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Id: biblio-1048922
Autor: Kobus-Cisowska, Joanna; Szymanowska, Daria; Maciejewska, Paulina; Kmiecik, Dominik; Gramza-Michalowska, Anna; Kulczynski, Bartosz; Cielecka-Piontek, Judyta.
Título: In vitro screening for acetylcholinesterase and butyrylcholinesterase inhibition and antimicrobial activity of chia seeds (Salvia hispanica)
Fonte: Electron. j. biotechnol;37:1-10, Jan. 2019. tab, graf, ilus.
Idioma: en.
Resumo: BACKGROUND: Chia seeds are gaining increasing interest among food producers and consumers because of their prohealth properties. RESULTS: The aim of this work was to evaluate the potential of chia seeds to act as acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitors. The highest inhibitory activity against AChE and BChE was observed for colored seed ethanol extracts. A positive correlation was found between the presence of quercetin and isoquercetin as well as protocatechuic, hydroxybenzoic, and coumaric acids and the activity of extracts as AChE and BChE inhibitors. It has also been shown that grain fragmentation affects the increase in the activity of seeds against cholinesterases (ChE). Furthermore, seeds have been shown to be a source of substances that inhibit microbial growth. CONCLUSIONS: It was found that the chia seed extracts are rich in polyphenols and inhibit the activity of ChEs; therefore, their use can be considered in further research in the field of treatment and prevention of neurodegenerative diseases.
Descritores: Sementes/química
Butirilcolinesterase
Inibidores da Colinesterase
Salvia/química
Anti-Infecciosos/metabolismo
-Técnicas In Vitro
Flavonóis/análise
Compostos Fenólicos/análise
Polifenóis/análise
Aditivos Alimentares
Responsável: CL1.1 - Biblioteca Central


  2 / 12 LILACS  
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Id: biblio-950733
Autor: Cetin, Emine Sema.
Título: Induction of secondary metabolite production by UV-C radiation in Vitis vinifera L. Öküzgözü callus cultures
Fonte: Biol. Res;47:1-7, 2014. tab.
Idioma: en.
Resumo: BACKGROUND: The aim of the present work was to examine the role of UV-C irradiation on the production of secondary metabolites (total phenolic, total flavanols, total flavonols, catechin, ferulic acid and trans-resveratrol in phenolic compounds and α-, ß-, γ- δ-tocopherols) in callus cultures. Studies on the effects of UV-C treatment on callus culture are seldom and generally focused on UV-B. However UV-C radiation play an important role in accumule secondary metabolites. RESULTS: In this study, callus cultures from Öküzgözü grape cultivar were initiated from leaf petiole explants. Calli formed after 6 weeks on the medium supplemented with 0.5 mg L-1 benzylaminopurine (BA), 0.5 mg L-1 indole acetic acid (IAA) on B5 media. Callus tissues were exposed to UV-C irradiation at 10, 20 and 30 cm distances from the UV source for 5 and 10 minutes and samples were collected at hours 0, 24 and 48. CONCLUSIONS: The greatest total phenolic content (155.14 mg 100 g-1) was detected in calli exposed to UV-C for 5 min from 30 cm distance and sampled after 24 h. 24 h and 48 h incubation times, 30 cm and 5 min were the most appropriate combination of UV-C application in total flavanol content. Maximum total flavonol content (7.12 mg 100 g-1) was obtained on 0 h, 5 min and 20 cm combination. The highest (+)- catechin accumulation (8.89 mg g-1) was found in calli with 10 min UV-C application from 30 cm distance and sampled after 48 h. Ferulic acid content increased 6 fold in Öküzgözü callus cultures (31.37 µg g-1) compared to the control group. The greatest trans-resveratrol content (8.43 µg g-1) was detected in calli exposed to UV-C for 5 min from 30 cm distance and sampled after 24 h. The highest α-tocopherol concentration was found in calli exposed to UV-C for 10 min from 30 cm distance and sampled after 24 h. As a conclusion, it was showed that UV-C radiation had remarkable promoting effects on the accumulation of secondary metabolites in the calli of Öküzgözü grape cultivar.
Descritores: Raios Ultravioleta
Folhas de Planta/efeitos da radiação
Produtos Agrícolas/efeitos da radiação
Vitis/efeitos da radiação
Técnicas de Embriogênese Somática de Plantas/métodos
Metabolismo Secundário/efeitos da radiação
-Fenóis/análise
Estilbenos/análise
Flavonoides/análise
Catequina/análise
Cromatografia
Folhas de Planta/metabolismo
Folhas de Planta/química
Produtos Agrícolas/fisiologia
Ácidos Cumáricos/análise
Vitis/metabolismo
Vitis/química
Tocoferóis/análise
Flavonóis/análise
Metabolismo Secundário/fisiologia
Resveratrol
Responsável: CL1.1 - Biblioteca Central


