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1

Recalde, Gil Maria Angélica. "Potencial inibitório in vitro de biflavonoides de Garcinia gardneriana : um estudo sobre monoamina oxidades e CYP19 (aromatase)." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2015. http://hdl.handle.net/10183/149485.

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The plant Garcinia gardneriana (Planch. & Triana) Zappi, popularly known in Brazil as "bacupari" has traditionally been used for various types of inflammatory diseases and the evaluation of their chemical composition, mainly of leaves, has resulted in biflavonoids as major compounds. These phenolic compounds have shown anti-inflammatory activity validating the popular use of the plant. In this work was isolated from dried branches of Garcinia gardneriana the biflavonoids: morelloflavone, that is an naringenin covalently linked to luteolin, Gb-2a which is an naringenin linked to eriodictyol and Gb-2a- 7-O-glucose. These compounds have been previously evaluated in various activities such as anti-inflammatory and anti-antioxidants but there is no report of its activity as enzymatic inhibitors. However, the monomers that form it, have been evaluated in the inhibition of aromatase and antidepressant activity with positive outcome, which commonly are used MAO-A inhibitors. In the isolation process were also founded terpenoid compounds as lupeol and friedelin The isolated and purified biflavonoids were used to evaluate enzyme inhibition "in vitro" in monoamine oxidases (MAO-A MAO-B) and aromatase. The compounds showed a positive response even of IC50 5,47 μM and 1,35 μM for MAO-A inhibition of and aromatase enzyme respectively; discovering a way for a new proposal to link both enzymes for treatment of hormone-dependent cancers and anxiety and depression disorders.
La planta Garcinia gardneriana (Planch. & Triana) Zappi, popularmente conocida en Brasil como "bacupari" ha sido tradicionalmente usada para varios tipos de enfermedades inflamatorias y la evaluación de su composición química, principalmente de las hojas, ha resultado en biflavonoides como compuestos mayoritarios. Estos compuestos fenólicos han demostrado actividad anti-inflamatória validando el uso popular de la planta. En este trabajo se asilaron a partir de tallos secos de la Garcinia gardneriana los biflavonoides: moreloflavona, que consiste en una naringenina unida covalentemente a luteolina, Gb-2a que es un compuesto que consiste en una naringenina unida a un eriodictyol y Gb-2a-7-O-glucose. Estos compuestos ya han sido previamente evaluados en diversas actividades como anti inflamatorios y anti antioxidantes pero no se tiene reporte de su actividad como inhibidores enzimáticos. Sin embargo, los monomeros que los conforman han sido evaluados en la inhibición de la aromatasa y con resultados positivos como en la actividad antidepresiva, para la cual comúnmente son usados los inibidores de MAO-A. En el proceso de aislamiento también fueron encontrados compuestos terpenoides como lupeol y friedelina. Los biflavonoides aislados y purificados se usaron para evaluar la inhibición enzimática “in vitro” en monoaminooxidasas (MAO-A, MAO-B) y aromatasa. Los compuestos presentaron una respuesta positiva calculada con IC50 de hasta 5,47 μM y 1,35 μM para la inhibición de las enzimas MAO-A y aromatasa respectivamente, abriendo el camino a una nueva propuesta de relacionar estas dos enzimas para tratamiento de cánceres hormonodependientes y transtornos de ansiedad y depresión.
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2

Oliveira, José Cândido Selva de. "Isolamento de constituintes e síntese de flavonoides encontrados em Poincianella pyramidalis (Fabaceae) e análise fitoquímica de Theobroma cacao (Malvaceae)." Instituto de Química, 2014. http://repositorio.ufba.br/ri/handle/ri/16127.

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CNPq e CAPES
Os extratos MeOH de Poincinella pyramidalis (caatingueira), obtidas da casca da raiz (PPCR) e das flores (PPF), bem como, as frações orgânicas obtidas por partição, foram submetidas a testes de atividade citotóxica, antioxidante e anticolinesterásica. O teste citotóxico contra Artemia salina revelou atividade moderada para fase AcOEt em PPCR. Assim como, a fase AcOEt de PPCR apresentou 75% de inibição no teste anticolinesterásico. Para a atividade antioxidante, as fase AcOEt e BuOH de PPF foi a mais ativa, sendo atribuída a presença de galato de metila (PPF3). Por meio de processos cromatográficos foi possível isolar da fase DCM de PPF as substâncias PPF1 (alcoóis graxos), PPF2a-b (β–sitosterol/estigmasterol), PPF3 (galato de metila) e PPF4 (α e β–amirina). Além dessas, foram isoladas da fase hexano de PPCR ésteres metílicos (PPCR1) e o biflavonoide 5,7-dihidroxi-4´-metoxiflavona-6α-2´´´,4´´´-dihidroxi-4´´- metoxidihidrochalcona (PPCR3). Da fase hidroMeOH de PPCR foram isoladas as substâncias PPCR2 (ácido 3,3´-dimetoxi-4-hidroxielagico-4´-β-D-xilopiranosideo) e outro biflavonoide PPCR4 (5-hidroxi-7,4´-dimetoxiflavona-3α-2´´´-hidroxi-4´´´,4´´- dimetoxidihidrochalcona). Sendo PPCR3 e PPCR4 inéditas na literatura. O extrato hexano de Theobroma cacao (cacau) obtido das sementes (STC) foi analisado por RMN e revelou presença de triacilglicerideos. A otimização e fracionamento do extrato MeOH de T. cacao utilizando CCC levou ao isolamento simultâneo de teobromina (2), teofilina (3) e cafeína (4), fase móvel hexano:AcOEt (2:3) e estacionária MeOH:H2O (1:1). Um método analítico foi desenvolvido empregando HPLC/DAD com coluna fase reversa C-18 para a quantificação de 2, 3 e 4 nos extrativos em fase ácida/básica e nas frações STC6-22 e STC23-67 obtidas por CCC. Assim, os teores de 2 e 4 para no extrato MeOH de T. cacao e frações obtidas por CCC foram determinados. A teofilina (3) detectada e quantificada na fração STC6-22 em baixa concentração (0,78 mg/g) em relação a 2 e 4. A apigenina (6) foi sintetizada utilizando dois métodos distintos (“A” e “B”). O metodo “B” apresentou rendimento de 74% em uma única etapa. A síntese de derivados O-metilados forneceu bons rendimentos (> 90%). As substâncias isoladas/sintetizadas foram submetidas à atividade anticolinesterasica do qual, são inativas. As mesmas foram elucidadas a partir de dados de IV, UV, EM, α[D], RMN de 1H e 13C (BB e APT), RMN de correlação (HMQC, HSQC e HMBC).
The MeOH extracts from Poincinella pyramidalis (caatingueira), obtained of bark root (PPCR) and flowers (PPF), as well the organic fractions obtained by partition, have been tested for cytotoxicity, antioxidant and anticholinesterasic activity. The cytotoxic test against Artemia salina showed moderate activity for AcOEt phase in PPCR. Well the EtOAc phase of PPCR showed 75% inhibition on anticholinesterasic test. For the antioxidant activity, the EtOAc and BuOH phase of PPF was the most active, being attributed to the presence of methyl gallate (PPF3). For chromatographic process was possible to isolate the DCM phase of PPF the substances PPF1 (fatty alcohols), PPF2a- b (β–sitosterol/stigmasterol), PPF3 (methyl galate) and PPF4 (α- and β–amirin). Besides these, were isolated from the hexane phase PPCR methyl esters (PPCR1) and the biflavonoid 5,7-dihidroxy-4´-methoxyflavone-6α-2´´´,4´´´-dihidroxy-4´´-methoxy dihidrochalcone (PPCR3). The HidroMeOH phase of PPCR were the isolated substances PPCR2 (3,3´-dimethoxi-4-hidroxyellagicacid-4´-β-D-xylopiranoside) and other biflavonoid PPCR4 (5-hidroxy-7,4´-dimethoxyflavone-3α-2´´´-hidroxy-4´´´,4´´- dimethoxydihidrochalcone). Being PPCR3 and PPCR4 unpublished in literature. Hexane extract of Theobroma cacao (cacau) obtained from the seeds (STC) was analyzed by NMR and revealed the presence of triacylglycerides. The optimization and fractionation of MeOH extract of T. cacao using CCC led to the simultaneous isolation of theobromine (2) Theophylline (3) and caffeine (4), mobile phase hexane:EtOAc (2:3) and stationary MeOH:H2O (1:1). An analytical method was developed employing HPLC/DAD with reverse phase column C-18 for the measurement of 2, 3 and 4 in the extractives acid/base phase and the STC6-22 and STC23-67 fractions obtained by CCC. So, the levels of 2 and 4 for the MeOH extract of T. cacao and fractions obtained by CCC were determined. Theophylline (3) detected and quantified in the fraction STC6-22 low concentration (0.78 mg/g) in relation the 2 and 4. Apigenin (6) was synthesized using two different methods ("A" and "B"). The method "B" had a yield of 74% in one step. The synthesis of O-methylated derivatives provided good yields (> 90%). The isolated/synthesized substances were submitted to anticholinesterasic activity which are inactive. The same were elucidated from data of IR, UV, MS, α[D], 1H NMR and 13C NMR (BB and APT) NMR correlation (HMQC, HSQC and HMBC).
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3

Santos, Elis?ngela. "Identifica??o de inibidores oriundos de fontes naturais para o modelo do receptor atpase-ca+2 do Plasmodium falciparum (PfATP6)." Universidade Estadual de Feira de Santana, 2014. http://localhost:8080/tede/handle/tede/105.

