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1.
An Acad Bras Cienc ; 95(1): e20211605, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37132746

RESUMO

Many biological activities are described for the Clusiaceae family. Clusia fluminensis, a species from Brazilian flora, is mainly employed for ornamental purposes. This review aimed to depict the current knowledge of C. fluminensis from a bioprospecting standpoint. "Clusia fluminensis" search term was applied in Scopus, Web of Science, PubMed and Bireme databases according to PRISMA-ScR statement. Selected papers on Phytochemistry or Bioactivity followed hand searching procedures. Bioactivity preclinical studies considered in vitro or in vivo biological systems, treated with plant extracts or isolated compounds. The outcomes were compared with standard or no treatment control groups. Critical appraisal of individual trials considered completeness in the research fields. Our results showed that 81% of the selected papers presented high level of completeness, 69% revealed phytochemical parameters and 31% biological applications of plant extracts and isolated compounds. Polyisoprenylated benzophenones, terpenoids, sterols and phenolic compounds were identified. Antiviral, insecticidal and snake antivenom activities were reported. In conclusion, the phytochemical data reinforce the reported activities. Potential applications in personal care, nutritional supplementation and pharmaceutical, food, chemical or textile industries were also identified. Toxicological and phytochemical complementary studies may be required.


Assuntos
Clusia , Clusia/química , Bioprospecção , Extratos Vegetais/química , Compostos Fitoquímicos/farmacologia , Suplementos Nutricionais
2.
Zootaxa ; 5257(1): 123-130, 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-37044617

RESUMO

The druid fly genus Clusia was firstly recorded from China, including two new species: C. luteimacula sp. nov. from Yintiaoling Nature Reserve of Chongqing and C. sinensis sp. nov. from Wanglang of Sichuan and Mt. Taibai of Shaanxi. A key to all species of Clusia globally is presented.


Assuntos
Clusia , Dípteros , Animais , Distribuição Animal , China
3.
Ann Bot ; 132(4): 739-752, 2023 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-36891814

RESUMO

Clusia is the only genus containing dicotyledonous trees with a capacity to perform crassulacean acid metabolism (CAM). Since the discovery of CAM in Clusia 40 years ago, several studies have highlighted the extraordinary plasticity and diversity of life forms, morphology and photosynthetic physiology of this genus. In this review, we revisit aspects of CAM photosynthesis in Clusia and hypothesize about the timing, the environmental conditions and potential anatomical characteristics that led to the evolution of CAM in the group. We discuss the role of physiological plasticity in influencing species distribution and ecological amplitude in the group. We also explore patterns of allometry of leaf anatomical traits and their correlations with CAM activity. Finally, we identify opportunities for further research on CAM in Clusia, such as the role of elevated nocturnal accumulation of citric acid, and gene expression in C3-CAM intermediate phenotypes.


Assuntos
Clusia , Metabolismo Ácido das Crassuláceas , Clusia/anatomia & histologia , Clusia/metabolismo , Fotossíntese/fisiologia , Folhas de Planta , Árvores
4.
Ann Bot ; 132(4): 801-810, 2023 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-36821473

RESUMO

BACKGROUND AND AIMS: Many succulent species are characterized by the presence of Crassulacean acid metabolism (CAM) and/or elevated bulk hydraulic capacitance (CFT). Both CAM and elevated CFT substantially reduce the rate at which water moves through transpiring leaves. However, little is known about how these physiological adaptations are coordinated with leaf vascular architecture. METHODS: The genus Clusia contains species spanning the entire C3-CAM continuum, and also is known to have >5-fold interspecific variation in CFT. We used this highly diverse genus to explore how interspecific variation in leaf vein density is coordinated with CAM and CFT. KEY RESULTS: We found that constitutive CAM phenotypes were associated with lower vein length per leaf area (VLA) and vein termini density (VTD), compared to C3 or facultative CAM species. However, when vein densities were standardized by leaf thickness, this value was higher in CAM than C3 species, which is probably an adaptation to overcome apoplastic hydraulic resistance in deep chlorenchyma tissue. In contrast, CFT did not correlate with any xylem anatomical trait measured, suggesting CAM has a greater impact on leaf transpiration rates than CFT. CONCLUSIONS: Our findings strongly suggest that CAM photosynthesis is coordinated with leaf vein densities. The link between CAM and vascular anatomy will be important to consider when attempting to bioengineer CAM into C3 crops.