  3 / 12 LILACS  
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Id: biblio-950743
Autor: Cetin, Emine Sema; Babalik, Zehra; Hallac-Turk, Filiz; Gokturk-Baydar, Nilgun.
Título: The effects of cadmium chloride on secondary metabolite production in Vitis vinifera cv. cell suspension cultures
Fonte: Biol. Res;47:1-6, 2014. graf, tab.
Idioma: en.
Resumo: BACKGROUND: Plant secondary metabolites are possess several biological activities such as anti-mutagenic, anti-carcinogenic, anti-aging, etc. Cell suspension culture is one of the most effective systems to produce secondary metabolites. It is possible to increase the phenolic compounds and tocopherols by using cell suspensions. Studies on tocopherols production by cell suspension cultures are seldom and generally focused on seed oil plants. Although fresh grape, grape seed, pomace and grape seed oil had tocopherols, with our best knowledge, there is no research on tocopherol accumulation in the grape cell suspension cultures. In this study, it was aimed to determine the effects of cadmium chloride treatments on secondary metabolite production in cell suspension cultures of grapevine. Cell suspensions initiated from callus belonging to petiole tissue was used as a plant material. Cadmium chloride was applied to cell suspension cultures in different concentration (1.0 mM and 1.5 mM) to enhance secondary metabolite (total phenolics, total flavanols, total flavonols, trans-resveratrol, and α-, ß-, γ- δ-tocopherols) production. Cells were harvested at two days intervals until the 6th day of cultures. Amounts of total phenolics, total flavanols and total flavonols; trans-resveratrol and tocopherols (α-, ß-, γ- and δ-tocopherols) and dry cell weights were determined in the harvested cells. RESULTS: Phenolic contents were significantly affected by the sampling time and cadmium concentrations. The highest values of total phenolic (168.82 mg/100 g), total flavanol (15.94 mg/100 g), total flavonol (14.73 mg/100 g) and trans-resveratrol (490.76 µg/100 g) were found in cells treated with 1.0 mM CdCl2 and harvested at day 2. Contents of tocopherols in the cells cultured in the presence of 1.0 mM CdCl2 gradually increased during the culture period and the highest values of α, ß and γ tocopherols (145.61, 25.52 and 18.56 µg/100 g) were detected in the cell cultures collected at day 6. CONCLUSIONS: As a conclusion, secondary metabolite contents were increased by cadmium chloride application and sampling time, while dry cell weights was reduced by cadmium chloride treatments.
Descritores: Cloreto de Cádmio/farmacologia
Vitis/efeitos dos fármacos
Cultura Primária de Células/métodos
Metabolismo Secundário/efeitos dos fármacos
-Fenóis/análise
Estilbenos/análise
Flavonoides/análise
Folhas de Planta/crescimento & desenvolvimento
Folhas de Planta/efeitos dos fármacos
Folhas de Planta/metabolismo
Folhas de Planta/química
Vitis/crescimento & desenvolvimento
Vitis/metabolismo
Vitis/química
Tocoferóis/análise
Flavonóis/análise
Proliferação de Células/efeitos dos fármacos
Técnicas de Embriogênese Somática de Plantas/métodos
Resveratrol
Responsável: CL1.1 - Biblioteca Central


