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1.
J Agric Food Chem ; 67(42): 11684-11693, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31564105

RESUMO

Enzymatic acylation is commonly used to increase the lipophilicity of flavonoids. However, the absence of primary hydroxyl groups makes it challenging to acylate baicalin using traditional acylation methods. In this study, an enzymatic esterification strategy was developed to introduce fatty-acid chains into baicalin at its carboxyl group, hence successfully synthesizing a new series of baicalin ester derivatives in nonaqueous media. Under the optimal reaction conditions, up to 95% conversion of baicalin was achieved. Antimicrobial evaluation of the baicalin ester derivatives indicated a corresponding increase to that of C log P values, with a cutoff effect at C log P = 5.2. Baicalin ester derivatives with C log P values of 4.9-5.2 exhibited the most potent antimicrobial activity. Interestingly, the introduction of medium-length fatty alcohol chains not only increased lipophilicity but also endowed them with membrane-disrupting properties. This study, therefore, provides an understanding of the esterification of flavonoid glycosides and a prospective application of the ester derivatives.


Assuntos
Anti-Infecciosos/química , Flavonoides/química , Lipase/química , Acilação , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Biocatálise , Esterificação , Ácidos Graxos/química , Flavonoides/farmacologia , Leveduras/efeitos dos fármacos
2.
J Agric Food Chem ; 67(40): 11053-11065, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31525973

RESUMO

Oilseed rape (Brassica napus L.) is the second highest yielding oil crop worldwide. In addition to being used as an edible oil and a feed for livestock, rapeseed has high ornamental value. In this study, we identified and characterized the main floral major constituents, including phenolic acids and flavonoids components, in rapeseed accessions with different-colored petals. A total of 144 constituents were identified using ultrahigh-performance liquid chromatography-HESI-mass spectrometry (UPLC-HESI-MS/MS), 57 of which were confirmed and quantified using known standards and mainly contained phenolic acids, flavonoids, and glucosinolates compounds. Most of the epicatechin, quercetin, and isorhamnetin derivates were found in red and pink petals of B. napus, while kaempferol derivates were in yellow and pale white petals. Moreover, petal-specific compounds, including a putative hydroxycinnamic acid derivative, sinapoyl malate, 1-O-sinapoyl-ß-d-glucose, feruloyl glucose, naringenin-7-O-glucoside, cyanidin-3-glucoside, cyanidin-3,5-di-O-glucoside, petunidin-3-O-ß-glucopyranoside, isorhamnetin-3-O-glucoside, kaempferol-3-O-glucoside-7-O-glucoside, quercetin-3,4'-O-di-ß-glucopyranoside, quercetin-3-O-glucoside, and delphinidin-3-O-glucoside, might contribute to a variety of petal colors in B. napus. In addition, bound phenolics were tentatively identified and contained three abundant compounds (p-coumaric acid, ferulic acid, and 8-O-4'-diferulic acid). These results provide insight into the molecular mechanisms underlying petal color and suggest strategies for breeding rapeseed with a specific petal color in the future.


Assuntos
Brassica napus/química , Flores/química , Extratos Vegetais/química , Cromatografia Líquida de Alta Pressão/métodos , Cor , Ácidos Cumáricos/química , Flavonoides/química , Hidroxibenzoatos/química , Quempferóis/química , Espectrometria de Massas em Tandem/métodos
3.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 33(9): 1181-1189, 2019 Sep 15.
Artigo em Chinês | MEDLINE | ID: mdl-31512463

