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1.
Nat Prod Res ; 38(4): 614-618, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-36924455

RESUMO

The objective of this study was to conduct chemical analyses of bioactive compounds found in the bark and leaves of Humiria balsamifera (Aubl.) A. St. Hil. and Hymenaea courbaril L. Chemical screening was performed to detect the presence of secondary metabolites. Quantification of the concentrations of phenolic compounds, anthocyanins, flavonoids, and antioxidants was performed by ultraviolet spectrophotometry through recommended methodologies. Extracts of the leaves of Humiria balsamifera (Aubl.) A. St. Hil. were found to have high concentrations of flobabénic tannins. Tannins, flavonoids, flavonols, flavonones, flavanonols, xanthones, steroids, and saponins were also found in bark extracts of the same species. The plant species Humiria balsamifera (Aubl.) A. St. Hil. and Hymenaea courbaril L. showed potential for antioxidant activity and for use in the pharmacological and food industries.


Assuntos
Antioxidantes , Hymenaea , Antioxidantes/farmacologia , Taninos , Hymenaea/química , Antocianinas , Extratos Vegetais/química , Flavonoides/farmacologia
2.
Braz. j. biol ; 82: 1-9, 2022. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468519

RESUMO

Hymenaea martiana is a species popularly known in Northeastern Brazil as "jatobá" and used in folk medicine to treat pain and inflammation. The aim of this work was to evaluate the antinociceptive and anti-inflammatory activity of H. martiana. In the present study, we carried out an investigation about the effects of the crude ethanolic extract (Hm-EtOH) and the ethyl acetate fraction (Hm-AcOEt) in models of nociception and inflammation in mice. Chemical (acetic acid-induced writhing and formalin) and thermal stimuli (hot plate) were used for the evaluation of antinociceptive activity, while for the anti-inflammatory profile paw edema induced by carrageenan was used, along with leukocyte migration to the peritoneal cavity. The presence of the flavonoid astilbin in the samples was characterized through HPLC-DAD-MS analysis. Hm-EtOH and Hm-AcOEt (100, 200 and 400 mg.kg-¹, i.p.) significantly reduced the number of abdominal contortions and decreased the paw licking time in the formalin test. In the hot plate, the extract increased the latency time of animals. Hm-EtOH and Hm-AcOEt inhibited significantly the increase in the edema after the administration of carrageenan. Hm-EtOH and Hm-AcOEt inhibited leukocyte migration in the peritonitis test. HPLC-DAD-MS analysis of Hm-EtOH and Hm-AcOEt revealed the presence of the flavonoid astilbin in the samples. According to the results of this study, both Hm-EtOH and Hm-AcOEt have antinociceptive and anti-inflammatory activities, which could be related with the presence of flavonoid in the extracts. The results reinforce the popular use of this plant.


Hymenaea martiana é uma espécie popularmente conhecida no Nordeste do Brasil como “jatobᔠe usada na medicina popular para tratar a dor e a inflamação. O objetivo deste trabalho foi avaliar a atividade antinociceptiva e anti inflamatória de H. martiana. No presente estudo, foram avaliados os efeitos do extrato etanólico bruto (Hm-EtOH) e da fração acetato de etila (Hm-AcOEt) em modelos de nocicepção e inflamação em camundongos. Foram utilizados estímulos químicos (contorções abdominais induzidas por ácido acético e teste da formalina) e estímulo térmico (teste da placa quente) para avaliação da atividade antinociceptiva, enquanto no perfil anti-inflamatório foi utilizado o teste do edema de pata induzido por carragenina e migração de leucócitos para a cavidade peritoneal. A presença do flavonoide astilbina nas amostras foi caracterizada através de análise por CLAE-DAD-EM. Hm-EtOH e o Hm-AcOEt (100, 200 e 400 mg.kg-¹, i.p.) reduziram significativamente o número de contorções abdominais e diminuíram o tempo de lambida da pata no teste da formalina. No teste da placa quente, houve aumento do tempo de latência dos animais. Hm-EtOH e Hm-AcOEt inibiram significativamente o aumento do edema após a administração de carragenina, bem como inibiram a migração de leucócitos no teste de peritonite. A análise por CLAE-DAD-EM de Hm-EtOH e Hm-AcOEt revelou a presença do flavonoide astilbina nas amostras. De acordo com os resultados deste estudo, tanto Hm-EtOH quanto o Hm-AcOEt possuem atividades antinociceptiva e anti-inflamatória, o que pode estar relacionado à presença do flavonoide. Os resultados reforçam o uso popular desta planta.