  4 / 12 LILACS  
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Id: biblio-1146008
Autor: Dobrecky, Cecilia B.
Título: Variación de los perfiles de polifenoles en Ligaria cuneifolia (R. et. P) Tiegh (Loranthaceae), su estudio mediante electroforesis capilar y su relación con la actividad farmacológica. / Polyphenolic profile variation in Ligaria cuneifolia (R. et P.) Tiegh (Loranthaceae), capillary electrophoretic analysis and its relationship with the pharmacological activity
Fonte: Bol. latinoam. Caribe plantas med. aromát;36(1):5-10, 2020. ilus, Graf.
Idioma: es.
Resumo: Ligaria cuneifolia (R. et P.) Tiegh. ­Loranthaceae­ es una especie hemiparásita que se desarrolla sobre diferentes hospedantes. Es conocida con el nombre vulgar de "liga" o "liguilla". Debido a su similitud morfológica, constituye el sustituto natural del "muérdago europeo", por lo cual es denominado "muérdago criollo". Las drogas vegetales son matrices complejas en las cuales múltiples componentes actúan en forma sinérgica y son responsables de la acción farmacológica. Con el fin de dar sustento científico al uso folclórico de L. cuneifolia se estudiaron distintas formas de obtención de los extractos, se evaluaron diferentes hospedantes y regiones fitogeográficas. Se desarrolló y validó un método de electroforesis capilar para construir fingerprints o perfiles cromatográficos característicos que permitan evaluar los distintos componentes con el fin de estandarizar los extractos. Se efectuó la comparación con otras técnicas cromatográficas, tales como en cromatografía en capa delgada (TLC) y líquida de alta resolución (HPLC). A su vez, se procedió al aislamiento, purificación y análisis estructural de los compuestos de interés por técnicas espectroscópicas y cromatográficas. Se identificaron diez compuestos, de los cuales cuatro son reportados por primera vez en esta especie. La electroforesis capilar probó ser una técnica adecuada para el control de calidad de los extractos y una alternativa atractiva a las técnicas cromatográficas tradicionales.

Ligaria cuneifolia (R. et P.) Tiegh. ­Loranthaceae­ is a hemiparasite plant which grows on different host trees. It is popularly referred to as "liga" or "liguilla". Due to its morphological similarity, it is considered as the natural substitute for the European mistletoe, for which is known as the "Argentine mistletoe". Herbal drugs are complex matrices in which multiple components acting synergistically are responsible for the pharmacological activity. In order to provide scientific support to the popular use of L. cuneifolia, a capillary electrophoretic method was developed and validated to build a chromatographic profile or fingerprint that allows the evaluation of different components for extract standardization. A comparison was made with other chromatographic techniques such as TLC and HPLC. Isolation, purification and structural analysis of compounds were performed by chromatographic and spectroscopic methods. Ten analytes were identified, four of which are reported for the first time in L. cuneifolia. Capillary electrophoresis proved to be an appropriate tool for the quality control of herbal drugs, as well as an attractive alternative to traditional chromatographic techniques.
Descritores: Eletroforese Capilar
Loranthaceae
-Erva-de-Passarinho
Cromatografia em Camada Delgada
Flavonóis
Responsável: BR1.1 - BIREME


  5 / 12 LILACS  
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Id: biblio-1140534
Autor: Carrillo Alvarado, Sergio Daniel.
Título: Cuantificación de los compuestos bioactivos y capacidad antioxidante del hongo Cordyceps sinensis para su uso potencial como aditivo alimentario / Quantification of the bioactive compounds and antioxidant capacity of the Cordyceps sinensis fungus for its potential use as a food additive.
Fonte: Zamorano; s.n; 2019. 1-36 p. tab, graf.
Idioma: es.
Tese: Apresentada a Escuela Agrícola Panamericana para obtenção do grau de Licenciado.
Resumo: El uso de antioxidantes contribuye a disminuir el deterioro de los alimentos. Una práctica común en la actualidad es el uso de aditivos alimentarios de origen sintético, como el butilhidroxitolueno (BHT) y butilhidroxianisol (BHA). El hongo Cordyceps sinensis es ampliamente usado en la medicina asiática y se ha encontrado que aporta múltiples beneficios. Con el fin de evaluar la capacidad antioxidante de este hongo como aditivo alimentario, se obtuvieron extractos a partir de harina de C. sinensis, utilizando extracto acuoso (T1), etanólico (T2), acuoso-etanólico (T3) y acuoso a 50 °C (T4) (en una relación soluto/solvente de 100 g/900 mL c/u). Para la harina se determinó la composición química proximal, obteniendo alto contenido de carbohidratos (80%), y valores bajos de humedad, proteína, grasa y cenizas (<10%). Se determinó el contenido de fitoquímicos, incluyendo contenido de polisacáridos totales (CPT), fenoles totales (CFT), flavonoides totales (CFvT), flavonas y flavonoles totales (CFFT), flavanonas y dihidroflavonoles totales (CFDT), y ácido clorogénico (CAC). Además, actividad antirradical DPPH y ABTS, así como poder reductor (PR). Los resultados indicaron que el extracto T3, seguido del extracto T1, presentaron la mayor capacidad antioxidante (DPPH. ABTS y PR), lo cual fue asociado con el CFT, CFFT, y CFDT, así como CPT, CFvT y CAC, respectivamente. Se recomienda evaluar el efecto de la adición de los extractos obtenidos de la harina de C. sinensis sobre la estabilidad oxidativa y microbiológica de productos cárnicos.
Descritores: Fenóis
Cordyceps/química
Flavanonas
Flavonóis
Aditivos Alimentares
-Compostos Fitoquímicos
Medicina Tradicional
Antioxidantes
Limites: Humanos
Responsável: BR1.1 - BIREME