RESUMO

Objective: To investigate the effect of icarin/attapulgite/collagen type Ⅰ/polycaprolactone (ICA/ATP/Col Ⅰ/PCL) composite scaffold in repair of rabbit tibia defect. Methods: The ICA/20%ATP/Col Ⅰ/PCL (scaffold 1), ICA/30%ATP/Col Ⅰ/PCL (scaffold 2), 20%ATP/Col Ⅰ/PCL (scaffold 3), and 30%ATP/Col Ⅰ/PCL (scaffold 4) composite scaffolds were constructed by solution casting-particle filtration method. The structure characteristics of the scaffold 2 before and after cross-linking were observed by scanning electron microscopy, and the surface contact angles of the scaffold 2 and the scaffold 4 were used to evaluate the water absorption performance of the material. The in vitro degradation test was used to evaluate the sustained-release effect of the scaffold 2. Thirty male Japanese white rabbits, weighing (2.0±0.1) kg, were randomly divided into groups A, B, C, D, and E, 6 in each group. After making a 1 cm- diameter bilateral tibial defects model, group A was the defect control group without any material implanted. Groups B, C, D, and E were implanted with scaffolds 3, 4, 1, and 2 at the defect sites, respectively. At 4, 8, and 12 weeks after operation, the repairing effects of 4 scaffolds were observed by gross observation, histological observation of HE and Masson staining, and immunohistochemical staining of osteogenic specific transcription factor (runt-related transcription factor 2, RUNX2), osteogenic related transcription factor [Osterix (OSX), Col Ⅰ, osteopontin (OPN)]. Results: Scanning electron microscopy observation showed that the scaffolds were all porous. The structure of the material was loose before and after cross-linking. The surface contact angle showed that the scaffold was hydrophobic, and the scaffold 2 was more hydrophobic than scaffold 4. The sustained-release effect in vitro showed that the drug could be released in a micro and long-term manner. In the animal implantation experiment, the gross observation showed that the defects were significantly smaller in groups D and E than in groups A, B, and C at 4 and 12 weeks after operation. HE and Masson staining showed that the defect of group A was full of connective tissue at 4 weeks after operation, a large number of fibers were seen in groups B and C, and the new bone formation was observed in groups D and E. The increase of new bone was observed in each group at 8 weeks after operation. The defect of group A was still dominated by connective tissue at 12 weeks after operation, and a small amount of new bone tissue was observed in groups B and C, and a large number of new bone tissue was observed in groups D and E, especially in group E, and most of the materials degraded. Immunohistochemical staining showed that the expressions of RUNX2 and OSX in the new tissues of groups D and E were significantly higher than those of the other groups at 4 weeks after operation. The expression of RUNX2 decreased at 8 and 12 weeks after operation. After 8 weeks and 12 weeks, the expressions of Col Ⅰand OPN increased than in 4 weeks. And the expressions of Col Ⅰ and OPN in the new tissues of groups D and E were significantly more than those of the other groups. Conclusion: ICA/ATP/Col I/PCL composite scaffolds have good porosity and biocompatibility, can promote bone formation, and have good bone regeneration and repair effect.


Assuntos
Colágeno Tipo I , Engenharia Tecidual , Tecidos Suporte , Animais , Flavonoides/química , Compostos de Magnésio/química , Masculino , Poliésteres/química , Coelhos , Distribuição Aleatória , Compostos de Silício/química , Tíbia/lesões , Engenharia Tecidual/métodos , Engenharia Tecidual/normas , Tecidos Suporte/química , Tecidos Suporte/normas
4.
Bol. latinoam. Caribe plantas med. aromát ; 18(5): 444-458, sept. 2019. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1008263

RESUMO

This review work focuses on how the secondary chemistry could help in the survival of plants in high mountain habitats under extreme environmental conditions. The elevated levels of stress in high areas of the tropic and subtropic change dramatically not only by following the annual cycles of winter and summer but they also change in a single day. Some species, however, are able to successfully grow at heights more than 3000 m in the tropical mountains due, in part, to highly specialized physiological processes that affect their physical and chemical responses. In this study, it describes some strategies of how the secondary metabolites could help the plants to stand the high levels of stress in the high mountain ecosystems.


