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Biopharmaceutics and pharmacokinetics characterization of bioactive flavones in Scutellariae baicalensis Georgi. / CUHK electronic theses & dissertations collectionJanuary 2010 (has links)
Methods. The intestinal absorption and metabolism of W and OA as well as the potential interactions among B, Wand OA were investigated at in vitro, in situ and in vivo levels. Various models were employed including Caco-2 cell monolayer model, in vitro enzymatic kinetics study, rat in situ single-pass intestinal perfusion model and in vivo pharmacokinetic study in rats. / Purpose. Scutellariae baicalensis Georgi is a medicinal plant widely distributed in Asia. Its dried root, Radix Scutellariae (RS), has been extensively used in Chinese and Japanese medicine. Six flavones including baicalein (B), wogonin (W), oroxylin A (OA) and their corresponding glucuronic acid conjugates (BG, WG, OAG) are the major bioactive components in RS. Our previous studies on B revealed an extensive first-pass metabolism during its absorption. Hence, it is expected that W and OA which have the similar structures as B, may share similar absorption and metabolic pathways as B. The present project aims to (1) establish an assay method for better quality control of RS; (2) provide further biopharmaceutic characterizations ofW and OA in RS; (3) investigate the potential pharmacokinetic interactions among B, Wand OA. / Results. Similar to B, Wand OA showed favorable permeability in both the Caco-2 cell and the rat in situ single-pass perfusion models. However, they experienced extensive first-pass metabolism, mainly in the form of glucuronidation. Intracellularly formed WG and OAG could be effluxed to both the apical side (lumen side) and basolateral side (mesenteric blood side) mainly by MRPs, which was confirmed by inhibition transport studies in Caco-2 cells and transfected MDCK cells. The glucuronidation rate of OA was higher than that of W, which was observed by enzymatic kinetics studies by sub-cellular fractions with intrinsic clearances (Vmax/K m, mul/min/mg) of 456 to 4170 for W and 509∼5038 for OA. UGT 1A9 was the most potent metabolic enzyme for hepatic glucuronidation, while UGTs 1A8 and 1AlO were responsible for the intestinal glucuronidation of W and OA. The in vivo rat pharmacokinetics studies showed that W and OA may be readily absorbed and extensively metabolized with no parent compound detectable in blood after oral administration of W and OA. A new metabolite of W was identified to be the glucuronic acid conjugate at 5-0H of W. After co-administration of B, W and OA, decreased formation of BG, WG and OAG was observed in in vitro enzymatic kinetics study. Further studies in absorption models of Caco-2 cell monolayer and rat in situ single-pass intestinal perfusion demonstrated the enhancement in absorption of B, W and OA and decrease of BG, WG and OAG after the co-administration of B, W and OA. The ultimate pharmacokinetics interaction study revealed that glucuronides were the predominant form in systemic circulation and the AUC of OAG significantly increased after co-administration of B, Wand OA. Conclusion: Similar to B, Wand OA may be well absorbed followed by extensive first-pass metabolism, which was mediated by various UGT isozymes. During absorption, the intracellularly formed WG and OAG were mainly effluxed by MRPs to both the lumen and mesenteric blood side of the intestine. Both in vitro and in situ models indicated that interactions among B, W and OA would lead to decreased glucuronidation and increased absorption of parent flavones. Due to extensive metabolism in vivo, only glucuronides appeared in systemic circulation after co-administration of B, W and OA in rats. The resulted increased systemic exposure of OAG indicated that the co-administration might lead to the enhancement of bioavailability for the studied flavones in the form of glucuronides. / Li, Chenrui. / Adviser: Zuo Zhong. / Source: Dissertation Abstracts International, Volume: 73-03, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 201-236). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
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Extractability Profiling and Antioxidant Activity of Flavonoids in Sorghum Grain and Non-grain MaterialsNjongmeta, Nenge Lynda A. 2009 May 1900 (has links)
Grains, leaves, sheaths, glumes and stalks of sorghum varieties were
analyzed for total phenols, condensed tannins, flavan-4-ols, anthocyanins and in
vitro antioxidant activity. Black sorghum bran was used to evaluate the
effectiveness of organic acids and enzymes on extractability of phenols.
