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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Ecofisiologia química de espécies nativas de dois biomas do estado do Paraná / Chemical Ecophysiology of two native species of biomes of the state of Paraná

Pilatti, Daiane Maria 17 September 2012 (has links)
Made available in DSpace on 2017-07-10T14:38:22Z (GMT). No. of bitstreams: 1 Daiane Pilatti.pdf: 1850290 bytes, checksum: 618af49a9d02126676712eced8763a0c (MD5) Previous issue date: 2012-09-17 / Allelopathy is an ecological phenomenon defined as the chemical, positive or negative interference of compounds produced by plants on growth and development of other plants. This phenomenon can modify the structure of plant communities, significantly influencing processes such as ecological succession and species dominance. However, the production of compounds is often affected by environmental conditions, and the allelopathic response of the same species can be differentiated depending on the habitat that is. Thus, the objective of this study was to assess whether different forest types within the State of Paraná can influence the allelopathic effect of native plant species recommended for restoration. The plant species were collected from two forest types: semideciduous forest and Tropical Rainforest. Representing the group of pioneer species were collected J. micrantha, C. and M. pachystachya bimucronata; The group was composed of secondary species by species S. terebinthifolius and C. fissilis; climax species was chosen as the E. edulis. The chemical composition of the collected individuals and allelopathy on germination and early development of pioneer species in secondary and climax species, and secondary, in the climax species, simulating the ecological succession that occurs in the field was analyzed. Species showed differences in the concentration of allelopathic compounds, but the species S. terebinthifolius was the only one to present qualitative difference between chemical compounds. It was found that these species may show differences in potential allelopathic effect and, depending on the forest type in which they were collected, mainly as to speed germination and seedling height field. Finally, the collected species in semideciduous forest were more chemically aggressive than the same species collected in Dense Forest, within the State of Paraná / A alelopatia é um fenômeno ecológico definido como a interferência química, positiva ou negativa, de compostos produzidos pelas plantas sobre o crescimento e desenvolvimento de outras plantas. Este fenômeno pode modificar a estrutura de comunidades vegetais, influenciando significativamente processos como sucessão ecológica e dominância de espécies. Porém, a produção dos compostos é frequentemente afetada por condições ambientais, e a resposta alelopática de uma mesma espécie pode ser diferenciada dependendo da habitat que se encontra. Desta forma, o objetivo deste trabalho foi avaliar se diferentes formações florestais dentro do Estado do Paraná podem influenciar o efeito alelopático de espécies nativas recomendadas para restauração vegetal. As espécies vegetais foram coletadas em duas formações florestais: Floresta Estacional Semidecidual e Floresta Ombrófila Densa. Representando o grupo das espécies pioneiras foram coletadas J. micrantha, C. pachystachya e M. bimucronata; o grupo de espécies secundárias foi composto pelas espécies S. terebinthifolius e C. fissilis; como espécie clímax foi escolhido o E. edulis. Foi analisada a composição química dos indivíduos coletados e a alelopatia na germinação e desenvolvimento inicial das espécies pioneiras sob as espécies secundárias e clímax, e das secundárias, sob a espécie clímax, simulando a sucessão ecológica que ocorre em campo. As espécies apresentaram diferença na concentração dos compostos alelopáticos, mas foi a espécie S. terebinthifolius a única a apresentar diferença qualitativa entre os compostos químicos. Constatou-se que as espécies estudadas podem apresentar diferença no potencial e efeito alelopático, dependendo da formação florestal em que foram coletadas, principalmente quanto à velocidade na germinação e altura das mudas em campo. Por fim, as espécies coletadas na Floresta Estacional Semidecidual foram mais quimicamente agressivas do que as mesmas espécies coletadas na Floresta Ombrófila Densa, dentro do Estado do Paraná.
62

Études phytochimiques de plantes médicinales djiboutiennes à effets antimicrobiens et anticancéreux / Phytochemical study of medicinal plant from Djibouti with antimicrobial and anticancer effects