Este trabajo de revisión se centra en cómo la química secundaria podría ayudar en la supervivencia de plantas en hábitats de alta montaña en condiciones ambientales extremas. Los altos niveles de estrés en las zonas altas del trópico y subtrópico cambian dramáticamente no solo al seguir los ciclos anuales de invierno y verano, sino que también cambian en un solo día. Sin embargo, algunas especies pueden crecer con éxito a alturas superiores a 3000 m en las montañas tropicales debido, en parte, a procesos fisiológicos altamente especializados que afectan sus respuestas físicas y químicas. En esta revisión, se describen algunas estrategias de cómo los metabolitos secundarios podrían ayudan a las plantas a soportar los altos niveles de estrés en los ecosistemas de alta montaña.


Assuntos
Plantas/química , Estresse Fisiológico , Óleos Voláteis/química , Altitude , Floroglucinol/análise , Floroglucinol/química , Terpenos/análise , Terpenos/química , Flavonoides/análise , Flavonoides/química
5.
J Agric Food Chem ; 67(35): 9967-9978, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31403784

RESUMO

Following the recent completion of the draft genome sequence of the tea plant, high-throughput decoding of gene function, especially for those involved in complex secondary metabolic pathways, has become a major challenge. Here, we profiled the metabolome and transcriptome of 11 tea cultivars, and then illustrated a weighted gene coexpression network analysis (WGCNA)-based system biological strategy to interpret metabolomic flux, predict gene functions, and mine key regulators involved in the flavonoid biosynthesis pathway. We constructed a multilayered regulatory network, which integrated the gene coexpression relationship with the microRNA target and promoter cis-regulatory element information. This allowed us to reveal new uncharacterized TFs (e.g., MADSs, WRKYs, and SBPs) and microRNAs (including 17 conserved and 15 novel microRNAs) that are potentially implicated in different steps of the catechin biosynthesis. Furthermore, we applied metabolic-signature-based association method to capture additional key regulators involved in catechin pathway. This provides important clues for the functional characterization of five SCPL1A acyltransferase family members, which might be implicated in the production balance of anthocyanins, galloylated catechins, and proanthocyanins. Application of an "omics"-based system biology strategy should facilitate germplasm utilization and provide valuable resources for tea quality improvement.


Assuntos
Camellia sinensis/metabolismo , Flavonoides/química , Redes Reguladoras de Genes , Camellia sinensis/química , Camellia sinensis/classificação , Camellia sinensis/genética , Flavonoides/metabolismo , Regulação da Expressão Gênica de Plantas , Metabolômica , Folhas de Planta/química , Folhas de Planta/classificação , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transcriptoma
6.
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
7.
Anticancer Res ; 39(8): 4043-4053, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31366486

RESUMO

BACKGROUND/AIM: Triple-negative breast cancer (TNBC) is the most aggressive subtype, predominant in African American women. In this study, the antioxidant/anticancer activity of muscadine grape extracts and the role of their phenolic and flavonoid contents in exerting these properties were investigated in TNBC cells. MATERIALS AND METHODS: Berry extracts from muscadine genotypes were investigated for total phenolic content (TPC), total flavonoid content (TFC), antioxidant capacity, and anticancer effects using breast cancer cell lines, representing Caucasians and African Americans. RESULTS: The antioxidant activity was associated with high TPC content. Extracts showed cytotoxicity up to 78.6% in Caucasians and 90.7% in African American cells, with an association with high antioxidant capacity. There was a strong correlation between TPC and anticancer/antioxidant activities. CONCLUSION: The anticancer and antioxidant effects of muscadine grapes are attributed to the TPC of extracts, which showed a stronger positive correlation with growth inhibition of African American breast cancer cells compared to Caucasians.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Extratos Vegetais/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Vitis/química , Afro-Americanos/genética , Antineoplásicos Fitogênicos/química , Antioxidantes/química , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Feminino , Flavonoides/química , Flavonoides/farmacologia , Frutas/química , Humanos , Células MCF-7 , Fenóis/química , Fenóis/farmacologia , Extratos Vegetais/química , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia
8.
J Agric Food Chem ; 67(37): 10521-10533, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31461284