Assuntos
Animais , Camundongos , Anti-Inflamatórios/análise , Hymenaea/química , Plantas Medicinais/efeitos adversos
3.
Rev. chil. nutr ; 47(3): 366-371, jun. 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1126133

RESUMO

Jatobá (Hymenaea sp.) is an arboreal legume native to the Brazilian Savannah (Cerrado) and its fruit has a high functional potential, but the jatobá-da-mata specie has been poorly explored. This study evaluated the nutritional profile, bioactive compounds and antioxidant capacity of jatobá-da-mata byproducts: pulp flour, fibrous pulp residue and sap. Jatobá fruits were pulped to obtain pulp flour and fibrous pulp residue, and the jatobá tree's sap was obtained in a typical extraction location in the Cerrado (Brazilian Savannah). Fibrous pulp residue and pulp flour had high protein (11 and 12 g/100 g) and dietary fiber (49 and 44 g/100 g) content, respectively, and the fibrous residue showed the highest total and insoluble fibers, ash and vitamin C content. Regarding polyphenols, the fibrous residue showed a high concentration (775 mg GAE/100 g); an intermediate value in pulp flour (462 mg GAE/100 g); and considerable content in sap(181 mg GAE/100 g). Jatobá residue and pulp flour are suitable ingredients for the formulation of functional foods, and the sap is a promising non-caloric product with potential health benefits.


Jatobá (Hymenaea sp.) es una leguminosa arbórea originaria de la sabana brasileña y su fruto tiene un alto potencial funcional, pero la especie jatobá-da-mata ha sido poco explorada. El objetivo del estudio fue evaluar el perfil nutricional, compuestos bioactivos y capacidad antioxidante de subproductos del jatobá-da-mata: harina de la pulpa, residuo fibroso de la pulpa y la savia. Los frutos fueron despulpados para obtener la harina juntamente con el residuo fibroso de la pulpa, y la savia de la planta fue obtenida en un lugar exclusivo de extracción en el Cerrado (Sábana brasileña). El residuo fibroso y la harina de la pulpa contienen un alto contenido de proteína (11 y 12 g/100 g) y de fibra dietética (49 y 44 g/100 g), respectivamente, y el residuo fibroso mostró el mayor contenido de fibras totales y insolubles, cenizas y vitamina C. En cuanto a los polifenoles, el residuo fibroso presentó alta concentración (775 mg AGE/100 g); la harina de la pulpa, un valor intermedio (462 mg AGE/100 g); y la savia, un contenido considerable (181 mg AGE/100 g). El residuo fibroso y la harina de la pulpa son ingredientes adecuados en la formulación de alimentos funcionales, y la savia es un producto no calórico prometedor con potenciales beneficios a la salud.


Assuntos
Hymenaea/química , Antioxidantes/química , Ácido Ascórbico/análise , Fibras na Dieta/análise , Compostos Fenólicos/análise , Compostos Fitoquímicos , Farinha
4.
J Ethnopharmacol ; 247: 112265, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31580941

