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1.
Nat Prod Res ; 37(5): 809-818, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35724374

RESUMO

Androsta-1,4-dien-3,16-dione was isolated for the first time from the plant kingdom of the ethanolic extract of the Ravenala madagascariensis' inflorescence by the bio-guided method. Its structure was elucidated by NMR and MS spectroscopic data analysis. The vascular effects of ethanol extracts, fractions and androsta-1,4-dien-3,16-dione were assessed on the phenylephrine pre-contracted isolated rat aorta. The isolated compound exerted the most potent vaso-relaxing effect (EC50 = 109.32 ± 15.82 µM) than the ethanol extract and fractions. The pharmacological mechanism of its vaso-relaxing action was analysed on isolated rat aorta using free-endothelial vascular tissue, specific contracting reagents (CaCl2 and KCl), antagonist (propranolol), enzyme inhibitors (L-NAME, methylene blue) and channel blocker (glibenclamide). Its vaso-relaxing activity could be due, at least partly, to the non-specific inhibition of the calcic influx.


Assuntos
Strelitziaceae , Vasodilatadores , Ratos , Animais , Vasodilatadores/química , Inflorescência , Extratos Vegetais/farmacologia , Etanol/farmacologia , Vasodilatação
2.
Sci Rep ; 11(1): 21965, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34753985

RESUMO

Madagascar's emblematic traveller's tree is a monospecific genus within Strelitziaceae, the family of the South African bird of paradise. Until now, this endemic genus consisted of a single species: Ravenala madagascariensis Sonn., which is grown everywhere in the tropics as an ornamental plant. The plant is immediately recognizable for its huge fan-forming banana-like leaves and is locally referred to in Magagascar by several vernacular names. "Variants" have been mentioned in the literature, but without any attempt to recognize formal taxa based on diagnostic features. In this paper, we formally describe five new species and fix the application of the name R. madagascariensis to the populations growing on the eastern coast of Madagascar, with the epitype growing in the marshy Fort-Dauphin area in the south. This paper has numerous implications for conservation biology and other domains of life sciences, due to the importance of this genus for the conservation of Madagascan ecosystems, the ornamental plant trade, as well as for its invasive status in several tropical areas.


Assuntos
Strelitziaceae/classificação , Ecossistema , Madagáscar , Filogenia , Especificidade da Espécie
3.
Mol Ecol Resour ; 21(1): 263-286, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32937018

RESUMO

Genome assemblies are currently being produced at an impressive rate by consortia and individual laboratories. The low costs and increasing efficiency of sequencing technologies now enable assembling genomes at unprecedented quality and contiguity. However, the difficulty in assembling repeat-rich and GC-rich regions (genomic "dark matter") limits insights into the evolution of genome structure and regulatory networks. Here, we compare the efficiency of currently available sequencing technologies (short/linked/long reads and proximity ligation maps) and combinations thereof in assembling genomic dark matter. By adopting different de novo assembly strategies, we compare individual draft assemblies to a curated multiplatform reference assembly and identify the genomic features that cause gaps within each assembly. We show that a multiplatform assembly implementing long-read, linked-read and proximity sequencing technologies performs best at recovering transposable elements, multicopy MHC genes, GC-rich microchromosomes and the repeat-rich W chromosome. Telomere-to-telomere assemblies are not a reality yet for most organisms, but by leveraging technology choice it is now possible to minimize genome assembly gaps for downstream analysis. We provide a roadmap to tailor sequencing projects for optimized completeness of both the coding and noncoding parts of nonmodel genomes.


Assuntos
Genoma de Planta , Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Análise de Sequência de DNA , Strelitziaceae/genética , Elementos de DNA Transponíveis , Genômica/métodos
4.
Molecules ; 25(7)2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32276509

RESUMO

Hyaluronidase enzyme (HAase) has a role in the dissolution or disintegration of hyaluronic acid (HA) and in maintaining the heathy state of skin. Bioassay-guided fractionation of Ravenala madagascariensis (Sonn.) organ extracts (leaf, flower, stem, and root) testing for hyaluronidase inhibition was performed followed by metabolic profiling using LC-HRMS. Additionally, a hyaluronidase docking study was achieved using Molecular Operating Environment (MOE). Results showed that the crude hydroalcoholic (70% EtOH) extract of the leaves as well as its n-butanol (n-BuOH) partition showed higher HAase activity with 64.3% inhibition. Metabolic analysis of R. madagascariensis resulted in the identification of 19 phenolic compounds ranging from different chemical classes (flavone glycosides, flavonol glycosides, and flavanol aglycones). Bioassay-guided purification of the leaf n-BuOH partition led to the isolation of seven compounds that were identified as narcissin, rutin, epiafzelechin, epicatechin, isorhamnetin 7-O-glucoside, kaempferol, and isorhamnetin-7-O-rutinoside. The docking study showed that narcissin, rutin, and quercetin 3-O-glucoside all interact with HAase through hydrogen bonding with the Asp111, Gln271, and/or Glu113 residues. Our results highlight Ravenala madagascariensis and its flavonoids as promising hyaluronidase inhibitors in natural cosmetology preparations for skin care.