RESUMO

This work was designed to comparatively investigate 27 dietary flavonoids that act as α-glucosidase inhibitors and insulin sensitizers. On the basis of the results of an in vitro experiment of α-glucosidase inhibition, myricetin (IC50 = 11.63 ± 0.36 µM) possessed the strongest inhibitory effect, followed by apigenin-7-O-glucoside (IC50 = 22.80 ± 0.24 µM) and fisetin (IC50 = 46.39 ± 0.34 µM). A three-dimensional quantitative structure-activity relationship model of α-glucosidase inhibitors with good predictive capability [comparative molecular field analysis, q2 = 0.529, optimum number of components (ONC) = 10, R2 = 0.996, F = 250.843, standard error of estimation (SEE) = 0.064, and two descriptors; comparative similarity index analysis, q2 = 0.515, ONC = 10, R2 = 0.997, F = 348.301, SEE = 0.054, and four descriptors] was established and indicated that meta positions of ring B favored bulky and minor, electron-withdrawing, and hydrogen bond donor groups. The presence of electron-donating and hydrogen bond acceptor groups at position 4' of ring B could improve α-glucosidase activity. Position 3 of ring C favored minor, electron-donating, and hydrogen bond donor groups, whereas position 7 of ring A favored bulky and hydrogen bond acceptor groups. Molecular docking screened five flavonoids (baicalein, isorhamnetin-3-O-rutinoside, apigenin-7-O-glucoside, kaempferol-7-O-ß-glucoside, and cyanidin-3-O-glucoside) that can act as insulin sensitizers and form strong combinations with four key protein targets involved in the insulin signaling pathway. Apigenin-7-O-glucoside (60 µM) can effectively improve insulin resistance, and glucose uptake increased by approximately 73.06% relative to the model group of insulin-resistant HepG2 cells. Therefore, apigenin-7-O-glucoside might serve as the most effective α-glucosidase inhibitor and insulin sensitizer. This work may guide diabetes patients to improve their condition through dietary therapy.


Assuntos
Flavonoides/química , Inibidores de Glicosídeo Hidrolases/química , Insulina/metabolismo , Flavonoides/metabolismo , Flavonoides/farmacologia , Inibidores de Glicosídeo Hidrolases/metabolismo , Inibidores de Glicosídeo Hidrolases/farmacologia , Células Hep G2 , Humanos , Simulação de Acoplamento Molecular , Saccharomyces cerevisiae/enzimologia , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , alfa-Glucosidases/química , alfa-Glucosidases/metabolismo
9.
J Agric Food Chem ; 67(38): 10726-10733, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31469953

RESUMO

A turn-on fluorescent probe, HOCD-RB, for monitoring singlet oxygen (1O2) was developed by linking rhodamine B as fluorophore with dimethylhomoocoerdianthrone (HOCD) as 1O2 reaction site and fluorescence quencher due to the intramolecular energy transfer (ET) between rhodamine B and HOCD moieties. Upon exposure to 1O2 it rapidly forms endoperoxide with HOCD and turns on the fluorescence of rhodamine B by 18-fold. Taking advantage of the HOCD-RB probe that shows fast response, high sensitivity, and selectivity for 1O2, it is applied for imaging of endogenous 1O2 in living cells and the fluorometric assay for evaluating 1O2 quenching activity of selected common flavonoids found in our daily diets. The results show that the 1O2 scavenging activity of flavonoids depends on not only the structure of individual flavonoid but also the competitive interactions between mixed flavonoids. The best antioxidant capacity for individual and mixed flavonoids is epigallocatechin gallate and the mixture of catechin gallate with kaempferol, respectively. Overall, this work provided a new tool for detection and imaging of singlet oxygen activity in a biological system as well as an efficient fluorometric assay of 1O2 scavenging activity.


