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Terpenos de culturas in vitro de Duroia saccifera (Rubiaceae) e avaliação das atividades antibacteriana, antiangiogênica e antioxidante dos extratos
Get PDFDuroia saccifera (Mart. Ex Roem. & Schult.) K. Schum. (Rubiaceae) occurs in the Amazon rainforest. In natura plant extracts of the species have shown antioxidant, antimicrobial even against Mycobacterium tuberculosis activity, showing their medicinal potential. Based on this, the objective of this work was to study phytochemically and some biological activities of extracts of in vitro D. saccifera cultures, as well as to describe differences involved in in vitro propagation methods and calogenesis induction time, based on the chemical profile of the extracts hexanes, ethyl acetate (EtOAc) and methanolic (MeOH) from seedlings, calli, and cell suspensions. Seedlings of D. saccifera were used to prepare seedling extracts and as a source of explants to initiate the establishment of callus and cell suspension cultures. The plant material was extracted with the organic solvents hexane, EtOAc and MeOH. Callus EtOAc and seedling MeOH extracts were fractionated in open column. All extracts and fractions were analyzed by Comparative Thin Layer Chromatography (TLC). Callus extracts and suspensions were tested in antimicrobial and antioxidant assays; cell suspension extracts were tested for angiogenic activity. Callus extracts and cell suspensions had a similar chemical profile, and the seedling extracts were remarkably different,
however, all extracts were rich in terpenoids. The comparison of the chemical profile of the extracts of the cultures and explants with different degrees of differentiation made it possible to verify the presence of iridoids only in cultures with differentiated cells. A mixture of β-sitosterol, stigmasterol and oleanolic and ursolic acid were obtained from the EtOAc extract. Seedling fractionation resulted in the isolation of the iridoid monotropein methyl ester, obtained for the first time in the species. Of the extracts tested, the EtOAc extracts of callus and suspensions and hexanic callus extract showed bacteriostatic activity. EtOAc extract from cell suspensions showed significant antiagiogenic activity. The results found in this work demonstrate the great potential of D. saccifera in vitro cultures for the supply of mainly terpenoid active secondary metabolites and stimulate the continued fractionation of callus EtOAc extract and seedling MeOH to isolate, identify and analyze other possible active substances that may lead to the discovery of new drugs for the treatment of tuberculosis.Duroia saccifera (Mart. Ex Roem. & Schult.) K. Schum. (Rubiaceae) ocorre na floresta Amazônica. Extratos de plantas in natura da espécie têm apresentado atividade antioxidante, antimicrobiana inclusive frente a Mycobacterium tuberculosis mostrando seu potencial medicinal. Com base nisso, esse trabalho teve como objetivo estudar fitoquímica e algumas atividades biológicas de extratos de culturas in vitro de D. saccifera, além de descrever diferenças envolvidas nos métodos de propagação in vitro e no tempo da indução da calogênese, baseando-se no perfil químico dos extratos hexânicos, acetato de etila (AcOEt) e metanólicos (MeOH) de plântulas, calos, e suspensões celulares. Mudas de plântulas de D. saccifera foram utilizadas para a preparação dos extratos de plântulas e como fonte de explantes para iniciar o estabelecimento dos cultivos de calos e suspensões celulares. O material vegetal foi extraído com os solventes orgânicos hexano, AcOEt e MeOH, os extratos AcOEt dos calos e MeOH das plântulas foram fracionados em coluna aberta. Todos os extratos e frações foram analisados por Cromatografia em Camada Delgada Comparativa (CCDC). Os extratos dos calos e as suspensões foram testados em ensaios antimicrobiano e antioxidante, os extratos das suspensões celulares foram testados frente a sua atividade angiogênica. Os extratos de calos e suspensões celulares apresentaram um perfil químico semelhante, sendo os extratos das plântulas notavelmente diferentes, porém, todos os extratos se mostraram ricos em terpenoides com os reveladores testados. A comparação do perfil químico dos extratos das culturas e de explantes com diferentes graus de diferenciação, possibilitou verificar a presença de iridoides somente nas culturas com células diferenciadas. Do extrato AcOEt obteve-se uma mixtura de β-sitosterol e estigmasterol e outra de ácido oleanólico e ursólico, obtidas pela primeira vez em culturas in vitro desta espécie. O fracionamento do extrato MeOH de plântulas resultou no isolamento do iridoide éster metílico de monotropeína, obtido pela primeira vez na espécie. Os extratos AcOEt dos calos e suspensões, e o extrato hexânico dos calos apresentaram atividade bacteriostática. O extrato AcOEt das suspensões celulares apresentou atividade antiangiogênica significativa. Os resultados encontrados neste trabalho demonstram o grande potencial das culturas in vitro de D. saccifera para o suprimento de metabólitos secundários ativos, principalmente terpenoides, e estimulam a continuação do fracionamento do extrato de AcOEt dos calos e MeOH das plântulas, para isolar, identificar e analisar outras possíveis substâncias ativas que podem levar à descoberta de novos medicamentos para o tratamento da tuberculose
