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Tronchuda cabbage flavonoids uptake by Pieris brassicae

Ferreres, F.; Sousa, C.; Valentão, P.; Pereira, J.A.; Seabra, R.M.; Andrade, P.B.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
ENG
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The flavonoid pattern of larvae of cabbage white butterfly (Pieris brassicae L.; Lepidoptera: Pieridae) reared on the leaves of tronchuda cabbage was analysed by HPLC-DAD-MS/MS-ESI. Twenty flavonoids were identified or characterised, namely 16 kaempferol and four quercetin derivatives. Kaempferol 3-O-sophoroside, a minor component of tronchuda cabbage, was found to be the main component in P. brassicae (15.8%). Apart from this, only two other flavonoids present in significant amounts in tronchuda cabbage (kaempferol 3-O-sophoroside-7-O-glucoside and kaempferol 3-O-sophoroside-7-O-sophoroside) were found in the larvae. The larvae have high amounts of quercetin derivatives (18.5%), which were present only in trace amounts in tronchuda cabbage extracts, suggesting that P. brassicae is able to selectively sequester these flavonoids. The occurrence of a high content of flavonoids not detectable in tronchuda cabbage extracts indicates that P. brassicae larvae are able to metabolize dietary flavonoids.

Effect of flavonoids on 2 `-deoxyguanosine and DNA oxidation caused by singlet molecular oxygen

CARNEIRO, Carlos D.; AMORIM, Juliana C.; CADENA, Silvia M. S. C.; NOLETO, Guilhermina R.; MASCIO, Paolo Di; ROCHA, Maria E. M.; MARTINEZ, Glaucia R.
Fonte: PERGAMON-ELSEVIER SCIENCE LTD Publicador: PERGAMON-ELSEVIER SCIENCE LTD
Tipo: Artigo de Revista Científica
ENG
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Antioxidant potential is generally investigated by assaying the ability of a compound to protect biological systems from free radicals. However, non-radical reactive oxygen species can also be harmful. Singlet molecular oxygen ((1)O(2)) is generated by energy transfer to molecular oxygen. The resulting (1)O(2) is able to oxidize the nucleoside 2`-deoxyguanosine (dGuo), which leads to the formation of 8-oxo-7,8-dihydro-2`-deoxyguanosine (8-oxodGuo) and spiroiminodihydantoin 2`-deoxyribonucleoside diastereomers (dSp) in an aqueous solution. The main objective of the present study was to verify whether the presence of flavonoids (flavone, apigenin, quercetin, morin and catechin) at different concentrations could protect dGuo from (1)O(2) damage. Of the tested flavonoids, flavone possessed antioxidant activity, as determined by a decrease in the formation of both products. Apigenin, morin, quercetin and catechin all increased the formation of 8-oxodGuo at a concentration of 100 mu M. The quantification of plasmid strand breaks after treatment with formamidopyrimidine-DNA glycosylase showed that flavone protected and quercetin and catechin enhanced DNA oxidation. Our results show that compounds, such as flavonoids, may affect the product distribution of (1)O(2)-mediated oxidation of dGuo...

Quantification of isoorientin and total flavonoids in Passiflora edulis fruit pulp by HPLC-UV/DAD

ZERAIK, M. L.; YARIWAKE, J. H.
Fonte: ELSEVIER SCIENCE BV Publicador: ELSEVIER SCIENCE BV
Tipo: Artigo de Revista Científica
ENG
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A method is reported for the quantification of isoorientin (using a standard addition method) and total flavonoids (expressed as rutin, using the external standard method) in passion fruit pulp (Passiflora edulis Sims f. flavicarpa Degener, Passifloraceae). Extraction of flavonoids was optimized by experimental design methodology, and quantitative analysis was performed by high-performance liquid chromatography with photo-diode array detection (HPLC-UV/DAD). The method was developed and validated according to ICH requirements for specificity, linearity, accuracy, precision (repeatability and intermediate precision). LOD and LOQ. Rutin was chosen as standard for the quantification of total flavonoids in order to propose a HPLC method feasible for routine analysis of the flavonoids in the passion fruit pulp. The passion fruit pulp contained 16.226 +/- 0.050 mg L(-1) of isoorientin and 158.037 +/- 0.602 mg L(-1) of total flavonoid, suggesting that P. edulis fruits may be comparable with other flavonoid food sources such as orange juice or sugarcane juice. (C) 2010 Elsevier B.V. All rights reserved.