Assuntos
Clusia , Metabolismo Ácido das Crassuláceas , Fotossíntese/fisiologia , Clusia/metabolismo , Folhas de Planta/fisiologia , Água/metabolismo
5.
New Phytol ; 238(1): 202-215, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36604855

RESUMO

The plant cuticle is an important plant-atmosphere boundary, the synthesis and maintenance of which represents a significant metabolic cost. Only limited information regarding cuticle dynamics is available. We determined the composition and dynamics of Clusia rosea cuticular waxes and matrix using 13 CO2 labelling, compound-specific and bulk isotope ratio mass spectrometry. Collodion was used for wax collection; gas exchange techniques to test for any collodion effects on living leaves. Cutin matrix (MX) area density did not vary between young and mature leaves and between leaf sides. Only young leaves incorporated new carbon into their MX. Collodion-based sampling discriminated between epicuticular (EW) and intracuticular wax (IW) effectively. Epicuticular differed in composition from IW. The newly synthetised wax was deposited in IW first and later in EW. Both young and mature leaves synthetised IW and EW. The faster dynamics in young leaves were due to lower wax coverage, not a faster synthesis rate. Longer-chain alkanes were deposited preferentially on the abaxial, stomatous leaf side, producing differences between leaf sides in wax composition. We introduce a new, sensitive isotope labelling method and demonstrate that cuticular wax is renewed during leaf ontogeny of C. rosea. We discuss the ecophysiological significance of the new insights.


Assuntos
Dióxido de Carbono , Clusia , Dióxido de Carbono/metabolismo , Clusia/metabolismo , Colódio/análise , Colódio/metabolismo , Ceras/metabolismo , Folhas de Planta/fisiologia , Epiderme Vegetal/metabolismo
6.
Plant Cell Environ ; 46(5): 1472-1488, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36624682

RESUMO

Succulence is found across the world as an adaptation to water-limited niches. The fleshy organs of succulent plants develop via enlarged photosynthetic chlorenchyma and/or achlorophyllous water storage hydrenchyma cells. The precise mechanism by which anatomical traits contribute to drought tolerance is unclear, as the effect of succulence is multifaceted. Large cells are believed to provide space for nocturnal storage of malic acid fixed by crassulacean acid metabolism (CAM), whilst also buffering water potentials by elevating hydraulic capacitance (CFT ). The effect of CAM and elevated CFT on growth and water conservation have not been compared, despite the assumption that these adaptations often occur together. We assessed the relationship between succulent anatomical adaptations, CAM, and CFT , across the genus Clusia. We also simulated the effects of CAM and CFT on growth and water conservation during drought using the Photo3 model. Within Clusia leaves, CAM and CFT are independent traits: CAM requires large palisade chlorenchyma cells, whereas hydrenchyma tissue governs interspecific differences in CFT . In addition, our model suggests that CAM supersedes CFT as a means to maximise CO2 assimilation and minimise transpiration during drought. Our study challenges the assumption that CAM and CFT are mutually dependent traits within succulent leaves.


Assuntos
Clusia , Metabolismo Ácido das Crassuláceas , Clusia/metabolismo , Folhas de Planta/metabolismo , Fotossíntese , Água/metabolismo
7.
Funct Plant Biol ; 48(7): 703-716, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33663679

RESUMO

As future climates continue to change, precipitation deficits are expected to become more severe across tropical ecosystems. As a result, it is important that we identify plant physiological traits that act as adaptations to drought, and determine whether these traits act synergistically or independently of each other. In this study, we assessed the role of three leaf-level putative adaptations to drought: crassulacean acid metabolism (CAM), the turgor loss point (TLPΨ) and water storage hydrenchyma tissue. Using the genus Clusia as a model, we were able to explore the extent to which these leaf physiological traits co-vary, and also how they contribute to species' distributions across a precipitation gradient in Central and South America. We found that CAM is independent of the TLPΨ and hydrenchyma depth in Clusia. In addition, we provide evidence that constitutive CAM is an adaptation to year-long water deficits, whereas facultative CAM appears to be more important for surviving acute dry seasons. Finally, we find that the other leaf traits tested did not correlate with environmental precipitation, suggesting that the reduced transpirational rates associated with CAM obviate the need to adapt the TLPΨ and hydrenchyma depth in this genus.


