18 resultados para Tabernaemontana hilariana


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This paper reports the separation of the indole alkaloids from the benzene extract of the root barks of Tabernaemontana hilariana (Apocynaceae). The crude alkaloid fraction was fractionated by droplet counter-current chromatography using a low polarity mixture (hexane:ethyl acetate:ethanol:water). Nine indole alkaloids (3-hydroxycoronaridine, coronaridine, voacangine, 3-(2-oxopropyl) coronaridine, voacangine hydroxyindolenine, ibogamine, voacangine pseudoindoxyl, coronaridine pseudoindoxyl and tabernanthine) were identified using thin laver chromatography gas chromatography coupled with mass spectrometry and nuclear magnetic resonance spectroscopy. Copyright (C) 1999 John Wiley & Sons, Ltd.

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This paper reports the separation and identification of indole alkaloids, steroids and triterpenoids from the ethanolic extracts of Tabernaemontana hilariana (Apocynaceae). The alkaloidal fractions from the ethanolic extracts obtained (root barks, green fruits, ripe fruits and seeds) were fractionated and analysed by thin-layer chromatography, capillary gas chromatography-flame ionization detection (cGC-FID) as well as by high-resolution gas chromatography-mass spectrometry (HRGC-MS). 3-Hydroxycoronaridine, ibogamine, coronaridine pseudoindoxyl, coronaridine, catharanthine, voacangine hydroxyindolenine, voacangine pseudoindoxyl, tabernanthine, tetraphyllicine, 3-hydroxyvoacangine, voacangine, isovoacangine and 3-oxocoronaridine were identified. The insoluble fraction of ethanolic extracts obtained from the root barks and green fruits were analysed and ten aliphatic constituents were also identified by cGC-FID and HRGC-MS. (C) 1998 Elsevier B.V. B.V. All rights reserved.

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A fast and efficient procedure was elaborated to identify the alkaloid constituents from Tabernaemontana hilariana (Apocynaceae). The strategy based on fractioning of the crude alkaloid fraction in small silica cartridges followed by thin-layer chromatography (TLC), capillary gas chromatography-flame ionization detection as well as high-resolution gas chromatography-mass spectrometry afforded voacangine, coronaridine, ibogamine, voacangine pseudoindoxyl, voacangine hydroxyindolenine, 3-hydroxycoronaridine and 3-(2-oxopropyl)coronaridine. (C) 1997 Elsevier B.V. B.V.

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Partial neutralization of the myotoxic effect of Bothrops jararacussu venom (BV) and two of its myotoxins [bothropstoxin-I (BthTX-I), catalytically inactive, and II (BthTX-II), showing low PLA(2) activity], by the lyophilized aqueous extract of Tabernaemontana catharinensis (AE), was studied in rat isolated soleus muscle preparations (in vitro) and through i.m. injection in the gastrocnemius muscle (in vivo) by determination of creatine kinase (CK) activity and histopathological analysis. Incubation of soleus muscle for 1 h with BV or toxins (20 mug/ml) plus AE (400 mug/ml) added immediately after BV, BthTX-I or BthTX-II reduced CK levels by 53%, 37% and 56%, respectively. The myonecrotic effects of BV (20 mug/ml) upon soleus muscle was reduced 24%, 35% and 36% when AE (400 mug/ml) was added 1 h after BV and CK was evaluated 30 min, 1 and 2 h later, respectively. For BthTX-I these values were 46%, 48% and 47%, while for BthTX-II no inhibitory effect was detected. Histological analysis of soleus muscle after incubation with AE (400 mug/ml, I h) did not reveal any change in muscle fibers, but severe necrosis induced by -BV or toxins (20 mug/ml) was clearly in evidence, and decreased significantly when soleus muscle was protected by AE. This protection was also observed when AE was administered 1 h after BV or BthTX-I, but not after BthTX-II. AE did not inhibit the catalytic PLA(2), activity of BthTX-II or BV and did not change the PAGE pattern of BV, BthTX-I or BthTX-II. In vivo assays were performed in 100-g rats and maximal CK release was attained at a dose of 100 mug of BV, 3 h after injection. AE was not effective when injected 20 s after BV or toxins. However, injecting BV or toxins (100 mug), which were pre-incubated with AE (2 mg) caused an inhibition of 57%, 59% and 51%, respectively, with zero time pre-incubation, but was less effective with I h pre-incubation. This plant represents a potential source of promising myotoxin inhibitors. (C) 2004 Elsevier GmbH. All rights reserved.