Efeitos citoprotetor e/ou citotóxico dos flavonóides: estudo estrutura-atividade envolvendo mecanismos mitocondriais, com ênfase na apoptose; Protective/toxic effects of flavonoids: structure-activity study involving mitochondrial mechanisms, with emphasis on apoptosis.

Dorta, Daniel Junqueira
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 16/05/2007 PT
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Realizou-se um estudo estrutura-atividade sobre os efeitos citoprotetor/citotóxico de 5 flavonóides envolvendo processos mitocondriais, com ênfase na apoptose. Nossos resultados mostram que a dupla ligação na posição 2-3 / grupos 3-OH em conjugação com a função 4-oxo no anel C da estrutura dos flavonóides parece favorecer a interação destes compostos com a membrana mitocondrial, diminuindo a sua fluidez, e tanto inibindo a cadeia respiratória das mitocôndrias, quanto causando desacoplamento. Por outro lado, a estrutura o-di-OH no anel B parece favorecer a inibição da cadeia respiratória, sendo que a ausência desta estrutura parece favorecer a atividade desacopladora. Os flavonóides que não afetaram a respiração mitocondrial, induziram a transição de permeabilidade mitocondrial. A capacidade dos flavonóides em liberar o Ca2+ acumulado pelas mitocôndrias correlaciona-se com a sua capacidade de afetar a respiração mitocondrial e sua inabilidade em induzir a transição de permeabilidade mitocondrial. Já os dados referentes aos estudos da atividade protetora contra a formação de radicais livres demonstraram que a quercetina, luteolina e a galangina foram substancialmente mais potentes que a taxifolina e a catequina em conferir proteção contra a lipoperoxidação...

Mecanismo de ação de flavonóides no metabolismo oxidativo e na fagocitose de neutrófilos humanos desencadeados por receptores Fc-gama e CR; Mechanism of action of flavonoids in the human neutrophils oxidative burst and phagocytosis triggered by Fc gamma and CR receptors.

Santos, Éverton de Oliveira Lima dos
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 19/03/2010 PT
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O sistema imune inato é organizado por processos complexos que envolvem os diversos tipos celulares que culminam na eliminação de uma variedade de microorganismos a fim de proteger o organismo de infecções. Os neutrófilos são células importantes neste sistema, sendo capazes de migrar rapidamente ao foco da infecção. Estas células reconhecem e fagocitam partículas estranhas e atuam no sentido de elimina-los através da produção de espécies reativas de oxigênio (EROs), proteínas antimicrobianas e enzimas proteolíticas dos grânulos, que são liberadas no fagossomo e no espaço extracelular. Entretanto, em algumas doenças inflamatórias e autoimunes têm sido encontradas lesões nos tecidos envolvendo a produção excessiva de EROs pelos neutrófilos, desencadeada por imunocomplexos (ICs) via receptores Fc gama (Fc) e de complemento (CR). Assim, a modulação da ativação destes receptores e da produção de EROs é importante na manutenção da homeostasia. Nas últimas décadas, flavonóides são considerados como metabólitos secundários promissores mostrando atividade antioxidante e imunomodulatória. Neste trabalho foi avaliado o efeito modulatório dos flavonóides galangina, kaempferol, quercetina e miricetina em algumas funções efetoras de neutrófilos humanos...