Assuntos
Bioensaio/métodos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Hialuronoglucosaminidase/antagonistas & inibidores , Metabolômica , Simulação de Acoplamento Molecular , Strelitziaceae/química , Inibidores Enzimáticos/isolamento & purificação , Metaboloma , Polifenóis/química , Termodinâmica
5.
Afr J Tradit Complement Altern Med ; 14(2): 253-262, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28573242

RESUMO

BACKGROUND: The fortuitous discovery of an animal pigment bilirubin found in the plant Strelitzia nicolai has opened an enormous number of questions regarding bilirubin's formation and its ultimate function in the human body. MATERIALS AND METHODS: A methodical review of bilirubin in humans and animals was carried out, information was gathered using published scientific journals, books and conference proceedings. Articles based on case studies of elevated levels of bilirubin were analysed thoroughly. RESULTS: Even though for numerous years bilirubin was assumed to be merely a desecrate product of the heme catabolic pathway by greatest, and a likely lethal compound at worst; statistics from the last few decades clearly shows that placidly high serum bilirubin levels are robustly related to have abundant beneficial effects on the human body. CONCLUSION: This study reveals new insights into the presence of the only animal pigment found in Strelitzia nicolai arils, the potential advantages of bilirubin found in a plant and its therapeutic value indications. This review hopes to resuscitate researchers' credence regarding bilirubin as a toxic compound.


Assuntos
Bilirrubina , Extratos Vegetais , Strelitziaceae/química , Animais , Bilirrubina/sangue , Bilirrubina/uso terapêutico , Humanos , Extratos Vegetais/uso terapêutico , Sementes/química
6.
Afr J Tradit Complement Altern Med ; 14(3): 147-156, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28480426

RESUMO

BACKGROUND: The discovery of the only animal pigment, bilirubin, in the plant Strelitzia nicolai has triggered a vast number of questions regarding bilirubin's formation and its role in the human body. Recent studies have confirmed that bilirubin at certain levels have many medical benefits. Various case studies have revealed that bilirubin is a potent antioxidant. Cervical cancer is one of South Africa's largest womens' health crises. It is estimated that it affects one out of 41 South African women and kills approximately 8 women in the country every day. Thus, the aim of this study was to investigate if the aril extract of Strelitzia nicolai (Regel and Körn.) containing bilirubin possesses anti-cancer activity and to determine its effect on the induction of apoptosis. MATERIALS AND METHODS: The DPPH activity was firstly used to determine the antioxidant effect of the extract. Thereafter, the cytotoxic effect was tested using the XTT assay. Apoptosis was confirmed and quantified using the Annexin V-PE kit and the morphology was studied using acridine orange and ethidium bromide. RESULTS: The aril extract decreased cell viability by 52% and induced apoptosis in HeLa cells; as shown by the Annexin V-PE Apoptosis detection kit and morphological studies with acridine orange/ethidium bromide staining. CONCLUSION: The activity of the extract as a potent antioxidant was immensely enhanced as compared to the bilirubin standard. These results suggest that S. nicolai aril extract containing bilirubin works synergistically as opposed to bilirubin on its own. Furthermore, this extract might be a good candidate for the therapeutic intervention of cervical cancer.


Assuntos
Antioxidantes/farmacologia , Bilirrubina/farmacologia , Frutas/química , Extratos Vegetais/farmacologia , Strelitziaceae/química , Antioxidantes/química , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Células HeLa , Humanos , Extratos Vegetais/química
7.
J Econ Entomol ; 109(1): 249-54, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26494708

RESUMO

Fecundity is defined as the number of progeny produced by an organism. In our study, we used three different experimental settings to measure the fecundity of rugose spiraling whitefly (Aleurodicus rugioperculatus Martin), a recent invasive insect in Florida, on Strelitzia nicolai host plants. The adult longevity was significantly different among treatments, with females surviving significantly longer in groups in whole-plant cages and individual females in clip cages compared with individual females in whole-plant cages. Females laid 34.5 ± 8.4, 156.4 ± 18.3, and 225.2 ± 18 eggs, on average, when kept individually in whole-plant cages, in a group in whole-plant cages, and individually in clip cages, respectively. In all treatments, there was a significant correlation between the longevity and fecundity of females. Males emerged earlier than females in all treatments. Virgin females produced only males in the F1, while mated females produced both males and females, which suggests an arrhenotokous parthenogenesis. The egg-to-adult survival of the whitefly was 29 ± 4%, and the highest mortality occurred at the crawler stage when reared on S. nicolai. The results showed a significant effect of aggregation and cage setting on longevity and fecundity of this whitefly. To conclude, the experimental setting of the group fecundity treatment is more similar to what occurs in the landscape. Such a significant effect of cage setting and aggregation on the life-history parameters should be always taken into account when designing experiments or interpreting results.