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"Isolation and evaluation of the biological activity related to the major alkaloids in Tabernaemontana angulata Mart. ex Mull Arg., Apocynaceae." Introducing-new chemotherapeutic agents is a, great demand. in the control of infections diseases.' Brazil is one of the richest countries in biodiversity and the Laboratorio de Extracao at UNIP has been collecting plants from. the Amazon and Atlantic Rain Forests with the aim of screening for new antibacterial and antitumor plant extracts. Previous studies demonstrated that the ethanol fraction obtained from the crude extract of Tabernaemontana angulata stems showed antibacterial activity against Staphylococcus aureus (ATCC 6538 in the microdilution broth assay. Two alkaloids were the major compounds in the active fraction, verified by thin layer chromatography analysis. In the present study, the total alkaloids were obtained from the crude extract and were fractionated by preparative thin layer chromatography for the isolation of the main components. The isolated. compounds were identified by GC/MS and (1)H-NMR as coronaridine,e and voacangine. The alkaloid fractions obtained from the isolation procedure were tested for antibacterial activity, but no activity was detected.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Tabernaemontana fuchsiaefolia A. DC é uma espécie da família Apocynaceae, nativa do Brasil, com característica invasora, possuindo potencial para uso em recuperação de áreas degradadas. O trabalho teve o objetivo de avaliar a influência dos métodos de envelhecimento acelerado sobre a qualidade fisiológica e germinação de sementes, utilizando-se o método tradicional e em solução de NaCl, empregando-se a metodologia de gerbox, formando minicâmaras de envelhecimento, em três temperaturas (41, 43 e 45°C) e cinco tempos de envelhecimento (0, 24, 48, 72 e 96 horas). As sementes, após o envelhecimento, foram colocadas para germinar em rolos de papel germitest, em quatro repetições de 25 sementes, em câmaras BOD a temperatura de 30°C, com fotoperíodo de 8 horas. O efeito da temperatura foi comparado pelo teste de Tukey em nível de 5% de probabilidade e o efeito do tempo de envelhecimento, pela análise de regressão. Após 35 dias, foram avaliados percentual, índice de velocidade, tempo médio e frequência da germinação, bem como comprimento de raiz e parte aérea, massa seca de plântulas e percentual de plântulas normais. Observou-se que o método alternativo de envelhecimento com solução de NaCl teve pouca influência na qualidade das sementes, não sendo indicado para testes de vigor para a espécie. O método tradicional, na temperatura de 45°C em período de envelhecimento de 96 horas, promoveu queda na germinação e pode ser utilizado para testar o vigor de sementes de leiteira.

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Ethnopharmacological relevance: Traditional remedies used for treating diabetic ailments are very important in the primary health care of the people living in rural Dhemaji district of Assam, north-east India. Novel information gathered from the current survey is important in preserving folk indigenous knowledge. Materials and methods: Interviews were conducted amongst 80 households comprising of 240 individuals using semi-structured questionnaires. The focus was on plants used in treating diabetes mellitus. Results: The current survey documented 21 plant species (20 families) which are reportedly used to treat diabetes mellitus by the rural people in the study area. To the best of our knowledge, Amomum linguiforme, Cinnamomum impressinervium, Colocasia esculenta, Dillenia indica, Euphorbia ligularia, Garcinia pedunculata, Solanum indicum, Sterculia villosa and Tabernaemontana divaricata are recorded for the first time based on globally published literature as medicinal plants used for treating diabetes mellitus and related symptoms. Conclusions: The wide variety of plants that are used to treat diabetes mellitus in this area supports the traditional value that medicinal plants have in the primary health care system of the rural people of Dhemaji district of Assam. The finding of new plant uses in the current study reveals the importance of the documentation of such ethnobotanical knowledge. (C) 2011 Elsevier Ireland Ltd. All rights reserved.