Assuntos
Clusia , Metabolismo Ácido das Crassuláceas , Ecossistema , Fotossíntese , América do Sul
8.
Fitoterapia ; 149: 104760, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33075410

RESUMO

Three new caged polyprenylated benzophenone derivatives named burlemarxiones D-F (1-3) were isolated from the hexane extract of Clusia burle-marxii trunks. Burlemarxione D (1) contains the tetracyclo[8.3.1.03,11.05,10]tetradecane core skeleton also observed for burlemarxione A, its probable immediate precursor. However, two additional rings are formed to produce an unprecedented complex-caged core skeleton. These additional rings could be formed by a radical cyclization reaction of one prenyl group at C-5 with C-1 and C-33, followed by oxidative dehydrogenation (rearomatization) or by an intramolecular [4 + 2] radical cycloaddition (Diels-Alder reaction), followed by an enolization reaction (rearomatization). Burlemarxiones E and F were isolated after methylation with diazomethane that was necessary to avoid the interconversion of the pair of ß-diketones in tautomeric equilibrium. The proposed biosynthetic pathway for burlemarxiones D-F involves the condensation of either lavandulyl pyrophosphate or 2-(1-methylvinyl)-hexa-5-enyl pyrophosphate with the acylphloroglucinol derivative 6-benzoyl-5-hydroxy-5-cyclohexen-1,3-dione, followed by consecutive prenylation reactions. Therefore, Clusia burle-marxii reinforces the claim that the genus Clusia is an important source of sophisticated caged polyprenylated benzophenone derivatives.


Assuntos
Benzofenonas/química , Clusia/química , Benzofenonas/isolamento & purificação , Brasil , Estrutura Molecular , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Prenilação
9.
Braz. arch. biol. technol ; 63: e20190674, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1132236

RESUMO

Abstract Clusia grandiflora belongs to an important botanical family which is known for its medicinal value, however there are few reports in literature about the species, highlighting the relevance of this study. Anatomical studies with leaves and stems were performed using traditional techniques. In this investigation it was identified particularities of the species such as the presence of vascular system arranged in an opened arc-shaped with the flexed ends towards the inside of the arch with accessory bundles in the petiole. In histochemical studies, performed with different reagents, alkaloids, phenols substances, carbohydrates and lipids were located. The cytotoxic activity of the extracts was performed by tetrazole salt and showed promising results for ethanolic extracts of stems (IC50 human colon cells of 24.30 μg/ mL) and leaves (IC50 ascites gastric cells of 44.15 μg/ mL), without cell membrane disruption of erythrocytes. The antibacterial activity was evaluated by tryptic soy agar and minimal inhibitory concentration assays and showed positive results for Pseudomonas aeruginosa and Escherichia coli, with better result for adventitious roots (32 μg/ mL and 16 μg/ mL, respectively), stems (64 μg/ mL and 32 μg/ mL, respectively) and leaves (64 μg/ mL and 32 μg/ mL, respectively) ethanolic extracts. Thus, these studies were able to characterize the species and show its potential as promising source of active substances.


Assuntos
Extratos Vegetais/farmacologia , Clusia/anatomia & histologia , Clusia/química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Antibacterianos/farmacologia , Testes de Toxicidade , Linhagem Celular Tumoral , Dose Letal Mediana , Antibacterianos/isolamento & purificação
10.
Fitoterapia ; 138: 104346, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31465815

RESUMO

Three new polyprenylated benzophenone derivatives (1-3) were identified in the hexane extract of Clusia burle-marxii trunks, through the isolation and structural elucidation of their methyl derivatives, along with two known polyprenylated benzophenone derivatives sampsonine N (4) and obdeltifolione C (5). Burlemarxiones A (1) and B (2) show an unprecedent tetracyclo[8.3.1.03,11.05,10]tetradecane core skeleton. These compounds are a pair of ß-diketones in tautomeric equilibrium, whereas isonemorosonol (3) is the respective ß-diketone pair in tautomeric equilibrium with nemorosonol. Burlemarxione A methyl derivative (1a) and sampsonine N exhibited strong in vitro cytotoxic activity against GL-15 glioblastoma-derived human cell line.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Benzofenonas/farmacologia , Clusia/química , Antineoplásicos Fitogênicos/isolamento & purificação , Benzofenonas/isolamento & purificação , Brasil , Linhagem Celular Tumoral , Glioblastoma/tratamento farmacológico , Humanos , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia
11.
Curr Top Med Chem ; 19(22): 1990-2002, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31339072