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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES
Malaria is considered a non-contagious chronic evolution with episodic manifestations of acute character infectious disease, which afflicts millions of people in tropical and subtropical areas of the world. Vegetables represent a source of active molecules for various diseases, including malaria. Through phytochemical procedures, one can study the secondary metabolism of these plants where they hope to find new sources of treatment for malaria. The present study had as main objective to identify molecules derived from natural sources can inhibit the ATPase-Ca 2 + protein of Plasmodium falciparum (PfATP6). The molecular target was the model PfATP6 receiver, obtained by comparative modeling. Was performed using the program AutoDock Vina 1.1.2. screening in databases with the aim of selecting the 10 most promising ligands, with determination of the energies of affinity. Subsequently, tests with hydromethanolic and chloroform extracts of the species of Tul Cenostigma macrophyllum were performed. The patterns of agatisflavona and amentoflavone biflavonoids were analyzed by High Performance Liquid Chromatography for Detection Arrangement Diodes (HPLC-DAD) to identify the presence of these metabolites in the species. Validation of the chromatographic method took into account the parameters selectivity, linearity, precision, accuracy, limit of detection and limit of quantification. The results showed molecular next coupling energy variation among the 10 selected compounds (1 kcal / mol). With the results of the molecular coupling of the intermolecular interactions were studied and agatisflavona amentoflavone with PfATP6 receiver comparing them with the values obtained for thapsigargin. Since the energy values affinity the compounds amentoflavone -10.0 kcal / mol and agatisflavona -9.7 kcal / mol ortost?rico showed affinity for the receptor site of PfATP6, these interactions being supported by the nature of intermolecular interactions identified. By comparing the retention times and ultraviolet spectra (UV) of the standards and samples could be identified agatisflavona amentoflavone and biflavonoids the leaves and stem bark of C. macrophyllum. Quantification of agatisflavona biflavonoide ranged from 22.25 to 0.012 mg of agatisflavona / g dry plant and amentoflavone ranged from 20.63 to 0.02 mg of amentoflavone / g dry plant. The analysis of the parameters evaluated showed that the method was suitable for the analysis of agatisflavona and amentoflavone, performing in line with the specifications of the current legislation. It is noticed that the amentoflavone agatisflavona compounds and can act in PfATP6 receiver, directing further studies of interactions in biological target in perspective for malaria control. Thus, it is possible to suggest that there are natural compounds present in semiarid with possible antimalarial activity, wherein the molecular modeling tool associated with the phytochemical analysis can guide the identification of bioactive compounds, and therefore the development of new drugs.
A mal?ria ? considerada como uma doen?a infecciosa, n?o contagiosa de evolu??o cr?nica com manifesta??es epis?dicas de car?ter agudo, a qual aflige milh?es de pessoas nas zonas tropicais e subtropicais do globo. Os vegetais representam fonte de mol?culas ativas para diversas enfermidades, incluindo a mal?ria. Atrav?s de procedimentos fitoqu?micos, pode-se estudar o metabolismo secund?rio desses vegetais onde se esperam encontrar novas fontes de tratamento para a mal?ria. O presente estudo teve como objetivo geral identificar mol?culas oriundas de fontes naturais capazes de inibir a prote?na ATPase-Ca+2 do Plasmodium falciparum (PfATP6). O alvo molecular foi o modelo do receptor PfATP6, obtido por modelagem comparativa. Foi realizado atrav?s do programa AutoDock Vina 1.1.2. uma triagem em bancos de dados com o objetivo de selecionar os 10 ligantes mais promissores, com determina??o das energias de afinidade. Posteriormente, foram realizados testes com os extratos hidrometan?lico e clorof?rmico da esp?cie de Cenostigma macrophyllum Tul. Os padr?es dos biflavonoides agatisflavona e amentoflavona foram analisados por Cromatografia L?quida de Alta Efici?ncia por Detec??o de Arranjo de Diodos (CLAE-DAD) para identifica??o da presen?a destes metab?litos na esp?cie. A valida??o do m?todo cromatogr?fico levou em considera??o os par?metros seletividade, linearidade, precis?o, exatid?o, limite de detec??o e limite de quantifica??o. Os resultados de acoplamento molecular apresentaram varia??o energ?tica pr?xima entre os 10 compostos selecionados (1 kcal/mol). De posse dos resultados do acoplamento molecular foram estudadas as intera??es intermoleculares da agatisflavona e amentoflavona com o receptor PfATP6 comparando-os com os valores obtidos para a tapsigargina. Dado os valores de energia de afinidade, os compostos amentoflavona -10,0 Kcal/mol e agatisflavona -9,7 Kcal/mol apresentaram afinidade com o s?tio ortost?rico do receptor PfATP6, sendo essas intera??es sustentadas pela natureza das intera??es intermoleculares identificadas. Atrav?s da compara??o dos tempos de reten??o e espectros de Ultra Violeta (UV) dos padr?es e amostras foi poss?vel identificar os biflavonoides agatisflavona e amentoflavona nas folhas e casca do caule de C. macrophyllum. A quantifica??o do biflavonoide agatisflavona variou de 22,25 a 0,012 ?g de agatisflavona/g de planta seca e da amentoflavona variou de 20,63 a 0,02 ?g de amentoflavona/g de planta seca. A an?lise dos par?metros avaliados demonstrou que o m?todo foi adequado para a an?lise da agatisflavona e amentoflavona, apresentando-se em conson?ncia com as especifica??es da legisla??o vigente. Percebe-se que os compostos amentoflavona e agatisflavona podem atuar no receptor PfATP6, direcionando novos estudos de intera??es nesse alvo biol?gico na perspectiva de controle da mal?ria. Desta forma ? poss?vel sugerir que existem compostos naturais presente no semi?rido com poss?vel atividade antimal?rica, no qual a ferramenta da modelagem molecular associada ?s analises fitoqu?micas pode guiar na identifica??o de compostos bioativos e, por conseguinte no desenvolvimento de novos f?rmacos.
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4

Burgos, Rosilene Cristina Rossetto. "Detecção in silico, isolamento e caracterização estrutural dos constitutintes micromoleculares antimaláricos e antioxidantes em galhosmdemGarcina gardneriana (Clusiaceae) /." Araraquara, [s.n.], 2010. http://hdl.handle.net/11449/97014.

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Resumo: Este trabalho teve como principais objetivos a detecção, isolamento e elucidação estrutural dos constituintes micromoleculares presentes em folhas e galhos de Garcinia gardneriana, uma espécie da família Clusiaceae com poucos relatos na literatura sobre a sua composição fitoquímica. A detecção das moléculas foi realizada através de abordagens in silico com o estabelecimento de perfis cromatográficos e espectrométricos dos constituintes majoritários dos extratos brutos e frações. A comparação desses dados foi realizada através de dados existentes na literatura. A partir dessa metodologia foi possível detectar 11 triterpenos por GC-FID nos extratos e frações apolares: campesterol (1), estigmasterol (2), β-sitosterol (3), β- amirenona (4), α- amirina (5), β-amirina (6), lupenona (7), lupeol (8), acetato de β-amirina (9), acetato de α-amirina (10), friedelina (11) e mais 9 biflavonóides nos extratos e frações mais polares: xantochimusídeo (12), GB2 (13), fukugisídeo (14), GB 1a glicosilado (15), GB2a (16), morelloflavona (17), volkensiflavona (18), amentoflavona (19), podocarpusflavona (20) e uma benzofenona: 7-epiclusianona (21) através da técnica HPLC-DAD-ESI-MSHRMS. Quanto aos bioensaios in vitro realizados (inibição da polimerização do heme, redução do radical DPPH (antioxidante), inibidor da enzima acetilcolinesterase, tripanocida, citotóxico, antifúngico contra fitopatógenos e patógenos humanos) em todos os extratos e frações preparados, alguns resultados merecem destaque tais como a redução do radical DPPH com IC50 de 9,5, 7,4 e 7,5 μg/mL respectivamente para o extrato etanólico dos galhos, a fração acetato de etila dos galhos e folhas, a inibição da polimerização do heme com valores de 95,7, 98,6 e 68,0 %, de inibição para o extrato etanólico das folhas, e frações acetato de etila das folhas e galhos respectivamente
Abstract: This work had as main objective the detection, isolation and structural elucidation of the micromolecular constituents from leaves and twigs of Garcinia gardneriana, a Clusiaceae species with few literature reports regarding its phytochemical composition. The detection of molecules was performed by in silico detection with the establishment of chromatographic and spectroscopic profiles of the major constituents present in the crude extracts and fractions as well as comparison of data from database and literature reports. Based on this methodology we were able to detect 11 triterpenes by GC-FID in the extracts and nonpolar fractions: campesterol (1), stigmasterol (2), β-sitosterol (3), β-amirenone (4), α- amyrin (5), β-amyrin (6), lupenone (7), lupeol (8), β-amyrin acetate (9), α-amyrin acetate (10), friedelin (11) and more 9 biflavonoids from extracts and fractions polar: xanthochymuside (12) and GB2 (13), fukugiside (14), GB1 glycosylated (15), GB2a (16), morelloflavone (17), volkensiflavone (18), amentoflavone (19) , podocarpusflavone (20), 7-epiclusianone (21) by HPLC-DAD-ESI-MS-HRMS. As for the performed in vitro bioassays (inhibition of heme polymerization, reduction of the DPPH radical (antioxidant), inhibition of the enzyme acetylcholinesterase, trypanocidal, cytotoxic antifungal activity against plant pathogens and human pathogens) in all extracts and fractions prepared in this work, some results are worthy of mentioning such as the reduction of the DPPH radical with IC50 values of 9.5, 7.4 and 7.5 μg/mL respectively for the ethanol extract from twigs, the ethyl acetate fraction from the branches and leaves, as well as the inhibition of heme polymerization with values of 95.7, 98.6 and 68.0% from the ethanol extract from the leaves, and the ethyl acetate fractions leaves and branches
Orientador: Ian Castro Gamboa
Coorientador: Márcia Nasser Lopes
Banca: Mario Sergio Palma
Banca: Carlos Alexandre Carollo
Mestre
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5