Assuntos
Flavonoides/química , Corantes Fluorescentes/química , Fluorometria/métodos , Depuradores de Radicais Livres/química , Rodaminas/química , Oxigênio Singlete/química , Fluorescência , Estrutura Molecular
10.
Gene ; 717: 144046, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31434006

RESUMO

Flavonoids are major polyphenol compounds in plant secondary metabolism. The hydroxylation pattern of the B-ring of flavonoids is determined by the flavonoid 3'-hydroxylase (F3'H) and flavonoid 3',5'-hydroxylase (F3'5'H). In this paper, one CsF3'H and two CsF3'5'Hs (CsF3'5'Ha and CsF3'5'Hb) were isolated. The phylogenetic tree results showed that F3'H and F3'5'Hs belong to the CYP75B and CYP75A, respectively. The Expression pattern analysis showed that the expression of CsF3'5'Ha and CsF3'5'Hb in the bud and 1st leaf were higher than other tissues. However, the CsF3'H had the highest expression in the 4th and mature leaf. The correlation analysis showed that the expression of CsF3'5'Hs is positively associated with the concentration of B-trihydroxylated catechins, and the expression of CsF3'H is positively associated with the Q contentration. Heterologous expression of these genes in yeast showed that CsF3'H and CsF3'5'Ha can catalyze flavanones, flavonols and flavanonols to the corresponding 3', 4' or 3', 4', 5'-hydroxylated compounds, for which the optimum substrate is naringenin. The enzyme of CsF3'5'Hb can only catalyze flavonols (including K and Q) and flavanonols (DHK and DHQ), of which the highest activities in catalyzing are DHK. Interestingly, The experiment of site-directed mutagenesis suggested that two novel sites near the C-terminal were discovered impacting on the activity of the CsF3'5'H. These results provide a significantly molecular basis on the accumulation B-ring hydroxylation of flavonoids in tea plant.


Assuntos
Camellia sinensis/genética , Sistema Enzimático do Citocromo P-450/genética , Flavonoides/metabolismo , Camellia sinensis/metabolismo , Clonagem Molecular , Sistema Enzimático do Citocromo P-450/metabolismo , Flavonoides/química , Regulação da Expressão Gênica de Plantas , Hidroxilação , Mutagênese Sítio-Dirigida , Filogenia , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Saccharomyces cerevisiae/genética
11.
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
12.
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
13.
Phytochemistry ; 166: 112075, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31351332

RESUMO

Isoflavonoids are one of the most important groups of naturally occurring antioxidants. Their structural features are important for evaluating their antioxidative activity. In this work, density functional theory (DFT) methods were applied to investigate the influence of the C2=C3 double bond on the antioxidative activity of isoflavonoids based on three currently accepted radical scavenging mechanisms from the viewpoint of thermodynamics. The C2=C3 double bond can make the compounds more flat, which would extend the conjugated system in the molecule and make the isoflavonoids higher antioxidant activity. The C2=C3 double bond would not alter the strongest antioxidative hydroxyl group of the isoflavonoids. In the gas, benzene and CHCl3 phases, the C2=C3 double bond will enhance the antioxidative activity of isoflavonoids by lowering the bond dissociation enthalpies of the hydroxyl groups in the B ring that are the strongest antioxidative sites for the hydrogen atom transfer (HAT) mechanism. In polar phases, a similar result is obtained by weakening the proton affinity of 7-OH that is the strongest antioxidative hydroxyl group in the sequential proton loss electron transfer (SPLET), mechanism. Thus, the C2=C3 double bond will enhance the antioxidative activity of isoflavonoids irrespective of the studied phases.