RESUMO

BACKGROUND: In Brazil, the Bothrops genus accounts for 87% of registered snakebites, which are characterized by hemorrhage, tissue necrosis, hemostatic disturbances, and death. The treatment recommended by governments is the administration of specific antivenoms. Although antivenom efficiently prevents venom-induced lethality, it has limited efficacy in terms of preventing local tissue damage. Thus, researchers are seeking alternative therapies able to inhibit the main toxic effects of venoms, without compromising safety. OBJECTIVE: The study aimed to test the ability of aqueous extracts of leaves, stems, and fruits of the plant Clusia fluminensis to neutralize some toxic effects induced by the venoms of Bothrops jararaca and Bothrops jararacussu. METHODS: The plant extracts were incubated with venoms for 30 min. at 25 °C, and then in vitro (coagulant and proteolytic) and in vivo (hemorrhagic, myotoxic, and edematogenic) activities were evaluated. In addition, the extracts were administered to animals (by oral, intravenous or subcutaneous routes) before or after the injection of venom samples, and then hemorrhage and edema assays were performed. In addition, a gel solution of the fruit extract was produced and tested in terms of reducing hemorrhage effects. A chemical prospection was performed to identify the main classes of compounds present in the extracts. RESULTS: All the extracts inhibited the activities of the two venoms, regardless of the experimental protocol or route of administration of the extracts. Moreover, the gel of the fruit extract inhibited the venom-induced-hemorrhage. The extracts comprised of tannins, flavonoids, saponins, steroids, and terpenoids. CONCLUSION: Antivenom properties of C. fluminensis extracts deserve further investigation in order to gain detailed knowledge regarding the neutralization profile of these extracts.


Assuntos
Antivenenos/farmacologia , Clusia/química , Extratos Vegetais/farmacologia , Venenos de Serpentes/antagonistas & inibidores , Animais , Antivenenos/química , Antivenenos/isolamento & purificação , Bothrops , Brasil , Frutas/química , Hemorragia/tratamento farmacológico , Camundongos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Caules de Planta/química , Venenos de Serpentes/toxicidade
12.
Plant Biol (Stuttg) ; 21(4): 753-761, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30620429

RESUMO

Cockroaches have rarely been documented as pollinators. In this paper we examine whether this is because they might be inefficient at pollination compared to other pollinators. Clusia blattophila, a dioecious shrub growing on isolated rocky outcrops in French Guiana, is pollinated by Amazonina platystylata cockroaches and provides a valuable system for the study of cockroach pollination efficiency. We examined the species composition of the visitor guild and visitation rates by means of camcorder recordings and visitor sampling. Then, we investigated the capacity for pollen transfer of principal visitors and found correlations between visitation rates and pollen loads on stigmas. In an exclusion experiment we determined the contributions of individual species to pollination success. Amazonina platystylata, crickets and two species of Diptera transferred pollen, but the number of transferred pollen grains was only related to visitation rates in the case of cockroaches. Crickets visited and rarely carried pollen. Dipterans were as frequent as cockroaches, carried similar pollen loads, but transferred much less pollen. An estimated 41% and 17% of ovules were pollinated by cockroaches and dipterans, respectively. The remaining ovules were not pollinated. There was no spatial variation in pollinator guild composition, but cockroaches visited flowers less frequently at the smaller study site. We demonstrate that cockroaches pollinate a large proportion of ovules. Their pollination service is not confined to one study site and, unlike that provided by dipterans, is not limited to certain years. We suggest that cockroach pollination has been overlooked and that cockroach-pollinated plants, which share certain floral features, possess adaptations to pollination by cockroaches.