Burgos, Rosilene Cristina Rossetto [UNESP]. "Detecção in silico, isolamento e caracterização estrutural dos constitutintes micromoleculares antimaláricos e antioxidantes em galhosmdemGarcina gardneriana (Clusiaceae)." Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/97014.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Este trabalho teve como principais objetivos a detecção, isolamento e elucidação estrutural dos constituintes micromoleculares presentes em folhas e galhos de Garcinia gardneriana, uma espécie da família Clusiaceae com poucos relatos na literatura sobre a sua composição fitoquímica. A detecção das moléculas foi realizada através de abordagens in silico com o estabelecimento de perfis cromatográficos e espectrométricos dos constituintes majoritários dos extratos brutos e frações. A comparação desses dados foi realizada através de dados existentes na literatura. A partir dessa metodologia foi possível detectar 11 triterpenos por GC-FID nos extratos e frações apolares: campesterol (1), estigmasterol (2), β-sitosterol (3), β- amirenona (4), α- amirina (5), β-amirina (6), lupenona (7), lupeol (8), acetato de β-amirina (9), acetato de α-amirina (10), friedelina (11) e mais 9 biflavonóides nos extratos e frações mais polares: xantochimusídeo (12), GB2 (13), fukugisídeo (14), GB 1a glicosilado (15), GB2a (16), morelloflavona (17), volkensiflavona (18), amentoflavona (19), podocarpusflavona (20) e uma benzofenona: 7-epiclusianona (21) através da técnica HPLC-DAD-ESI-MSHRMS. Quanto aos bioensaios in vitro realizados (inibição da polimerização do heme, redução do radical DPPH (antioxidante), inibidor da enzima acetilcolinesterase, tripanocida, citotóxico, antifúngico contra fitopatógenos e patógenos humanos) em todos os extratos e frações preparados, alguns resultados merecem destaque tais como a redução do radical DPPH com IC50 de 9,5, 7,4 e 7,5 μg/mL respectivamente para o extrato etanólico dos galhos, a fração acetato de etila dos galhos e folhas, a inibição da polimerização do heme com valores de 95,7, 98,6 e 68,0 %, de inibição para o extrato etanólico das folhas, e frações acetato de etila das folhas e galhos respectivamente
This work had as main objective the detection, isolation and structural elucidation of the micromolecular constituents from leaves and twigs of Garcinia gardneriana, a Clusiaceae species with few literature reports regarding its phytochemical composition. The detection of molecules was performed by in silico detection with the establishment of chromatographic and spectroscopic profiles of the major constituents present in the crude extracts and fractions as well as comparison of data from database and literature reports. Based on this methodology we were able to detect 11 triterpenes by GC-FID in the extracts and nonpolar fractions: campesterol (1), stigmasterol (2), β-sitosterol (3), β-amirenone (4), α- amyrin (5), β-amyrin (6), lupenone (7), lupeol (8), β-amyrin acetate (9), α-amyrin acetate (10), friedelin (11) and more 9 biflavonoids from extracts and fractions polar: xanthochymuside (12) and GB2 (13), fukugiside (14), GB1 glycosylated (15), GB2a (16), morelloflavone (17), volkensiflavone (18), amentoflavone (19) , podocarpusflavone (20), 7-epiclusianone (21) by HPLC-DAD-ESI-MS-HRMS. As for the performed in vitro bioassays (inhibition of heme polymerization, reduction of the DPPH radical (antioxidant), inhibition of the enzyme acetylcholinesterase, trypanocidal, cytotoxic antifungal activity against plant pathogens and human pathogens) in all extracts and fractions prepared in this work, some results are worthy of mentioning such as the reduction of the DPPH radical with IC50 values of 9.5, 7.4 and 7.5 μg/mL respectively for the ethanol extract from twigs, the ethyl acetate fraction from the branches and leaves, as well as the inhibition of heme polymerization with values of 95.7, 98.6 and 68.0% from the ethanol extract from the leaves, and the ethyl acetate fractions leaves and branches
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6

FERREIRA, Rafaela Oliveira. "Contribuição ao estudo químico e avaliação da atividade antioxidante dos frutos verdes de Clusia paralicola (Clusiaceae)." Universidade Federal Rural de Pernambuco, 2011. http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/6373.

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Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq
Clusia paralicola (Clusiaceae) occurrs in forests from northeastern Brazil, especially in the semi-arid and wet forests, is popularly known as pororoca. This work describes the chemical and antioxidant activity of the green fruits from Clusia paralicola G. Mariz Cunha and resulted in the isolation and identification of two biflavonoids (GB1-7"-Oglucoside and 3,8 '-binaringenin-7"-O-β-glucoside), a catechin (epicatechin), two steroids (β-sitosterol and stigmasterol), a phenylpropanoid (1,3,5-trimethoxy-2- propenilbenzen) and a triterpene (β-amyrin). The structures of isolated compounds were elucidated by analysis of NMR spectra of ¹H and ¹³C, including 2D and LC-ESI-MS The absolute stereochemistry of biflavonoids was determined by circular dichroism analysis and complete structural elucidation was performed to GB1-7-O-glucoside. To determine the total phenolic content was used Folin-Ciocalteu test and to evaluate the antioxidant potential were used DPPH, ABTS and the system β-carotene/ linoleic acid with the EtOH extract and hexane, EtOAc and MeOH/H2O fractions. Evaluation of antioxidant activity was also performed with mixtures of two biflavonoids. For the total phenolic content, antiradicalar activity (DPPH and ABTS) and antioxidant activity with the system β carotene/linoleic acid were more active the EtOH extract and EtOAc fraction. The EtOH extract and fractions tested showed correlation with the total phenolic content and activity antioxidant. With the exception of β-amyrin, previously identified in the latex of C. paralicola, all substances are being reported for the first time in this species. The absolute stereochemistry was determined as (2R, 3S, 2”R, 3”R)-GB1-7-O-glucoside and (2R, 3S, 2”R)-3.8'-binaringenina-7-O-glycoside. These biflavonoids are inedited in the Clusia genus.
Clusia paralicola (Clusiaceae) têm ocorrência nas florestas nordestinas, especialmente do semi-árido e dos brejos de altitude, é conhecida popularmente como pororoca. Este trabalho descreve o estudo químico e a avaliação da atividade antioxidante dos frutos verdes de Clusia paralicola. O estudo químico resultou no isolamento e identificação de dois biflavonóides (GB-1-7”-O-glicosídeo e 3,8”-binaringenina-7”-O-β-glicosídeo), uma catequina (epicatequina), dois esteróides (β-sitosterol e estigmasterol), um fenilpropanóide (1,3,5-trimetoxi-2-propenilbenzeno) e um triterpeno (β-amirina). As estruturas das substâncias isoladas foram elucidadas pelas análises dos espectros de RMN de ¹H e ¹³C, incluindo 2D e LC-ESI-MS. A estereoquímica absoluta dos biflavonoides foi determinada através da análise de dicroismo circular e a elucidação estrutural completa foi realizada com GB1-7-O-glicosídeo. Para a determinação do teor de fenólicos totais foi utilizado o reagente de Folin-Ciocalteu e para avaliar o potencial antioxidante foram realizados os ensaios com DPPH, ABTS e o sistema β- caroteno/ácido linoléico com o extrato EtOHe frações hexânica, AcOEt e MeOH/H2O. A avaliação da atividade antioxidante foi realizada também com a mistura dos biflavonoides. Para o teor de fenólicos totais, atividade antiradicalar (ABTS e DPPH) e atividade antioxidante com o sistema β-caroteno/ácido linoléico foram mais ativos o extrato EtOH e a fração AcOEt. O extrato EtOH e frações testadas apresentaram correlação com o teor de fenólicos totais e atividade antioxidante. Com exceção da β- amirina, previamente identificada no látex de C. paralicola, todas as substâncias estão sendo relatadas pela primeira vez nesta espécie. A esteroquímica absoluta foi determinada como sendo (2R, 3S, 2”R, 3”R)- GB1-7-O-glicosídeo e (2R, 3S, 2”R)-3,8”- binaringenina-7-O-glicosídeo. Estes biflavonóides são inéditos no gênero Clusia.
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7

Santos, Calila Teixeira. "Frutos de Schinus terebinthifolius Raddi: extra??o ativa, estudo fitoqu?mico e incorpora??o em filmes bioativos de pectina." Universidade Estadual de Feira de Santana, 2017. http://localhost:8080/tede/handle/tede/595.

