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Produkce sekundárních metabolitů v explantátových kulturách třezalky tečkované / Secondary metabolite production in explantate cultures of St. John's worthKřížová, Šárka January 2013 (has links)
Secondary metabolite production in explantate cultures of St. John's Wort Šárka Křížová Diploma thesis Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Pharmacy Key words: St. John's Wort, elicitation, flavonoids, hydrogen peroxide, glutathion, neutral red. The goal of the diploma thesis was to influence the production of secondary metabolites (flavonoids) in explantate cultures of St. John's Wort. Method of elicitation was used. This method is based on adding of an elicitor (stressor) to the tissue culture. Suspensional and callus cultures of Hypericum Perforatum L. were used for experiments with potential elicitors: hydrogen peroxide, combination of hydrogen peroxide and Mg-ATP, glutathion and cellular pigment neutral red. Their effect to the production of flavonoids was evaluated after 4 and 24 hours. Cultures were cultivated on Murashige and Skoog medium with the addition of a growth hormone BAP and a growth stimulator α-NAO. HPLC method was used for analysis of the samples. Hydrogen peroxide raised the production of flavonoids, especially in suspensional cultures, in callus cultures the highest influence had glutathion (reduced form) and neutral red. The highest production of flavonoids was reached after 24 hours by addition of hydrogen peroxide in concentration 100 mg/l,...
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Genetic variation in Hypericum perforatum L. and resistance to the biological control agent Aculus hyperici liro /Mayo, Gwenda Mary. January 2004 (has links) (PDF)
Thesis (Ph.D.)--University of Adelaide, School of Agriculture and Wine, Discipline of Plant and Pest Science, 2004. / "October 2004" Includes bibliographical references (leaves 223-243).
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Access factors associated with the use of St. John's wort among adults with depressive symptomsWu, Chung-Hsuen. January 2006 (has links) (PDF)
Thesis (Master of Health Policy and Administration)--Washington State University, May 2006. / Includes bibliographical references (p. 29-36).
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Estudo da constituição química de hypericum carinatum (guttiferae) e avaliação da atividade inseticida de hypericum polyanthemum / Study of chemical constituints from Hypericum carinatum (Guttiferae) and insecticidal activity value from Hypericum polyanthemumAlbring, Daniela Vicentini January 2006 (has links)
O gênero Hypericum, família Guttiferae, engloba uma grande variedade de espécies, tendo para várias delas relatos de uso popular na terapêutica. Na região sul do Brasil ocorrem cerca de 20 espécies. Algumas delas vêm sendo estudadas e compostos de interesse farmacológico vêm sendo obtidos. Desta forma, para aprofundar estudos pré-existentes, deu-se continuidade à análise química de Hypericum carinatum e a investigação do potencial inseticida de Hypericum polyanthemum, ambas espécies nativas do RS. A partir do extrato hexânico de Hypericum carinatum, foram isolados e identificados, por métodos espectroscópicos, o derivado de floroglucinol uliginosina B e as benzofenonas carifenona A e carifenona B, as duas últimas de ocorrência restrita a esta espécie até o momento. Os demais compostos, isolados em menor quantidade, foram insuficientes para identificação espectroscópica.Da fração acetato de etila desta mesma espécie, dois flavonóides foram identificados, um deles o hiperosídeo, confirmado por CCD comparativa com padrão, e quercitrina, identificada por RMN 1H. Nos experimentos para avaliação da atividade inseticida foi utilizado o inseto Dysdercus peruvianus, uma praga do algodoeiro. Testes realizados com o extrato hexano de Hypericum polyanthemum demonstraram uma potencial atividade inseticida, visto que existe uma tendência a fagoinibição a partir da concentração de 1%. O fato de haver na literatura relatos de atividade inseticida para compostos derivados de benzopiranos, como o precoceno I e II, encecalina e desmetilencecalina, impulsionou a realização de ensaios com os benzopiranos isolados do extrato acima. Foram então analisados os produtos HP1 (6-isobutiril- 5,7-dimetóxi-2,2-dimetil-benzopirano), HP2 (7-hidróxi-6-isobutiril-5-metóxi-2,2- dimetil-benzopirano) e HP3 (5-hidróxi-6-isobutiril-7-metóxi-2,2-dimetilbenzopirano), sendo que apenas HP2 apresentou perfil inseticida, na concentração