Estudo analítico dos flavonoides dos frutos do maracujá (Passiflora edulis Sims f. flavicarpa Degener); Analytical studies of the flavonoids in passion fruit (Passiflora edulis Sims f. flavicarpa Degener)

Zeraik, Maria Luiza
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 16/04/2010 PT
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Atualmente tem-se dado grande ênfase aos alimentos funcionais, pois atuam na prevenção e auxiliam na recuperação de várias doenças, como doenças inflamatórias crônicas, cardiovasculares e câncer, por apresentarem principalmente flavonoides, que previnem lesões oxidativas, propiciando benefícios à saúde. O Brasil é o maior produtor mundial do maracujá, e em vista disto é de suma importância o desenvolvimento de métodos analíticos e estudos de atividade antioxidante e anti-inflamatória do fruto de maracujá, visando sua possível utilização como alimento funcional e produção de possíveis fármacos. Passiflora edulis Sims. f. flavicarpa Degener, conhecida como maracujá azedo ou amarelo é a espécie mais cultivada e comercializada no Brasil. Desta forma, os objetivos deste trabalho foram: desenvolver e validar um método analítico por CLAE-UV/DAD (cromatografia líquida de alta eficiência acoplada detector de arranjo de fotodiodos) para quantificação da flavona isoorientina, presente na polpa de P. edulis; quantificação dos flavonoides totais desta espécie, usando um padrão de baixo custo (rutina); comparar as técnicas CLAE e CCDAE (cromatografia em camada delgada de alta eficiência) e analisar a isoorientina nas cascas dos frutos de P. edulis infectada com o vírus PWV e cascas sadias por CCDAE; quantificar as proteínas totais e avaliar as atividades antioxidantes e anti-inflamatória dos extratos de cascas de P. edulis e da polpa dos frutos de P. edulis e P. alata...

Desenvolvimento e avaliação da estabilidade de formulações cosméticas anticelulíticas contendo o extrato comercial de Trichilia catiguá Adr. Juss (e) Ptychopetalum olacoides Bentham, padronizado em flavonóides totais; Development and stability assay of anticelulitic cosmetic formulations containing the Trichilia catigua Adr. Juss (e) Ptychopetalum olacoides Bentham commercial extract, standardized in total flavonoids

Baby, André Rolim
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 26/07/2005 PT
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A hidrolipodistrofia ginóide, popularmente denominada de celulite, é caracterizada como um processo distrófico que produz alterações estruturais dos elementos presentes na pele, como: modificações no tecido conjuntivo, comprometimento da microcirculação periférica cutânea, hipertrofia e hiperplasia dos adipócitos e edema. Os flavonóides são utilizados como substâncias ativas em preparações anticelulíticas por reduzirem a permeabilidade capilar. Os objetivos estabelecidos para esta pesquisa foram: (1) desenvolver emulsões cosméticas com finalidades anticelulíticas; (2) validar metodologia analítica para o doseamento de flavonóides totais, equivalentes em rutina, por espectrofotometria na região do ultravioleta; (3) avaliar a estabilidade física, físico-química e química das formulações. Formulações cosméticas anticelulíticas foram desenvolvidas contendo o extrato vegetal comercial de Trichilia catiguá Adr. Juss (e) Ptychopetalum olacoides Bentham (Slimbuster® H1), padronizado em flavonóides totais, equivalentes em rutina, e avaliadas quanto à estabilidade física, físico-química e química. Para sua quantificação, o método espectrofotométrico na região do ultravioleta a 361,0 nm foi empregado...

Dimorphandra mollis: An Alternative as a Source of Flavonoids with Antioxidant Action.

Hubinger, Silviane Z.; Cefali, Leticia C.; Vellosa, Jose C. R.; Salgado, Hérida Regina Nunes; Isaac, Vera L. B.; Moreira, Raquel R. D.
Fonte: Colegio Farmaceuticos Provincia de Buenos Aires Publicador: Colegio Farmaceuticos Provincia de Buenos Aires
Tipo: Artigo de Revista Científica Formato: 271-274
SPA
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Dimorphandra mollis: An Alternative as a Source of Flavonoids with Antioxidant Action. Dimorphandra molls fruits are rich in flavonoids rutin and quercetin, which are compounds with high antioxidant activity and can be used to prevent diseases caused by free radicals. The aim of this study was to obtain an extract rich in flavonoids from fruits of D. mollis. The extract was analyzed using the methods of determination by spectrophotometry and high performance liquid chromatography. The presence of rutin and quercetin was identified in the extract, which showed a total flavonoids content of 33.71 To. The extract also showed antioxidant activity as scanvanger of DPPH and ABTS radicals. It was possible to conclude that D. mollis fruits are a rich source of flavonoids with antioxidant action.