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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES
The present study had as main objective to obtain bioactive extracts of the fruits of Schinus terebinthifolius Raddi (STF), with antioxidant and antimicrobial action, for incorporation in a bioactive package for foods, besides inhibition of acetylcholinesterase. The extraction process performed by focussed microwave (EAMF) and ultrasound (UAE). The comparison between extraction methods was monitored by the biological activities of these extracts. The results showed that for the yield there was no significant difference. For the EAMF assays, the best value of phenolic (5950 ? 1.4 mgGAE / g) and total flavonoids (1750 ? 3.2 mgEQ / g) was at the extraction time of 25 minutes at 51 ? C and with 75% ethanol. For the assays obtained by EAU, the best total phenolic content was (92.2 ? 0.8 mgGAE / g) in the EAU 10 test (extraction time of 30 minutes at 42 ? C and 50% ethanol) And flavonoids (67.72 ? 1.0 mgEQ / g) in the UAE 12 assay (extraction time of 17.5 minutes at 60 ? C and 50% ethanol). The best values for percent inhibition (% SRL) were 87.3% (EAMF 8) and 31.3% (UAE 12). Mass spectrometry analysis showed the presence of phenolic compounds and terpenes. In relation to the antimicrobial activity of extracts obtained by EAMF, the MIC for S. aureus was 0.5 mg / ml for E. coli 0.25 mg / ml, whereas the extract of EAU presented MIC of 0.5 mg / Ml for the two microorganisms analyzed. In the phytochemical study, it was possible to isolate 7 substances: agasthiflavone, tetrahydrorobustaflavone, masticadienoic acid (Z), masticadienoic acid (E), schinol, gallic acid and squalene, as well as a mixture with unsaturated fatty acid profile and a mixture with trisaccharide characteristics. Their chemical structures being determined by spectrophotometric methods such as 1H and 13C NMR, UV and MS. Two of the 17 EAMF extracts were selected, which were incorporated into an active high-methoxylation pectin-based film called "Extract 2" and "Extract 8" in various concentrations (0, 1, 3 and 5%). The films had a mean thickness of 0.007 mm for all concentrations of the extracts tested. It was observed in relation to the mechanical properties that there was an interaction of the polyphenolic components of the extracts with the materials used in the production of the films. The films were more permeable to water vapor (6.18-7.80 g.mm/m2.h.kPa) than the control film (5.12 g.mm/m2.h.kPa). The films of both extracts showed good thermal stability independent of the concentration tested. The films produced in this study presented antioxidant activity, and the films added from extract 8 presented the best% SRL values (54.45 and 67.08, respectively). All films obtained inhibition halo against the microorganisms tested. In view of the results, it can be inferred that FTS have antioxidant potential, antimicrobial activity and high inhibition of acetylcholinesterase and can be used in cosmetics, nutraceuticals and food industry, as well as a promising alternative in the production of active films.
O presente estudo teve como objetivo principal obter extratos bioativos dos frutos de Schinus terebinthifolius Raddi (STF), com a??o antioxidante e antimicrobiana, para incorpora??o em uma embalagem bioativa para alimentos, al?m de inibi??o da acetilcolinesterase. O processo de extra??o foi realizado por micro-ondas focalizado (EAMF) e ultrassom (EAU). A compara??o entre os m?todos de extra??o foi monitorada pelas atividades biol?gicas desses extratos. Os resultados mostraram que para o rendimento n?o teve diferen?a significativa. Para os ensaios de EAMF o melhor valor de fen?lico (5950 ? 1,4 mgGAE/g) e flavonoides totais (1750 ? 3,2 mgEQ/g) foi no tempo de extra??o de 25 minutos, na temperatura de 51 ?C e com 75% de etanol. Para os ensaios obtidos por EAU o melhor teor de fen?licos totais foi (92,2 ? 0,8 mgGAE /g) no ensaio EAU 10 (tempo de extra??o de 30 minutos, na temperatura de 42 ?C e com 50% de etanol) e de flavonoides (67,72 ? 1,0 mgEQ /g) no ensaio EAU 12(tempo de extra??o de 17,5 minutos, na temperatura de 60 ?C e com 50% de etanol). Os melhores valores para a percentagem de inibi??o (%SRL) foi de 87,3% (EAMF 8) e 31,3% (EAU 12). A an?lise por espectrometria de massa mostrou a presen?a de compostos fen?licos e terpenos. Em rela??o ? atividade antimicrobiana dos extratos obtidos por EAMF, a CIM para S. aureus foi de 0,5 mg/ml, para E. coli 0,25 mg/ml, enquanto que o extrato de EAU apresentou CIM de 0,5 mg/ml para os dois microrganismos analisados. No estudo fitoqu?mico foi poss?vel isolar 7 subst?ncias: agasthiflavona, tetrahidrorobustaflavona, ?cido masticadienoico (Z), ?cido masticadienoico (E), schinol, ?cido g?lico e o esqualeno, al?m de uma mistura com perfil de ?cidos graxos insaturados e uma mistura com caracter?stica de trissacar?deos. Sendo suas estruturas qu?micas determinadas por m?todos espectrom?tricos tais como RMN 1H e 13C, UV e EM. Selecionou-se 2 dos 17 extratos EAMF, os mesmos foram incorporados em um filme ativo, ? base de pectina de alta metoxila??o, denominados ?Extrato 2? e ?Extrato 8? em concentra??es diversas (0, 1, 3 e 5%). Os filmes apresentaram espessura m?dias de 0,007 mm para todas as concentra??es dos extratos testados. Observou-se em rela??o as propriedades mec?nicas que houve uma intera??o dos componentes polifen?licos dos extratos com os materiais utilizados na produ??o dos filmes. Os filmes foram mais perme?veis ao vapor d??gua (6,18?7,80 g.mm/m2.h.kPa) do que o filme controle (5,12 g.mm/m2.h.kPa). Os filmes de ambos extratos mostraram uma boa estabilidade t?rmica independente da concentra??o testada. Os filmes produzidos neste estudo apresentaram atividade antioxidante, sendo que os filmes adicionados do extrato 8 apresentaram os melhores valores de %SRL (54,45 e 67,08, respectivamente). Todos os filmes obtiveram halo de inibi??o contra os micro-organismo testados. Diante dos resultados encontrados pode-se inferir que os STF t?m potencial antioxidante, atividade antimicrobiana e alta inibi??o de acetilcolinesterase podendo ser utilizados em cosm?ticos, produtos nutrac?uticos e na ind?stria alimentar, al?m de uma alternativa promissora na produ??o de filmes ativos.
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Oliveira, José Cândido Selva de. "Estudo químico e avaliação biológica do extrato das cascas das raízes de Caesalpinia pyramidalis Tul (Leguminosae)." reponame:Repositório Institucional da UFBA, 2010. http://www.repositorio.ufba.br/ri/handle/ri/10699.

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CAPES
O presente trabalho relata o estudo químico das cascas das raízes de Caesalpinia pyramidalis Tul., uma árvore pertencente a família Leguminosae endêmica da região da caatinga baiana cujas folhas são utilizadas na medicina popular como diurético e digestivo. O extrato metanólico bruto foi submetido à extração liquido-liquido e sua atividade citotóxica e antioxidante foram avaliadas. O extrato hexânico apresentou-se atóxico para o teste de letalidade de Artemia salina e os demais extratos foram moderadamente tóxicos. Em relação à atividade antioxidante, o extrato AcOEt foi o mais ativo, seguido do BuOH e MeOH. O fracionamento cromatográfico da fase hexânica permitiu o isolamento do lupeol, acacetina, um novo fenilpropanóide, ácido (E)-8-hidroxi-3,5-dimetoxicumarico, além de uma mistura de sitosterol e estigmasterol. Da fase metanólica foram isolados o mesmo fenilpropanóide encontrado na hexânica além de um novo biflavonóide, 7-hidroxi-4’-metoxiflavona-5α-2,4- dihidroxi-4’-metoxidihidrochalcona. A estrutura deste novo biflavonóide bem como das outras substâncias isoladas foram elucidadas a partir da análise dos dados de RMN 1H e 13C (BB e APT) juntamente com a RMN de correlação (HMQC e HMBC).
Salvador
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9

Fidelis, Queli Cristina. "Metab?litos especiais isolados de folhas e galhos de Ouratea ferruginea Engl. (Ochnaceae)." Universidade Federal Rural do Rio de Janeiro, 2011. https://tede.ufrrj.br/jspui/handle/jspui/1138.