Assuntos
Clusia/fisiologia , Baratas , Polinização , Animais , Clusia/anatomia & histologia , Baratas/fisiologia , Dípteros/fisiologia , Flores/anatomia & histologia , Flores/fisiologia , Guiana Francesa , Gryllidae/fisiologia , Polinização/fisiologia
13.
Environ Sci Pollut Res Int ; 24(36): 28026-28035, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28994038

RESUMO

The objectives of this work were to evaluate if the pollution emitted by the pelletizing factory causes visual symptoms and/or anatomical changes in exposed Eugenia uniflora and Clusia hilariana, in active biomonitoring, at different distances from a pelletizing factory. We characterize the symptomatology, anatomical, and histochemistry alterations induced in the two species. There was no difference in the symptomatology in relation to the different distances of the emitting source. The foliar symptoms found in C. hilariana were chlorosis, necrosis, and foliar abscission and, in E. uniflora, were observed necrosis punctuais, purple spots in the leaves, and increase in the emission of new leaves completely purplish. The two species presented formation of a cicatrization tissue. E. uniflora presented reduction in the thickness of leaf. In C. hilariana, it was visualized hyperplasia of the cells and the adaxial epidermis did not appear collapsed due to thick cuticle and cuticular flanges. Leaves of C. hilariana showed positive staining for iron, protein, starch, and phenolic compounds. E. uniflora showed positive staining for total phenolic compounds and starch. Micromorphologically, there was accumulation of particulate matter on the leaf surface, obstruction of the stomata, and scaling of the epicuticular wax in both species. It was concluded that the visual and anatomical symptoms were efficient in the diagnosis of the stress factor. C. hilariana and E. uniflora showed to be good bioindicators of the atmospheric pollutants emitted by the pelletizing factory.


Assuntos
Poluentes Atmosféricos/análise , Clusia/efeitos dos fármacos , Biomarcadores Ambientais/efeitos dos fármacos , Monitoramento Ambiental/métodos , Eugenia/efeitos dos fármacos , Indústrias , Material Particulado/análise , Poluentes Atmosféricos/toxicidade , Brasil , Clusia/metabolismo , Eugenia/metabolismo , Ferro , Material Particulado/toxicidade , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo
14.
An. acad. bras. ciênc ; 89(3): 1565-1578, July-Sept. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-886746

RESUMO

ABSTRACT This study aims the anatomical description and chemical characterization of aerial parts of Clusia criuva Cambess., Clusiaceae in addition to the evaluation of the antioxidant activity of crude extracts, correlated to the flavonoid content. The morphological characterization was performed using traditional techniques of plant anatomy. For phytochemical studies, crude extracts were obtained by static maceration and analyzed by thin layer chromatography. The antioxidant activity and the flavonoids content were determined by colorimetric methods involving, respectively, 2,2-diphenyl-1-picrylhydrazyl free radical and aluminum chloride. C. criuva has uniseriate epidermis, paracytic stomata, hypostomatic leaves, cuticular flanges and cordiform vascular cylinder with accessory bundles. Chemical prospecting confirmed the abundant presence of terpenes and phenols in the extracts of leaves and of fruits. The methanolic extract of seeds showed the lowest EC50 value, but the methanolic extract of pericarps exhibited the highest maximum antioxidant activity. The results suggested a high percentage of flavonoids in the hexanic extract of pericarps, however, this could represent, in fact, the presence of benzophenones. Secretory ducts and the shape of the midrib are diagnostic for C. criuva. The antioxidant activity is not directly related to the flavonoids. The results indicate the importance of future studies with C. criuva chemical constituents.


Assuntos
Extratos Vegetais/química , Clusia/química , Antioxidantes/química , Microscopia Eletrônica de Varredura , Cromatografia em Camada Delgada , Colorimetria , Folhas de Planta/ultraestrutura , Folhas de Planta/química , Clusia/classificação , Clusia/ultraestrutura , Antioxidantes/isolamento & purificação
15.
An Acad Bras Cienc ; 89(3): 1565-1578, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28767887

RESUMO

This study aims the anatomical description and chemical characterization of aerial parts of Clusia criuva Cambess., Clusiaceae in addition to the evaluation of the antioxidant activity of crude extracts, correlated to the flavonoid content. The morphological characterization was performed using traditional techniques of plant anatomy. For phytochemical studies, crude extracts were obtained by static maceration and analyzed by thin layer chromatography. The antioxidant activity and the flavonoids content were determined by colorimetric methods involving, respectively, 2,2-diphenyl-1-picrylhydrazyl free radical and aluminum chloride. C. criuva has uniseriate epidermis, paracytic stomata, hypostomatic leaves, cuticular flanges and cordiform vascular cylinder with accessory bundles. Chemical prospecting confirmed the abundant presence of terpenes and phenols in the extracts of leaves and of fruits. The methanolic extract of seeds showed the lowest EC50 value, but the methanolic extract of pericarps exhibited the highest maximum antioxidant activity. The results suggested a high percentage of flavonoids in the hexanic extract of pericarps, however, this could represent, in fact, the presence of benzophenones. Secretory ducts and the shape of the midrib are diagnostic for C. criuva. The antioxidant activity is not directly related to the flavonoids. The results indicate the importance of future studies with C. criuva chemical constituents.