Electrochemical investigations on the capacity of flavonoids to protect DNA against damage caused by textile disperse dyes

Uliana, Carolina Venturini; Garbellini, Gustavo Stoppa; Yamanaka, Hideko
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 188-195
ENG
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Processo FAPESP: 09/08161-8; Processo FAPESP: 08/08990-1; Processo FAPESP: 08/10449-7; In previous work, the interaction of DNA with the textile dyes Disperse Orange 1 (DO1) and Disperse Red 1 (DR1), and their electrolysis products, resulted in significant changes in the characteristic oxidation peaks of the guanine and adenine moieties of immobilized dsDNA, measured using pencil graphite electrodes. In order to evaluate the protective capacity of flavonoids and teas against DNA damage caused by the dyes, studies of the interaction of DNA with DO1 and DR1 were conducted in the presence of the flavonoids myricetin and apigenin. The flavonoids were able to protect adenine and guanine from interaction with the dyes, as shown by smaller decreases in current intensity. Solutions of green tea and chamomile tea also showed protective capacities. Using interaction times of 180 s, the adenine moiety current intensity decreased by 60% of the initial value after interaction with 1.0 x 10(-5) mol L-1 DR1 alone, but by only 8% when the same DR1 concentration was employed in a mixture with 5.0 x 10(-7) mol L-1 myricetin...

Differences in the hydroxylation pattern of flavonoids alter their chemoprotective effect against direct- and indirect-acting mutagens

Resende, Flavia A.; Silva Almeida, Carolina P. da; Vilegas, Wagner; Varanda, Eliana A.
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 251-255
ENG
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); The antimutagenicity of ten flavonoids, differing in their hydroxylation patterns against direct-acting and indirect-acting mutagens, namely 4-nitro-o-phenylenediamine, sodium azide, mitomycin C, benzo[a]pyrene, aflatoxin B-1 and 2-aminofluorene, were compared with the aim of investigating how the hydroxyl groups in their structures govern the biological activity of flavonoids, by the Ames test, with Salmonella typhimurium strains TA98, TA100 and TA102. The flavonoids tested were: quercetin, kaempferol, luteolin, fisetin, chrysin, galangin, flavone, 3-hydroxyflavone, 5-hydroxyflavone and 7-hydroxyflavone. In these tests, all compounds were shown to be antimutagenic in more than one strain and various mechanisms of action were demonstrated. The results suggested that the number and position of hydroxyl groups may increase or decrease the protective effect, depending on the type and concentration of flavonoids and mutagen used. These studies contribute to clarifying the mechanisms by which these flavonoids act in protecting DNA from damage. This is required before they can be widely used. (C) 2014 Elsevier Ltd. All rights reserved.

Neuroprotection by flavonoids

Dajas,F.; Rivera-Megret,F.; Blasina,F.; Arredondo,F.; Abin-Carriquiry,J.A.; Costa,G.; Echeverry,C.; Lafon,L.; Heizen,H.; Ferreira,M.; Morquio,A.
Fonte: Associação Brasileira de Divulgação Científica Publicador: Associação Brasileira de Divulgação Científica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2003 EN
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The high morbidity, high socioeconomic costs and lack of specific treatments are key factors that define the relevance of brain pathology for human health and the importance of research on neuronal protective agents. Epidemiological studies have shown beneficial effects of flavonoids on arteriosclerosis-related pathology in general and neurodegeneration in particular. Flavonoids can protect the brain by their ability to modulate intracellular signals promoting cellular survival. Quercetin and structurally related flavonoids (myricetin, fisetin, luteolin) showed a marked cytoprotective capacity in in vitro experimental conditions in models of predominantly apoptotic death such as that induced by medium concentrations (200 µM) of H2O2 added to PC12 cells in culture. Nevertheless, quercetin did not protect substantia nigra neurons in vivo from an oxidative insult (6-hydroxydopamine), probably due to difficulties in crossing the blood-brain barrier. On the other hand, treatment of permanent focal ischemia with a lecithin/quercetin preparation decreased lesion volume, showing that preparations that help to cross the blood-brain barrier may be critical for the expression of the effects of flavonoids on the brain. The hypothesis is advanced that a group of quercetin-related flavonoids could become lead molecules for the development of neuroprotective compounds with multitarget anti-ischemic effects.

