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1.
Preprint en Portugués | SciELO Preprints | ID: pps-810

RESUMEN

This study provides a floristic survey of the Bixaceae from Paraná State. The family is represented in the area by two species: Cochlospermum regium (Mart. ex Schrank) Pilg., native from the remnants of the Cerrado biome, and Bixa orellana L., which has an uncertain origin but occurs sub-spontaneously in Paraná State. Descriptions, an identification key, photographs, and comments on the taxonomy of these species are provided.


Este trabalho apresenta o tratamento florístico de Bixaceae para o Estado do Paraná. A família está representada por duas espécies: Cochlospermum regium (Mart. ex Schrank) Pilg., nativa dos remanescentes de Cerrado; e Bixa orellana L., de origem incerta, mas subespontânea no Estado do Paraná. São apresentadas descrições, uma chave de identificação para as espécies, pranchas fotográficas e comentários taxonômicos.

2.
Mol Phylogenet Evol ; 139: 106553, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31288103

RESUMEN

Eugenia has a pantropical distribution and comprises ca. 1000 species found mostly in the Neotropics. Recent DNA based phylogenies show that unusual flower morphology of 'eugenioid' collections, e.g. fused calices that open by tearing, consistently emerged within Eugenia. These results emphasize a demand to revaluate flower morphology in a phylogenetic context within the genus. A reassessment of calyx fusion in Eugenia and traditionally related genera is here focused on clarification of the systematic relevance of this apparently recurrent characteristic. Twenty-four Eugenia species with some level of calyx fusion in the bud were newly used (one nuclear and four plastid markers) in conjunction with a representative sample of previously sequenced species to recover a time-calibrated Eugenia phylogeny of 86 accessions. Development of the fused calyx was analysed using scanning electron microscopy, differing patterns were re-coded and subsequently phylogenetic character reconstruction was performed. Eugenia was recovered as monophyletic including the traditionally segregated genera Calycorectes and Catinga. Ancestral character reconstruction uncovered free calyx lobes as the ancestral condition. Five development patterns leading to calyx fusion are reported in Eugenia including species with apparently six petals, which contrast with the standard tetramerous flowers. This condition is interpreted as the petaloid pattern, where two external fused calyx lobes cover the bud while two internal calyx lobes are free and petaloid. The fused calyx condition is homoplastic and evolved independently, several times in Eugenia, as did the different development patterns. Data presented here show that systematic incongruence resulting from multiple, independent origins of the fused calyx in Eugenia is further aggravated by an inability to distinguish parallelism and convergence within the recovered patterns.


Asunto(s)
Evolución Biológica , Eugenia/anatomía & histología , Flores/anatomía & histología , Animales , Secuencia de Bases , Biodiversidad , Calibración , Flores/genética , Filogenia , Factores de Tiempo
3.
Mol Phylogenet Evol ; 108: 34-48, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28161152

RESUMEN

Many recent studies discuss the influence of climatic and geological events in the evolution of Neotropical biota by correlating these events with dated phylogenetic hypotheses. Myrtaceae is one of the most diverse Neotropical groups and it therefore a good proxy of plant diversity in the region. However, biogeographic studies on Neotropical Myrtaceae are still very limited. Myrcia s.l. is an informal group comprising three accepted genera (Calyptranthes, Marlierea and Myrcia) making up the second largest Neotropical group of Myrtaceae, totalling about 700 species distributed in nine subgroups. Exclusively Neotropical, the group occurs along the whole of the Neotropics with diversity centres in the Caribbean, the Guiana Highlands and the central-eastern Brazil. This study aims to identify the time and place of divergence of Myrcia s.l. lineages, to examine the correlation in light of geological and climatic events in the Neotropics, and to explore relationships among Neotropical biogeographic areas. A dated phylogenetic hypothesis was produced using BEAST and calibrated by placing Paleomyrtinaea princetonensis (56Ma) at the root of the tree; biogeographic analysis used the DEC model with dispersal probabilities between areas based on distance and floristic affinities. Myrcia s.l. originated in the Montane Atlantic Forest between the end of Eocene and early Miocene and this region acted as a secondary cradle for several lineages during the evolution of this group. The Caribbean region was important in the diversification of the Calyptranthes clade while the Guayana shield appears as ancestral area for an older subgroup of Myrcia s.l. The Amazon Forest has relatively low diversity of Myrcia s.l. species but appears to have been important in the initial biogeographic history of old lineages. Lowland Atlantic Forest has high species diversity but species rich lineages did not originate in the area. Diversification of most subgroups of Myrcia s.l. occurred throughout the Miocene, as reported for other Neotropical taxa. During the Miocene, geological events may have influenced the evolution of the Caribbean and Amazon forest lineages, but other regions were geological stable and climate changes were the most likely drivers of diversification. The evolution of many lineages in montane areas suggests that Myrcia s.l. may be particularly adapted to such environments.