Assuntos
Antioxidantes/química , Clusia/química , Extratos Vegetais/química , Antioxidantes/isolamento & purificação , Cromatografia em Camada Delgada , Clusia/classificação , Clusia/ultraestrutura , Colorimetria , Microscopia Eletrônica de Varredura , Folhas de Planta/química , Folhas de Planta/ultraestrutura
16.
Integr Comp Biol ; 56(1): 85-97, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27371561

RESUMO

Most tropical ectotherms live near their physiological limits for temperature. Substantial ecological effects of global change are predicted in the tropics despite the low amplitude of temperature change. These predictions assume that tropical ectotherms experience air temperature as measured by weather stations or predicted by global circulation models. The body temperature of ectotherms, however, can deviate from ambient air when the organism samples the mosaic of microclimates at fine scales. The thermal heterogeneity of tropical landscapes has been quantified only rarely in comparison to temperate habitats, limiting our ability to infer the vulnerability to warming of tropical ectotherms. Here, we used thermal imaging to quantify the heterogeneity in surface temperatures across spatial scales, from the micro- up to landscape scale, at the top of an Inselberg in French Guiana. We measured the thermal heterogeneity at the scale of Clusia nemorosa leaves, by categorizing leaves in full sun versus leaves in the shade to quantify the microclimatic variance available to phytophagous insects. Then, we measured the thermal heterogeneity at the scales of the single shrub and the landscape, for several sites differing in their orientation toward the sun to quantify the microclimatic heterogeneity available for larger ectotherms. All measurements were made three times per day over four consecutive days. There was a high level of thermal heterogeneity at all spatial scales. The thermal variance varied between scales, increasing from the within-leaf surface to the landscape scale. It also shifted across the day in different ways depending on the spatial scale. Then, using a set of published data, we compared the critical temperature (CTmax) of neo-tropical ectotherms and temperature distributions. The portion of space above the CTmax varied substantially depending on spatial scale and taxa. Insects were particularly at risk at the surface of leaves exposed to solar radiation but not on shaded leaves. By contrast, ants tolerated elevated surface temperatures and can survive almost anywhere in the habitat. We suggest that the fine scale mosaic of microclimates in the tropics modulates the vulnerability of ectotherms to warming. By moving just a few meters, or even a few centimeters, small tropical ectotherms can radically change their microclimatic temperature and escape overheating.


Assuntos
Anfíbios/fisiologia , Mudança Climática , Temperatura Alta , Insetos/fisiologia , Microclima , Répteis/fisiologia , Animais , Formigas/fisiologia , Clusia/fisiologia , Guiana Francesa , Folhas de Planta/fisiologia , Temperatura , Clima Tropical
17.
Rev. cuba. plantas med ; 21(1)jan.-mar. 2016. tab
Artigo em Português | LILACS | ID: lil-781967

RESUMO

Introduction: the fast development of drug resistance and the slowdown of the development of new active drugs, drew attention to the treatment with the drug combination. Objective: to analyze the antimicrobial activity of the ethanol extract of Cluisa nemorosa (Clusiaceae) against multiresistant strains and standards as well as the modulating action with aminoglycoside amikacin, gentamicin and neomycin. Methods: the plant material (leaves) was collected in Araripe, crushed and put into ethanol 96 % as solvent. Distillation of the solvent was then performed in a rotary evaporator to produce the gross ethanol extrato. A microdilution assay was conducted to verify antibacterial activity and the possible interactions of aminoglycosides associated with the study samples. A sub-inhibitory concentration of 128 µg/mL (Minimum Inhibitory concentration/8) was used. Results: the activity of the extract against the strains isolated patterns had an Minimum Inhibitory concentration > 1024 mg/mL, the action of antibiotics was modulated synergistically by the extract against multidrug-resistant Gram-positive bacteria Staphylococcus aureus and Gram-negative Escherichia coli and Pseudomonas aeruginosa. Conclusions: the synergism of the ethanol extract was verified by microdilution method. Therefore, it is suggested that the extract of Clusia nemorosa be used as a source of natural products for antimicrobial therapy and to combat bacterial multidrug resistance(AU)