Flavonoid profiles of grains and non-grain tissues were determined and
characterized using HPLC-PDA and HPLC-ESI-MSn.
The presence of a pigmented testa and spreader genes (B1B2S) is a
predictor for polymeric flavonoids (tannins) but not for simple phenols such as
flavan-4-ols, 3-deoxyanthocyanins, flavones and flavanones. Simple flavonoids
increased antioxidant capacity of sorghum, and were present in all sorghum
except for the white pericarp sorghums that did not have flavanones. The "red
turning into black" gene increased phenols in Type I sorghum.
The leaves, sheath and glumes of sorghum had higher levels of phenols (78-600 times more), with in vitro antioxidant properties than commonly seen in
grains. Pigmentation of plant components increased levels of 3-
deoxyanthocyanins but not flavones nor flavanones. The leaves of biomass
sorghum, Collier variety, had 3.4 times more 3-deoxyanthocyanins than the
leaves of Tx430 Black x Sumac which had the highest levels (1810 ?g/g) of 3-
deoxyanthocyanins among the leaves.
The use of 1% HCl/ethanol provides a possible food grade substitute
solvent for 1%HCl/methanol in the extraction of phenolic compounds from
sorghum. All enzymes evaluated broke down bran particles forming a gel-like
material which had increased phenols and antioxidant activities but not 3-
deoxyanthocyanins as revealed by HPLC analysis. Microscopy examination
showed the gel matrix rich in fiber and can possibly be used for nutraceutical
applications. Careful understanding of enzyme activities is necessary for
effective extraction of 3-deoxyanthocyanins from sorghum.
Sorghum leaves, sheaths and glumes are excellent sources of bioactive
compounds, up to 600 times more than the grains of some varieties. Sorghum
with the "red turning to black genes" is a potential source of 3-
deoxyanthocyanins and flavan-4-ols. With the trend towards sorghum as
biomass for ethanol production, plant breeders must select special traits aimed
at developing enhanced desired functionality such as antioxidant potential and
other healthy attributes with application in food, pharmaceutical/nutraceutical
and cosmetic industries.
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Flavonoides de zornia brasiliensis e atividade antinociceptiva da 7-metoxiflavonaSilva, Anne Dayse Soares da 30 January 2013 (has links)
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Previous issue date: 2013-01-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The genus Zornia has about 75 species worldwide, with 41 representatives in America, 16 in Africa, 13 in Asia-Oceania and 7 (MOHLENDROCK 1961), is the second most numerous representative of clade Adesmia. Occurs in Brazil from the Amazon region to the "pampas" in Rio Grande do Sul Zornia brasiliensis species is popularly known as "urinaria", "urinana" and "carrapicho" is reported by its use in folk medicine as a diuretic. It occurs in several states in Brazil, being abundant in northeastern Brazil occurring in the states of Alagoas, Bahia, Ceará, Pernambuco, Rio Grande do Norte and Paraiba. Here we describe the isolation and structural elucidation of flavonoids, chalcones and Pterocarpans aerial parts of Zornia brasiliensis. For this the plant material after drying and pulverization was subjected to extraction processes, partition and chromatography for isolation of the chemical constituents. The same chemical structure was determined by spectroscopic methods IR, Mass Spectrometry and Nuclear Magnetic Resonance 1H and 13C and uni-dimensional as well as comparisons with literature. Phases of dichloromethane and ethyl acetate afforded three of five compounds flavones: 7-methoxyflavone, 5-hydroxy-7-methoxyflavone and 5,7-dimethoxyflavone, a chalcone 2 ', 4'-dihidroxichalcona pterocarpan and a 3 - hydroxy-9-metoxipterocarpano, all isolated for the first time in the genre. Furthermore, this study evaluated the antinociceptive activity of 7-methoxyflavone isolated in this study. Thus, the results contributed to the expansion of knowledge of gender Zornia chemotaxonomic and antinociceptive activity of a flavone, so far not. / O gênero Zornia possui cerca de 75 espécies no mundo, com 41 representantes na América, 16 na África, 13 na Oceania e 7 na Ásia (MOHLENDROCK 1961), é o segundo representante mais numeroso do clado Adesmia. No Brasil ocorre