de 0,2%. / The genus Hypericum, family Guttiferae encompasses a great number of species many of them used in the popular medicine. In the southern Brazil there are approximately 20 species. Some of these species have been studied and interesting compounds in the pharmacological point of view have been isolated. In this way, aiming to continue the studies with the Hypericum species, in this work we investigated the chemical composition of H. carinatum and evaluated the potencial insecticide of H. polyanthemum, both species native to south Brazil. From the hexane extract of Hypericum carinatum we isolated and identificated by spectroscopic methods the phloroglucinol derivative uliginosin B and the benzophenones carifenone A e carifenone B, both restrict to this species until now. The other compounds, isolated in very small amount were not sufficient for the spectroscopic analysis. From the ethyl acetate fraction of this species there were obtained two flavonoids, one of them identified as hyperoside by chromatographic comparison with authentic sample and the other, quercitrin, identified by NMR spectroscopy. In the insecticidal experiments it was used the cotton stainer, Dysdercus peruvianus.Tests performed with the hexane extract demonstrated a potential insecticidal activity since it was observed a tendency of phago-inhibition in concentrations up to 1%. The well established insecticidal activity of benzopyran derivatives as precocene I, precocene II, encecalin and demethylencecalin led us to investigate the activity of the benzopyrans isolated from the above extrac. There were analysed the compounds HP1 (6-isobutyiryl-5,7-dimethoxy-2,2-dimethyilbenzopyran), HP2 (7-hydroxi-6-isobutyryl-5-methoxi-2,2-dimethyl-benzopyran) and HP3 (5-hydroxi-6-isobutyryl-7-methoxi-2,2-dimethyl-benzopyran). Only HP2 presented insecticidal activity at the concentration of 0,2%.
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Estudo da constituição química de hypericum carinatum (guttiferae) e avaliação da atividade inseticida de hypericum polyanthemum / Study of chemical constituints from Hypericum carinatum (Guttiferae) and insecticidal activity value from Hypericum polyanthemumAlbring, Daniela Vicentini January 2006 (has links)
O gênero Hypericum, família Guttiferae, engloba uma grande variedade de espécies, tendo para várias delas relatos de uso popular na terapêutica. Na região sul do Brasil ocorrem cerca de 20 espécies. Algumas delas vêm sendo estudadas e compostos de interesse farmacológico vêm sendo obtidos. Desta forma, para aprofundar estudos pré-existentes, deu-se continuidade à análise química de Hypericum carinatum e a investigação do potencial inseticida de Hypericum polyanthemum, ambas espécies nativas do RS. A partir do extrato hexânico de Hypericum carinatum, foram isolados e identificados, por métodos espectroscópicos, o derivado de floroglucinol uliginosina B e as benzofenonas carifenona A e carifenona B, as duas últimas de ocorrência restrita a esta espécie até o momento. Os demais compostos, isolados em menor quantidade, foram insuficientes para identificação espectroscópica.Da fração acetato de etila desta mesma espécie, dois flavonóides foram identificados, um deles o hiperosídeo, confirmado por CCD comparativa com padrão, e quercitrina, identificada por RMN 1H. Nos experimentos para avaliação da atividade inseticida foi utilizado o inseto Dysdercus peruvianus, uma praga do algodoeiro. Testes realizados com o extrato hexano de Hypericum polyanthemum demonstraram uma potencial atividade inseticida, visto que existe uma tendência a fagoinibição a partir da concentração de 1%. O fato de haver na literatura relatos de atividade inseticida para compostos derivados de benzopiranos, como o precoceno I e II, encecalina e desmetilencecalina, impulsionou a realização de ensaios com os benzopiranos isolados do extrato acima. Foram então analisados os produtos HP1 (6-isobutiril- 5,7-dimetóxi-2,2-dimetil-benzopirano), HP2 (7-hidróxi-6-isobutiril-5-metóxi-2,2- dimetil-benzopirano) e HP3 (5-hidróxi-6-isobutiril-7-metóxi-2,2-dimetilbenzopirano), sendo que apenas HP2 apresentou perfil inseticida, na concentração de 0,2%. / The genus Hypericum, family Guttiferae encompasses a great number of species many of them used in the popular medicine. In the southern Brazil there are approximately 20 species. Some of these species have been studied and interesting compounds in the pharmacological point of view have been isolated. In this way, aiming to continue the studies with the Hypericum species, in this work