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Hymenaea cangaceira Pinto, Mansano & Azevedo (Fabaceae) is a Brazilian medicinal plant widely known as "Jatobá". In folk medicine, it is used to treat infections, respiratory problems, rheumatism, antitumoral, inflammation and pain, however, no activity has been scientifically validated. AIM OF THE STUDY: This study investigated chemical composition of essential oil from Hymenaea cangaceira (EOHc), antimicrobial, antinociceptive and antioxidant activities besides protection against DNA damage and hemolysis. MATERIAL AND METHODS: The essential oil was obtained by hydrodistillation, and characterized by GC-MS and GC-FID. The evaluation of antimicrobial activity was performed by microdilution method. The evaluation of the antioxidant activity was performed using the radicals DPPH, ABTS, O2- and OH-, and the protection of DNA damage using plasmid pBR322. Different experimental models were used to evaluate the antinociceptive effect (acetic acid and formalin), and evaluate the mechanisms of action involved with pharmacological antagonists (naloxone, atropine and gibenclamide) in mice. The essential oil was evaluated for hemolysis on human erythrocytes. RESULTS: The extraction of EOHc showed a yield of 0.18% on a dry basis, presenting high content of hydrocarbon sesquiterpenes (79.04%), high antioxidant activity and protect DNA from damage, besides presenting antifungal and antibacterial activity against Gram-positive and Gram-negative bacteria in vitro. It was found that the essential oil had no acute toxicity in mice up to 5000 mg/kg oral administration (o.a.), in addition to no hemolysis on human erythrocytes. The reduction of antinociceptive activity was 75%, with the opioid system as the mechanism of action. CONCLUSION: Our results validate the main activities by the traditional use attributed to H. cangaceira for antimicrobial and analgesic activity. In addition, the oil has a potent antioxidant activity, protecting the body against oxidative stress damage, adding new value to an endemic species not known to the industry.


Assuntos
Analgésicos/farmacologia , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Hymenaea/química , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Ácido Acético/toxicidade , Analgésicos/química , Analgésicos/isolamento & purificação , Animais , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Brasil , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Etanol/química , Etnofarmacologia , Formaldeído/toxicidade , Humanos , Medicina Tradicional/métodos , Camundongos , Testes de Sensibilidade Microbiana , Nociceptividade/efeitos dos fármacos , Óleos Voláteis/química , Óleos Voláteis/uso terapêutico , Dor/induzido quimicamente , Dor/diagnóstico , Dor/tratamento farmacológico , Medição da Dor , Óleos de Plantas/química , Óleos de Plantas/isolamento & purificação , Testes de Toxicidade Aguda
5.
An Acad Bras Cienc ; 91(4): e20180446, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31800695

RESUMO

Hymenaea courbaril has been used to treat different diseases, although its properties are yet to be scientifically validated. The objective of this study was to determine the cytotoxicity, genotoxicity, antigenotoxicity and antioxidant potentials of hydroethanolic extract from H. courbaril seeds. Therefore, for the cytotoxicity test an anti-melanoma assay was performed in B16F10 strain cells. The genotoxicity and antigenotoxicity was evaluated in bone marrow cells (Permit number: 002/2010) of mice, the antioxidant activity was determined by the DPPH test and the total flavonoid content was also determined. The hydroethanolic extract showed antigenotoxic effect and antioxidant activity. It was verified that total flavonoid content was 442.25±18.03 mg RE/g dry extract. HPLC-PAD chromatogram revealed presence of flavones as majority compound in evaluated extract. The results allowed us to also infer that the hydroethanolic extract from seeds shows cytotoxic activity against B16F10 melanoma cells line and it has dose-and-time-dependency.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Células da Medula Óssea/efeitos dos fármacos , Hymenaea/química , Melanoma/patologia , Extratos Vegetais/farmacologia , Animais , Antineoplásicos Fitogênicos/isolamento & purificação , Antioxidantes/isolamento & purificação , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Dano ao DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Masculino , Camundongos , Testes para Micronúcleos
6.
Pesqui. vet. bras ; 38(3): 462-469, mar. 2018. tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-964900