desde a região amazônica até os pampas no Rio Grande do Sul. A espécie Zornia brasiliensis é conhecida popularmente como urinária , urinana e carrapicho é relatada por sua utilização na medicina popular como diurética. Ocorre em vários estados do Brasil, sendo abundante no Nordeste do Brasil ocorrendo nos estados de Alagoas, Bahia, Ceará, Pernambuco, Rio Grande do Norte e Paraíba. Neste trabalho descrevemos o isolamento e elucidação estrutural de flavonoides, chalconas e pterocarpanos das partes aéreas de Zornia brasiliensis. Para isso o material vegetal, após secagem e pulverização, foi submetido a processos de extração, partição e cromatografia para isolamentos dos constituintes químicos. A estrutura química dos mesmos foi determinada pelos métodos espectroscópicos de Infravermelho, Espectrometria de Massas e Ressonância Magnética Nuclear de 1H e 13C uni e bidimensionais bem como por comparações com modelos da literatura. Das fases diclorometano e acetato de etila obtiveram-se cinco compostos sendo três flavonas: 7-metoxiflavona, 5-hidroxi-7-metoxiflavona e 5,7-dimetoxiflavona; uma chalcona a 2 ,4 -dihidroxichalcona e um pterocarpano o 3-hidroxi-9-metoxipterocarpano, todas isoladas pela primeira vez no gênero. Além disto, este trabalho avaliou a atividade antinociceptiva da 7-metoxiflavona isolada no presente trabalho. Desta forma, os resultados obtidos contribuíram para a ampliação do conhecimento quimiotaxonômico do gênero Zornia e da atividade antinociceptiva de uma flavona até então não estudada.
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Estudo fitoquÃmico de Stachytarpheta sessilis Moldenk / FitoquÃmico study of Stachytarpheta sessilis MoldenkRicardo Josà Pereira JÃnior 28 November 2008 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Este trabalho relata o estudo da composiÃÃo quÃmica nÃo-volÃtil de Stachytarpheta sessilis (Verbenaceae), coletada no municÃpio de Quixadà â CE, a partir da investigaÃÃo de extratos de raÃzes, talos e folhas desta espÃcie. Os extratos etanÃlicos dos talos (SSTE) e folhas (SSFE) de S. sessilis foram submetidos, separadamente, à partiÃÃo lÃquido-lÃquido com hexano, diclorometano e acetato de etila. A fraÃÃo diclorometano dos talos (SSTE-D) foi submetida a sucessivas cromatografias, resultando no isolamento da flavona crisoeriol e triterpeno pentacÃclico do tipo ursano Ãcido ursÃlico. Sucessivas cromatografias da fraÃÃo acetato de etila (SSTE-A) levaram ao isolamento do esterÃide stigmasterol na sua forma glicosilada e da flavona luteolina. O tratamento cromatogrÃfico da fraÃÃo diclorometano das folhas (SSFE-D) levou a obtenÃÃo da mistura de flavonas crisoeriol e apigenina. Sucessivas cromatografias a partir do extrato hexÃnico das talos (SSTH) permitiram a obtenÃÃo da mistura dos triterpenos pentacÃclicos do tipo ursano α e β-Amirina. A caracterizaÃÃo estrutural das substÃncias isoladas foi possÃvel atravÃs de anÃlise espectroscÃpica, utilizando-se as tÃcnicas de RMN uni e bidimensionais, Espectrometria de Massa e Infravermelho / This work outlines the study of non-volatile chemical composition of Stachytarpheta sessilis, collected in Chorozinho â CE, Brazil, through the investigation of roots, aerial parts and leaves extracts. Ethanol extracts of aerial parts and leaves of S. sessilis were submitted to liquid-liquid partition with hexane, dichloromethane (CH2Cl2) and ethyl acetate (EtOAc). The CH2Cl2 fraction of aerial parts was submitted to successive chromatography and the chrysoeriol flavone and the pentacyclic ursane triterpene ursolic acid were obtained. Successive chromatography of the EtOAc fraction yielded the isolation of glycosyl stigmasterol and luteolin flavone. Chromatographic treatment of the CH2Cl2 fraction from leaves yielded the isolation of a mixture of chrysoeriol and apigenin flavones. Successive chromatography from the hexane extract of aerial parts yielded the isolation of pentacyclic triterpene α and β amyrine as a mixture. The structural characterization of the isolated compounds was possible by spectroscopic analysis, using NMR uni and bidimensional, mass spectrometry and infrared techniques
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CLONING OF KNOWN AND NOVEL CYTOCHROME P450S IN SCUTELLARIA BAICALENISBrundage, Meghan Elizabeth 11 October 2001 (has links)
No description available.