Elmi Fourreh, Abdirahman 30 November 2018 (has links)
Ce travail a porté sur la bio-analyse de plantes médicinales Djiboutiennes. Ces dernières ont été sélectionnées sur des critères ethnobotaniques appliqués sur les plantes utilisées traditionnellement contre les infections microbiennes. Cette sélection a retenu six plantes qui ont ensuite subi un screening antibactérien et anti oxydant. Les résultats de ce screening ont conduit à étudier trois plantes: Acacia seyal, Indigofera caerulea et Cymbopogon commutatus. La recherche des composés de l’Acacia seyal est effectuée au moyen d’un bio-guidage. Deux extraits, aqueux et méthanolique, de l’écorce de cette plante sont évalués pour leur activité antibactérienne. Quatre composés sont isolés et caractérisés (épicatéchine, catéchine, catéchine digallique et β-sitostérol) et testés pour leurs activités. Par ailleurs quatre extraits (hexanique, acétonique, méthanolique et aqueux) du fruit d’Indigofera caerulea ont été testés pour leurs activités antibactérienne et anti oxydante. Les extraits hexanique et méthanolique sont les plus actifs. Six composés sont isolés de ces extraits (méthyl gallate, acide gallique, rutine, isoquercétine, kaempférol-3- rutinoside et β-sitostérol). Le méthyl gallate inhibe staphylococcus aureus avec une CMI de 64 µg/ mL. Enfin l’activité de l’huile essentielle de Cymbopogon commutatus est testée sur sept souches bactériennes, deux souches fongiques et onze types de cellules cancéreuses. Sur ces dernières, elle présente une forte cytotoxicité avec des IC50 allant de 0,05 µg/mL sur PC3 et HCT116 (cellules cancéreuses de la prostate et colorectales) et à 0,67 µg/mL sur NCI-N87 (cellule cancéreuse gastrique). De façon surprenante, une activité antibactérienne moyenne est observée. L’analyse GCMS de la partie solubilisée dans le milieu de culture a montré que seuls les composés hydrophiles étaient présents. La formulation d’une micro émulsion a été mise au point et les IC50 ont diminué jusqu’à une centaine de fois. Nous avons montré que cette huile essentielle renferme plus de 73,9 % de pipéritone (monoterpène). En conclusion, ces trois plantes ont montré des activités antimicrobiennes, et les travaux confirment leurs utilisations traditionnelles. En plus, nous avons montré qu’elles possèdent d’autres activités biologiques (anti oxydante et anti cancéreuse). Ces résultats devront contribuer à la mise en place d’une pharmacopée traditionnelle et à des formulations de ‘médicaments traditionnels améliorés’ (MTA) / This research focused on the bio-analysis of Djiboutian medicinal plants. These latter were selected on ethnobotanical criteria applied to the plants traditionally used against microbial infections. This selection retained six plants which were then subjected to a biological screening including antibacterial and anti-oxidant activities. Three plants were finally study: Acacia seyal, Indigofera caerulea and Cymbopogon commutatus. The search of compound in Acacia seyal was carried out by means of bio-guidance. Two extracts, aqueous and methanolic, of the bark of this plant were evaluated for their antibacterial activity. Four compounds were isolated, characterized (epicatechin, catechin, digallic catechin and β-sitosterol) and tested for their activity. Also four extracts (hexanic, acetonic, methanolic and aqueous) of the fruit of Indigofera caerulea were tested for their antibacterial and antioxidant activities. The Hexanic and methanolic extracts were the most active. Six compounds were isolated from these extracts (methyl gallate, gallic acid, rutin, isoquercetin, kaempferol-3-rutinoside and β-sitosterol). Methyl gallate inhibited Staphylococcus aureus with a MIC of 64 μg / mL. Finally, the activity of the essential oil of Cymbopogon commutatus was evaluated on seven bacterial strains, two fungal strains and eleven types of cancer cells. On the latter, it exhibits a high cytotoxicity with IC50s ranging from 0.05 μg / mL on PC3 and HCT116 (prostate and colorectal cancer cells) to 0.67 μg/mL on NCI-N87 (gastric cancer cell). Surprisingly, an antibacterial activity not so high was observed. GCMS analysis of the solubilized part in the culture medium showed that only the hydrophilic compounds were present. The formulation of a microemulsion was performed and the IC50 decreased to a hundred times. We have found that this essential oil contained more than 73.9 % piperitone (monoterpene). In conclusion, these three plants showed antimicrobial activities and the work confirms their traditional uses. In addition, we have shown that they have other biological activities (anti-oxidant and anti-cancer). These results should contribute to the establishment of a traditional pharmacopoeia and formulations of 'improved traditional medicines' (MTAs)
63

Phytochimie et propriétés biologiques d'extraits de plantes antidiabétiques utilisées au Bénin