Isolation of flavonoids from Anemopaegma arvense (Vell) Stellf. ex de Souza and their antifungal activity against Trichophyton rubrum

Costanzo,Camila Di Giovane; Fernandes,Vanessa Colnaghi; Zingaretti,Sônia; Beleboni,Rene Oliveira; Pereira,Ana Maria Soares; Marins,Mozart; Taleb-Contini,Sílvia Helena; Pereira,Paulo Sérgio; Fachin,Ana Lúcia
Fonte: Universidade de São Paulo, Faculdade de Ciências Farmacêuticas Publicador: Universidade de São Paulo, Faculdade de Ciências Farmacêuticas
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2013 EN
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Anemopaegma arvense (Vell) Stellf. ex de Souza belongs to the family Bignoniaceae, and is popularly known as catuaba. To evaluate the cytotoxic and antimicrobial activity of A. arvense, fraction F3 and flavonoids 1 (quercetin 3-O-α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside) (rutin) and flavonoid 2 (quercetin 3-O-α-L-rhamnopyranosyl-(1→6)-β-D-galactopyranoside) were isolated from the leaves of this plant. Fraction F3 and flavonoids 1 and 2 exhibited no antibacterial activity. Furthermore, no cytotoxic activity of fraction 3 or flavonoids 1 and 2 was observed against the tumor cells tested. However, analysis of the antifungal activity of flavonoids 1 and 2 revealed minimum inhibitory concentrations of 0.5 and 0.25 mg/mL, respectively, against the Trichophyton rubrum strains tested (wild type and mutant). This study demonstrates for the first time the antifungal activity of isolated flavonoids, validating the same activity for A. arvense.

Protective effect of mulberry flavonoids on sciatic nerve in alloxan-induced diabetic rats

Song-Tao,Ma; Dong-lian,Liu; Jing-jing,Deng; Yan-juan,Peng
Fonte: Universidade de São Paulo, Faculdade de Ciências Farmacêuticas Publicador: Universidade de São Paulo, Faculdade de Ciências Farmacêuticas
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2014 EN
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Mulberry leaves (Morus alba L.) are a traditional Chinese medicine for blood serum glucose reduction. This study evaluated the protective effects of mulberry flavonoids on sciatic nerve in alloxan-induced diabetic rats. In this study, 80 Sprague-Dawley rats were divided into five groups: A (control), B (diabetic treated with saline), C-D (diabetic treated with 0.3, 0.1 g/kg mulberry flavonoids once a day for 8 weeks) and E (diabetic treated with 0.3 mg/kg methycobal). The diabetic condition was induced by intraperitoneal injection of 200 mg/kg alloxan dissolved in saline. At the end of the experimental period, blood, and tissue samples were obtained for biochemical and histopathological investigation. Treatment with 0.3 g/kg mulberry flavonoids significantly inhibited the elevated serum glucose (P< 0.01). The increased myelin sheath area (P< 0.01), myelinated fiber cross-sectional area and extramedullary fiber number (P< 0.05) were also reduced in alloxan-induced rats treated with 0.3 g/kg mulberry flavonoids. 0.3 g/kg mulberry flavonoids also markedly decreased onion-bulb type myelin destruction and degenerative changes of mitochondria and Schwann cells. These findings demonstrate that mulberry flavonoids may improve the recovery of a severe peripheral nerve injury in alloxan-induced diabetic rats and is likely to be useful as a potential treatment on peripheral neuropathy (PN) in diabetic rats.