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Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico, CNPq, Brasil.
This work describes the phytochemical study of the stems and leaves of Ouratea ferruginea Engl., Ochnaceae. The material for study was collected in the campus of Embrapa in Bel?m, Par? state, and identified by Dra Silvane Taveres Rodrigues. The compounds described in this phytochemistry investigation were isolated by the solvents partition and chromatographyc techniques of the extracts obtained by maceration at room temperature with hexane, ethyl acetate and methanol. The structures were determined through analysis of data provided by IR, 1H and 13C NMR (1D an 2D techniques), mass spectrometry including GCMS and HPLC-MS of natural compounds and some derivatives. From the stem dichloromethane extract friedelin, friedelinol, sitosterol, stigmasterol, campesterol, 3-b-O-Dglucopyranosyl- stigmasterol, 2,6-dimethoxy?benzoquinine, 2,6-dimethoxy-hydroquinone, the isoflavones: 5,4'-dihydroxy-7,3',5'-trimethoxy-isoflavone, 5-hydroxy-7,3',4',5'-tetramethoxyisoflavone, 5,4'-dihydroxy-7,3'-dimethoxy-isoflavone, 7,5-dihydroxy-3',4',5'-trimethoxyisoflavone, 7,5,4?-trihydroxy-3?,5?-dimethoxy-isoflavone, and ferulic and syringic aldehyde were isolated. From the dichloromethane partition of the methanol extract of the stem vanillic acid, 4 ((1E)-3-hydroxy-1-propenyl)-2-methoxyphenol and 3,5-dimethoxy-4-hydroxydihydrocinamaldehyde were isolated. From hexane fraction of methanol extract from the leaves lupeone was isolated, and from the dichloromethane methanol partition were identified the biflavonoids amentoflavone and 7-methyl-amentoflavone, known as sequoiaflavone, along with syringic acid. From the ethyl acetate of the methanol extracts partition the epicatechin which absolute configuration was defined by circular dichroism spectral analysis was isolated. The sequioflanove is been identified in Ochnaceae for the first time. From the polar fraction the total phenol were determined by adapted Folin-Denis and precipitation with casein methods and by NMR spectral analysis.
Este trabalho descreve o estudo fitoqu?mico de caule e folhas da esp?cie vegetal Ouratea ferruginea Engl, Ochnaceae. O material para estudo foi coletado no campus da Embrapa em Bel?m do Par? e identificado pela Dra Silvane Tavares Rodrigues. As subst?ncias descritas nesta investiga??o fitoqu?mica foram isoladas atrav?s de parti??o com solventes e t?cnicas cromatogr?ficos de extratos obtidos atrav?s de macera??o a frio com hexano, acetato de etila e metanol. As estruturas foram determinadas atrav?s da an?lise de dados fornecidos por espectrometria na regi?o do infravermelho, RMN 1H e 13C (t?cnicas 1D e 2D), de massas incluindo CG-EM e CLAE-EM das subst?ncias naturais e de alguns derivados. Do extrato em diclorometano do caule foram isolados friedelina, friedelinol, sitosterol, estigmasterol, campesterol, 3-b-O-D-glicopiranosil-estigmasterol, 2,6-dimetoxi benzoquinona, 2,6-dimetoxi hidroquinona, as isoflavonas 5,4?-diidroxi-7,3?,5?-trimetoxiisoflavona, 5,4?-diidroxi-7,3?-dimetoxi-isoflavona, 5-hidroxi-7,3?,4?,5?-tetrametoxiisoflavona, 7,5-diidroxi-3?,4?,5?-trimetoxi-isoflavona, 7,5,4?-triidroxi-3?,5?-dimetoxiisoflavona, al?m dos alde?dos sir?ngico e fer?lico. Da parti??o em diclorometano do extrato metan?lico do caule foram isolados ?cido van?lico, 4((1E)-3-hidroxi-1-propenil)-2- metoxifenol e 3,5-dimetoxi-4-hidroxi-diidrocinamalde?do. Das folhas foi isolada a lupeona na parti??o em hexano do extrato metan?lico; e na parti??o em diclorometano foram identificados os biflavon?ides amentoflavona e 7-metil-amentoflavona, conhecida como sequoiaflavona, e o ?cido sir?ngico. Na parti??o em acetato de etila foi isolado a epicatequina cuja configura??o absoluta foi definida com an?lise do espectro de dicro?smo circular. A sequioflavona est? sendo registrada pela primeira vez em Ochnaceae. Das fra??es polares foram determinados o teor de fen?is totais e taninos por m?todos de Folin-Denis e precipita??o com case?na, adaptados, al?m de an?lise com espectros de RMN.
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10

Fernandes, Daniara Cristina. "Estudo químico e atividade biológica de Garcinia xanthochymus (Clusiaceae) /." Araraquara : [s.n.], 2010. http://hdl.handle.net/11449/97889.

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Orientador: Dulce Helena Siqueira Silva
Banca: Ian Castro Gamboa
Banca: Fernanda Rodrigues Garcez
Resumo: A espécie Garcinia xanthochymus, comumente conhecida como Gamboja, é uma árvore nativa da Índia com aproximadamente 8-10 metros, utilizada extensamente na medicina popular como antidiarréica. Este trabalho descreve o estudo químico e biológico das folhas e frutos de G. xanthochymus. Dentre as substâncias isoladas, podemos destacar 3 triterpenos obtidos do extrato hexânico das folhas: friedelina (1), lanosta-8,24-dien-3-ol (2) e lanosta-7,24-dien-3-ol (3), sendo as substâncias 2 e 3 relatadas pela primeira vez na literatura da espécie. A prospecção química da fase acetato de etila das folhas revelou uma abundante presença de biflavonóides, sendo as substâncias saharanflavona (4), I3, II8-biapigenina (5), GB1a (6), (+)-morelloflavona (8), GB2a (11), volkensiflavona (12), GB2 (14), xantochimusídeo (15) e fukugisídeo (16), caracterizadas pela ligação interflavonoídica do tipo 38'', e as substâncias podocarpusflavona (7) e amentoflavona (9), pela ligação do tipo 3'8''. Merece destaque a substância 4, isolada pela primeira vez de fontes naturais. A composição química de G. xanthochymus constituiu-se ainda das substâncias diidrokaempferol (10), ácido vanílico (13), cinco derivados de ácidos fenilpropanoídicos: ácido 3-O-cafeoilquínico (17), ácido 5-O-cafeoilquínico (18), ácido 3-p-coumaroilquínico (21), ácido 4-O-cafeoilquínico (22) e ácido 4-p-coumaroilquínico (23); e ainda a mistura binária das benzofenonas xantochimol (19) e cicloxantochimol (20). Todas as substâncias foram relatadas pela primeira vez nas folhas de G. xanthochymus, com exceção da substância 7 e as substâncias 10, 13, 17, 18, 21, 22 e 23 ainda não haviam sido identificadas na espécie. Através da técnica CG-DIC foram identificados 15 triterpenos e/ou esteróides nos extratos de baixa polaridade e através das técnicas hifenadas, como CLAE-UV e CLAE-EM, foi ... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The species Garcinia xanthochymus, known as Gamboja is a native Indian tree ca. 8-10 m high, which is extensively used as folk medicine for treating diarrhea and dysentery. This work describes the study of the chemical profile of G. xanthochymus leaves and fruits. Among the isolated substances three triterpenes were obtained from the hexane extract of the leaves: friedelin (1), lanosta-8,24-dien-3-ol (2) e lanosta-7,24-dien-3-ol (3), with compounds (2) and (3) described for the first time in the literature of this species. The chemical prospection of the ethyl acetate extract of the leaves revealed an abundant amount of biflavonoids, with compounds saharanflavone (4), I3,II8-biapigenin (5), GB1a (6), (+)-morelloflavone (8), GB2a (11), volkensiflavone (12), GB2 (14), xanthochymuside (15) and fukugiside (16) characterized by the interflavonoid 38" bond, and compounds podocarpusflavone (7) and amentoflavone (9), by the interflavonoid 3'8'' bond. Substance 4 was isolated for the first time from a natural source. The chemical composition of G. xanthochymus included additionally dihydrokaempferol (10), vanillic acid (13), and five phenylpropanoid acid derivatives: 3-O-caffeoylquinic acid (17), 5-O-caffeoylquinic acid (18), 3-p-coumaroylquinic acid (21), 4-O-caffeoylquinic acid (22) and 4-p-coumaroylquinic acid (23); as well a binary mixture of xanthochymol (19) and cycle-xanthochymol (20) benzophenones. All the compounds were reported for the first time in the leaves of G. xanthochymus, with the exception of compound 7, and compounds 10, 13, 17, 18, 21, 22 e 23, which had not yet been identified in this species. By CG-FID technique fifteen triterpenes and/or steroids were identified in the low polarity extracts. Hyphenated techniques such as HPLC-UV and HPLC-MS were used to locate previously isolated compounds from different fractions and/or isolated substances from other works... (Complete abstract click electronic access below)
Mestre
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Rahaoui, Hassan. "Application du couplage catalytique par voie boronique dans la synthèse d'arylflavonoïdes et de biflavonoïdes." Mulhouse, 1991. http://www.theses.fr/1991MULH0177.