  6 / 12 LILACS  
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Id: lil-620815
Autor: Martins, Márcia Cristina Teixeira; Rodriguez-Amaya, Delia; Morgano, Marcelo Antonio; Rodrigues, Maria Isabel.
Título: Otimização e validação de metodologia analítica para determinação de flavonóis e flavonas por CLAE em pólen apícola utilizando-se análise de superfície de resposta / Optimization and validation of HPLC methodology for determining flavonols and flavones in bee pollen by surface methodology
Fonte: Rev. Inst. Adolfo Lutz;70(2):122-131, abr.-jun. 2011. tab, graf, ilus.
Idioma: pt.
Resumo: Foi otimizada a metodologia analítica para determinar quatro flavonóis: miricetina (M), quercetina (Q), kanferol (K) e isoramnetina (I); e duas flavonas: luteolina (L) e apigenina (A) em amostras de pólen apícola desidratado produzidas em três estados brasileiros: Bahia (BA), São Paulo (SP) e Santa Catarina (SC). Delineamento Composto Central Rotacional (DCCR) foi utilizado para investigar os efeitos da concentração de HCl e do tempo de hidrólise sobre a concentração de cada flavonoide. A condição ótima encontrada para extração/hidrólise dos flavonoides estudados foi: 1,0M HCl/30 minutos. A melhor separação dos flavonoides foi conseguida com a coluna de fase reversa Symmetry C18 e fase móvel de metanol: tetrahidrofurano: água(26:57:17), acidificados com 0,3 de ácido fórmico em corrida isocrática (CLAE). As curvas-padrão apresentaram coeficientes de correlação superiores a 0,99. Os limites de detecção foram de 1,04, 0,88, 0,89,1,64, 0,82 e 1,19 μg/mL respectivamente para M, L, Q, A, I e K.
Descritores: Flavonas
Flavonóis
Pólen
Tipo de Publ: GOVERNMENT PUBLICATIONS
Responsável: BR91.2 - Centro de Documentação


  7 / 12 LILACS  
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Id: lil-477256
Autor: Huber, Lísia S; Rodriguez-Amaya, Delia B; Rodrigues, Maria I.
Título: Otimização e validação de metodologia analitica para determinação de flavonóis e flavonas por CLAE em hortaliças / Optimization and validation of HPLC methodology for determining flavonols and flavones in vegetables
Fonte: Rev. Inst. Adolfo Lutz;66(2):142-151, maio-ago. 2007. tab, graf.
Idioma: pt.
Resumo: O objetivo deste trabalho foi otimizar a metodologia analítica para determinação de flavonóis e flavonas em hortaliças. A hidrólise foi otimizada utilizando-se Delineamento Composto Central Rotacional (DCCR)para investigar os efeitos da concentração de HCl e do tempo de hidrólise. Essa etapa foi realizada simultaneamente com a extração por metanol aquoso 50%, em refluxo a 90ºC. Foi utilizado cromatógrafo líquido Waters com coluna Nova-Pak C18 e detector de arranjo de diodos. Os compostos estudados foram miricetina (M), quercetina (Q), kaempferol (K), luteolina (L) e apigenina (A). As condições ótimas encontradas para hidrólise de cada hortaliça foram: 1,0M HCl/6 horas para espinafre e couve, 1,6M HCl/5 horas para rúcula, 1,2M HCl/2 horas para alface, 1,7M HCl/4,3 horas para salsa e 0,8M HCl/2,5 horas para cebola. O melhor gradiente para separação (CLAE) dos flavonóides das hortaliças em estudo foi constituído de metanol:água (acidificados com 0,3% de ácido fórmico) 20:80, chegando a 45:55 em 5 minutos, 48:52 em 17 minutos e voltando a 20:80 em 20 minutos. As curvas analíticas apresentaram coeficientes de correlação maiores que 0,99. Os limites de detecção foram de 0,5, 0,4, 0,5, 0,6 e 1,0μg/mL, respectivamente, para M, Q, L, K e A.