Bothon, Fifa 22 September 2012 (has links)
Le présent travail rend compte des études phytochimiques et biologiques d'extraits non volatils de quatre plantes utilisées au Bénin dans le traitement du diabète. La première partie passe en revue la bibliographie sur les plantes sujettes à notre étude. Dans cette partie, la systématique, l'importance en pharmacopée ainsi que les travaux déjà effectués sur ces plantes ont été présentés. La deuxième partie présente le mode d'extraction et les études chimiques des extraits et les résultats obtenus. La spectrophotométrie a permis de déterminer quelques grandes familles de composés présents dans les extraits : les polyphénols totaux, les flavonoïdes et les tanins tandis que la GC/MS et la LC/MS ont servi à mettre en exergue la présence de composés volatils et non volatils. La troisième partie décrit les tests biologiques in vitro et ex vitro effectués sur les extraits. Les extraits ont montré de manière générale des activités : inhibitrice de l' α-glucosidase, antioxydantes (DPPH, FRAP, ORAC), antimicrobiennes et l'une (Bridelia ferruginea) une activité cytotoxique sur les cellules cancéreuses (PA1, MCF7, PC3, DU-145), avec une efficacité variable d'une plante à une autre. La quatrième partie discute de manière générale des résultats issus des études phytochimiques et des tests biologiques. Parmi les quatre échantillons de plantes sélectionnées pour notre étude, seul l'extrait semi-éthanolique des racines de Ceiba pentandra a une faible teneur en familles de composés dosés et présente des activités biologiques (ci-dessus citées) faibles comparativement aux extraits de Bridelia ferruginea, de Pseudocedrela kotschyi et de Polygonum senegalensis. L'ensemble des résultats tant sur le plan chimique que biologique met en évidence les potentialités des extraits de plantes étudiées, pour une exploitation à des fins thérapeutiquesfutures. / The present work had reported on the phytochemical and biological studies of non-volatile extracts of four plants used in Benin for diabetes treatment. The first part reviewed the bibliography of investigated plants in our study. In this part, the systematic, the importance in the pharmacopoeia and the previous works done on these plants were presented. The second part has presented the extraction method and chemical studies of the extracts and results obtained. The spectrophotometry has permitted to identify some important families of compounds in the extracts: the total polyphenols, flavonoids and tannins whereas the GC / MS and LC/MS were used to highlight the presence of volatile and non-volatile compounds. The third part described the biological tests in vitro and ex vitro carried out on the extracts. The extracts showed in general activities: α-glucosidase inhibition, antioxidant (DPPH, FRAP, ORAC), antimicrobial, and one of them (Bridelia ferruginea) were cytotoxic on cancer cells (PA1, MCF7, PC3, DU-145), with a variable efficiency from one plant to another. The fourth part had discussed in general about the results obtained from phytochemical studies and biological tests. Among the four plants samples selected for our study, only the semi-alcoholic extract of Ceiba pentandra roots had a low-dosed compounds families and presented of this biological activities (cited below) low comparatively to Bridelia ferruginea, Pseudocedrela kotschyi and Polygonum senegalensis extracts. Both of the chemical and biological results highlight the potential of certain species for future exploitation of their non-volatile extract for therapeutic purposes.
64

Fungal endophytes enhance growth and production of natural products in Echinacea purpurea (Moench.)

Gualandi, Richard James, Jr. 01 August 2010 (has links)
Echinacea purpurea is a native herbaceous perennial with substantial economic value for its medicinal and ornamental qualities. Arbuscular mycorrhizae are symbiotic fungi that form relationships with plant roots and are known to enhance growth in the host. Mycorrhizae and other fungal endophytes often affect stress resistance and secondary metabolism in the host, as well as the ecology of other endophytes in the plant. A newly emerging paradigm in sustainable biotechnique is the targeted use of fungal endophytes to enhance growth and secondary metabolism in crops. Many of the therapeutic compounds in E. purpurea could be affected by fungal colonization. In this research the effects of inoculation of Echinacea purpurea with two classes of fungal endophytes: the arbuscular mycorrhizal fungi Glomus intraradices and Gigaspora margarita and the entomopathogenic endophyte Beauveria bassiana were evaluated . Endophyte colonization and impacts on plant growth and phytochemistry were tested in multiple greenhouse experiments. Arbuscular mycorrhizae and B. bassiana effectively colonized E. purpurea with some significant interactive effects. Consistent, substantial, and significant increases in all growth parameters were observed in mycorrhizal plants; mycorrhizal plants produced up to four times the biomass of controls in 12 weeks. Broad spectrum changes in fertilization were necessary to produce mycorrhizal and nonmycorrhizal samples of equal size, and severely nutrient-limited mycorrhizal E. purpurea seedlings maintained growth rates comparable to well fertilized samples. Treatment with B. bassiana had minor and inconsistent effects on some plant growth parameters, and there were significant interactive effects with arbuscular mycorrhizae. Phytochemical concentrations in all metabolite classes tested responded significantly to inoculation with both classes of fungal endophytes. Changes were observed in various pigments, caffeic acid derivatives, alkylamides, and terpenes. Many of the affected compounds have important roles in metabolism or have bioactive value as natural products. When considered from a net production perspective (concentration X dry weight), compared to controls, plants inoculated with endophytes produced as much as 30 times the content of some compounds in 12 weeks. This work effectively demonstrates that fungal endophytes can enhance the bioactivity of plant tissues and the production of natural products in E. purpurea.
65