Introducción: el rápido desarrollo de resistencia de las drogas y la relentización en el desarrollo de nuevas drogas activas llaman la atención al tratamiento de combinación de drogas. Objetivos: analizar la actividad antimicrobiana del extracto etanólico de Clusia nemorosa (Clusiaceae) frente a cepas multirresistentes y normas, así como la acción modulante con aminoglucósido amikacina, gentamicina y la neomicina. Métodos: el material vegetal (hojas), colectado en el Araripe, fue triturado y sumergido en etanol 96 percent como solvente. De inmediato, fue sometido a destilación del solvente en un evaporador rotativo para la producción de lo extrato etanólico bruto. Se llevó a cabo un ensayo de microdilución para verificar la actividad antibacteriana y las posibles interacciones de aminoglucósidos asociados con las muestras estudiadas, se utilizó una concentración sub-inhibitoria de 128 µg/mL (Concentración mínima inhibitoria/8). Resultados: la actividad del extracto frente a las cepas aisladas patrones tenía una Concentración mínima inhibitoria> 1024mg/mL; la acción de los antibióticos fue modulada por el extracto de forma sinérgica contra multirresistente Gram-positivo Staphylococcus aureus y bacterias Gram-negativas Escherichia coli y Pseudomonas aeruginosa. El sinergismo del extracto de etanol se verificó mediante el método de microdilución. Conclusiones: el extracto de las hojas de C. nemorosa actuaron como un agente modulador. Se sugiere que el extracto de C. nemorosa puede ser utilizado como una fuente de productos naturales en la terapia antimicrobiana y en el combate de la resistencia a múltiples fármacos bacterianos(AU)


Introdução: o rápido desenvolvimento de resistência às drogas e a desaceleração no desenvolvimento de novas drogas ativas, chamaram a atenção para o tratamento com combinação de drogas. Objetivos: analisar a atividade antimicrobiana do extrato etanólico de Clusia nemorosa (Clusiaceae) frente a cepas padrões e multirresistentes bem como a ação moduladora com aminoglicosídeos amicacina, neomicina e gentamicina. Métodos: o material vegetal (folhas), coletado na Chapada do Araripe, foi triturado e submerso em solvente etanol 96 por cento e submetido à destilação do solvente no aparelho evaporador rotativo para a produção do extrato etanólico bruto. Um ensaio de microdiluição foi realizado para verificar a atividade antibacteriana e as possíveis interações dos aminoglicosídeos associados às amostras estudadas, utilizando uma concentração sub-inibitória de 128 µg/mL (concentração inibitória mínima/8). Resultados: a ação do extrato isolado frente às cepas padrões teve uma concentração inibitória mínima > 1024 µg/mL, a ação dos antibióticos foi modulada sinergicamente pelo extrato contra as bactérias multirresistentes Gram-positiva Staphylococcus aureus e Gram-negativas Escherichia coli e Pseudomonas aeruginosa. Conclusões: o extrato das folhas de C. nemorosa atuou como um agente modulador da atividade antimicrobiana. É sugerido que o extrato de Clusia nemorosa pode ser utilizado como uma fonte de produtos naturais na terapêutica antimicrobiana e no combate a multirresistência bacteriana(AU)


Assuntos
Humanos , Preparações de Plantas/uso terapêutico , Clusia , Anti-Infecciosos/uso terapêutico
18.
Braz J Microbiol ; 46(4): 1027-35, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26691460

RESUMO

We investigated the composition and structure of fungal communities associated with leaf litter generated by Clusia nemorosa and Vismia guianensis that belong to phylogenetically-related botanical families and exist together in a remnant of the Atlantic Forest in Bahia, Brazil. Samplings were conducted during wet (June 2011) and dry (January 2013) seasons in Serra da Jibóia. The fungi were isolated using particle filtration and the 1,832 isolates represented 92 taxa. The wet season yielded the largest number of isolates (1,141) and taxa (76) compared with the dry season (641 isolates and 37 taxa). The richness and diversity of fungal species associated with C. nemorosa (64 taxa, Simpson=0.95)were higher compared with those of V.guianensis (59 taxa, Simpson =0.90). Analysis of similarity (ANOSIM) revealed significant variations in the composition and community structure of fungi isolated from the two plants as a function of seasons. In contrast, nonmetric multidimensional scaling (NMDS) analysis show that the seasonality was an important influence on the distribution of fungal species. However, the populations of the saprobic fungal communities were dynamic, and several factors may influence such communities in the Atlantic Forest.