RESUMO

Este estudo objetivou avaliar a ação antimicrobiana e antisséptica do extrato etanólico bruto da folha da Hymenaea martiana (Jatobá). O estudo foi realizado no Laboratório de Microbiologia e Imunologia da UNIVASF, na cidade de Petrolina-PE. Os extratos foram preparados utilizando diferentes diluentes, sendo estes: álcool etílico absoluto e a água destilada. Em seguida, foi empregada a técnica da Concentração Inibitória Mínima (MIC) e da Concentração Bactericida Mínima (CBM). Todos os ensaios foram realizados em triplicata. A CBM média do extrato diluído em etanol foi de 358µg/µL e do extrato diluído em água destilada foi igual a 520,82µg/mL. Não houve diferença (P<0,05) quanto à inibição bacteriana para o extrato diluído em álcool etílico absoluto ou água destilada autoclavada. Ao comparar a atividade do extrato diluído em álcool etílico absoluto e a relação com a presença do gene blaZ, observou-se que os isolados negativos para o gene pesquisado apresentaram uma CBM igual a 412,3µg/mL, e, quando comparadas aos que foram positivos para o gene blaZ, que foi de 308,80µg/mL, contudo sem diferença estatística. Quanto à inibição das bactérias utilizando extrato aquoso, a atividade foi igual para as bactérias com ou sem o gene (520,82µg/mL). Desse modo, tanto o extrato diluído em álcool etílico absoluto quanto em agua destilada autoclavada demonstrou atividade antimicrobiana, sugerindo que ocorreu extração de substâncias bioativas. Em relação ao potencial antisséptico, H. martiana teve ação pareada com o cloro, contudo aquele agiu mais rapidamente, enquanto o cloro agiu de modo ideal uma hora após a aplicação; ambos os resultados destacam que o extrato etanólico bruto das folhas de H. martiana possui potencial de combate à proliferação de bactérias ambientais e infecciosas, surgindo como uma forma de prevenir a mastite.(AU)


This study aimed to evaluate the antimicrobial and antiseptic action of the crude ethanolic extract of Hymenaea martiana leaves. The study was conducted at the Laboratory of Microbiology and Immunology of UNIVASF, city of Petrolina, state o Pernambuco. The extracts were prepared using different solvents, such as absolute ethyl alcohol and distilled water. Then, Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) techniques were used. All assays were performed in triplicate. The average of MBC extract diluted in ethanol was 358µg/mL, and the extract diluted in distilled water was equal to 520.82µg/mL. There was no difference (P<0.05) and bacterial inhibition to extract diluted in absolute ethanol or autoclaved distilled water. Comparing the activity of the extract diluted in ethanol and the relation with the presence of blaZ gene, it was observed that the negative strains for there searched gene showed a MBC equal to 412.3µg/mL in relation to those that were positive for blaZ gene, that was 308.80µg/µL, and, however, there was no statistical difference. The bacterial inhibition activity using an aqueous extract was equal for the bacteria that had or not the blaZ gene (520.82µg/mL). Thus, the extract diluted in absolute ethanol in autoclaved distilled water as demonstrated antimicrobial activity, suggesting that occurred extraction of bioactive substances. Regarding the antiseptic potential, H. martiana had the same action of chlorine, although, this acted immediately, while the chlorine action happened properly an hour after the application. Both results pointed out that the crude ethanolic extract of H. martiana leaves has potential to combat the proliferation of environmental and infectious bacteria, emerging as a way to prevent mastitis.(AU)


Assuntos
Animais , Staphylococcus/patogenicidade , Cabras/microbiologia , Anti-Infecciosos/análise , Hymenaea/química , Glândulas Mamárias Animais
7.
Genet Mol Res ; 12(3): 2712-24, 2013 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-23979896