Chemical and biological investigation into some selected African indigenous medicinal plants

Jelili Olalekan Babajide January 2009 (has links)
<p>African medicinal plants are commonly used throughout Africa to treat a variety of ailments including wounds and ulcers, cough and chest complaints, gingivitis, fever and gonorrhoea, indication all related to infection and inflammation. In screening several plant species from an inventory of common medicinal plants from both South and West Africa for diverse medicinal purposes, 6 plants were selected because of their interesting and useful ethnomedicinal values.</p>
66

Identification And Characterization Of Hydrolytic Enzymes Of Sunn Pest (eurygaster Integriceps) And Cotton Bollworm (helicoverpa Armigera)

Ozgur, Ebru 01 September 2006 (has links) (PDF)
In this study, hydrolytic enzymes from sunn pest (Eurygaster integriceps) and cotton bollworm (Helicoverpa armigera) midguts were identified and characterized in terms of their optimum pH, Km and Vmax values. Hydrolytic activities were also tested for inhibition by several protease and alpha-amylase inhibitors which can be used for the development of insect resistant plants through transgenic technologies. For sunn pest midgut, a low proteolytic activity, belonging mostly to trypsin-like and leucine aminopeptidase-like proteases, and a very high alpha-amylase activity was found in sunn pest midgut, reflecting its high carbohydrate diet. Proteolytic activities could not be inhibited by natural protease inhibitors (SBTI and aprotinin) but inhibited significantly by a general serine protease inhibitor PMSF and metalloprotease inhibitors CdCl2 and CuCl2. alpha-Amylase activity of sunn pest midgut is resistant to inhibition by bean alpha-amylase inhibitor, but inhibited by chickpea, wheat and maize alpha-amylase inhibitors by 26 %, 37 % and 40 %, respectively. For cotton bollworm midgut, a very high proteolytic activity, belonging to serine and metalloprotease type, was detected. alpha-Amylase activity was lower compared to sunn pest midgut, but there were higher and diverse type of proteases, might be reflecting its wide range of host preference. Proteolytic activity was significantly inhibited by both natural protease inhibitors (SBTI and aprotinin). It was also inhibited by several synthetic protease inhibitors (PMSF, E-64, TPCK, CdCl2, CuCl2, Chymostatin). alpha-Amylase activity was inhibited by 60 % by wheat alpha-amylase inhibitor, while maize, chickpea and bean alpha-amylase inhibitors had no effect on cotton bollworm midgut alpha-amylase activity.
67

Fungal endophytes enhance growth and production of natural products in Echinacea purpurea (Moench.)