Assuntos
Heterópteros/fisiologia , Animais , Feminino , Fertilidade , Cadeia Alimentar , Tábuas de Vida , Longevidade , Masculino , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologia , Partenogênese , Strelitziaceae/crescimento & desenvolvimento
8.
Biosci. j. (Online) ; 30(5 Supplement 2): 783-790, 2014. ilus, tab
Artigo em Português | LILACS | ID: biblio-947974

RESUMO

O presente trabalho tem por objetivo de estudar a influência da temperatura de armazenamento (câmara fria e temperatura ambiente) na qualidade das inflorescências de estrelítzia. Escapos florais foram selecionados, etiquetados e descartados quanto à presença de danos mecânicos, doenças e/ou pragas. Transcorrido esse período, foram transferidos para recipientes, onde foram submetidos a dois experimentos. No experimento 1, escapos foram colocados em baldes contendo água da rede pública e levadas para câmara fria a 7,5 ºC e UR de 90%, por um período de doze dias. No experimento 2, os escapos foram mantidos nas mesmas condições, porém em temperatura ambiente por um período de seis dias. Nos dois experimentos, as análises visuais: coloração, brilho, manchas (através da atribuição de notas), abertura e queda de floretes (contagem) foram avaliadas em intervalo de quatro dias em câmara fria e a cada 48 horas em condições de temperatura ambiente. A sépala foi o órgão que apresentou maior perda na coloração. A variável brilho apresentou o mesmo comportamento em relação aos dois experimentos. Maiores incidências de manchas nas inflorescências ocorreram em temperatura ambiente. Os escapos apresentaram aumento no número de floretes abertos em câmara fria. Essa tendência não ocorreu em temperatura ambiente. Não foram observados diferenças na queda de floretes. Conclui-se que a temperatura de armazenamento não contribui para a qualidade pós-colheita de estrelítzia.


This work was based to study the influence of the storage temperature (cold and room temperature) in the quality of inflorescences strelitzia. The scapes were selected, labeled and there were zero problems concerning mechanical damage, disease and/or plagues. Subsequently this period, the scapes were moved randomly to recipients with water, in which two postharvest trials were conducted. In experiment 1, the flower scapes were placed in buckets with water from public supply and sanitation department and taken to a cold room at temperature of 7.5 ºC and RH of 90%, for a twelve day period. For the experiment 2, were kept under the same conditions but at room temperature for a period of six days. In both experiments, the visual analysis: color, gloss, stains (by assigning notes), opening and drop florets (count) were evaluated at intervals of four days in cold and every 48 hours at ambient temperature conditions. In both experiments, the visual analysis: color, gloss, stains (by assigning notes), opening and drop florets (count) were evaluated at intervals of four days in cold and every 48 hours at ambient temperature conditions. The sepal is the organ that showed greater loss in coloration. The variable gloss showed the same pattern for the two experiments. Incidences of stains on the inflorescences occurred in patches at room temperature. The scapes increased number of florets open in cold. This tendency did not occur at room temperature. No were observed differences in the fall of florets. Conclude that the storage temperature does not contribute to postharvest quality of strelitzia.


Assuntos
Temperatura , Envelhecimento , Strelitziaceae , Inflorescência
9.
Langmuir ; 28(11): 5312-7, 2012 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-22401575

RESUMO

Artificial surfaces that exhibit unidirectional water spreading and superhydrophobicity are obtained by Strelitzia reginae leaves. Both green and dried leaves are used, thus exploiting the plant senescence. We demonstrate that the natural drying process of the leaves strongly affects the surface morphology and wettability. Polymeric stamps from the green leaf show an arrangement of periodic microridges/microgrooves that favor anisotropic wetting, with a water contact angle (WCA) variation of about 21% along the two principal directions. Instead, the shrinkage of the leaf tissue, as a consequence of the natural dehydration process, induces an enhancement of the superficial corrugation. This results in the establishment of a superhydrophobic state, which shows a WCA of up to 160°, and water rolling off. S. reginae leaves are therefore easily accessible stamps suitable for controlling wettability and realizing surfaces that exhibit various wetting behaviors.