we investigated the chemical composition of H. carinatum and evaluated the potencial insecticide of H. polyanthemum, both species native to south Brazil. From the hexane extract of Hypericum carinatum we isolated and identificated by spectroscopic methods the phloroglucinol derivative uliginosin B and the benzophenones carifenone A e carifenone B, both restrict to this species until now. The other compounds, isolated in very small amount were not sufficient for the spectroscopic analysis. From the ethyl acetate fraction of this species there were obtained two flavonoids, one of them identified as hyperoside by chromatographic comparison with authentic sample and the other, quercitrin, identified by NMR spectroscopy. In the insecticidal experiments it was used the cotton stainer, Dysdercus peruvianus.Tests performed with the hexane extract demonstrated a potential insecticidal activity since it was observed a tendency of phago-inhibition in concentrations up to 1%. The well established insecticidal activity of benzopyran derivatives as precocene I, precocene II, encecalin and demethylencecalin led us to investigate the activity of the benzopyrans isolated from the above extrac. There were analysed the compounds HP1 (6-isobutyiryl-5,7-dimethoxy-2,2-dimethyilbenzopyran), HP2 (7-hydroxi-6-isobutyryl-5-methoxi-2,2-dimethyl-benzopyran) and HP3 (5-hydroxi-6-isobutyryl-7-methoxi-2,2-dimethyl-benzopyran). Only HP2 presented insecticidal activity at the concentration of 0,2%.
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Estudo da constituição química de hypericum carinatum (guttiferae) e avaliação da atividade inseticida de hypericum polyanthemum / Study of chemical constituints from Hypericum carinatum (Guttiferae) and insecticidal activity value from Hypericum polyanthemumAlbring, Daniela Vicentini January 2006 (has links)
O gênero Hypericum, família Guttiferae, engloba uma grande variedade de espécies, tendo para várias delas relatos de uso popular na terapêutica. Na região sul do Brasil ocorrem cerca de 20 espécies. Algumas delas vêm sendo estudadas e compostos de interesse farmacológico vêm sendo obtidos. Desta forma, para aprofundar estudos pré-existentes, deu-se continuidade à análise química de Hypericum carinatum e a investigação do potencial inseticida de Hypericum polyanthemum, ambas espécies nativas do RS. A partir do extrato hexânico de Hypericum carinatum, foram isolados e identificados, por métodos espectroscópicos, o derivado de floroglucinol uliginosina B e as benzofenonas carifenona A e carifenona B, as duas últimas de ocorrência restrita a esta espécie até o momento. Os demais compostos, isolados em menor quantidade, foram insuficientes para identificação espectroscópica.Da fração acetato de etila desta mesma espécie, dois flavonóides foram identificados, um deles o hiperosídeo, confirmado por CCD comparativa com padrão, e quercitrina, identificada por RMN 1H. Nos experimentos para avaliação da atividade inseticida foi utilizado o inseto Dysdercus peruvianus, uma praga do algodoeiro. Testes realizados com o extrato hexano de Hypericum polyanthemum demonstraram uma potencial atividade inseticida, visto que existe uma tendência a fagoinibição a partir da concentração de 1%. O fato de haver na literatura relatos de atividade inseticida para compostos derivados de benzopiranos, como o precoceno I e II, encecalina e desmetilencecalina, impulsionou a realização de ensaios com os benzopiranos isolados do extrato acima. Foram então analisados os produtos HP1 (6-isobutiril- 5,7-dimetóxi-2,2-dimetil-benzopirano), HP2 (7-hidróxi-6-isobutiril-5-metóxi-2,2- dimetil-benzopirano) e HP3 (5-hidróxi-6-isobutiril-7-metóxi-2,2-dimetilbenzopirano), sendo que apenas HP2 apresentou perfil inseticida, na concentração de 0,2%. / The genus Hypericum, family Guttiferae encompasses a great number of species many of them used in the popular medicine. In the southern Brazil there are approximately 20 species. Some of these species have been studied and interesting compounds in the pharmacological point of view have been isolated. In this way, aiming to continue the studies with the Hypericum species, in this work we investigated the chemical composition of H. carinatum and evaluated the potencial insecticide of H. polyanthemum, both species native to south Brazil. From the hexane extract of Hypericum carinatum we isolated and identificated by spectroscopic methods the phloroglucinol derivative uliginosin B and the benzophenones carifenone A e carifenone B, both restrict to this species until now. The other