Gualandi, Richard James 01 August 2010 (has links)
Echinacea purpurea is a native herbaceous perennial with substantial economic value for its medicinal and ornamental qualities. Arbuscular mycorrhizae are symbiotic fungi that form relationships with plant roots and are known to enhance growth in the host. Mycorrhizae and other fungal endophytes often affect stress resistance and secondary metabolism in the host, as well as the ecology of other endophytes in the plant. A newly emerging paradigm in sustainable biotechnique is the targeted use of fungal endophytes to enhance growth and secondary metabolism in crops. Many of the therapeutic compounds in E. purpurea could be affected by fungal colonization. In this research the effects of inoculation of Echinacea purpurea with two classes of fungal endophytes: the arbuscular mycorrhizal fungi Glomus intraradices and Gigaspora margarita and the entomopathogenic endophyte Beauveria bassiana were evaluated . Endophyte colonization and impacts on plant growth and phytochemistry were tested in multiple greenhouse experiments. Arbuscular mycorrhizae and B. bassiana effectively colonized E. purpurea with some significant interactive effects. Consistent, substantial, and significant increases in all growth parameters were observed in mycorrhizal plants; mycorrhizal plants produced up to four times the biomass of controls in 12 weeks. Broad spectrum changes in fertilization were necessary to produce mycorrhizal and nonmycorrhizal samples of equal size, and severely nutrient-limited mycorrhizal E. purpurea seedlings maintained growth rates comparable to well fertilized samples. Treatment with B. bassiana had minor and inconsistent effects on some plant growth parameters, and there were significant interactive effects with arbuscular mycorrhizae. Phytochemical concentrations in all metabolite classes tested responded significantly to inoculation with both classes of fungal endophytes. Changes were observed in various pigments, caffeic acid derivatives, alkylamides, and terpenes. Many of the affected compounds have important roles in metabolism or have bioactive value as natural products. When considered from a net production perspective (concentration X dry weight), compared to controls, plants inoculated with endophytes produced as much as 30 times the content of some compounds in 12 weeks. This work effectively demonstrates that fungal endophytes can enhance the bioactivity of plant tissues and the production of natural products in E. purpurea.
68

Chemical and biological investigation into some selected African indigenous medicinal plants

Jelili Olalekan Babajide January 2009 (has links)
<p>African medicinal plants are commonly used throughout Africa to treat a variety of ailments including wounds and ulcers, cough and chest complaints, gingivitis, fever and gonorrhoea, indication all related to infection and inflammation. In screening several plant species from an inventory of common medicinal plants from both South and West Africa for diverse medicinal purposes, 6 plants were selected because of their interesting and useful ethnomedicinal values.</p>
69

Perfil fitoquímico e avaliação dos principais efeitos biológicos e imunológicos In Vitro da Euphorbia tirucalli L. / PHYTOCHEMISTRY PROFILE AND EVALUATION OF THE PRINCIPALS BIOLOGICAL AND IMMUNOLOGICAL IN VITRO EFFECTS OF Euphorbia tirucalli L.