Assuntos
Folhas de Planta/química , Strelitziaceae/química , Molhabilidade , Microscopia Eletrônica de Varredura , Água
10.
Bioinspir Biomim ; 6(4): 045001, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22126741

RESUMO

This paper presents a novel biomimetic approach to the kinematics of deployable systems for architectural purposes. Elastic deformation of the entire structure replaces the need for local hinges. This change becomes possible by using fibre-reinforced polymers (FRP) such as glass fibre reinforced polymer (GFRP) that can combine high tensile strength with low bending stiffness, thus offering a large range of calibrated elastic deformations. The employment of elasticity within a structure facilitates not only the generation of complex geometries, but also takes the design space a step further by creating elastic kinetic structures, here referred to as pliable structures. In this paper, the authors give an insight into the abstraction strategies used to derive elastic kinetics from plants, which show a clear interrelation of form, actuation and kinematics. Thereby, the focus will be on form-finding and simulation methods which have been adopted to generate a biomimetic principle which is patented under the name Flectofin®. This bio inspired hingeless flapping device is inspired by the valvular pollination mechanism that was derived and abstracted from the kinematics found in the Bird-Of-Paradise flower (Strelitzia reginae, Strelitziaceae).


Assuntos
Materiais Biomiméticos , Materiais de Construção , Decoração de Interiores e Mobiliário/instrumentação , Modelos Biológicos , Polinização/fisiologia , Strelitziaceae/fisiologia , Simulação por Computador , Desenho Assistido por Computador , Módulo de Elasticidade/fisiologia , Desenho de Equipamento , Análise de Falha de Equipamento
11.
J Am Chem Soc ; 131(8): 2830, 2009 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-19206232

RESUMO

The bile pigment bilirubin-IXalpha is the degradative product of heme, distributed among mammals and some other vertebrates. It can be recognized as the pigment responsible for the yellow color of jaundice and healing bruises. In this paper we present the first example of the isolation of bilirubin in plants. The compound was isolated from the brilliant orange-colored arils of Strelitzia nicolai, the white bird of paradise tree, and characterized by HPLC-ESMS, UV-visible, (1)H NMR, and (13)C NMR spectroscopy, as well as comparison with an authentic standard. This discovery indicates that plant cyclic tetrapyrroles may undergo degradation by a previously unknown pathway. Preliminary analyses of related plants, including S. reginae, the bird of paradise, also revealed bilirubin in the arils and flowers, indicating that the occurrence of bilirubin is not limited to a single species or tissue type.


Assuntos
Bilirrubina/isolamento & purificação , Strelitziaceae/química , Bilirrubina/química , Bilirrubina/metabolismo , Cromatografia Líquida de Alta Pressão , Ligação de Hidrogênio , Ressonância Magnética Nuclear Biomolecular , Strelitziaceae/metabolismo , Tetrapirróis/metabolismo
12.
In Silico Biol ; 8(5-6): 413-25, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19374128

RESUMO

Nucleotide sequences of catalase were obtained following amplification using specific primers and were blasted against Musa acuminata catalase 2 mRNA from NCBI (157418810). Clustering of the amino acid sequences from NCBI was done using Clustal X. The latter revealed that FHIA18 catalase is more related to Ravenala madagascariensis (Musa relative) catalase while the Williams catalase is more related to a clade containing a Musa acuminata (Musa ancestor) catalase from NCBI. The tertiary structures and the catalase consensus functional sites, based on the Pseudomonas syringae catalase structural template, were obtained for FHIA18, Williams, Ravenala madagascariensis and Musa acuminata catalases. They were found to differ slightly. Using known features of catalase active sites, four pre-requisite criteria were defined to find such sites: (1) Position of tyrosine axial to heme determined by X-ray diffraction, (2) 7 conserved amino acids in the active site found by sequence alignment, (3) favourable docking energy, and (4) presence of an unobstructed long tunnel that leads the ligand to the active site. Two differing potential docking sites were found for both FHIA18 and Williams that fit a maximum number of criteria. In terms of 1D sequence, the region of the docking site for Williams is within the catalase domains as seen upon NCBI blast. The counterpart of FHIA18 for the same region is not. This sequence difference between FHIA18 and Williams affects the best docking site in FHIA18 and Williams in silico.


Assuntos
Catalase/química , Musa/classificação , Musa/enzimologia , Strelitziaceae/enzimologia , Sequência de Aminoácidos , Animais , Sítios de Ligação , Catalase/genética , Catalase/metabolismo , Simulação por Computador , Sequência Conservada , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Imageamento Tridimensional , Modelos Moleculares , Dados de Sequência Molecular , Musa/genética , Filogenia , Estrutura Terciária de Proteína , Alinhamento de Sequência , Strelitziaceae/genética , Homologia Estrutural de Proteína , Zantedeschia/enzimologia , Zantedeschia/genética
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