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Effects of enzymatic and thermal processing on flavones, the effects of flavones on inflammatory mediators in vitro, and the absorption of flavones in vivoHostetler, Gregory 20 October 2011 (has links)
No description available.
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Flavinoides : identificação de fontes brasileiras e investigação dos fatores responsaveis pelas variações na composição / Flavonoids : identification of brazilian food sources and investigation of factors responsible for compositional variationHuber, Lisia Senger 18 May 2007 (has links)
Orientador: Delia B. Rodriguez-Amaya / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-10T05:46:01Z (GMT). No. of bitstreams: 1
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Previous issue date: 2007 / Resumo: Devido a crescente importância atribuída aos flavonóides nos últimos anos, decorrente de suas ações relacionadas à prevenção de doenças degenerativas, e aliada à carência de dados destes compostos em alimentos brasileiros, este estudo teve como objetivo determinar os teores de flavonóis e flavonas em alimentos consumidos no Brasil e avaliar alguns fatores que influenciam seus níveis nestes alimentos. Uma revisão bibliográfica é apresentada no Capítulo 1, na qual são descritos os principais efeitos benéficos à saúde, aspectos analíticos e fatores que influenciam os teores de flavonóides em alimentos. Estes compostos com ação benéfica à saúde, atuam como antioxidantes, inibidores da proliferação celular, antiestrogênicos e mediadores intracelulares, exercendo proteção principalmente contra câncer e doenças cardiovasculares. A determinação desses compostos normalmente é feita utilizando-se cromatografia líquida de alta eficiência com detector de arranjo de diodos. Os níveis de flavonóides em alimentos podem ser influenciados por vários fatores, como estação do ano, preparo e processamento de alimentos. O Capítulo 2 descreve o desenvolvimento e validação da metodologia analítica para determinação de flavonóis e flavonas em hortaliças. Utilizando-se Delineamento Composto Central Rotacional, obtiveram-se as melhores condições para extração e hidrólise dos flavonóides encontrados na natureza na forma glicosídica, a suas respectivas agliconas. Essas condições foram: 1,0M de HCl por 6 horas para espinafre e couve, 1,6M de HCl por 5 horas para rúcula, 1,2M de HCl por 2 horas para alface, 1,7M de HCl por 4,3 horas para salsa e 0,8M de HCl por 2,5 horas para cebola. As condições cromatográficas utilizadas foram coluna Nova-Pak C18 (4ìm, 3,9x150mm), e fase móvel constituída de metanol e água, acidificados com 0,3% de ácido fórmico, em gradiente linear. Utilizando a metodologia analítica validada no Capítulo 2, no Capítulo 3 foram identificados e quantificados os flavonóides de alface lisa (6,73-9,77'g/g de quercetina), alface crespa (7,18-30,8'g/g de quercetina), cebola branca (323-362'g/g de quercetina), cebola roxa (390-423'g/g de quercetina), couve (256-399'g/g de quercetina e 333-339'g/g de kaempferol), espinafre (52,8-62,3'g/g de quercetina e 145-170'g/g de kaempferol), rúcula (137-143'g/g de quercetina e 402-501'g/g de kaempferol) e salsa (1521-1636'g/g de apigenina). Também foi avaliado o efeito sazonal nos teores destes compostos, sendo que estes tenderam a ser maiores no verão que no inverno, embora as diferenças não tenham sido estatisticamente significativas. No Capítulo 4, foram determinados os teores de flavonóides em sucos prontos para o consumo, sucos concentrados e polpas de caju, acerola e pitanga, e em amostras de cebola e salsa desidratadas. Os resultados indicaram perdas de flavonóides durante o processamento destes alimentos. Os teores nas amostras processadas foram nitidamente menores aos obtidos previamente nas amostras in natura. Os derivados de frutas apresentaram teores decrescentes na seguinte ordem: polpas, suco concentrado, suco pronto para consumo. Os teores de quercetina nas amostras de cebola desidratada foram bastante