Antioxidant effect of flavonoids after ascorbate/Fe2+-induced oxidative stress in cultured retinal cells

Areias, Filipe Miguel; Rego, A. Cristina; Oliveira, Catarina R.; Seabra, Rosa Maria
Fonte: Universidade de Coimbra Publicador: Universidade de Coimbra
Tipo: Artigo de Revista Científica Formato: aplication/PDF
ENG
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In this study, we investigated the structure-activity relationship of four flavonoids, i.e. eriodictyol, luteolin, quercetin, and taxifolin, in cultured retinal cells after ascorbate/Fe2+-induced oxidative stress. The relative order of antioxidant efficacy, determined by the thiobarbituric acid method, was the following: eriodictyol > quercetin > luteolin > taxifolin. Upon preincubation, the flavonoids were also effective in reducing the extent of lipid peroxidation. Oxidative stress, determined by the changes in fluorescence of 2',7'-dichlorodihydrofluorescein, was also decreased in the presence of the flavonoids, showing the following order of antioxidant efficacy: eriodictyol > taxifolin [approximate] quercetin > luteolin. Ascorbate/Fe2+-induced oxidative stress or incubation in the presence of the flavonoids did not significantly affect the viability of retinal cells. We also evaluated the degree of membrane partition of the flavonoids. In this system, the results strongly suggest that the higher antioxidant activity of the flavonoids is not correlated with the presence of a double bond at C2-C3 and/or a hydroxyl group at C3 on the C ring, but rather may depend on the capacity to inhibit the production of reactive oxygen species to interact hydrophobically with membranes. Eriodictyol was shown to be the most efficient antioxidant in protecting against oxidative stress induced by ascorbate/Fe2+ in the retinal cells.; http://www.sciencedirect.com/science/article/B6T4P-433NTS7-D/1/f92e0342be119c0ec4f7a436566bc7fd

Tronchuda cabbage flavonoids uptake by Pieris brassicae

Ferreres, Federico; Sousa, Carla; Valentão, Patricia; Pereira, José Alberto; Seabra, Rosa M.; Andrade, Paula B.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 259768 bytes; application/pdf
ENG
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7 pages, 4 tables, 4 figures.-- El PDF es la copia de autor.; The flavonoid pattern of larvae of cabbage white butterfly (Pieris brassicae L.; Lepidoptera: Pieridae) reared on the leaves of tronchuda cabbage was analysed by HPLC-DAD-MS/MS-ESI. Twenty flavonoids were identified or characterised, namely 16 kaempferol and four quercetin derivatives. Kaempferol 3-O-sophoroside, a minor component of tronchuda cabbage, was found to be the main component in P. brassicae (15.8%). Apart from this, only two other flavonoids present in significant amounts in tronchuda cabbage (kaempferol 3-O-sophoroside-7-O-glucoside and kaempferol 3-O-sophoroside-7-O-sophoroside) were found in the larvae. The larvae have high amounts of quercetin derivatives (18.5%), which were present only in trace amounts in tronchuda cabbage extracts, suggesting that P. brassicae is able to selectively sequester these flavonoids. The occurrence of a high content of flavonoids not detectable in tronchuda cabbage extracts indicates that P. brassicae larvae are able to metabolize dietary flavonoids.; [Graphical abstract]: The flavonoid pattern of larvae of cabbage white butterfly (Pieris brassicae L.; Lepidoptera: Pieridae) reared on the leaves of tronchuda cabbage was analysed by HPLC-DAD-MS/MS-ESI. Twenty kaempferol and quercetin derivatives were identified or characterised. The results suggest that P. brassicae is able to selectively sequester quercetin derivatives and to metabolize dietary flavonoids.; The authors are grateful to Fundaçäo para a Ciência e Tecnologia (PTDC/AGR-AAM/64150/2006) for financial support of this work.; Peer reviewed

Characterization of the interglycosidic linkage in di-, tri-, tetra- and pentaglycosylated flavonoids and differentiation of positional isomers by liquid chromatography/electrospray ionization tandem mass spectrometry

