonoids were isolated from Anhua dark tea. The structures of compounds 1-2 [2S,3R-6-methoxycarbonylgallocatechin (1) and 2R,3R-6-methoxycarbonylgallocatechin (2)] were determined on the basis of their spectroscopic data. The preliminary bioassay indicated that compound 1 showed the best neuroprotective effects via N-methyl-d-aspartate (NMDA) receptors inhibition. Compound 1 protected SH-SY5Y cells against NMDA-induced injury and cell apoptosis via the modulation of NR2B expression, the activation of PI3K/Akt signaling and caspase-dependent pathway. The results suggested compound 1 would be a potent dietary therapy reagent for prevention of excitable brain injury.


Assuntos
Catequina/farmacologia , Flavonoides/farmacologia , Fármacos Neuroprotetores/farmacologia , Chá/química , Apoptose , Catequina/análogos & derivados , Linhagem Celular Tumoral , Flavonoides/isolamento & purificação , Humanos , Estrutura Molecular , Neuroblastoma , Fármacos Neuroprotetores/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos
10.
Fitoterapia ; 137: 104248, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31247218

RESUMO

Hippophae rhamnoides subsp. Sinensis is a famous traditional medicinal plant in Tibet and Mongolia of China. Three novel flavonoid glycosides and ten known analogues were obtained from the seeds of H. rhamnoides. The structures of new compounds were elucidated by spectroscopics, chemical methods as well as literature data. In vitro assay, compounds 5-9, kaempferol and 70% ethanolic elution fraction showed prominent α-glucosidase inhibitory activities with IC50 values ranging from 8.30 to 112.11 µM, better than that of the positive control, acarbose, whose IC50 value was 1727.07 µM.


Assuntos
Flavonoides/farmacologia , Inibidores de Glicosídeo Hidrolases/farmacologia , Glicosídeos/farmacologia , Hippophae/química , China , Flavonoides/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Glicosídeos/isolamento & purificação , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Plantas Medicinais/química , Sementes/química , alfa-Glucosidases
11.
Food Chem ; 295: 289-299, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174761

RESUMO

A method combining solid-liquid extraction based on ethanolic aqueous solution, cLC-DAD and chemometrics, was performed to extract and quantify polyphenols from citrus peels. LC-MS/MS was also employed for chemical profiling. The effect of extraction variables on the recovery was examined by experimental factorial design. Data were evaluated using multifactorial-ANOVA, response surface analysis and Principal Component Analysis. trans-Ferulic and p-coumaric antioxidants were found in lower quantities (<1.4 mg·g-1) in all peel extracts. Narangin flavonoid was also identified in all samples, while rutin flavonol was determined in the concentration range of 3.3-4.7 mg·g-1. The most abundant polyphenol in the extracts obtained from all evaluated citrus samples was the flavanone hesperidin (280-673 mg·g-1). Furthermore, peel extracts were evaluated in terms of total polyphenol and flavonoid content, total antioxidant activity and DPPH free radical scavenging. The obtained results suggested that evaluated citrus peel by-products could be reused as a source of polyphenols and transformed into value-added products.


Assuntos
Citrus/química , Polifenóis/análise , Polifenóis/isolamento & purificação , Resíduos/análise , Análise de Variância , Antioxidantes/análise , Antioxidantes/isolamento & purificação , Cromatografia Líquida , Flavonoides/análise , Flavonoides/isolamento & purificação , Hesperidina/análise , Hesperidina/isolamento & purificação , Extratos Vegetais/análise , Extratos Vegetais/química , Análise de Componente Principal , Espectrometria de Massas em Tandem
12.
Food Chem ; 297: 124896, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253254

RESUMO

We report here the results of the study of the chemical composition of Cyperus esculentus rhizomes. Ethanolic extracts have been separated by column chromatography and analyzed by magnetic resonance spectroscopy and mass spectrometry. Quercetin, stigmasterol, and linoleic and oleic acid glycerol esters, together with 4-chlorobutyl oleate, oleamide, myricetin, tyramine and N-feruloyltyramine, found for the first time in Cyperus esculentus rhizomes, have been isolated and quantified in the extracts. Alkaloids have not been detected, and the presence of flavonoids and sterols is moderate.