Machado, Michel Mansur 12 December 2007 (has links)
Today we can easily find the most diverse kind of information about a particular medicinal plant, but without scientific basis, making their use a potential risk to health. Overall, the findings on the safety and efficacy are based on precarious evaluations and popular use. There is a need for qualified professionals to access, critical analyze and assign such information in a way that it could be easily understood, not only by health professionals, but also by the users of these products. One example of these plants used in popular medicine, but without scientific evidence, is Euphorbia tirucalli L., popularly known as Dog-Stick, Pencil tree, or more commonly as Aveloz. This plant has been used for the treatment of many diseases, such as microbial diseases, immunossupression problems, and even in the cancer treatment. However, some works reveal precisely the opposite, namely that the latex of Euphorbia tirucalli can cause immunosuppression, and often is associated to the appearance of Burkitt's Lymphoma, a type of cancer. Lupeol was isolated and identificated from hexane fraction by GC-MS for the first time for the plant, among other 3 hydrocarbons, 7 long chain fat acids, 2 steroids, and 3 compounds of the vegetal metabolism. A preliminary phytochemistry screening allowed to the visualization of the principal groups in the plant. Polyphenols and condensed tannins contents were determined in the crude extract and fractions. Ethyl ether and ethyl acetate fractions showed the greatest antioxidant activity in the DPPH test. Antimicrobial activity was observed mainly against Candida albicans, Candida glabrata and Saccharomyces cereviseae, as well as for the opportunist algae Prototheca zopfii. A preliminary study of toxicity using Artemia saline and acute oral toxicity in mice, indicate the plant as low toxicity. The latex of the E. tirucalli, even in small doses (1%) can cause in vitro inhibition over the human Acetylcholinesterase enzyme. A prominent in vitro inhibitory activity over human platelets aggregation was also observed. The effects of the extract of the plant over the blood cells in a culture medium using ex-vivo blood samples of male Wistar rats were evaluated. The results demonstrated that the extract caused thrombocytopenia, leucopenia and lymphopenia. / Atualmente podemos encontrar facilmente as mais diversas informações sobre uma determinada planta medicinal, mas que carecem de fundamento científico, tornando assim seu uso um potencial risco a saúde. Em geral, as conclusões sobre segurança e eficácia são baseadas em avaliações precárias do uso popular. Portanto, há necessidade de que profissionais qualificados possam, além de acessar tais informações, analisá-las criticamente para disponibilizá-las de forma que sejam facilmente compreendidas, não só por profissionais da saúde, mas também pelos usuários destes produtos. Um exemplo destas plantas utilizadas na medicina popular, mas sem comprovação científica, é a Euphorbia tirucalli L., conhecida popularmente como Graveto-do-cão, Árvore Lápis, ou mais comumente como Aveloz. Esta planta tem sido utilizada para o tratamento de inúmeras enfermidades, como afecções microbianas, problemas de imunossupressão, cicatrização de berrugas e até mesmo no tratamento do câncer. Entretanto, alguns trabalhos revelam justamente o contrário, ou seja, que o látex da Euphorbia tirucalli pode causar imunossupressão, e freqüentemente encontra-se associado ao aparecimento do Linfoma de Burkitt, que é um tipo de câncer. Foram isolados e identificados por cromatografia gasosa acoplada a espectrometria de massas, 03 hidrocarbonetos, 07 ácidos graxos de cadeia longa, 02 esteróides, 03 compostos do metabolismo vegetal e 01 triterpeno, não relatado até o momento, o qual foi isolado da fração hexânica e identificado como sendo o lupeol. Foi realizada uma análise fitoquímica preliminar, o que permitiu a visualização dos grupos de compostos presentes na planta. A quantidade de polifenóis e taninos condensados foi determinada na planta e suas frações. Realizou-se o teste de atividade antioxidante e com ele verificamos uma excelente atividade das frações éter etílico e acetato de etila. Analisou-se a atividade antimicrobiana da planta e obtivemos resultados excelentes para os fungos Candida albicans, Candida glabrata e Saccharomyces cereviseae, bem como para a alga oportunista Prototheca zopfii. Realizou-se um estudo de toxicidade sobre a Artemia salina e estudo de toxicidade oral aguda. Os resultados apontam a espécie como sendo não tóxica. O látex da E. tirucalli, mesmo em doses pequenas (1%) pode causar inibição (in vitro) a enzima Acetilcolinesterase Humana. Uma acentuada atividade inibitória sobre a agregação plaquetária foi observada. O extrato da planta sobre cultura de células sanguíneas de ratos Wistar (exvivo) causou diminuição do número de leucocitos, linfócito e plaquetas.
70

Estudo fitoquímico e farmacobotânico de Richardia brasiliensis Gomes (Rubiaceae) / Phytochemistry and Pharmacobotanical Study of Richardia brasiliensis Gomes (Rubiaceae)