Assuntos
Antioxidantes/química , Carbono/química , Teoria da Densidade Funcional , Flavonoides/química , Solventes/química , Termodinâmica
14.
Food Chem ; 298: 125098, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31276942

RESUMO

This work aimed to optimize an aqueous extract rich in phenolic compounds and potential functional properties made of Ilex paraguariensis, Melissa officinalis, and Cymbopogon citratus. The lyophilized extract was used for the development of an ice cream. Total phenolics, FRAP, DPPH, Folin-Ciocalteu's reducing capacity, and total reducing capacity of different combinations of herbal extracts were tested and modeled using response surface methodology. Simultaneous optimisation was employed to maximize the bioactive compounds in the extract and the lyophilized optimum combination was added to ice cream. The lyophilized extract contained quercetin-3-rutinoside, hesperidin, isoquercetin, caffeic acid, and 5,7-dihydroxyflavone. The optimised extract, which showed antihypertensive, antidiabetic, and antioxidant activity using in vitro protocols, increased total phenolics and antioxidant activity in comparison to the control ice cream. The ice cream presented a sensory acceptance index of 83%. After 72 days of storage (-18 °C), total phenolics and antioxidant activity significantly decreased.


Assuntos
Indústria de Processamento de Alimentos/métodos , Sorvetes , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Adolescente , Adulto , Anti-Infecciosos/farmacologia , Anti-Hipertensivos/química , Anti-Hipertensivos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Linhagem Celular , Cymbopogon/química , Feminino , Flavonoides/análise , Flavonoides/química , Armazenamento de Alimentos , Humanos , Sorvetes/análise , Ilex paraguariensis/química , Masculino , Melissa/química , Pessoa de Meia-Idade , Oligossacarídeos/química , Fenóis/química , Paladar
15.
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
16.
Analyst ; 144(17): 5232-5244, 2019 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-31360935

RESUMO

Leishmaniasis comprises a group of infectious diseases with worldwide distribution, of which both the visceral and cutaneous forms are caused by Leishmania parasites. In the absence of vaccines, efficacious chemotherapy remains the basis for leishmaniasis control. The available drugs are expensive and associated with several secondary adverse effects. Due to these limitations, the development of new antileishmanial compounds is imperative, and plants offer various perspectives in this regard. The present study evaluated the in vitro leishmanicidal activity of flavonoids isolated from Solanum paludosum Moric. and investigated the mechanisms of cell death induced by them. These compounds were evaluated in vitro for their antileishmanial activity against Leishmania amazonensis promastigotes and they showed prominent leishmanicidal activity. The EtOAc fraction, gossypetin 3,7,8,4'-tetra-O-methyl ether (1), and kaempferol 3,7-di-O-methyl ether (3) were selected to be used in an in vitro assay against L. amazonensis amastigotes and cell death assays. The flavonoids (1) and (3) presented significant activity against L. amazonensis amastigotes, exhibiting the IC50 values of 23.3 ± 4.5 µM, 34.0 ± 9.6 µM, and 10.5 ± 2.5 µM for the EtOAc fraction, (1), and (3), respectively, without toxic effects to the host cells. Moreover, (1) and (3) induced blocked cell cycle progression at the G1/S transition, ultimately leading to G1/G0 arrest. Flavonoid (3) also induced autophagy. Using Raman spectroscopy in conjunction with principal component analysis, the biochemical changes in the cellular components induced by flavonoids (1) and (3) were presented. The obtained results indicated that the mechanisms of action of (1) and (3) occurred through different routes. The results support that the flavonoids derived from S. paludosum can become lead molecules for the design of antileishmanial prototypes.


Assuntos
Antiprotozoários/farmacologia , Morte Celular/efeitos dos fármacos , Flavonoides/farmacologia , Citometria de Fluxo/métodos , Leishmania/efeitos dos fármacos , Animais , Antiprotozoários/química , Autofagia/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Flavonoides/química , Quempferóis/química , Quempferóis/farmacologia , Leishmania/citologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Camundongos , Análise Espectral Raman , Estreptófitas/química
17.
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
18.
J Agric Food Chem ; 67(30): 8339-8347, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31291543