variados, indicando diferenças de variedades utilizadas como matéria-prima ou nas condições de processamento empregadas. Os resultados sugerem que estudos de monitoramento das perdas de flavonóides, da matéria-prima ao produto final, são altamente requeridos. O comportamento de flavonóis em couve, espinafre e rúcula minimamente processados, estocados em atmosfera modificada, em diferentes temperaturas, na presença e ausência de luz, foi avaliado e discutido no Capítulo 5. A qualidade sensorial dessas amostras também foi avaliada, para verificar a vida-de-prateleira. No geral, a vida útil foi negativamente influenciada pelo aumento na temperatura de estocagem na presença de luz. Não ocorreram perdas pronunciadas nos teores destes compostos durante a estocagem das três folhas minimamente processadas, podendo inclusive aumentar em certos períodos do armazenamento / Abstract: Had the increasing importance attributed to the flavonóides in the last years, decurrent of its action related to the prevention of degenerative illnesses, and allied to the lack of data of these composites in Brazilian foods, this study it had as objective to determine texts of flavonóis and flavonas in foods consumed in Brazil and to evaluate some factors that influence its levels in these foods. A bibliographical revision is presented in Chapter 1, in which the main beneficial effect to the health, analytical aspects and factors are described that influence texts of flavonóides in foods. These composites with beneficial action to the health, act as antirust, inhibiting of the proliferation cellular, antiestrogênicos and mediating intracellular, exerting protection mainly against cardiovascular cancer and illnesses. The determination of these composites normally is made using liquid chromatography of high efficiency with detector of arrangement of diodes. The levels of flavonóides in foods can be influenced by some factors, as station of the year, preparation and processing of foods. Chapter 2 describes the development and validation of the analytical methodology for determination of flavonóis and flavonas in hortaliças. Using Rotational Central Composed Delineation, the best conditions for extration and hydrolysis of the flavonóides found in the nature in the glicosídica form, its respective agliconas had been gotten. These conditions had been: 1,0M of HCl for 6 hours for spinach and borecole, 1,6M of HCl for 5 hours for rúcula, 1,2M of HCl for 2 hours for lettuce, 1,7M of HCl for 4,3 hours for parsley and 0,8M of HCl for 2,5 hours for onion. The used chromatographic conditions had been column Nova-Pak C18 (4ìm, 3,9x150mm), and mobile phase consisting of methanol and water, acidified with 0,3% of acid fórmico, in linear gradient. Using the validated analytical methodology in Chapter 2, in Chapter 3 they had been identified and quantified the flavonóides of smooth lettuce (6,73-9,77'g/g of quercetina), lettuce crespa (7,18-30,8'g/g of quercetina), white onion (323-362'g/g of quercetina), purple onion (390-423'g/g of quercetina), borecole (256-399'g/g of quercetina and 333-339'g/g of kaempferol), spinach (52,8-62,3'g/g of quercetina and 145-170'g/g of kaempferol), rúcula (137-143'g/g of quercetina and 402-501'g/g of kaempferol) and parsley (1521-1636'g/g of apigenina). Also the sazonal effect in texts of these composites was evaluated, being that these had tended to be bigger in the summer that in the winter, the differences have even so not been estatisticamente significant. In Chapter 4, the texts of flavonóides in ready juices for the consumption, intent juices and cashew pulps, acerola and pitanga had been determined, and in samples of dehydrated onion and parsley. The results had indicated losses of flavonóides during the processing of these foods. The texts in the processed samples had been nitidamente lesser to gotten previously in the samples in natura. The derivatives of fruits had presented decreasing texts in the following order: pulps, concentrated juice, ready juice for consumption. The texts of