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Le couplage catalytique aryle-aryle par voie boronique permet la réalisation de jonctions biaryle aussi bien symétriques que dissymétriques. Cette méthode consiste à faire réagir un dérivé iodé ou bromé avec un acide boronique en présence de catalyseur (palladium tétrakistriphénylphosphine Pd(TPP)4) et d'une base. Notre travail a été effectué dans le but d'étudier le domaine d'application du couplage boronique en fonction de l'encombrement tant du dérivé iodé (flavone ou 2-phenyl-4H-1-benzopyrane-4-one) que de l'acide boronique (phényl ou 8-flavonyl substitué par OCH3, OCH(CH3)2). Nous avons donc fait réagir des organoboriques avec des 3’-iodoflavones selon deux méthodes : la première met en oeuvre les acides boroniques, la deuxième utilise les esters boroniques. Dans le cas des 3’-arylflavones, nous avons appliqué le couplage avec les acides avec succès. Nous avons aussi mis en évidence les limites de cette méthode avec des acides arylboroniques ortho et ortho’ encombrés. L'utilisation, dans ces cas, d'esters boroniques avec le carbonate de thallium en milieu anhydre a permis de réussir le couplage avec succès. Dans le cas de biflavones, l'utilisation de la méthode des acides a été décevante. Mais le passage par les esters boroniques a permis d'accéder sans problèmes majeurs à des biflavonoïdes à jonction[I-3’, II-8] ou à jonction [I-8, II-8] : isoginkgétine, bilobétine, putraflavone et cupressusflavone
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12

Fernandes, Daniara Cristina [UNESP]. "Estudo químico e atividade biológica de Garcinia xanthochymus (Clusiaceae)." Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/97889.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
A espécie Garcinia xanthochymus, comumente conhecida como Gamboja, é uma árvore nativa da Índia com aproximadamente 8-10 metros, utilizada extensamente na medicina popular como antidiarréica. Este trabalho descreve o estudo químico e biológico das folhas e frutos de G. xanthochymus. Dentre as substâncias isoladas, podemos destacar 3 triterpenos obtidos do extrato hexânico das folhas: friedelina (1), lanosta-8,24-dien-3-ol (2) e lanosta-7,24-dien-3-ol (3), sendo as substâncias 2 e 3 relatadas pela primeira vez na literatura da espécie. A prospecção química da fase acetato de etila das folhas revelou uma abundante presença de biflavonóides, sendo as substâncias saharanflavona (4), I3, II8-biapigenina (5), GB1a (6), (+)-morelloflavona (8), GB2a (11), volkensiflavona (12), GB2 (14), xantochimusídeo (15) e fukugisídeo (16), caracterizadas pela ligação interflavonoídica do tipo 38’’, e as substâncias podocarpusflavona (7) e amentoflavona (9), pela ligação do tipo 3’8’’. Merece destaque a substância 4, isolada pela primeira vez de fontes naturais. A composição química de G. xanthochymus constituiu-se ainda das substâncias diidrokaempferol (10), ácido vanílico (13), cinco derivados de ácidos fenilpropanoídicos: ácido 3-O-cafeoilquínico (17), ácido 5-O-cafeoilquínico (18), ácido 3-p-coumaroilquínico (21), ácido 4-O-cafeoilquínico (22) e ácido 4-p-coumaroilquínico (23); e ainda a mistura binária das benzofenonas xantochimol (19) e cicloxantochimol (20). Todas as substâncias foram relatadas pela primeira vez nas folhas de G. xanthochymus, com exceção da substância 7 e as substâncias 10, 13, 17, 18, 21, 22 e 23 ainda não haviam sido identificadas na espécie. Através da técnica CG-DIC foram identificados 15 triterpenos e/ou esteróides nos extratos de baixa polaridade e através das técnicas hifenadas, como CLAE-UV e CLAE-EM, foi...
The species Garcinia xanthochymus, known as Gamboja is a native Indian tree ca. 8-10 m high, which is extensively used as folk medicine for treating diarrhea and dysentery. This work describes the study of the chemical profile of G. xanthochymus leaves and fruits. Among the isolated substances three triterpenes were obtained from the hexane extract of the leaves: friedelin (1), lanosta-8,24-dien-3-ol (2) e lanosta-7,24-dien-3-ol (3), with compounds (2) and (3) described for the first time in the literature of this species. The chemical prospection of the ethyl acetate extract of the leaves revealed an abundant amount of biflavonoids, with compounds saharanflavone (4), I3,II8-biapigenin (5), GB1a (6), (+)-morelloflavone (8), GB2a (11), volkensiflavone (12), GB2 (14), xanthochymuside (15) and fukugiside (16) characterized by the interflavonoid 38” bond, and compounds podocarpusflavone (7) and amentoflavone (9), by the interflavonoid 3’8’’ bond. Substance 4 was isolated for the first time from a natural source. The chemical composition of G. xanthochymus included additionally dihydrokaempferol (10), vanillic acid (13), and five phenylpropanoid acid derivatives: 3-O-caffeoylquinic acid (17), 5-O-caffeoylquinic acid (18), 3-p-coumaroylquinic acid (21), 4-O-caffeoylquinic acid (22) and 4-p-coumaroylquinic acid (23); as well a binary mixture of xanthochymol (19) and cycle-xanthochymol (20) benzophenones. All the compounds were reported for the first time in the leaves of G. xanthochymus, with the exception of compound 7, and compounds 10, 13, 17, 18, 21, 22 e 23, which had not yet been identified in this species. By CG-FID technique fifteen triterpenes and/or steroids were identified in the low polarity extracts. Hyphenated techniques such as HPLC-UV and HPLC-MS were used to locate previously isolated compounds from different fractions and/or isolated substances from other works... (Complete abstract click electronic access below)
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13

Marquet, Florence. "Garcinia kola Heckel." Paris 5, 1996. http://www.theses.fr/1996PA05P189.

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14

Osorio, Durango Edison Javier. "Búsqueda de sustancias bioactivas a partir de dos especies de la flora colombiana: alcaloides de "Phaedranassa dubia" (Amaryllidaceae) y biflavonoides de "Garcinia madruno" (Clusiaceae)." Doctoral thesis, Universitat de Barcelona, 2008. http://hdl.handle.net/10803/2618.

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El objetivo del presente trabajo ha sido la búsqueda de sustancias bioactivas en dos especies de la flora colombiana. Se pretendió aislar y caracterizar los metabolitos secundarios sintetizados por Phaedranassa dubia (Amaryllidaceae) y Garcinia madruno (Clusiaceae), además de estudiar la actividad antiprotozoaria in vitro y de evaluar la actividad antioxidante de los metabolitos aislados. El trabajo fitoquímico realizado con Phaedranassa dubia ha permitido el aislamiento de un nuevo alcaloide de tipo Amaryllidaceae, fedranamina, cuya estructura se ha establecido por análisis espectroscópicos (UV, EM, RMN y CD). Otros alcaloides identificados en esta especie han sido: pseudolicorina, sanguinina, galantamina, epinorgalantamina, hemantamina, ungeremina y zefbetaina. De otro lado, se ha reportado por primera vez el producto natural 7'-O-(6'-acetil)-glucósido de morelloflavona, al cual se ha dado el nombre trivial de madrunoudeasido, un nuevo biflavonoide aislado del extracto metanólico de las partes aéreas de Garcinia madruno (Clusiaceae). Es la primera vez que se reporta un biflavonoide acetil-glucósido, aislado del género Garcinia. Igualmente se reportan los biflavonoides amentoflavona, morelloflavona, volkensiflavona, fukugisido y spicatasido, a partir de la misma especie vegetal. La evaluación in vitro frente a cuatro diferentes parasitos antiprotozoarios se realizó utilizando los diferentes compuestos. Los alcaloides ungeremina, pseudolicorina y hemantamina presentaron buena actividad en el ensayo in vitro frente a Trypanosoma brucei rhodesiense, T. cruzi y Plasmodium falciparum con valores de IC50 menores de 1 µg/mL. Se ha estudiado, igualmente, la actividad antioxidante de los biflavonoides aislados de G. madruno, por medio de los métodos del 2,2'-difenil-1-picrilhidracil (DPPH·) y de la inhibición de la peroxidación de lipoproteínas de baja densidad (LDL). En general, los compuestos con enlace inter-flavonoide C3→C8' presentan una potente actividad captadora de radicales DPPH·. Los biflavonoides que presentan esta característica en combinación con una sustitución 3',4'-dihidroxi (catecol) en el anillo E, un doble enlace entre C-2' y C-3' y una función carbonilo en la posición C-4', son los captadores de radicales más activos. En relación a los inhibidores de la peroxidación de LDL, los mejores inhibidores son los compuestos con enlace inter-flavonoide C3→C8': morelloflavona y volkensiflavona. la fracción biflavonoide (FB) aislada de G. madruno, compuesta principalmente por morelloflavona, volkensiflavona y amentoflavona. Los datos sugieren que FB podría ser un excelente candidato para ser utilizado como antioxidante. Es probable que se produzcan procesos de sinergismo en la FB, toda vez que presenta una actividad captadora de radicales y una inhibición de la peroxidación de LDL superior, en algunos casos, a los compuestos más activos.
The bulbs of Phaedranassa dubia (Amaryllidaceae) were found to contain the novel compound phaedranamine, together with seven known alkaloids. The structure and stereochemistry of the alkaloids were determined by physical and spectroscopic methods. An in vitro screening against four different parasitic protozoa was carried out using the isolated compounds. The alkaloids ungeremine, pseudolycorine and haemanthamine showed good activity in in vitro assays against Trypanosoma brucei rhodesiense, T. cruzi and Plasmodium falciparum with IC50 values in the range of 1 µg/mL or lower. On the other hand, six biflavonoids were isolated from Garcinia madruno (Clusiaceae) and then 7"-O-(6""-acetyl)-glucoside of morelloflavone (5) has proven to be a new compound. The antioxidant activity of the biflavonoids against low-density lipoproteins peroxidation was studied by means of TBARS assay. The antioxidant potential of a biflavonoid fraction (BF) was also evaluated and correlated with its biflavonoid content. Lipid peroxidation was significantly reduced in the presence of the BF, morelloflavone being mainly responsible for this effect.
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15

Ayepola, Omolola Rebecca. "Effects of kolaviron–a Garcinia kola biflavonoid on biochemical and histological parameters in streptozotocin - induced diabetes and diabetic complications (nephrotoxicity and hepatotoxicity) in male Wistar rats." Thesis, Cape Peninsula University of Technology, 2014. http://hdl.handle.net/20.500.11838/1512.