RESUMO

The dried seeds of Cuminum cyminum L. have been traditionally used as food and medicine. To explore its chemical composition and anti-inflammatory activity, four new compounds (1-4) along with five known compounds (5-9) were isolated from the seeds in the present study. The chemical structures of the new compounds were identified as follows: methyl 3-((7H-purin-2-yl) amino)-3-(4-isopropylphenyl) propanoate (1), 8-(amino(4-isopropylphenyl)methyl)-5-hydroxy-2-(4-hydroxyphenyl)-7-methoxy-4-oxo-4H-chromene-6-carboxylic acid (2), (3,4,5-trihydroxy-6-((4-isopropylbenzyl)oxy)tetrahydro-2H-pyran-2-yl)methyl (E)-3-(4-propoxyphenyl)acrylate (3), and (3,4,5-trihydroxy-6-((5-hydroxy-2-(4-hydroxyphenyl)-4-oxo-4H-chromen-7-yl)oxy)tetrahydro-2H-pyran-2-yl)methyl 3-(4-isopropylphenyl)-2-methoxypropanoate (4). Compound 2, an atypical nitrogen-containing flavonoid, exhibited the most active inhibitory effect on nitride oxide, with IC50 of 5.25 µM in the lipopolysaccharide-stimulated RAW264.7 cell assay. Compound 2 was found to suppress the expression levels of inducible nitric oxide synthase and cyclooxygenase-2. Furthermore, it was revealed that both nuclear factor κB and mitogen-activated protein kinase were involved in the anti-inflammatory process of compound 2.


Assuntos
Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Cuminum/química , Flavonoides/química , Flavonoides/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Frutas/química , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/imunologia , Estrutura Molecular , NF-kappa B/genética , NF-kappa B/imunologia , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/imunologia , Células RAW 264.7 , Sementes/química
19.
Food Chem ; 299: 125094, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31301529

RESUMO

The jaggery-making process involves various thermo-chemical treatments of sugarcane juice. As jaggery making is a traditional practice, knowledge about the use of different chemicals in the process is transferred from generation to generation without much scientific understanding. Phosphoric acid is one of the chemicals commonly used in this process. We have investigated its effect through systematic experiments. The addition of acid causes inversion of sucrose, which beyond a certain point is not desirable for good quality jaggery. In the correct proportions, however, phosphoric acid improves the colour and texture of jaggery and helps in the formation of smaller sized crystals. Reducing sugars formed due to inversion hinder crystal growth, resulting in relatively small crystals. In our experiments, the average crystal size reduced from 22.22 µm to 14.34 µm. Acid-treatedjaggery was found to equilibrate at higher moisture. A comparison with normal jaggery is thus provided for its keeping quality.


Assuntos
Indústria de Processamento de Alimentos/métodos , Ácidos Fosfóricos/química , Extratos Vegetais/química , Saccharum/química , Cor , Cristalização , Flavonoides/química , Monossacarídeos/análise , Extratos Vegetais/análise , Polifenóis/química
20.
Chem Pharm Bull (Tokyo) ; 67(7): 640-647, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31257319

RESUMO

Neuroinflammation manifested by over-activation of microglial cells plays an essential role in neurodegenerative diseases. Short-term activation of microglia can be beneficial, but chronically activated microglia can aggravate neuronal dysfunction possibly by secreting potentially cytotoxic substances such as tumor necrosis factor-alpha (TNF-α) and nitric oxide (NO), which can result in dysfunction and death of neurons. Therefore inhibiting over-activation of microglia and the production of cytotoxic intermediates may become an effective therapeutic approach for neuroinflammation. In this paper, we review our continuous research on natural inhibitors of over-activated microglia from traditional herbals, including flavonoids, lignans, sesquiterpene coumarins, and stilbenes.


Assuntos
Produtos Biológicos/química , Microglia/metabolismo , Animais , Produtos Biológicos/farmacologia , Cumarínicos/química , Cumarínicos/farmacologia , Flavonoides/química , Flavonoides/farmacologia , Lignanas/química , Lignanas/farmacologia , Microglia/citologia , Microglia/efeitos dos fármacos , Óxido Nítrico/biossíntese , Estilbenos/química , Estilbenos/farmacologia , Relação Estrutura-Atividade , Fator de Necrose Tumoral alfa/metabolismo
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