Assuntos
Cyperus/química , Extratos Vegetais/química , Cromatografia Líquida de Alta Pressão , Cyperus/metabolismo , Flavonoides/análise , Flavonoides/isolamento & purificação , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Extratos Vegetais/análise , Quercetina/análise , Quercetina/isolamento & purificação , Rizoma/química , Rizoma/metabolismo
13.
J Sci Food Agric ; 99(13): 6001-6010, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31225640

RESUMO

BACKGROUND: In this study, we aimed to evaluate the influence of different extraction procedures [decoction, homogenizer-assisted extraction (HAE), infusion, maceration, Soxhlet and ultrasound-assisted extraction (UAE)] on the chemical profiling and biological properties of methanol and water extracts of Pulicaria dysenterica (L.) Bernh. The chemical profiles of the extracts were evaluated by high-performance liquid chromatography coupled to electrospray ionization and time-of-flight mass spectrometry (HPLC-ESI-TOF-MS). The antioxidant properties and enzymes (lipase, α-amylase, α-glucosidase, tyrosinase and cholinesterases) inhibitory potential of the extracts were evaluated. RESULTS: The chemical profiles were dependent on the type of extraction methods as well as on the type of solvent. The methanolic extracts showed higher levels of total phenolic, flavonoid, and phenolic acid content, while the highest total flavonol content was observed in the HAE-water extract. Forty different compounds were identified from P. dysenterica. In relation to the potential in vitro anti-diabetic effects, the highest activity against the studied key enzymes was observed for the macerated extract (α-amylase: 0.58 ± 0.03 and α- glucosidase: 1.65 ± 0.03 mmol ACAE g-1 ). The HAE-methanol extract was the most potent inhibitor of cholisterases, whereas the highest activities against tyrosinase were observed for UAE-methanol extract, followed by macerated and Soxhlet. The inhibitory activity of the studied extracts against lipase were in the order: soxhlet > macerated> HAE-methanol > UAE-methanol. CONCLUSION: This study has established scientific baseline data on the therapeutic properties of P. dysentrica, thereby advocating the need for further investigations in an endeavour to develop novel pharmaceuticals from this plant. © 2019 Society of Chemical Industry.


Assuntos
Extratos Vegetais/química , Pulicaria/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Flavonoides/química , Flavonoides/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/química , Análise Multivariada , Fenóis/química , Fenóis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Espectrometria de Massas por Ionização por Electrospray , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/química , alfa-Glucosidases/química
14.
J Food Sci ; 84(7): 1943-1948, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31211417

RESUMO

Melons are a diverse group of fresh, dessert fruits that includes orange flesh cantaloupe, green flesh honeydew, and mixed hybrid melons. As part of an effort to discover potential health benefits of fruit and vegetable peels that are considered to be byproducts of food processing, we determined the total phenolic content and antioxidative activities of methanolic extracts of the powdered peels of the following commercial melon (Cucumis melo) varieties sold at retail markets in California that were imported from Mexico and Honduras: nonorganic Canary, Charentias, Hani Gold, Vine ripened, and Santa Claus; and organic Ambrosia, Cantaloupe, Galia, Goddess, Ham, Honeydew, and Tuscan. The total phenolic content (in mg gallic acid equivalents/g extract) ranged from 0.69 (Tuscan) to 2.96 (Galia) or 4.3-fold variation from lowest to highest value. The antioxidative activity (in mg ascorbic acid equivalents/mL extract) ranged from 0.13 (organic Tuscan) to 0.26 (organic Galia). Similar results were observed using the ABTS antioxidative assay. The content of the phenolic and flavonoid compounds 3-hydroxybenzoic acid, chlorogenic acid, neochlorogenic acid, isovanillic acid, apigenin-7-α-glucoside, luteolin-7-o-glucoside, and quercetin-3-galactoside in three melon flesh samples (nonorganic and organic Galia from Honduras and organic Galia from Mexico and two peel samples (Mexican organic peel and flesh) were analyzed using HPLC. The results suggest that the peel from the Honduran Galia melon with the highest antioxidative activity merits further study to investigate potential health properties. Potential nutritional and health benefits of melon peels, Seeds, and their bioactive compounds are discussed. PRACTICAL APPLICATION: The peel from the Honduran Galia melon variety merits further study for potential health benefits, including antioxidative, anticholesterol, and antidiabetic activities, and stimulation of thyroid function, as reported for peels from other melon varieties, as well as antibiotic activities against pathogenic bacteria, protozoa, and viruses.