quercetina in the samples of dehydrated onion sufficiently had been varied, indicating differences of used varieties as raw material or in the employed conditions of processing. The results suggest that studies of monitoramento of the losses of flavonóides, of the raw material to the end item, highly are required. The behavior of flavonóis in borecole, spinach and rúcula minimamente processings, storaged in modified atmosphere, in different temperatures, na.presença and absence of light, was evaluated and argued in Chapter 5. The sensorial quality of these samples also was evaluated, to verify the life-of-shelf. In the generality, the useful life negative was influenced by the increase in the temperature of stockage na.presença of light. Sharp losses in texts of these composites had not occurred during the stockage of three minimamente processed leves, also being able to increase in certain periods of the storage / Doutorado / Doutor em Ciência de Alimentos
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Citrus Fruits Quality Monitoring During Growth and Storage Period Using Fluorescence Spectroscopy / 蛍光分光法を用いた生育中および貯蔵中カンキツ果実の品質モニタリングMuharfiza 26 November 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第21428号 / 農博第2306号 / 学位論文||H30||N5156(農学部図書室) / 京都大学大学院農学研究科地域環境科学専攻 / (主査)教授 近藤 直, 准教授 小川 雄一, 教授 飯田 訓久 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM
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Methoxylated but not hydroxylated flavones elicit significant activity against Parp-1-mediated cell death (Parthanatos)Zhang, Jingwen, Marsh, J.R., Tait, A., Iqbal, M.M., Pritchard, C.J., Ma, A., Shang, Lijun, Fatokun, Amos A. 08 1900 (has links)
No / Flavonoids, of which flavones are a sub-group, are plant secondary metabolites found in a variety of natural food sources (e.g., vegetables) and wines. They elicit beneficial roles in health and disease through their antioxidant activity, but some of them have also now been found to exert specific effects on cell signalling.
We recently showed that methoxylation of the flavone structure at the 4ʹ position, or additionally at the 3ʹ position, to produce 4ʹ-methoxyflavone (4MF) and 3ʹ,4ʹ-dimethoxyflavone (DMF), respectively, significantly enhanced activity against the cell death (“parthanatos”) mediated by poly (ADP-ribose) polymerase (PARP). We report here our attempt to correlate the antioxidant and parthanatos-inhibitory activities of these methoxylated flavones with those of the hydroxylated flavonoids.
Cultures of HeLa and HaCaT cells were exposed to MNNG (50µM, up to 25min), which induces parthanatos, and the oxidant hydrogen peroxide (100µM – 2mM, up to 24h). The effects (up to 20µM) of the methoxylated flavones 4MF and DMF, the hydroxylated flavone luteolin (LN), and the non-flavone flavonoids quercetin (QE), naringin (NG) and epigallocatechin gallate (EGCG) on the reduction in viability (indicative of cell death) and morphological changes induced by MNNG or peroxide were then investigated. Both alamar blue and MTT assays were used to quantify viability.
MNNG induced significant reduction in cell viability, which was not affected by the pan-caspase inhibitor Z-VAD-fmk but significantly blocked by DPQ, a PARP-1 inhibitor, consistent with the biochemical profile of parthanatos. Hydrogen peroxide also elicited a significant decrease in cell viability, with partial or no protection afforded by either Z-VAD-fmk or DPQ (dependent on peroxide concentration and treatment duration). 4MF and DMF demonstrated significant protection against MNNG-induced cell death but LN, QE, NG and EGCG showed little or no protection. On the other hand, 4MF and DMF elicited mostly negligible effects against hydrogen peroxide, whereas LN, QE, NG and EGCG elicited various levels of protection against it.
We conclude that methoxylation at the 4ʹ or 3ʹ, 4ʹ positions of flavones favours anti-parthanatos but not antioxidant activity, whereas hydroxylation enhances antioxidant but not anti-parthanatos activity. / Abstract of conference paper.