Asunto(s)
Clima , Geología , Myrtaceae/clasificación , Filogeografía , Clima Tropical , Teorema de Bayes , Brasil , Región del Caribe , Modelos Teóricos , Myrtaceae/anatomía & histología , Filogenia , Dispersión de Semillas/fisiología , Factores de Tiempo
4.
PLoS One ; 10(11): e0141187, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26559183

RESUMEN

In the present study, we describe and illustrate a remarkable new species of Syngonanthus from South America (Bolivia, Brazil and Peru). This new species is quickly distinguished from all species in the genus by trimerous and bisexual flowers, a unique set of characteristics in Syngonanthus. Complementary to this study, sequences of 33 species were downloaded from GenBank and four species had sequences newly generated for this study. Molecular phylogenetic analyses based on nuclear ribosomal ITS and the plastid regions psbA-trnH and trnL-F were performed to determine its systematic position. The results have shown S. androgynus closely related to a well-supported clade that has been treated as Syngonanthus sect. Carphocephalus. Floral traits associated with this new plant also were surveyed. Character reconstruction suggests that the bisexual flowers originated independently more than once in the genus. However, trimerous flowers appear to be an ancestral condition of the whole genus.


Asunto(s)
Evolución Biológica , Eriocaulaceae/fisiología , Filogenia , Eriocaulaceae/clasificación , Flores/fisiología , Meristema/fisiología , Datos de Secuencia Molecular , América del Sur
5.
BMC Complement Altern Med ; 15: 391, 2015 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-26511617

RESUMEN

BACKGROUND: Syngonanthus arthrotrichus and Syngonanthus bisulcatus, currently known for Comanthera aciphylla (Bong.) L.R.Parra & Giul. and Comanthera bisulcata (Koern.) L.R. Parra & Giul, popularly known in Brazil as "sempre-vivas," are plants from the family Eriocaulaceae. They are found in the states of Minas Gerais and Bahia. The species are known to be rich in flavonoids to which their gastroprotective activity has been attributed. In this research, experimental protocols were performed to elucidate the associated mechanisms of action. METHODS: The activity was evaluated using induced gastric ulcer models (acetic acid and ethanol-induced gastric lesions in NEM or L-NAME pre-treated mice, and by ischemia/reperfusion). Antioxidant enzymes, serum somatostatin, and gastrin were also evaluated. RESULTS: In chronic gastric ulcers, a single daily oral dose of Sa-FRF or Sb-FRF (100 mg/kg body wt.) for 14 consecutive days accelerated ulcer healing to an extent similar to that seen with an equal dose of cimetidine. The pre-treatment of mice with NEM (N-ethylmaleimide) or L-NAME (N-nitro-L-arginine) abolished the protective activity of Sa-FRF, Sa-FDF, Sb-FDF and Sb-FRF or Sa-FRF and Sb-FRF, respectively, which indicates that antioxidant compounds and nitric oxide synthase activity are involved in the gastroprotective. Sa-FRF and Sb-FRF (100 mg/kg p.o) protected the gastric mucosa against ulceration that was induced by ischemia/reperfusion (72 and 76 %, respectively). It also decreased lipid peroxidation and restored total thiols in the gastric wall of mice that had been treated with ethanol. When administered to rats submitted to ethanol-induced gastric lesions, Sa-FRF and Sb-FRF (100 mg/kg, p.o.) increased the somatostatin serum levels, while the gastrin serum levels were proportionally decreased. CONCLUSIONS: The results indicate significant healing effects and gastroprotective activity for the Sa-FRF and Sb-FRF, which probably involves the participation of SH groups, nitric oxide (NO), the antioxidant system, somatostatin, and gastrin. All are integral parts of the gastrointestinal mucosa's cytoprotective mechanisms against aggressive factors.


Asunto(s)
Antiulcerosos/administración & dosificación , Eriocaulaceae/química , Extractos Vegetales/administración & dosificación , Sustancias Protectoras/administración & dosificación , Úlcera Gástrica/tratamiento farmacológico , Animales , Mucosa Gástrica/efectos de los fármacos , Mucosa Gástrica/metabolismo , Humanos , Masculino , Ratones , Óxido Nítrico/metabolismo , Ratas , Ratas Wistar , Úlcera Gástrica/metabolismo , Úlcera Gástrica/fisiopatología , Cicatrización de Heridas/efectos de los fármacos
6.
Molecules ; 18(1): 244-62, 2012 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-23271464

RESUMEN

A HPLC-ESI-IT-MSn method, based on high-performance liquid chromatography coupled to electrospray negative ionization multistage ion trap mass spectrometry, was developed for rapid identification of 24 flavonoid and naphthopyranone compounds. The methanol extracts of the capitulae and scapes of P. chiquitensis exhibited mutagenic activity in the Salmonella/microsome assay, against strain TA97a.