Assuntos
Antioxidantes/química , Cucumis melo/química , Fenóis/química , Extratos Vegetais/química , Antioxidantes/análise , California , Cromatografia Líquida de Alta Pressão , Flavonoides/química , Flavonoides/isolamento & purificação , Manipulação de Alimentos , Frutas/química , México , Fenóis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Pós/química , Pós/isolamento & purificação , Sementes/química
15.
Food Chem ; 293: 438-445, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31151632

RESUMO

In this study, deep eutectic solvents (DESs) coupled with ultrasound-assisted extraction (UAE) were evaluated and optimized for the extraction of major flavonoids from common buckwheat sprouts. Initially, 18 different choline chloride (CC)-based DESs were evaluated as potential extraction solvents, and 80% CCTG (CC-based DES composed of triethylene glycol and 20 vol% water) extracted significantly higher (p < 0.05) amounts of flavonoids than other DESs studied. The extraction efficiency of 80% CCTG was even higher (p < 0.05) than that of methanol for the extraction of vitexin and quercetin-3-O-robinobioside. Procedure using 80% CCTG and UAE were optimized; an extraction temperature of 56 °C and extraction time of 40 min were considered optimal. The optimized extraction procedure was reliable and efficient for the extraction of major flavonoids from common buckwheat sprouts. In addition, flavonoids could be efficiently recovered from DES extracts with high recovery yields (>97%) by using a C18 solid-phase extraction.


Assuntos
Fagopyrum/química , Flavonoides/química , Extratos Vegetais/química , Solventes/química , Cromatografia Líquida de Alta Pressão , Fagopyrum/metabolismo , Flavonoides/isolamento & purificação , Extração em Fase Sólida , Sonicação , Temperatura Ambiente
16.
Eur J Med Chem ; 178: 108-115, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31176093

RESUMO

As dual regulators, the PTP-1B signaling pathway and α-glucosidase slow glucose release and increase the degree of insulin sensitivity, representing a promising therapeutic target for type 2 diabetes. In this study, we systematically examined the in vivo and in vitro anti-diabetic activities of natural flavonoids 1-6 from Chrysanthemum morifolium. Flavonoids 1-6 increased glucose consumption-promoting activity and the phosphorylation of GSK-3ß and Akt, and decreased PTP-1B protein level along with slightly inhibitory activity of the PTP-1B enzyme. Moreover, flavonoids 1-2 treatment induced insulin secretion in INS-1 cells. Besides, in vivo study revealed that flavonoids 2 and 5 demonstrated potent anti-hyperglycemic and anti-hyperlipidemic activity, and improved maltose and glucose tolerance. Although flavonoid 2 exhibited lower inhibitory activity against α-glucosidase in vitro, it could deglycosylated in vivo to diosmetin to function as an α-glucosidase inhibitor. Taken together, these results led to the identification of the natural flavonoids 1-6 from C. morifolium as dual regulators of α-glucosidase and the PTP-1B signaling pathway, suggesting their potential application as new oral anti-diabetic drugs or functional food ingredients.