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Monoterpenoid indole alkaloids (MIA) are among the largest and most complex group of nitrogen containing secondary metabolites that are characteristic of the Apocynaceae plant family including the most notable Catharanthus roseus. These compounds have demonstrated activity as successful drugs for treating various cancers, neurological disorders and cardiovascular conditions. Due to the low yields of these compounds and high pharmacological value, their biosynthesis is a major topic of study. Previous work highlighting the leaf epidermis and leaf surface as a highly active area in MIA biosynthesis and MIA accumulation has made the epidermis a major focus of this thesis. This thesis provides an in-depth analysis of the valuable technique of RNA in situ hybridization (ISH) and demonstrates the application of the technique to analyze the location of the biosynthetic steps involved in the production of MIAs. The work presented in this thesis demonstrates that most of the MIAs of Eurasian Vinca minor, African Tabernaemontana e/egans and five Amsonia species, including North American Amsonia hubrichitii and Mediterranean A. orienta/is, accumulate in leaf wax exudates, while the rest of the leaf is almost devoid of alkaloids. Biochemical studies on Vinca minor displayed high tryptophan decarboxylase (TOe) enzyme activity and protein expression in the leaf epidermis compared to whole leaves. ISH studies aimed at localizing TOe and strictosidine synthase suggest the upper and lower epidermis of V. minor and T. e/egans as probable significant production sites for MIAs that will accumulate on the leaf surface, however the results don't eliminate the possibility of the involvement of other cell types. The monoterpenoid precursor to all MIAs, secologanin, is produced through the MEP pathway occurring in two cell types, the IPAP cells (Gl0H) and epidermal cells (LAMT and SLS). The work presented in this thesis, localizes a novel enzymatic step, UDPG-7-deoxyloganetic acid glucosyltransferase (UGT8) to the IPAP cells of Catharanthus longifolius. These results enable the suggestion that all steps from Gl0H up to and including UGT8 occur in the IPAP cells of the leaf, making the IPAP cells the main site for the majority of secologanin biosynthesis. It also makes the IPAP cells a likely cell type to begin searching for the gene of the uncharacterized steps between Gl0H and UGT8. It also narrows the compound to be transported from the IPAP cells to either 7-deoxyloganic acid or loganic acid, which aids in the identification of the transportation mechanism.