Ferreres, Federico; Llorach, Rafael; Gil-Izquierdo, Ángel
Fonte: John Wiley & Sons Publicador: John Wiley & Sons
Tipo: Artículo Formato: 259768 bytes; application/pdf
ENG
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10 pages, 4 figures, 5 tables.; The LC/UV-DAD/ESI-MSn negative fragmentation mode of 23 O-glycosylated flavonoids with two, three, four and five hexoses was studied. The results show that it is possible to differentiate the (1 2) and (1 6) interglucosidic linkages and also to discern between the flavonoid isomers with two glucoses (sophorosides, gentiobiosides and X,Y-diglucosides), three glucoses (sophorotriosides and X-sophoroside-Y-glucoside) and four glucoses (X-sophorotriosides-Y-glucoside and X-sophoroside-Y-sophoroside). In the characterization of the (1 2) and (1 6) interglycosidic linkages, the Y1- (-162 u) and Z1- (-180 u) ions play a relevant role. In the first case ions with high relative abundance (13-79%) are found, whereas in the other cases they are in very low abundance or absent. X,Y-di-O-glucoside flavonoids can be differentiated from the O-diglucoside flavonoids by the presence of Y1- (base peak) and Y0- (30%) ions and the absence of Z1- ions. Regarding flavonoids glycosylated with three glucoses, X-sophoroside-Y-glucoside flavonoids show the Y70- (-162 u) ion as the only peak in MS2 events whereas in sophorotrioside flavonoids various ions due to intermediate fragmentations are observed. These ions are characteristic of a (1 2) interglucosidic linkage. In MS2 experiments on flavonoids with four glucoses (X-sophorotrioside-Y-glucoside and X-sophoroside-Y-sophoroside)...

Flavonoids, phenolic acids and abscisic acid in Australian and New Zealand Leptospermum honeys

Yao, Liu H.; Datta, Nivedita; Tomás Barberán, Francisco; Martos, Isabel; Ferreres, Federico; Singanusong, Riantong
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 259768 bytes; application/pdf
ENG
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10 pages, 3 figures, 4 tables.; Flavonoids, phenolic acids and abscisic acid of Australian and New Zealand Leptospermum honeys were analyzed by HPLC. Fifteen flavonoids were isolated in Australian jelly bush honey (Leptospermum polygalifolium), with an average content of 2.22 mg/100 g honey. Myricetin (3,5,7,3′,4′,5′-hexahydroxyflavone), luteolin (5,7,3′,4′-tetrahydroxyflavone) and tricetin (5,7,3′,4′,5′-pentahydroxyflavone) were the main flavonoids identified. The mean content of total phenolic acids in jelly bush honey was 5.14 mg/100 g honey, with gallic and coumaric acids as the potential phenolic acids. Abscisic acid was quantified as twice the amount (11.6 mg/100 g honey) of the phenolic acids in this honey. The flavonoid profile mainly consisted of quercetin (3,5,7,3′,4′-pentahydroxyflavone), isorhamnetin (3,5,7,4′-tetrahydroxyflavone 3′-methyl ethyl), chrysin (5,7-dihydroxyflavone), luteolin and an unknown flavanone in New Zealand manuka (Leptospermum scoparium) honey with an average content of total flavonoids of 3.06 mg/100 g honey. The content of total phenolic acids was up to 14.0 mg/100 g honey, with gallic acid as the main component. A substantial quantity (32.8 mg/100 g honey) of abscisic acid was present in manuka honey. These results showed that flavonoids and phenolic acids could be used for authenticating honey floral origins...

Isolation of flavonoids from Anemopaegma arvense (Vell) Stellf. ex de Souza and their antifungal activity against Trichophyton rubrum

Costanzo, Camila Di Giovane; Fernandes, Vanessa Colnaghi; Zingaretti, Sônia; Beleboni, Rene Oliveira; Pereira, Ana Maria Soares; Marins, Mozart; Taleb-Contini, Sílvia Helena; Pereira, Paulo Sérgio; Fachin, Ana Lúcia
Fonte: Universidade de São Paulo. Faculdade de Ciências Farmacêuticas Publicador: Universidade de São Paulo. Faculdade de Ciências Farmacêuticas
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; ; Formato: application/pdf
Publicado em 01/09/2013 ENG
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Anemopaegma arvense (Vell) Stellf. ex de Souza belongs to the family Bignoniaceae, and is popularly known as catuaba. To evaluate the cytotoxic and antimicrobial activity of A. arvense, fraction F3 and flavonoids 1 (quercetin 3-O-α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside) (rutin) and flavonoid 2 (quercetin 3-O-α-L-rhamnopyranosyl-(1→6)-β-D-galactopyranoside) were isolated from the leaves of this plant. Fraction F3 and flavonoids 1 and 2 exhibited no antibacterial activity. Furthermore, no cytotoxic activity of fraction 3 or flavonoids 1 and 2 was observed against the tumor cells tested. However, analysis of the antifungal activity of flavonoids 1 and 2 revealed minimum inhibitory concentrations of 0.5 and 0.25 mg/mL, respectively, against the Trichophyton rubrum strains tested (wild type and mutant). This study demonstrates for the first time the antifungal activity of isolated flavonoids, validating the same activity for A. arvense.; Anemopaegma arvense pertence à família Bignoniaceae, sendo conhecida popularmente como Catuaba. Para avaliação de sua atividade citotóxica e antimicrobiana, a fração cromatográfica F3 e os flavonoides 1 (quercetina 3-O-α-L-ramnopiranosil-(1→6)-β-D-glucopiranosídeo) (rutina) e flavonoide 2 (quercetina 3-O-α-L-ramnopiranosil-(1→6)-β-D-galactopiranosídeo) foram isolados das folhas de A. arvense. A fração 3 e os flavonoides não apresentaram atividade antibacteriana. Nenhuma atividade citotóxica foi observada para a fração F3 e para os flavonoides...