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Thesis submitted in fulfillment of the requirements for the Doctor of Technology: Biomedical Technology In the Faculty of Health and Wellness At the CAPE PENINSULA UNIVERSITY OF TECHNOLOGY 2014
Diabetes mellitus (DM) results in severe metabolic imbalances and pathological changes in many tissues. Chronic inflammation and oxidative stress have been implicated in the pathophysiology of diabetes mellitus. Garcinia kola (Family: Guttiferae) is a plant well known for its ample medicinal values. The seed of the plant also known as ‘bitter kola’ due to its bitter taste is used as a masticatory agent in traditional hospitality, cultural and social ceremonies in Africa. Kolaviron (KV) is a defatted ethanol extract from the seeds of Garcinia kola (GK). Kolaviron has been shown in experimental models of diseases to have numerous beneficial effects due to the presence of flavonoids (mainly Garcinia biflavonoid (GB)-1, GB-2 and kolaflavanone). However, there is paucity of information regarding the possible effect of kolaviron on inflammatory mediators and oxidative stress in diabetes mellitus. Therefore, this study was carried out to investigate the potential beneficial effects of kolaviron on antioxidant status, inflammatory mediators and apoptosis. Other biochemical and histological alterations in the blood, liver and kidney of streptozotocin-induced diabetic rats were also evaluated. A single intraperitoneal injection of freshly prepared solution of streptozotocin (50 mg/kg.b.wt.) in citrate buffer (0.1M, pH 4.5) was administered to overnight fasted rats for diabetes induction. Diabetes was confirmed by stable hyperglycemia (>18 mmol/l) in the tail blood glucose after 5 days of streptozotocin injection. Kolaviron (100 mg/kg b.wt.) was administered to diabetic rats (by gastric gavage) on the 6th day after the induction of diabetes and treatment continued for 6 weeks (5 times weekly). The effects on blood glucose, body weight, organ (liver and kidney) weight, serum biochemical parameters, oxidative status, inflammatory mediators and histology of the liver, kidney and pancreas were assessed. Kolaviron (KV) treatment lowered blood glucose in diabetic and normoglycemic rats and reduced glycated haemoglobin [HbA1C (%)]. Plasma insulin level was raised in diabetic rats treated with KV. Histomorphometric analysis of the pancreas revealed increased β-cell area of pancreatic islets of kolaviron-treated diabetic group. The indices of organ (liver and kidney) damage were increased in diabetic rats. However, KV treatment protected against liver and kidney damage. The characteristic features of diabetic dyslipidemia such as elevated serum triglyceride and cholesterol concentration which are major risk factors for cardiovascular disease were also significantly reduced in KV-treated diabetic rats. Alteration in antioxidant enzymes status was observed in the liver, kidney and blood (erythrocyte, plasma and serum) of diabetic rats. Lowered catalase (CAT) activity was observed in the liver and kidney of diabetic rats while KV treatment significantly (p < 0.05) elevated catalase activity in the liver and kidney. There was no significant change (p > 0.05) in erythrocyte catalase activity among all treatment groups. Erythrocyte of diabetic rats showed a marked reduction in the activity of superoxide dismutase (SOD) with no significant changes in liver and kidney SOD activity of diabetic rats compared to control whereas KV administration to rats markedly increased SOD activity. Glutathione peroxidase (GPX) activity was elevated in the erythrocyte and kidney of STZ-induced diabetic rats with no significant effect on liver GPX activity. KV treatment reversed the alteration in GPX activity in the kidney and erythrocyte. Level of reduced glutathione (GSH), a non-enzymatic antioxidant was decreased in the both liver and kidney of diabetic rats and treatment of diabetic rats with KV elevated GSH concentration in both tissues. Also, malondialdehyde (MDA), a marker of lipid peroxidation was elevated in the liver, kidney and plasma of diabetic rats and significantly (p < 0.05) lowered following KV treatment. Diabetes induction reduced the capacity of liver and kidney to absorb oxygen radicals as demonstrated by lowered oxygen radical absorbance capacity (ORAC) values. KV administration to normal and diabetic rats significantly increased ORAC values. Increased rate of apoptosis, a major cellular response to high glucose induced stress was observed in the renal and hepatic tissues of diabetic control rats. Kolaviron treatment of diabetic rats protected the liver and kidney against hyperglycemia-induced apoptosis and decreased the number of TUNEL positive cells A significant (p < 0.05) elevation of pro-inflammatory cytokines; monocyte chemoattractant protein (MCP-1), Interleukin-1β (IL-1β), IL-6 and tumor necrosis factor (TNF)-𝛂 was observed in the liver of diabetes rats. KV treatment lowered these inflammatory biomarkers. On the other hand, the kidney of diabetic rats showed elevated concentration of pro-inflammatory IL-1β with no significant effect on kidney TNF-𝛂. An increase in the serum concentration of MCP-1 and IL-1β was observed in the untreated diabetic rats while kolaviron treatment normalized the alteration in serum concentration of MCP-1, IL-1β and vascular endothelial growth factor (VEGF). In conclusion, persistent and chronic hyperglycemia promotes the generation of free radicals and inflammatory molecules which contributes to progressive development of micro- and macro vascular complications and multi-organ damage. Kolaviron demonstrated beneficial effects on markers of oxidative stress and inflammation in the diabetic rats and also promoted the survival and functional integrity of the liver and kidney.
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16

Ndoile, Monica Mbaraka. "Structure, synthesis and biological activities of biflavonoids isolated from Ochna serrulata (Hochst.) Walp." Thesis, 2012. http://hdl.handle.net/10413/8586.

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The phytochemistry of Ochna serrulata (Hochst.) Walp. was investigated for the first time; two new dimeric chalcones (5-deoxyurundeuvine C and serrulone A) and two new biflavonoid derivatives (4,4’,7-tri-O-methylisocampylospermone A and 4”’-de-Omethylafzelone A) were isolated. These compounds were isolated along with the known compounds lophirone A, afzelone B, campylospermone A, isocampylospermone A, ochnaflavone, 2”,3”-dihydroochnaflavone, lophirone C, psilosin, 3’-O-methylpsilosin, a cyanoglucoside, epicatechin, (2’,4’- dihydroxyphenyl)acetic acid, methyl (2’,4’-dihydroxyphenyl)acetate, irisolone 4’- methyl ether, iriskumaonin 3’-methyl ether, 3',4'-dimethoxy-6,7-methylenedioxyisoflavone, lophirone L, syringaresinol and 16α,17-dihydroxy-entkauran-19-oic acid. The growth inhibitory effect of these compounds was evaluated against three cancer cell line panel of TK 10 (renal), UACC62 (melanoma) and MCF7 (breast) using a sulforhodamine B (SRB) assay. Ochnaflavone and 3’-methoxypsilosin demonstrated selectivity and only inhibited the growth of melanoma cancer cells. However, ochnaflavone showed higher activity by totally inhibiting the growth of melanoma cancer cells at 12.91 μM, whereas, 3’-O-methylpsilosin has this effect at a concentration of 14.11 μM. Lophirone C, a dimeric chalcone, demonstrated the highest cytotoxic activity amongst all isolated compounds against renal, melanoma and breast cancer cells with TGI at 35.63 μM, 11.67 μM and 30.35 μM, respectively. Lophirone A, a rearranged biflavonoid, showed TGI against these cancer cells at 58.96 μM, 26.23 μM and 40.01 μM, respectively. The rest of the compounds showed no significant cytotoxicity against the three cancer cells. The new biflavonoid, 4,4’,7-tri-O-methylisocampylospermone A demonstrated the highest antimalarial activity against chloroquine-resistant strains of Plasmodium falciparum (FCR-3) with IC50 of 11.46 μM, followed by ochnaflavone (17.25 μM). iv Serrulone A (26.52 μM), lophirone A (29.78 μM), 5-deoxyurundeuvine C (31.07 μM), lophirone C (35.31 μM), 4”’-de-O-methylafzelone A (38.43 μM), afzelone B (39.54 μM), irisolone 4’-methyl ether (40.72 μM) and syringaresinol (42.66 μM) were moderately active. The following compounds exhibited the lowest antimalarial activity, 2”,3”-dihydroochnaflavone (61.86 μM), iriskumaonin 3’-O-methyl ether (93.69 μM),3’- O-methylpsilosin (106.35 μM) and16α,17-dihydroxy-ent-kauran-19-oic acid (106.48 μM). Owing to the observed and reported biological/pharmacological activity, ochnaflavone (an ether-linked biflavone consisting of apigenin and luteolin moieties) was selected for synthetic studies. An older method, nucleophilic aromatic substitution (SNAr) was successfully applied in the construction of the diary ether. Oxidative ring cyclization of the ether-linked dimeric chalcone was achieved by using heated pyridine and iodine. The two methods can be extended further in the synthesis of other novel biflavones with ether linkage.
Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.
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17

Lin, Yan-zhi, and 林彥至. "Assessment of the inhibiting effectiveness on the enterovirus by biflavonoids and Coptis chinensis." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/2nxgt2.