compounds, isolated in very small amount were not sufficient for the spectroscopic analysis. From the ethyl acetate fraction of this species there were obtained two flavonoids, one of them identified as hyperoside by chromatographic comparison with authentic sample and the other, quercitrin, identified by NMR spectroscopy. In the insecticidal experiments it was used the cotton stainer, Dysdercus peruvianus.Tests performed with the hexane extract demonstrated a potential insecticidal activity since it was observed a tendency of phago-inhibition in concentrations up to 1%. The well established insecticidal activity of benzopyran derivatives as precocene I, precocene II, encecalin and demethylencecalin led us to investigate the activity of the benzopyrans isolated from the above extrac. There were analysed the compounds HP1 (6-isobutyiryl-5,7-dimethoxy-2,2-dimethyilbenzopyran), HP2 (7-hydroxi-6-isobutyryl-5-methoxi-2,2-dimethyl-benzopyran) and HP3 (5-hydroxi-6-isobutyryl-7-methoxi-2,2-dimethyl-benzopyran). Only HP2 presented insecticidal activity at the concentration of 0,2%.
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Pharmaceutical analysis and aspects of the quality control of St. John's Wort productsWild, Tracy Joy January 2003 (has links)
Most complementary medicines contain a multitude of chemical components, some of which are claimed to contribute to the biological activity of such products. Use of complementary medicines for preventative and therapeutic purposes is increasing rapidly worldwide. Unfortunately, although control of these products is essential to ensure quality, safety, and efficacy, the quality control of most herbal preparations is currently poor to non-existent, with little or no safety and efficacy data required to support the marketing and use of these products. The objective of this study was therefore to develop suitable analytical methods to qualitatively and quantitatively analyse the relevant components (rutin, isoquercitrin, hyperoside, quercitrin, quercetin, kaempferol, hypericin, pseudohypericin and hyperforin) in St John's Wort dosage forms for quality control purposes. A gradient HPLC method using a Luna 5·mC₁₈(2) 150 x 2.00mm internal diameter (i.d.) column and UV detection, was developed for the separation of six of the relevant flavonoid compounds in St John's Wort, namely rutin, isoquercitrin, hyperoside, quercitrin, quercetin and kaempferol. The development process involved a systematic investigation of gradient conditions, flow rate, and temperature. This method was subsequently applied to assay selected commercially available St John's Wort products. This system provided the necessary accuracy, precision and reproducibility and was associated with several advantages when compared to using standard bore (4.60 mm i.d.) HPLC columns. The method developed is currently the only known method that separates all six relevant flavonoids in a reasonable run time (less than 20 minutes). It is also one of the few methods that has sufficient separation between rutin, isoquercitrin and hyperoside. A qualitative method for the fingerprinting of flavonoid components was also developed, using capillary electrophoresis (CE). CE is a rapidly growing powerful analytical technique for the separation of charged compounds. Micellar electrokinetic chromatography (MEKC) is a very powerful electrophoretic technique that is capable of selectively resolving both neutral and ionic solutes in a single run. A MEKC method suitable for the separation and determination of various flavonoid constituents used as marker compounds in Hypericum perforatum was developed. Investigations into the effect of pH, ionic strength, applied voltage and capillary dimensions on separation were performed. The optimised method was then applied to qualitatively analyse various St John's Wort products on the market. This method was found to be advantageous in that it was simple, cost-effective, required minimal sample preparation and utilised very small quantities of sample. Due to the vast differences in chemical properties between the various marker and active components in St John's Wort, it was necessary to develop separate analytical methods for the flavonoids and for the other three relevant compounds (hypericin, pseudohypericin and hyperforin). An isocratic HPLC method using a Luna 5·mC₁₈(2) 150 x 2.00mm (i.d.) column and UV detection was developed for the separation of hypericin, pseudohypericin and hyperforin. The development process involved a systematic investigation of buffer molarity, mobile