ENZYME TRANSFORMATION OF FLAVONOIDS; TRANSFORMAÇÕES ENZIMÁTICAS DE FLAVONÓIDES

Aguiar, Claudio Lima de; Alencar, Severino Matias de; Tsai, Siu Mui; Park, Yong Kun
Fonte: UFPR Publicador: UFPR
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Formato: application/pdf
Publicado em 30/07/2007 POR
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A literature review about microbial and enzyme transformation of flavonoids was accomplished. Enzyme reactions, as well as, the action of microbial cells on flavonoids were discussed in seven distinct topics. The effects of these transformations were discussed for some reactions. The scientific literature has described that many microorganisms and enzymes possess the ability to metabolize plant flavonoids. Modified structures of flavonoids have been identified after microbial cultures or specific enzymatic reactions. Such alterations in their chemical structures, may produce flavonoids with higher biological activities (antioxidant, anti-inflammatory, antitumoral and antimicrobial).; Efetuou-se revisão da literatura sobre as transformações microbianas ou enzimáticas de flavonóides. Reações enzimáticas, bem como a ação de suspensões microbianas sobre flavonóides foram abordadas em sete tópicos. Os efeitos dessas transformações também foram discutidos para algumas reações. A literatura científica mostra que muitos microrganismos e enzimas apresentam a habilidade de metabolizar flavonóides amplamente distribuídos em vegetais. Estruturas modificadas dos flavonóides têm sido identificadas após culturas microbianas ou reações enzimáticas específicas. Tais alterações nas suas estruturas químicas podem produzir flavonóides com maior atividade biológica (antioxidante...

Anti-inflammatory properties of dietary flavonoids

González-Gallego,J.; Sánchez-Campos,S.; Tuñón,M. J.
Fonte: Nutrición Hospitalaria Publicador: Nutrición Hospitalaria
Tipo: info:eu-repo/semantics/article; journal article; info:eu-repo/semantics/publishedVersion Formato: text/html; application/pdf
Publicado em 01/06/2007 ENG
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Flavonoids are a group of natural substances that are located in sources of vegetal origin. More than 4,000 varieties of flavonoids have been identified. All of them are phenyl-benzopyrones of low molecular weight with a basic structure formed by two benzene rings united through a heterocyclic pyrane or pyrone. Besides their relevance in plants, flavonoids are important for human health. Their antioxidant capacity confers a therapeutic potential in cardiovascular diseases, gastric or duodenal ulcers, cancer or hepatic pathologies. Also important are their antiviral and anti-allergic actions, as well as their anti-thrombotic and anti-inflammatory properties. Prostaglandins and nitric oxide biosynthesis is involved in inflammation, and isoforms of inducible nitric oxide synthase (iNOS) and of cyclooxygenase (COX-2) are responsible for the production of a great amount of these mediators. It has been demonstrated that flavonoids are able to inhibit both enzymes, as well as other mediators of the inflammatory process such as reactive C protein or adhesion molecules. Modulation of the cascade of molecular events leading to the overexpression of those mediators include inhibition of transcription factors such as nuclear factor kappa B and AP-1...