The objective of this investigation was to optimize the analytical methodology for determining flavonols and flavones in vegetables. The hydrolysis procedure was optimized using Central Composite Rotational Design (CCRD) to investigate the effects of HCl concentration and hydrolysis time. This step was carried out simultaneously with extraction with 50% aqueous methanol, and refluxing at 90°C. A Waters liquid chromatograph, with Nova-Pak C18 column and photodiode array detector, was used. The analyzed compounds were myricetin (M), quercetin (Q), kaempferol (K), luteolin (L), and apigenin (A). The optimum conditions found for hydrolysis for each vegetable were: 1.0M HCl for 6 hours for spinach and kale, 1.6M HCl for 5 hours for roquette, 1.2M HCl for 2 hours for lettuce, 1.7M HCl for 4.3 hours for parsley, and 0.8M HCL for 2.5 hours for onion. The best gradient (HPLC) for separating flavonoids from these vegetables consisted of methanol:water (acidified with 0.03% formic acid) 20:80, changing to 45:55 in 5 minutes, 48:52 in 17 minutes, returning to 20:80 in 20 minutes. The standard curves of the flavonoids had coefficients of correlation higher than 0.99. The detection limits were 0.5, 0.4, 0.5, 0.6 and 1.0μg/mL for M, Q, L, K, and A, respectively.
Descritores: Flavonoides
Flavonóis
Plantas
-Cromatografia Líquida de Alta Pressão
Responsável: BR91.2 - Centro de Documentação


  8 / 12 LILACS  
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Id: biblio-889202
Autor: Dsouza, Dorin; Nanjaiah, Lakshmidevi.
Título: Antibacterial activity of 3, 3', 4'-Trihydroxyflavone from Justicia wynaadensis against diabetic wound and urinary tract infection
Fonte: Braz. j. microbiol;49(1):152-161, Jan.-Mar. 2018. tab, graf.
Idioma: en.
Resumo: ABSTRACT The present investigation was designed to study the effect of an active compound isolated from Justicia wynaadensis against multi drug resistant organisms (MDRO's) associated with diabetic patients. The drug resistant pathogens implicated in wound and urinary tract infection of diabetic patients were isolated and identified by molecular sequencing. Solvent-solvent fractionation of crude methanol extract produced hexane, chloroform, ethyl acetate and methanol-water fraction, among which chloroform fraction was found to be potent when compared with other three fractions. Further, chloroform fraction was subjected to preparatory HPLC (High-Performance Liquid Chromatography), that produced four sub-fractions; chloroform HPLC fraction 1 (CHF1) through CHF4. Among the sub-fractions, CHF1 inhibited the pathogens effectively in comparison to other three sub-fractions. The purity of CHF1 was found to be >95%. Therefore, CHF1 was further characterized by NMR and FTIR analysis and based on the structure elucidated, the compound was found to be 3,3',4'-Trihydroxyflavone. The effective dose of this bioactive compound ranged from 32 µg/mL to 1.2 mg/mL. Thus, the present study shows that 3,3',4'-Trihydroxyflavone isolated from J. wynaadensis is an interesting biopharmaceutical agent and could be considered as a source of antimicrobial agent for the treatment of various infections and used as a template molecule for future drug development.
Descritores: Antibacterianos/farmacologia
Bactérias/efeitos dos fármacos
Complicações do Diabetes/microbiologia
Flavonóis/farmacologia
Justicia, Planta/química
Extratos Vegetais/farmacologia
Infecções Urinárias/microbiologia
Ferimentos e Lesões/microbiologia
-Antibacterianos/química
Antibacterianos/isolamento & purificação
Fenômenos Fisiológicos Bacterianos
Bactérias/genética
Bactérias/isolamento & purificação
Flavonóis/química
Flavonóis/isolamento & purificação
Testes de Sensibilidade Microbiana
Extratos Vegetais/química
Extratos Vegetais/isolamento & purificação
Folhas de Planta/química
Limites: Humanos
Responsável: BR1.1 - BIREME