phase composition, pH, flow rate, and temperature. This method was subsequently applied to assay selected commercially available St John's Wort products on the South African market. This system also provided the necessary accuracy, precision and reproducibility, as well as the advantages associated with the use of a narrow bore column as opposed to the use of the more commonly used wider bore columns. This method was validated and used to quantitate these three compounds in various commercial St John's Wort products. By applying this method to liquid chromatography – tandem mass spectrometry (LC-MS-MS), qualitative analyses of the same products was performed to obtain confirmation of the quantitative HPLC results. Mass spectrometry is a powerful detection tool that is more selective and specific than many detection systems used with HPLC. Natural medicines usually constitute a multitude of constituents with much potential interference. In this regard LC-MS-MS is a powerful tool, with its ability to unequivocally identify target analytes regardless of the presence of interferences or complex matrices. ESI-MS-MS was used for the qualitative analysis of the content of the naphthodianthrones and hyperforin in the respective tablet products assayed with HPLC. LC-MS-MS analyses were performed in order to identify the constituents and to verify the specificity of the HPLC method. High inter-product and inter-batch variability was observed for all nine compounds assayed. These quantitative results were confirmed with the respective qualitative analyses. This study confirms the need for strict quality control of herbal medicinal products commercially available to consumers.
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Análise química e taxonômica de espécies de hypericum e avaliação da atividade antiangiogênica / Chemical and taxonomic analysis of Hypericum species and antiangiogenic activityNor, Carolina January 2006 (has links)
A comercialização de fitoterápicos obtidos a partir de extratos de H. perforatum para o tratamento de depressão em diversas partes do mundo despertou o interesse de investigadores no estudo de plantas do gênero Hypericum, tanto acerca da composição química quanto das propriedades biológicas destas espécies. Objetivos: Investigar a constituição química de espécies nativas do gênero Hypericum (H. caprifoliatum, H. polyanthemum, entre outras); realizar um estudo quimiotaxonômico de derivados de floroglucinol em espécies de Hypericum. Avaliar a atividade antiproliferativa de benzopiranos isolados de H. polyanthemum frente a células endoteliais. Métodos: Para o isolamento e análise dos compostos foram utilizadas técnicas cromatográficas (CC, CCD e CLAE). A elucidação estrutural foi realizada a partir de métodos espectrofotométrico (UV), espectroscópico (RMN1H e 13C) e espectrométrico. A relevância taxonômica de derivados de floroglucinol foi verificada a partir de revisão da literatura. A avaliação da atividade antiangiogênica foi efetuada pelas técnicas de sulfo-rodamina B e citometria de fluxo. Resultados e Conclusões: De H. caprifoliatum e H. polyanthemum foram isolados três derivados de floroglucinol diméricos. Estes produtos podem ser considerados marcadores quimiotaxonômicos das seções Brathys e Trigynobrathys do gênero Hypericum, as quais incluem todas as espécies nativas do sul do Brasil. Os flavonóides, quercetina e hiperosídeo foram isolados de H. caprifoliatum. Os três benzopiranos testados (Hp1, Hp2 e Hp3) demonstraram capacidade de inibir o crescimento de células endoteliais de forma dose-dependente. Os compostos Hp2 e Hp3 foram capazes de bloquear fases do ciclo celular. / The use of St. John’s Wort extracts as a phytomedicine to treat depression in several countries around the world has stimulated investigators in order to study the chemical and biological properties of Hypericum species. Purpose: to investigate the chemical composition of native representants of Hypericum genus (H. caprifoliatum, H. polyanthemum, among others), to carry out a chemotaxonomic study about the significance of phloroglucinol derivatives in Hypericum species and to evaluate the antiproliferative activity of three benzopyrans isolated from H. polyanthemum against endothelial cells. Methods: for the isolation and identification of the compounds chromatographic techniques such as TLC, CC and HPLC were employed. The structures were determined through NMR spectroscopy, spectrometry and ultraviolet analyses. In order to study the significance of the phloroglucinol derivatives, data