Asunto(s)
Eriocaulaceae/química , Flavonoides/química , Extractos Vegetales/química , Cromatografía Líquida de Alta Presión , Mutágenos/toxicidad , Extractos Vegetales/farmacología , Salmonella/efectos de los fármacos , Salmonella/crecimiento & desarrollo , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masas en Tándem
7.
PhytoKeys ; (10): 7-12, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22461727

RESUMEN

Syngonanthus weddellii var. gracilis Moldenke, (1973) was described very briefly based on a single collection. A careful analysis reveals that this variety has dimerous flowers, free petals of the pistillate flower and bifid stigmatic branches. It is therefore misplaced in Syngonanthus Ruhland (1900). We transfer it to Paepalanthus Mart. (1834) at the species level, as it is distinct from morphologically similar species: Paepalanthus flaccidus (Bong.) Koern. (1863), Paepalanthus trichophyllus (Bong.) Koern. (1863), and Paepalanthus strictus Koern. (1863). The epithet gracilis is no longer available, hence, we have coined the name Paepalanthus rectifolius. We also provide a full description, illustrations, a distribution map, and pertinent comments.

8.
Z Naturforsch C J Biosci ; 63(3-4): 169-75, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18533457

RESUMEN

Eriocaulaceae is a pantropical family that comprises about 1100 species distributed in 11 genera. The infrafamilial relationships are still unsatisfactorily resolved, because of the tiny flowers and generalized morphology, which makes the taxonomy very difficult. Flavonoid and naphthopyranone profiles have proved to be important in order to contribute to the alignment of genera into the family. We here present a survey of the chemical data of Eriocaulaceae with a discussion about their contribution to the taxonomy of Eriocaulaceae.


Asunto(s)
Eriocaulaceae/química , Flavonas/análisis , Eriocaulaceae/clasificación , Flavonas/química , Flavonoides/química , Flavonoides/aislamiento & purificación , Modelos Moleculares , Conformación Molecular , Relación Estructura-Actividad , Xantonas/análisis , Xantonas/química
9.
Chem Pharm Bull (Tokyo) ; 55(11): 1635-9, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17978526

RESUMEN

A new acylated flavonoid, 6,4'-dimethoxyquercetin-3-O-beta-D-6''[3,4,5-trihydroxy (E)-cinnamoyl]glucopyranoside, and a naphthopyranone dimer, named eriocauline, together with 2 other known flavonoids, 6-methoxyapigenin-7-O-beta-D-glucopyranoside and 6-methoxyapigenin-7-O-beta-D-allopyranoside, have been isolated from the capitulae of Eriocaulon ligulatum. The compounds were identified using spectroscopic methods (HR-ESI-MS, and 1-D and 2-D NMR). The methanol extract exhibited mutagenic activity in the Salmonella/microsome assay, in strains TA100, TA97a and TA102 and for dichloromethane extract tested in strain TA98.


Asunto(s)
Eriocaulaceae/química , Flavonoides/farmacología , Microsomas/efectos de los fármacos , Naftalenos/farmacología , Extractos Vegetales/química , Plantas Medicinales/química , Pironas/farmacología , Salmonella typhimurium/efectos de los fármacos , Acetilación , Dimerización , Eriocaulaceae/genética , Flavonoides/química , Flavonoides/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Microsomas/metabolismo , Estructura Molecular , Pruebas de Mutagenicidad , Naftalenos/química , Naftalenos/aislamiento & purificación , Extractos Vegetales/farmacología , Pironas/química , Pironas/aislamiento & purificación , Salmonella typhimurium/genética , Espectrometría de Masa por Ionización de Electrospray
10.
RBCF, Rev. bras. ciênc. farm. (Impr.) ; 40(3): 433-436, jul.-set. 2004. ilus, tab
Artículo en Inglés | LILACS | ID: lil-420693

RESUMEN

From the ethanolic extract of the capitulae of Paepalanthus microphyllus, one caffeic acid derivative (1) was isolated. The structure of the compound was caracterized by spectroscopic methods, mainly 1D and 2D NMR experiments, as well as ESMS spectrometry. In addition, three flavonoids of taxonomic relevance were isolated and identified by comparison to literature data


Asunto(s)
Ácidos Cafeicos , Extractos Vegetales , Espectroscopía de Resonancia Magnética/métodos , Espectrometría de Masas
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