  9 / 12 LILACS  
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Id: lil-648055
Autor: Urzúa, Alejandro; Echeverría, Javier; Espinoza, Javier; Wilkens, Marcela.
Título: Lipophilicity and antibacterial activity of flavonols: antibacterial activity of resinous exudates of Haplopappus litoralis, H. chrysantemifolius and H. scrobiculatus / Lipofilia y actividad antibacteriana de flavonoles: actividad antibacteriana de los exudados resinosos de Haplopappus litoralis, H. chrysantemifolius y H. scrobiculatus
Fonte: Bol. latinoam. Caribe plantas med. aromát;11(4):369-376, jul. 2012. tab, ilus.
Idioma: en.
Resumo: The antibacterial properties of the resinous exudates from Haplopappus litoralis, H. chrysantemifolius and H. scrobiculatus from Central Chile were assessed against Gram negative and Gram-positive bacteria, and proved active against the latter. The results show that the antibacterial activities of the resinous exudates are independent from the flavonols isolated from each extract that proved to be inactive. The estimated lipophilicity of the flavonols isolated from the Haplopappus resinous exudates were compared with the lipophilicity of known antibacterial flavonols. This analysis showed that lipophilicity is an important variable to predict the antibacterial activity of flavonols.

La actividad antibacteriana de los exudados resinosos de Haplopappus litoralis, H. chrysantemifolius y H. scrobiculatus de la Zona Central de Chile fueron evaluadas frente a bacterias Gram-negativas y Gram-positivas, y resultaron activos frente a estas últimas. Los resultados mostraron que la actividad antibacteriana de los exudados resinosos es independiente de los flavonoles aisladas de cada extracto que no mostraron actividad antibacteriana. La lipofilia estimada de los flavonoles aislados de los exudados resinosos de Haplopappus se comparó con la lipofilia de conocidos flavonoles antibacterianos. Este análisis mostró que la lipofilia es una variable importante para predecir la actividad antibacteriana de los flavonoles.
Descritores: Anti-Infecciosos
Bactérias
Extratos Vegetais/farmacologia
Extratos Vegetais/química
Flavonóis/isolamento & purificação
Haplopappus/química
-Bactérias Gram-Negativas
Bactérias Gram-Positivas
Chile
Flavonóis/farmacologia
Análise Espectral
Responsável: CL1.1 - Biblioteca Central


  10 / 12 LILACS  
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Id: lil-595812
Autor: Scotti, Luciana; Fernandes, Mariane Balerine; Muramatsu, Eric; Emereciano, Vicente de Paula; Tavares, Josean Fechine; Silva, Marcelo Sobral da; Scotti, Marcus Tullius.
Título: 13C NMR spectral data and molecular descriptors to predict the antioxidant activity of flavonoids / Dados espectrais de RMN 13C e descritores moleculares para prever a atividade antioxidante dos flavonóides
Fonte: Braz. j. pharm. sci;47(2):241-249, Apr.-June 2011. ilus, tab.
Idioma: en.
Resumo: Tissue damage due to oxidative stress is directly linked to development of many, if not all, human morbidity factors and chronic diseases. In this context, the search for dietary natural occurring molecules with antioxidant activity, such as flavonoids, has become essential. In this study, we investigated a set of 41 flavonoids (23 flavones and 18 flavonols) analyzing their structures and biological antioxidant activity. The experimental data were submitted to a QSAR (quantitative structure-activity relationships) study. NMR 13C data were used to perform a Kohonen self-organizing map study, analyzing the weight that each carbon has in the activity. Additionally, we performed MLR (multilinear regression) using GA (genetic algorithms) and molecular descriptors to analyze the role that specific carbons and substitutions play in the activity.

Danos aos tecidos devido ao estresse oxidativo estão diretamente ligados ao desenvolvimento de muitos, senão todos, os fatores de sedentarismo e de doenças crônicas. Neste contexto, a busca de moléculas naturais, que participam da nossa dieta e que possuam atividade antioxidante, flavonóides, torna-se de grande interesse. Neste estudo, nós investigamos um conjunto de 41 flavonóides (23 flavonas e 18 flavonóis), relacionando suas estruturas e atividade antioxidante. Os dados experimentais foram submetidos à análise de QSAR (relações quantitativas estrutura-atividade). Dados de RMN 13C foram utilizados para realizar um estudo do mapa auto-organizável de Kohonen, analisando o peso que cada carbono tem na atividade. Além disso, realizamos uma MLR (regressão múltipla) usando GA (algoritmos genéticos) e descritores moleculares para avaliar a influência de carbonos e substituições na atividade.
Descritores: Antioxidantes/química
Espectroscopia de Ressonância Magnética/métodos
Flavonoides/análise
Flavonoides/química
Relação Estrutura-Atividade
-Flavonas/análise
Flavonas/química
Flavonóis/análise
Flavonóis/química
Estrutura Molecular
Tipo de Publ: Estudo de Avaliação
Responsável: BR40.1 - DBD - Divisão de Biblioteca e Documentacão do Conjunto das Químicas



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