Assuntos
Clusia/microbiologia , Clusiaceae/microbiologia , Fungos/isolamento & purificação , Folhas de Planta/microbiologia , Brasil , Ecossistema , Florestas , Fungos/classificação , Fungos/genética , Estações do Ano , Árvores/microbiologia
19.
Braz. j. microbiol ; 46(4): 1027-1035, Oct.-Dec. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-769635

RESUMO

Abstract We investigated the composition and structure of fungal communities associated with leaf litter generated by Clusia nemorosa and Vismia guianensis that belong to phylogenetically-related botanical families and exist together in a remnant of the Atlantic Forest in Bahia, Brazil. Samplings were conducted during wet (June 2011) and dry (January 2013) seasons in Serra da Jibóia. The fungi were isolated using particle filtration and the 1,832 isolates represented 92 taxa. The wet season yielded the largest number of isolates (1,141) and taxa (76) compared with the dry season (641 isolates and 37 taxa). The richness and diversity of fungal species associated with C. nemorosa (64 taxa, Simpson=0.95)were higher compared with those of V.guianensis (59 taxa, Simpson =0.90). Analysis of similarity (ANOSIM) revealed significant variations in the composition and community structure of fungi isolated from the two plants as a function of seasons. In contrast, nonmetric multidimensional scaling (NMDS) analysis show that the seasonality was an important influence on the distribution of fungal species. However, the populations of the saprobic fungal communities were dynamic, and several factors may influence such communities in the Atlantic Forest.


Assuntos
Brasil/classificação , Brasil/genética , Brasil/isolamento & purificação , Brasil/microbiologia , Clusia/classificação , Clusia/genética , Clusia/isolamento & purificação , Clusia/microbiologia , Clusiaceae/classificação , Clusiaceae/genética , Clusiaceae/isolamento & purificação , Clusiaceae/microbiologia , Ecossistema/classificação , Ecossistema/genética , Ecossistema/isolamento & purificação , Ecossistema/microbiologia , Florestas/classificação , Florestas/genética , Florestas/isolamento & purificação , Florestas/microbiologia , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Fungos/microbiologia , Folhas de Planta/classificação , Folhas de Planta/genética , Folhas de Planta/isolamento & purificação , Folhas de Planta/microbiologia , Estações do Ano/classificação , Estações do Ano/genética , Estações do Ano/isolamento & purificação , Estações do Ano/microbiologia , Árvores/classificação , Árvores/genética , Árvores/isolamento & purificação , Árvores/microbiologia
20.
Mem. Inst. Oswaldo Cruz ; 110(5): 629-635, Aug. 2015. ilus
Artigo em Inglês | LILACS | ID: lil-755896

RESUMO

Studies evaluated the effects of hexanic extracts from the fruits and flowers ofClusia fluminensis and the main component of the flower extract, a purified benzophenone (clusianone), against Aedes aegypti. The treatment of larvae with the crude fruit or flower extracts from C. fluminensis did not affect the survival ofAe. aegypti (50 mg/L), however, the flower extracts significantly delayed development of Ae. aegypti. In contrast, the clusianone (50 mg/L) isolate from the flower extract, representing 54.85% of this sample composition, showed a highly significant inhibition of survival, killing 93.3% of the larvae and completely blocking development of Ae. aegypti. The results showed, for the first time, high activity of clusianone against Ae. aegypti that both killed and inhibited mosquito development. Therefore, clusianone has potential for development as a biopesticide for controlling insect vectors of tropical diseases. Future work will elucidate the mode of action of clusianone isolated from C. fluminensis.

.


Assuntos
Animais , Aedes/efeitos dos fármacos , Clusia/química , Insetos Vetores/efeitos dos fármacos , Larva/efeitos dos fármacos , Extratos Vegetais/farmacologia , Fatores de Tempo
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