on the occurrence of these compounds was surveyed in the literature. The antiangiogenic activity was performed in both Sulforhodamine B and Flow Cytometry assays. Results and Conclusions: From H. caprifoliatum and H. polyanthemum three phloroglucinol derivatives with a dimeric structure were identified. These group of products could be considered as chemotaxonomic markers from species of the Hypericum genus belonging to the Brathys and Trigynobrathys sections, which include all the native representants. This work also presents the isolation and structural determination of two well known flavonoids, quercetin and hyperoside, from H. caprifoliatum. The three benzopyrans, Hp1, Hp2 and Hp3, showed a dose-dependant cytotoxic activity against endothelial cells. The isomers Hp2 and Hp3 were able to cause modifications on the normal cell cycle.
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Análise química e taxonômica de espécies de hypericum e avaliação da atividade antiangiogênica / Chemical and taxonomic analysis of Hypericum species and antiangiogenic activityNor, Carolina January 2006 (has links)
A comercialização de fitoterápicos obtidos a partir de extratos de H. perforatum para o tratamento de depressão em diversas partes do mundo despertou o interesse de investigadores no estudo de plantas do gênero Hypericum, tanto acerca da composição química quanto das propriedades biológicas destas espécies. Objetivos: Investigar a constituição química de espécies nativas do gênero Hypericum (H. caprifoliatum, H. polyanthemum, entre outras); realizar um estudo quimiotaxonômico de derivados de floroglucinol em espécies de Hypericum. Avaliar a atividade antiproliferativa de benzopiranos isolados de H. polyanthemum frente a células endoteliais. Métodos: Para o isolamento e análise dos compostos foram utilizadas técnicas cromatográficas (CC, CCD e CLAE). A elucidação estrutural foi realizada a partir de métodos espectrofotométrico (UV), espectroscópico (RMN1H e 13C) e espectrométrico. A relevância taxonômica de derivados de floroglucinol foi verificada a partir de revisão da literatura. A avaliação da atividade antiangiogênica foi efetuada pelas técnicas de sulfo-rodamina B e citometria de fluxo. Resultados e Conclusões: De H. caprifoliatum e H. polyanthemum foram isolados três derivados de floroglucinol diméricos. Estes produtos podem ser considerados marcadores quimiotaxonômicos das seções Brathys e Trigynobrathys do gênero Hypericum, as quais incluem todas as espécies nativas do sul do Brasil. Os flavonóides, quercetina e hiperosídeo foram isolados de H. caprifoliatum. Os três benzopiranos testados (Hp1, Hp2 e Hp3) demonstraram capacidade de inibir o crescimento de células endoteliais de forma dose-dependente. Os compostos Hp2 e Hp3 foram capazes de bloquear fases do ciclo celular. / The use of St. John’s Wort extracts as a phytomedicine to treat depression in several countries around the world has stimulated investigators in order to study the chemical and biological properties of Hypericum species. Purpose: to investigate the chemical composition of native representants of Hypericum genus (H. caprifoliatum, H. polyanthemum, among others), to carry out a chemotaxonomic study about the significance of phloroglucinol derivatives in Hypericum species and to evaluate the antiproliferative activity of three benzopyrans isolated from H. polyanthemum against endothelial cells. Methods: for the isolation and identification of the compounds chromatographic techniques such as TLC, CC and HPLC were employed. The structures were determined through NMR spectroscopy, spectrometry and ultraviolet analyses. In order to study the significance of the phloroglucinol derivatives, data on the occurrence of these compounds was surveyed in the literature. The antiangiogenic activity was performed in both Sulforhodamine B and Flow Cytometry assays. Results and Conclusions: From H. caprifoliatum and H. polyanthemum three phloroglucinol derivatives with a dimeric structure were identified. These group of products could be considered as chemotaxonomic markers from species of the Hypericum genus belonging to the Brathys and Trigynobrathys sections, which include all the native representants. This work also presents the isolation and structural determination of two well known flavonoids, quercetin and hyperoside, from H. caprifoliatum. The three benzopyrans, Hp1, Hp2 and Hp3, showed a dose-dependant cytotoxic activity against endothelial cells. The isomers Hp2 and Hp3 were able to cause modifications on the normal cell cycle.