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The plant family Apocynaceae accumulates thousands of monoterpene indole alkaloids (MIAs) which originate, biosynthetically, from the common secoiridoid intermediate, strictosidine, that is formed from the condensation of tryptophan and secologanin molecules. MIAs demonstrate remarkable structural diversity and have pharmaceutically valuable biological activities. For example; a subunit of the potent anti-neoplastic molecules vincristine and vinblastine is the aspidosperma alkaloid, vindoline. Vindoline accumulates to trace levels under natural conditions. Research programs have determined that there is significant developmental and light regulation involved in the biosynthesis of this MIA. Furthermore, the biosynthetic pathway leading to vindoline is split among at least five independent cell types. Little is known of how intermediates are shuttled between these cell types. The late stage events in vindoline biosynthesis involve six enzymatic steps from tabersonine. The fourth biochemical step, in this pathway, is an indole N-methylation performed by a recently identified N-methyltransfearse (NMT). For almost twenty years the gene encoding this NMT had eluded discovery; however, in 2010 Liscombe et al. reported the identification of a γ-tocopherol C-methyltransferase homologue capable of indole N-methylating 2,3-dihydrotabersonine and Virus Induced Gene Silencing (VIGS) suppression of the messenger has since proven its involvement in vindoline biosynthesis. Recent large scale sequencing initiatives, performed on non-model medicinal plant transcriptomes, has permitted identification of candidate genes, presumably involved, in MIA biosynthesis never seen before in plant specialized metabolism research. Probing the transcriptome assemblies of Catharanthus roseus (L.)G.Don, Vinca minor L., Rauwolfia serpentine (L.)Benth ex Kurz, Tabernaemontana elegans, and Amsonia hubrichtii, with the nucleotide sequence of the N-methyltransferase involved in vindoline biosynthesis, revealed eight new homologous methyltransferases. This thesis describes the identification, molecular cloning, recombinant expression and biochemical characterization of two picrinine NMTs, one from V. minor and one from R. serpentina, a perivine NMT from C. roseus, and an ajmaline NMT from R. serpentina. While these TLMTs were expressed and functional in planta, they were active at relatively low levels and their N-methylated alkaloid products were not apparent our from alkaloid isolates of the plants. It appears that, for the most part, these TLMTs, participate in apparently silent biochemical pathways, awaiting the appropriate developmental and environmental cues for activity.

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O potencial alelopático de quatro diferentes extratos de plantas medicinais (Eclipta alba, Gomphrena globosa, Tabernaemontana catharinensis e Tithonia diversifolia) foi avaliado na germinação de Bidens pilosa e Lactuca sativa. Dentre os resultados obtidos no teste de germinação, notou-se um maior poder inibitório do extrato de G. globosa sobre sementes e plântulas de Bidens pilosa e Lactuca sativa independente da concentração utilizada e aumento da atividade inibitória de extratos T. catharinensis e de T. diversifolia com aumento da concentração destes. Quanto ao Índice de Velocidade de Germinação, os dados demonstraram redução do índice devido a elevada mortalidade das plântulas submetidas aos extratos de G. globosa e de T. catharinensis e a germinação tardia das sementes submetidas ao extrato de T. diversifolia. Quanto ao vigor das sementes, as menores porcentagens de sobrevivência ocorreram extratos à 2,5% para B. pilosa e 10% para L. sativa.

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A total of 24 extracts from 14 plant species collected at the state of Minas Gerais, Brazil, and belonging to five botanical families (Annonaceae, Apocynaceae, Ochnaceae, Polygonaceae and Vitaceae) was screened for cytotoxicity in cultured Vero cells and for antiviral activity against human herpes virus type 1 (HSV-1), vaccinia virus (VACV) and murine encephalomyocarditis virus (EMCV). The highest cytotoxicity (CC 50 < 10 μg/mL) was observed for the ethanol extracts from Annona coriacea fruits and seeds. Extracts from Hancornia speciosa, Ouratea castaneafolia and O. semisrrata were the only ones that have shown activity against all the three viruses assayed. Extracts from Polygonum spectabile, Hancornia speciosa, Himatanthus phagedaenica, Ouratea spectabilis and O. semiserrata were the most active against HSV-1 (EC 50 < 50 mg/mL), with favorable SI values (8.0 to 10.0). Hancornia speciosa and Anaxagorea dolichocarpa were the most active against EMCV (EC 50 50 - 100 μg/mL), with reasonable SI values (5.2 to 6.1), while moderate to low activity (EC 50 > 100 μg/mL) was observed for Ouratea spectabilis and O. semiserrata. A total of 7 plant species, Ouratea semiserrata, O. spectabilis, O. castanaeafolia, Rollinia laurifolia, Cissus erosa, Polygonum spectabile, and Hancornia speciosa, were active against VACV, disclosing EC50 < 50 μg/mL and SI values ranging from 6.6 to 67.3. In total, 10 out of the 14 species were selected from a literature survey on plants used to treat viral diseases in Brazil; these species were responsible for 70% of the positive results.