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碩士
中臺科技大學
生命科學研究所
96
Enterovirus 71 (EV71), an important human pathogenic virus,belonged to the Enterovirus genus of Picornaviridae family. Picornavirus is a small, non-enveloped virus with positive single-stranded RNA. In 1998, there was a large enterovirus outbreak caused by EV71 in Taiwan, causing more than 120,000 infected and 78 deaths. In each year, chance or regional outbreaks of enterovirus infection are reported all over the world, especially in the tropical and sub-tropical regions. The pre-school children are most vulnerable to EV71 infection. EV71 infection may cause some clinical symdromes, mainly hand, foot and mouse disease, and is notable for its invasion to central nervous system (CNS), leading to neurological defects and even death. Since there is no vaccine or antiviral agent available to be effective in treating or preventing EV71 infection, the specific aim of this study is to search for some extracts from natural plants that can inhibit enterovirus infection. The results showed that amentoflavone and the crude aqueous extract of Coptis chinensis are effective in inhibiting viral activity. The decrease of plaque reproduction in either drug treated virus at “absorption” stage implies viral replication was blocked at early stage of life cycle. Western blot and RT-PCR analysis indicated that amentoflavone can inhibit the translation of the virus and viral RNA synthesis. In the animal assessments, amentoflavone or the crude aqueous extract of Coptis chinensis treatments increased the survival rate of ICR mice that were challenged with lethal dose of virus. The results of in vivo and in vitro assays provided evidence that EV71 activity was efficiently inhibited by amentoflavone or the crude aqueous extract of Coptis chinensis, which may be considered as an antiviral drugs. In addition, amentoflavone was found to have inhibitory effects on other enteroviruses, including coxsackievirus B3, coxsackievirus B4 and coxsackievirus B5.
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18

"Antioxidative and vascular relaxing effects of black tea theaflavins." 2003. http://library.cuhk.edu.hk/record=b6073560.

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by Su Ya Lun.
"August 2003."
Thesis (Ph.D.)--Chinese University of Hong Kong, 2003.
Includes bibliographical references (p. 163-181).
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Mode of access: World Wide Web.
Abstracts in English and Chinese.
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19

Hillhouse, Brian Jason. "Screening of biflavonoid compounds and British Columbian bryophytes for antiviral activity against potato virus X." Thesis, 2003. http://hdl.handle.net/2429/14125.

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Plant viruses are responsible for causing significant losses to the agricultural industry. Recent investigations of antiviral compounds have suggested that biflavonoids may be a group of compounds which cause powerful inhibition to a broad spectrum of viral pathogens. Due to the high content of biflavonoids reported in bryophytes, this project has screened 50 bryophyte samples which represent 41 species for Potato Virus X (PVX) inhibition using a local lesion assay in Chenopodium quinoa. As a result of this screening, bryophytes have been identified as a prominent antiviral group; 29 of the 41 species were shown to cause greater than 75% inhibition when tested at 9.1 mg/mL. In addition to screening bryophyte extracts, several biflavonoid compounds were tested directly. When tested at 1.38 mg/mL robustaflavone and hinokiflavone where shown to be highly antiviral and exhibited PVX inhibitions of 85% and 78% respectively. Amentoflavone-7,4',4'trimethyl ether showed a marginal PVX inhibition of 29% and amentoflavone did not inhibit PVX at this concentration. Several compounds from the Columbian medicinal plant Iryanthera megistophylla have also been screened for inhibition of PVX. Of these compounds, iryanterin K, cinchonain Ib, cinchonain Ia, procyanidin B-2 and cinchonain IIa have been shown to be highly active against PVX when tested at 9.1 mg/mL.
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20

Tsai, Shuo Kai, and 蔡碩愷. "Study on the apoptotic mechanisms of Ginkgetin,a biflavonoid from Ginkgo biloba L., in OVCAR-3 cells." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/92027071625377492017.

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碩士
國立陽明大學
生物化學研究所
88
Ginkgetin, a biflavonoid, is an extract from Ginkgo biloba L. This compound is reported to have an effect on the selective inhibition on the growth of human ovarian carcinoma (OVCAR-3). Based on the MTT assay, we could demonstrate the survival rate decreased with the elevated concentration of Ginkgetin. Moreover, this effect showed a dose-response relationship. The data from electrophoresis, TUNEL assay and flow cytometry demonstrated those features of apoptosis such as DNA fragmentation, chromatin condensation as well as sub-G0/G1 peak could be observed after treating OVCAR-3 with 10 g/ml Ginkgetin for 12 hours. This result implied the cytotoxic effect may be the direct cause of apoptosis of OVCAR-3.and we could confirm Ginkgetin induces the apoptosis of OVCAR-3. Based upon the test on the caspase activity, we observed the activity of CPP32/YAMA increased with the time. In addition, the result of Western Blot showed the substrate of CPP32/YAMA, PARP, was cleaved by the enzyme more completely, when the activity of CPP32/YAMA was elevated, whereas the activity of caspase 9 did not change. Besides, the caspase inhibitor, z-VAD-fmk, was capable of effectively inhibiting the induction of apoptosis of OVCAR-3 by Ginkgetin after treating the cells with 50 M z-VAD-fmk for 2 hour and subsequently with 10 g/ml Ginkgetin for 24 hours. Ginkgetin is a kind of polyphenolic compound. The result indicated that GKT kills OVCAR-3, through intracellular oxidative stress and lead to apoptosis. In our result, the catalase was found to have the strongest antioxidant effect, when the tumor cells were pre-treated with vitamine C, N-acetylcysteine, and catalase respectively. Our preliminary result demonstrated the apoptosis of OVCAR-3 by Ginkgetin underwent the same signaling pathway through CPP32/YAMA as reported by Shiah et al., but not through caspase 9.This result implicated the apoptosis induced by Ginkgetin maybe undergo the pathway mediated by JNK still need to be investigated. 英文摘要---------------------------------3 緒言-------------------------------------5 材料與方法------------------------------12 實驗結果--------------------------------29 討論------------------------------------33 參考文獻--------------------------------36 附圖------------------------------------42
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21

Hao-Hsuan, Chuang, and 莊皓宣. "Study on the Cytotoxic Mechanisms of Ginkgetin, a Biflavonoid Isolated from Selaginella Moellendorffii Hieron, in OVCAR-3 cells." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/31211678416873589116.

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碩士
國立陽明大學
藥理學研究所
89
Ginkgetin, a biflavonoid compound isolated from Selaginella moellendorffii, was reported to possess a selectively inhibitory effect on the growth of human ovarian adenocarcinoma (OVCAR-3) cells. To examine whether Ginkgetin also has a selective cytotoxic effect, MTT assays were performed using three different human cell lines: OVCAR-3, HeLa (human cervical carcinoma cell lines) and FS-5 (human foreskin fibroblast) as targets. We found that Ginkgetin kills OVCAR-3 cells with an EC50 equals to 3.0 mg/ml, while EC50 of this compound on HeLa and FS-5 cells was 5.2 mg/ml and 8.3 mg/ml, respectively. To examine the possible involvement of apoptosis in the toxic effect of Ginkgetin on OVCAR-3 cells, their morphology was first examined by light microscopy. During drug treatment, cell shrinkage and detachment from dish were observed. Moreover, when cell lysates prepared from OVCAR-3 cells after incubating with 3 mg/ml and 5 mg/ml of Ginkgetin for 48 h were subjected to agarose gel electrophoretic analysis, and the characteristic pattern of inter-nucleosomal DNA fragmentation was also observed. These results suggest that Ginkgetin kills OVCAR-3 cells through an apoptotic pathway. Because Ginkgetin is a polyphenolic compound, whose apoptotic effect may mediate through inducing intracellular oxidative damage, we therefore examined whether antioxidants can protect cells against the toxicity of this compound. We found that pre-treatment with vitamin C, vitamin E and catalase increases the viability of cells, and pretreatment with catalase also reduces DNA fragmentation caused by Ginkgetin, especially when high dose (5 mg/ml) of Ginkgetin was used. Since DNA is a major target for reactive oxygen species (ROS), DNA damage induced by Ginkgetin was then examined by a sensitive fluorometric method. High degrees of double-stranded DNA breakage were detected after cells were treated with 3 mg/ml and 5 mg/ml of Ginkgetin for 24 h, and such damage could greatly be reduced by the addition of 1000 U/ml of catalase 1.5 h before treatment with Ginkgetin. These results indicate that the toxicity of Ginkgetin on OVCAR-3 cells is mediated at least in part by inducing oxidative stress. z-VAD-fmk, a caspase inhibitor with broad specificity, was shown to be able to increase cell survival significantly when added simultaneously with Ginkgetin. This result indicates the participation of caspase(s) in the apoptosis induced by Ginkgetin. However, co-addition of catalase with z-VAD-fmk did not further increase cell survival. Therefore, we concluded that in addition to oxidative damage, other mechanisms may also be involved in the apoptosis of OVCAR-3 cells induced by Ginkgetin. We also found that the protective effects of both anti-oxidants and z-VAD-fmk on cells treated with 3 mg/ml of Ginkgetin was lower than those treated with 5 mg/ml of similar compound. These results indicate that oxidative damage is the major cause of apoptosis when cells treated with high dose (5 mg/ml). On the other hand, oxidative damage seems to play a very minor role in apoptosis induced by low dose of Ginkgetin, suggesting other mechanism(s) is involved in this apoptosis process.
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