Bats in Three Protected Areas of the Central Amazon Ecological Corridor in Brazil
No full textBats have the second highest mammalian species richness globally, and account for about half of the mammal species diversity in tropical forests. In the Neotropical region, Brazil is the second most bat species-rich country, and the Brazilian Amazonia harbours most of the Brazilian bat diversity. However, many areas of the Amazon have sampling gaps in biodiversity inventories, and this is the situation of most Protected Areas (PAs) of the Central Amazon Ecological Corridor (CAEC) of Brazil. In the CAEC, there are PAs that are relatively intact, globally relevant for biodiversity, having high priority for conservation at the regional scale, but are greatly deficient in faunal inventories. In this sense, species inventories are the first step to consolidate management plans for PAs, as well as the conservation of the species occurring there. Thus, in this study we survey the bat assemblages in three PAs in the CAEC of Brazil: Jutai River Extractive Reserve (JRER), Jutai-Solimoes Ecological Station (JSES) and Auati-Parana Extractive Reserve (APER). In addition, we compared the bat diversity of these three areas with a compilation of data from 44 localities in the Amazon biome in two different biogeographic contexts. The first involves three geographic regions separated by large Amazonian rivers (Eastern Amazonia, Western Amazonia and the Guiana Shield) and the second based on three biogeographic dominions (Boreal Brazilian, Southeastern Amazonia and South Brazilian). We recorded 36 species at JRER in ten nights of sampling, 33 species at JSES in nine nights, and 55 species at APER in 17 nights. Of the total number of species, 20 were captured exclusively at APER, seven at JSES and only four at JRER, with 21 species being common to the three PAs. One species (Artibeus bogotensis) was recorded for the first time in Brazil. In a biogeographic context, species composition differed among biogeographic regions. This suggests that when designing strategies of conservation to protect the rich diversity of the large-scale bat fauna of the Amazon, considering the location of PAs, as well as the biogeographic regions is key. Although there have been major efforts in Brazil to identify priority conservation areas, for most priority areas of Amazon, bat surveys have not been performed, highlighting the urgent need for further studies. © Museum and Institute of Zoology PAS
Rediscovery of the Neotropical water scavenger beetle Protistolophus spangleri Short with notes on its habitat and behavior (Coleoptera: Hydrophilidae: Hydrophilinae)
No full textNeuromast distribution and its relevance to feeding in Neotropical freshwater stingrays (Elasmobranchii: Potamotrygonidae)
No full textThe mechanosensory system in batoids has a unique sensory canal distribution located on both dorsal and ventral surfaces of the body. Due to the opposite position of eyes and mouth, ventral lateral-line canals are essential to detect and capture prey buried in the substrate. The present study analyzes the density of neuromasts in ventral lateral-line canals as well as their specific distribution patterns to help to understand the mechanisms involved in the foraging activities in potamotrygonid stingrays. The organization of the lateral-line canals was described in Potamotrygon albimaculata, P. jabuti and P. schroederi. Neuromasts were quantified in each canal of the ventral surface and endemic their densities were compared among P. albimaculata, P. jabuti, P. schroederi, P. wallacei, and Paratrygon aiereba. The orbito-nasal component of the infraorbital canal was examined for all genera of Potamotrygoninae to understand its origin and connection patterns. Despite similarities in the morphology of the lateral line in the examined potamotrygonid species, differences of the densities of neuromasts were observed. The distinct web-like infraorbital canal in Paratrygon aiereba held a significantly higher number of neuromasts, which apparently compensates the lower density of neuromasts along its ventral surface. The orbito-nasal component of the infraorbital canal presents connections between infraorbital and nasal canals, except for P. aiereba, which has a supra-infraorbital canals’ connection. The complex distribution of lateral line canals and their neuromasts indicate distinct sensory abilities that probably provide a high capability to detect a variety of prey in different types of substrate. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature
Ocorrência de fungos micorrízicos arbusculares em um plantio de cupuaçu na estrada de Balbina, Amazonas
No full textSynergic effects of temperature and hypoxia on enzymatic activity and genotoxicity of Colossoma macropomum (Cuvier 1818)
No full textLand use changes and relations among water physicochemistry and hydrology in the Amazonian Purus river basin, northwestern Brazil
Get PDFPercepções na Conservação da Fauna Silvestre Amazônica em Risco de Extinção
Get PDFThis work presents the perceptions of the wild fauna of residents of the Amazon communities participating in the conservation programs of the harpy eagle (Harpia harpyja) and tracaja (Podocnemis unifilis). From the systematic observation and semi-structured interviews the research discusses the constitution of perceptions in the conservation of these flagship species, from peculiar socio-historical processes and environmental knowledge in each community. The perceptions about the harpy eagle are based on the intangibility of the bird, which allows them to appreciate its beauty, and sometimes to fear its powerful claws. Conservation is based on the recognition of its wild haughtiness and maintenance of its habitat, even if distant from community life, characterizing an interspecific behavior. The perceptions about the tracajá are constituted in its docility, utility and almost domestic function. Conservation is based on trans-specific behavior, which characterizes it as a “natural” member of the community. For these people, the perception of the conservation of these species is constituted by proximity, knowledge and experiences. © 2020 Centro Universitario de Anapolis. All rights reserved
Purification and partial characterization of a new lectin from Parkia panurensis Benth. ex H.C. Hopkins seeds (Leguminosae family; Mimosoideae subfamily) and evaluation of its biological effects
No full textLectins are proteins that have as one of their main characteristics recognizing and reversibly binding to carbohydrates. In this work, it was possible to purify and characterize a lectin from Parkia panurensis (Leguminosae family; Mimosoideae subfamily) seeds by a combination of the techniques: protein precipitation, along with affinity and then ion exchange chromatography using the Sepharose-mannose and diethylaminoethyl matrices, respectively. The pure lectin, called PpaL, has affinity by D-mannose, D-glucose and derivatives. PpaL was stable over a wide range of temperature and pH, and it showed an SDS-PAGE profile of only one protein band with apparent mass of 45 kDa, subsequently confirmed by mass spectrometry, and presented a molecular mass of 50,566 ± 1 Da. PAGE analysis and molecular exclusion chromatography demonstrated that PpaL is presented as a dimer in solution. Partial sequencing of the primary structure resulted in a total of 334 amino acid residues with approximately 97% similarity to Parkia biglobosa and Parkia platycephala seed lectins. PpaL was shown to be toxic against Artemia nauplii and had an LC50 of 20 µg/mL. The effects of biological activities presented by these proteins make them important biotechnological tools, demonstrating the importance of bioprospection of new lectins. © 2019 Elsevier B.V
Niche overlap between two sympatric frugivorous Neotropical primates: improving ecological niche models using closely-related taxa
No full textEcological niche models (ENMs) are widely used tools for predicting species geographic distribution as a function of environmental variables. The inclusion of biotic factors in the predictor suite can significantly increase the predictive power of such models, leading to a model closer to the realized niche for the species under investigation. In this study, we provide evidence of niche overlap between gray woolly monkeys (Lagothrix cana) and black-faced black spider monkeys (Ateles chamek) based on locality and ecological data covering their complete geographic range in the Amazon forests of Brazil, Peru and Bolivia. We also estimate the potential distribution of L. cana using environmental predictors, and the distribution of A. chamek as a biotic factor. Finally, we quantified current and future habitat loss and areas under legal protection. We found that only 39% of the L. cana area of occupancy is under legal protection and that the species could potentially lose up to 58% of habitat in the next 30 years. We also show that the use of a closely-related species that has a more robust dataset can improve ENMs of poorly studied, rare and/or cryptic species. The framework developed here can be applied to a wide range of sympatric species if they share similar ecological requirements. Since our focal species are the most frugivorous primates in our study region and especially vulnerable to habitat loss, the identification of highly suitable areas for both taxa can help to protect other forest-dwelling species, reducing the rate of overall biodiversity loss. © 2020, Springer Nature B.V