Souza, Fábio Henrique Tenório de 13 November 2009 (has links)
Made available in DSpace on 2015-05-14T12:59:45Z (GMT). No. of bitstreams: 1 parte1.pdf: 1844799 bytes, checksum: c45c18425ecd99744a816e6d2e894e3f (MD5) Previous issue date: 2009-11-13 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Richardia brasiliensis Gomes (Rubiaceae), a herbaceous plant known as "ervanço", "poaia" and "ipeca", is popularly used as emetic, anti-diabetic, worms and the treatment of eczema, burns, bronchitis, influenza, hemorrhoids and avian malaria. Pharmacological studies have shown antimicrobial and antioxidant activity and phytochemical previous investigations resulted in the isolation of terpenoids, flavonoids and coumarin. This study aimed to contribute to the knowledge of the Richardia genus and Rubiaceae family through the phytochemical and pharmacobotanical study of Richardia brasiliensis Gomes. For this, the plant material was collected in João Pessoa - Paraíba and deposited in the Herbarium Prof. Lauro Pires Xavier (JPB) with the code Tenorio-Souza 01. In the pharmacobotanical study, the external morphology of the plant was to the naked eye and with a stereomicroscope. The microscopical morphodiagnosis were performed paradermic and transverse sections of leaves (blade and petiole), as well as transverse sections of stems and roots, which were cleared, stained, mounted between slide and coverslip and examined under the light microscope. The macroscopic anatomy of all organs revealed aspects that are common to species belonging to the family Rubiaceae, such as simple opposite leaves, interpetiolar stipules, flowering tops, flowers bisexual and actinomorphic, aestivation valve and inferior ovary. Microscopically, the leaf presents presenting the upper and lower epidermis, stomata and simple trichomes. The main vein has collateral vascular bundle. The petiole has vascular bundle arc-shaped and four small lateral bundles. In cross section, the stem secondary growth is cylindrical and the vascular system provides continuous siphonostele ectophloic organization, already has a tap root cortical parenchyma with idioblasts containing raphides and system with vascular bundle organization protostele in lateral roots and protostele radiated in the main root. For phytochemical study, vegetable, dried and pulverized, was subjected to extraction processes, and partition chromatography to isolate the chemical constituents. The chemical structure has been assessed by spectroscopic methods such as IR, Mass and uni-dimensional 1H and 13C NMR and comparisons with literature data. The hexane phase was obtained a mixture of steroids (β-sitosterol and stigmasterol) and 151-hydroxy-(151- S)- porfirinolactone a; CHCl3 phase was isolated and identified four coumarins: cedrelopsin, norbraylin, braylin and 5,6 -dimethoxy-7,8-[2'-(prop-1-en-2-yl)-(2'-S)- 2',3'-dihydrofuran]coumarin (cumarineletefin), the latter being first reported the literature, and the AcOEt phase was obtained the flavonoid kaempferol, contributing therefore to the chemotaxonomy of the Richardia genus and Rubiaceae family. / Richardia brasiliensis Gomes (Rubiaceae), planta herbácea conhecida por ervanço , poaia e ipeca , é utilizada popularmente como emética, antidiabética, vermífuga e no tratamento de eczema, queimadura, bronquite, gripe, hemorróida e malária avícola. Estudos farmacológicos revelaram atividade antimicrobiana e antioxidante e investigações fitoquímicas anteriores resultaram no isolamento de terpenóides, flavonóide e cumarina. Este trabalho objetivou contribuir para o conhecimento do gênero Richardia e da família Rubiaceae por meio do estudo farmacobotânico e fitoquímico de Richardia brasiliensis Gomes. Para isto, o material vegetal foi coletado em João Pessoa Paraíba e depositado no Herbário Prof. Lauro Pires Xavier (JPB) com o código Tenório-Souza 01. No estudo farmacobotânico, a morfologia externa do vegetal foi analisada à vista desarmada e com auxílio de estereomicroscópio. Para as morfodiagnoses microscópicas, foram realizados secções paradérmicas e transversais das folhas (lâmina e pecíolo), bem como, secções transversais do caule e das raízes, que foram clarificadas, coradas, montadas entre lâmina e lamínula e analisadas ao microscópio óptico comum. A caracterização macroscópica de todos os órgãos evidenciou aspectos que são comuns às espécies pertencentes à família Rubiaceae, tais como, folhas simples opostas, estípulas interpeciolares, inflorescência cimosa, flores bissexuadas e actinomorfas, prefloração valvar e ovário ínfero. Microscopicamente, a folha é anfiestomática apresentando nas epidermes superior e inferior, estômatos paracíticos e tricomas tectores simples. A nervura principal apresenta feixe vascular colateral. O pecíolo possui feixe vascular em forma de arco e quatro pequenos feixes vasculares laterais. Em secção transversal, o caule em crescimento secundário é cilíndrico e o sistema vascular apresenta organização sifonostélica contínua ectoflóica, já a raiz principal apresenta parênquima cortical com idioblastos contendo ráfides e sistema vascular anficrival com organização protostélica nas raízes laterais e protostélica radiada na raiz principal. Para o estudo fitoquímico, o vegetal, após secagem e pulverização, foi submetido a processos de extração, partição e cromatografia para isolamento dos constituintes químicos. A estrutura química dos mesmos foi determinada por métodos espectroscópicos, tais como: Infravermelho, Massas e Ressonância Magnética Nuclear de 1H e 13C uni e bidimensionais e comparações com modelos da literatura. Da fase hexânica obtevese uma mistura de esteróides (β-sitosterol e estigmasterol) e 151-hidroxi-(151-S)- porfirinolactona a; da fase CHCl3 foi isolado e identificado quatro cumarinas: cedrelopsina, norbraylina, braylina e 5,6-dimetoxi-7,8-[2 -(prop-1-en-2-il)-(2 -S)-2 ,3 - diidrofurano]cumarina (cumarineletefina), sendo esta última relatada pela primeira vez na literatura; e da fase AcOEt obteve-se o flavonóide canferol, contribuindo, portanto para a quimiotaxonomia do gênero Richardia e da família Rubiaceae.

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