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Análise química e taxonômica de espécies de hypericum e avaliação da atividade antiangiogênica / Chemical and taxonomic analysis of Hypericum species and antiangiogenic activityNor, Carolina January 2006 (has links)
A comercialização de fitoterápicos obtidos a partir de extratos de H. perforatum para o tratamento de depressão em diversas partes do mundo despertou o interesse de investigadores no estudo de plantas do gênero Hypericum, tanto acerca da composição química quanto das propriedades biológicas destas espécies. Objetivos: Investigar a constituição química de espécies nativas do gênero Hypericum (H. caprifoliatum, H. polyanthemum, entre outras); realizar um estudo quimiotaxonômico de derivados de floroglucinol em espécies de Hypericum. Avaliar a atividade antiproliferativa de benzopiranos isolados de H. polyanthemum frente a células endoteliais. Métodos: Para o isolamento e análise dos compostos foram utilizadas técnicas cromatográficas (CC, CCD e CLAE). A elucidação estrutural foi realizada a partir de métodos espectrofotométrico (UV), espectroscópico (RMN1H e 13C) e espectrométrico. A relevância taxonômica de derivados de floroglucinol foi verificada a partir de revisão da literatura. A avaliação da atividade antiangiogênica foi efetuada pelas técnicas de sulfo-rodamina B e citometria de fluxo. Resultados e Conclusões: De H. caprifoliatum e H. polyanthemum foram isolados três derivados de floroglucinol diméricos. Estes produtos podem ser considerados marcadores quimiotaxonômicos das seções Brathys e Trigynobrathys do gênero Hypericum, as quais incluem todas as espécies nativas do sul do Brasil. Os flavonóides, quercetina e hiperosídeo foram isolados de H. caprifoliatum. Os três benzopiranos testados (Hp1, Hp2 e Hp3) demonstraram capacidade de inibir o crescimento de células endoteliais de forma dose-dependente. Os compostos Hp2 e Hp3 foram capazes de bloquear fases do ciclo celular. / The use of St. John’s Wort extracts as a phytomedicine to treat depression in several countries around the world has stimulated investigators in order to study the chemical and biological properties of Hypericum species. Purpose: to investigate the chemical composition of native representants of Hypericum genus (H. caprifoliatum, H. polyanthemum, among others), to carry out a chemotaxonomic study about the significance of phloroglucinol derivatives in Hypericum species and to evaluate the antiproliferative activity of three benzopyrans isolated from H. polyanthemum against endothelial cells. Methods: for the isolation and identification of the compounds chromatographic techniques such as TLC, CC and HPLC were employed. The structures were determined through NMR spectroscopy, spectrometry and ultraviolet analyses. In order to study the significance of the phloroglucinol derivatives, data on the occurrence of these compounds was surveyed in the literature. The antiangiogenic activity was performed in both Sulforhodamine B and Flow Cytometry assays. Results and Conclusions: From H. caprifoliatum and H. polyanthemum three phloroglucinol derivatives with a dimeric structure were identified. These group of products could be considered as chemotaxonomic markers from species of the Hypericum genus belonging to the Brathys and Trigynobrathys sections, which include all the native representants. This work also presents the isolation and structural determination of two well known flavonoids, quercetin and hyperoside, from H. caprifoliatum. The three benzopyrans, Hp1, Hp2 and Hp3, showed a dose-dependant cytotoxic activity against endothelial cells. The isomers Hp2 and Hp3 were able to cause modifications on the normal cell cycle.
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