Assuntos
Chrysanthemum/química , Diabetes Mellitus Experimental/tratamento farmacológico , Flavonoides/uso terapêutico , Inibidores de Glicosídeo Hidrolases/uso terapêutico , Hipoglicemiantes/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Colesterol/sangue , Cricetulus , Diabetes Mellitus Experimental/induzido quimicamente , Flavonoides/isolamento & purificação , Glucose/metabolismo , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Hipoglicemiantes/isolamento & purificação , Masculino , Camundongos , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Ratos , Estreptozocina , Triglicerídeos/sangue
17.
BMC Complement Altern Med ; 19(1): 148, 2019 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-31238930

RESUMO

BACKGROUND: Sea buckthorn (Elaeagnus rhamnoides (L.) A. Nelson, SBT) is a valuable plant because of its medical and therapeutic potential. Different bioactive compounds in SBT berries are of special interest to various researchers. However, not only sea buckthorn berries, but also leaves of this plant (both fresh and dried) contain a lot of nutrients and bioactive compounds, including phenolic compounds. The present study was carried out in order to investigate antioxidant and anticoagulant properties of sea buckthorn twig and leaf extracts (0.5-50 µg/mL) by using various in vitro models. Moreover, the aim of present experiments was to compare the biological activity of SBT leaf extract and SBT twig extract with selected berry extracts (a rich source of phenolic compounds): SBT berry extract (flavonoids being the dominant components), a commercial extract from the berries of Aronia melanocarpa (Aronox®), and a grape seed extract. METHODS: We determined the effect of plant extracts on the oxidative stress using selected markers of this process, i.e. the level of carbonyl groups in proteins. Additionally, we analysed the potential mechanism of modulation of hemostatic properties of human plasma (using selected coagulation times). RESULTS: SBT twig and leaf extracts were observed to exhibit an antioxidant activity against two strong biological oxidants: hydrogen peroxide (H2O2) and H2O2/Fe (the donor of hydroxyl radicals), which induced human plasma lipid peroxidation and protein carbonylation. Both extracts also showed anticoagulant properties. CONCLUSIONS: Our present results have demonstrated that extracts from different parts of SBT, especially berries and twigs, in comparison to well-known berries (aronia and grape), may also be viewed as a good source of active substances - antioxidants for pharmacological or cosmetic applications. Moreover, it is very important from an economic point of view to know that there is a possibility of obtaining phenolic compounds not only from the berries or leaves, but also from twigs, which constitute a production waste.


Assuntos
Elaeagnaceae/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Caules de Planta/química , Anticoagulantes/química , Anticoagulantes/isolamento & purificação , Anticoagulantes/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Flavonoides/química , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Frutas/química , Humanos , Fenóis/química , Fenóis/isolamento & purificação , Fenóis/farmacologia , Photinia/química , Extratos Vegetais/isolamento & purificação , Tempo de Protrombina
18.
Biotechnol Appl Biochem ; 66(4): 698-708, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31172593

RESUMO

Phytosynthesis of gold nanoparticles (AuNPs) has achieved an indispensable significance due to the diverse roles played by biomolecules in directing the physiochemical characteristics of biosynthesized nanoparticles. Therefore, the precise identification of key bioactive compounds involved in producing AuNPs is vital to control their tunable characteristics for potential applications. Herein, qualitative and quantitative determination of key biocompounds contributing to the formation of AuNPs using aqueous Elaeis guineensis leaves extract is reported. Moreover, roles of phenolic compounds and flavonoids in reduction of Au3+ and stabilization of AuNPs have been elucidated by establishing a reaction mechanism. Fourier-transform infrared spectroscopy (FTIR) showed shifting of O─H stretching vibrations toward longer wavenumbers and C═O toward shorter wavenumbers due to involvement of polyphenolic compounds in biosynthesis and oxidation of polyphenolic into carboxylic compounds, respectively, which cape nanoparticles to inhibit the aggregation. Congruently, pyrolysis-gas chromatography-mass spectrometry revealed the major contribution of polyphenolic compounds in the synthesis of AuNPs, which was further endorsed by reduction of total phenolic and total flavonoids contents from 48.08 ± 1.98 to 9.59 ± 0.92 mg GAE/g and 32.02 ± 1.31 to 13.8 ± 0.97 mg CE/g within 60 Min, respectively. Based on experimental results, reaction mechanism explained the roles of phenolic compounds and flavonoids in producing spherical-shaped AuNPs.