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Estudo Químico e Avaliação da Toxicidade e das Propriedades Antioxidante e Anticolinesterásica de Lindackeria paraensis Kuhlm. (Flacourtiaceae). / Chemical constituints the evaluation of toxidade against Artemia salina seach the of properties antioxidant, inibition of acetylcholinesterase the Lindackeria paraensis Kuhlm. (Flacourtiaceae).Ribeiro, Edmilson Pinto 06 November 2009 (has links)
This work describes the isolation of some chemical constituents besides the evaluation
of toxicity against Artemia salina Leach, total phenolic content, using Folin-Ciocalteu reagent,
inhibition of acetylcholinesterase and antioxidant (DPPH) activities of extracts of leaves of
Lindackeria paraensis Kulhm (Flacourtiaceae). In the antioxidant assays, some of the extracts
and chromatographic fractions tested showed high total phenolic content, when compared to
positive controls used (ascorbic acid, α-tocopherol and BHT) free radicals scavenger. In the
anticholinesterasic assays, some these extracts were effective to inhibit the enzyme. On the
other hand, in the toxicity assay against Artemia salina, among samples tested, only three
were non toxic (LC50 upper to 1000 mg/mL) and seven showed high toxicity (LC50 under to
500 mg/mL), suggesting that this species must be evaluated for other activities, such as
insecticidal, pesticide, cercaricidal and others that dependent of citotoxicity. Phytochemical
study with some these active extracts conduced to the isolation of two pentacyclic triterpenes
(fridelin and fridelinol) and four flavones (5-Hydroxy-7,4 -dimethoxyflavone, 5,4 -Dihydroxy-
7-methoxy-flavone, 5,7,4 -Trihydroxy-3 -methoxyflavone, and 5,4 -Dihydroxy-7,3 -
dimethoxyflavone). All isolated compounds were identified on the basis of the NMR spectral
data and by comparison with literature data and are being described for the first time in the
genus Lindackeria. The flavones identified as 5,7,4 -trihydroxy-3 -methoxyflavone, 5-
hydroxy-7,4 -dimethoxy-flavone and 5,4 -Dihydroxy-7-methoxyflavone free scavenging
radicals against DPPH and 5,4 -dihydroxy-7-methoxyflavone inhibited the action of
anticholinesterase enzyme. / O presente trabalho descreve o isolamento de alguns constituintes químicos, a
avaliação da toxicidade frente à Artemia salina Leach, o conteúdo de fenóis totais (reagente
Folin-Ciocalteu) e as atividades anticolinesterásica e antioxidante, utilizando o DPPH, de
extratos e frações das folhas de Lindackeria paraensis Kuhlm (Flacourtiaceae). Nos ensaios
antioxidantes, alguns dos extratos e frações testados forneceram altos teores de fenóis totais e,
quando comparados com os padrões positivos utilizados (ácido ascórbico, α-tocoferol e BHT),
seqüestraram radicais e DPPH. Alguns desses extratos foram eficazes em inibir o efeito da
enzima acetilcolinesterase. Nos ensaios de toxicidade frente à Artemia salina, dentre as
amostras que foram avaliadas, somente três foram atóxicas (CL50 superior a 1000 mg/mL) e
sete mostraram alta toxicidade (CL50 inferior a 500 mg/mL), sugerindo que esta espécie possui
outras atividades biológicas, tais como inseticida, pesticida, cercaricida e outras que
dependam de citotoxicidade. O estudo fitoquímico efetuado com alguns dos extratos ativos
conduziu ao isolamento de dois triterpenos pentacíclicos (Fridelina e Fridelinol) além de
quatro flavonas (5-Hidroxi-7,4 -dimetoxiflavona, 5,4 -Dihidroxi-7-metoxyflavona, 5,7,4 -
Trihidroxi-3 -metoxi-flavona e 5,4 -Dihidroxi-7,3 -dimetoxiflavona). Estas substâncias
tiveram suas estruturas identificadas com base na análise dos dados de RMN e pela
comparação com dados da literatura e todas estão sendo relatadas pela primeira vez no gênero
Lindackeria. As flavonas identificadas como 5,7,4 -trihidroxi-3 -metoxiflavona, 5-Hidroxi-
7,4 -dimetoxiflavona e 5,4 -Dihidroxi-7-metoxi-flavona frente ao DPPH sequestraram o
radical e nos ensaios anticolinesterásicos, somente a flavona identificada como 5,4 -
Dihidroxi-7-metoxiflavona inibiu a ação desta enzima.
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