Assuntos
Flavonoides/química , Ouro/metabolismo , Química Verde , Nanopartículas Metálicas/química , Fenóis/química , Extratos Vegetais/química , Folhas de Planta/química , Arecaceae/química , Flavonoides/isolamento & purificação , Ouro/química , Estrutura Molecular , Tamanho da Partícula , Fenóis/isolamento & purificação , Processos Fotoquímicos , Extratos Vegetais/isolamento & purificação , Estresse Mecânico , Propriedades de Superfície , Água/química , Água/metabolismo
19.
Food Chem ; 297: 124970, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253303

RESUMO

Choline chloride-based deep eutectic solvents (DESs) were used as green alternatives to conventional organic solvents for extracting valuable flavonoids from citrus peel waste. The effects of viscosity, pH, and polarity of DESs on the extraction efficiency were investigated. Results revealed linear dependence of extraction yield of citrus flavonoids on the polarity of the hydrogen bond donor (HBD). To simultaneously and effectively extract polymethoxylated flavonoids (PMFs) and glycosides of flavonoids (GoFs) with different polarities, five ternary DESs were designed and prepared by combining the effective HBD components. Among the tailor-made DESs studied, choline chloride-levulinic acid-N-methyl urea showed the highest extraction yield of total flavonoids. Under optimized extraction conditions, 18.75 mg/g PMFs and 47.07 mg/g GoFs were extracted from citrus peel with recoveries of 95.87% and 86.32%, respectively. This study presents a useful strategy based on tailor-made DESs to selectively extracted value-added flavonoids from waste peels in the citrus-processing industry.


Assuntos
Fracionamento Químico/métodos , Citrus/química , Flavonoides/isolamento & purificação , Solventes/química , Colina/química , Flavonoides/química , Glicosídeos/química , Glicosídeos/isolamento & purificação , Ligações de Hidrogênio , Concentração de Íons de Hidrogênio , Temperatura Ambiente , Viscosidade , Resíduos
20.
J Food Sci ; 84(6): 1308-1314, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31042818

RESUMO

Water was bubbled with gases including nitrogen (N2 ), oxygen (O2 ), hydrogen (H2 ), carbon dioxide (CO2 ), and air for 10 min and phenolics from green tea leaves were extracted using the prepared gas-bubbled water. To retain the gases in water, the extraction conditions were maintained in an air-tight container at room temperature under magnetic stirring. Radical scavenging ability, total phenolic content, and phenolic profiles of the extracts were analyzed, and gas-bubbled water was examined to explain the differences in phenolic contents. Overall, green tea infusion prepared from H2 -bubbled water contained significantly high levels of total phenolic compounds and antioxidant activity compared to other gas-bubbled waters including N2 , O2 , CO2 , and air (P < 0.05).Control samples and those bubbled with CO2 showed the lowest antioxidant activities in green tea infusion. However, green tea extracts with O2 bubbling showed the lowest catechin content. Green tea leaves treated with hydrogen gas-bubbled water had much greater damage to their surface morphological properties compared to the other groups, which may explain the higher yield of phenolic compounds. Overall, hydrogen gas-bubbled water showed better extraction yield of phenolics from green tea leaves than other gas-bubbled water. PRACTICAL APPLICATION: Green tea or green tea infusion has diverse health beneficial functionality due to the presence of phenolic compounds. In this study, different gases including nitrogen, oxygen, hydrogen, and carbon dioxide were treated in water and these gas-bubbled water were used to extract phenolics from green tea leaves. Among them, hydrogen-bubbled water extracted the highest phenolic contents from tea leaves and showed the highest in vitro antioxidant ability in green tea infusion compared to other gas-bubbled water. This new knowledge could help to produce green teas with higher antioxidant activity in beverage industry.


Assuntos
Camellia sinensis/química , Manipulação de Alimentos/métodos , Fenóis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Antioxidantes/análise , Antioxidantes/isolamento & purificação , Catequina/análise , Catequina/isolamento & purificação , Flavonoides/análise , Flavonoides/isolamento & purificação , Gases/química , Fenóis/análise , Extratos Vegetais/análise , Folhas de Planta/química , Água/química
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