RESUMO

Hymenaea courbaril L., popularly known as jatobá, is a plant species that grows in the forests of South America. The species has been used for culinary purposes and in folk medicine to treat arthritis and inflammations. Due to the increasing use of this plant globally, the present study aimed to evaluate the toxic, genotoxic, recombinogenic, and antigenotoxic effects of H. courbaril sap (Hycs) using the mouse bone marrow micronucleus test and the somatic mutation and recombination test (SMART) in Drosophila melanogaster. To evaluate the aneugenic and clastogenic activities revealed by the micronucleus test, the animals were treated with 3 doses of Hycs (5, 10, and 15 mL/kg body weight). To evaluate the antianeugenic and anticlastogenic activities, the animals were simultaneously treated with Hycs and mitomycin C (4 mg/kg body weight). To assess the mutagenic and recombinogenic activities using SMART, 3-day-old larvae derived from standard and high bioactivation crosses were treated with 3 doses of Hycs (3.0, 1.5, and 0.3 mL) for approximately 48 h. To evaluate antimutagenic and antirecombinogenic activities, larvae derived from both crosses were co-treated with 3 doses of Hycs (3.0, 1.5, and 0.3 mL) and doxorubicin (0.125 mg/ mL). The mouse bone marrow micronucleus test revealed that Hycs exhibited no cytotoxic, clastogenic and/or aneugenic effects, but did show anticytotoxic, anticlastogenic and/or antianeugenic activities. The SMART revealed no mutagenic or recombinogenic effects, but antimutagenic and antirecombinogenic activities were observed in somatic cells of D. melanogaster from both crosses.


Assuntos
Dano ao DNA , Hymenaea/química , Mutagênese/efeitos dos fármacos , Extratos Vegetais/toxicidade , Recombinação Genética/efeitos dos fármacos , Animais , Células da Medula Óssea/efeitos dos fármacos , Relação Dose-Resposta a Droga , Drosophila melanogaster , Larva/efeitos dos fármacos , Camundongos , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Extratos Vegetais/farmacologia
8.
J Ethnopharmacol ; 143(1): 81-90, 2012 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-22750452

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Hymenaea stigonocarpa Mart. ex Hayne (Fabaceae) is a medicinal species commonly found in the Brazilian savannah. The stem bark of this medicinal plant, popularly known as "jatobá-do-cerrado", is widely used in tea form to treat gastric pain, ulcers, diarrhoea and inflammation, whereas its fruits pulp is edible. AIM OF THE STUDY: The aim of this study was to investigate the antidiarrheal and anti-ulcer effects of a methanolic extract derived from the stem bark (MHs) and diet with fruit pulp of H. stigonocarpa. MATERIALS AND METHODS: The antidiarrheal action of MHs was measured against the intestinal motility and diarrhoea induced by castor oil in mice. The preventive action of MHs (50, 100, 150 and 200mg/Kg, by oral route (p.o.)) against peptic ulcers was evaluated in experimental rodent models challenged with absolute ethanol, non-steroidal anti-inflammatory drugs (NSAIDs), ischemia-reperfusion (I/R) (200mg/Kg, p.o.) and cysteamine (200mg/Kg, p.o.). The main anti-ulcer mechanisms of action of MHs were analysed as follows: evaluation of the gastric juice parameters, assessment of mucus adherence to the gastric wall, determination of the role of nitric oxide (NO) and sulfhydryl compounds (SH), glutathione (GSH) levels and myeloperoxidase (MPO) activity. The healing effects from MHs (200mg/Kg) and diet with fruit pulp (10%) against gastric and duodenal ulcers induced by acetic acid were also evaluated by treating rats over 7 or 14 consecutive days of treatment. RESULTS: The phytochemical profile of MHs and fruit pulp indicated the presence of phenolic compounds (mainly flavonoids and condensed tannins). MHs (200mg/Kg, p.o.) displayed an antidiarrheal effect and were able to protect gastric mucosa against absolute ethanol (68% protection) and also against the injurious effect of NSAIDs (86% protection) when compared to the group treated with vehicle. These results were accompanied by the prevention of GSH depletion and an inhibition of MPO activity when compared to animals treated with vehicle (P<0.05). MHs markedly protected duodenal mucosa against injuries caused by cysteamine (98%) and also against I/R induced gastric ulceration (80%) when compared to the group treated with vehicle. Furthermore, MHs also prevented the GSH depletion of gastric mucosa relative to the control group treated with vehicle. NO appeared to be involved in this gastroprotective effect. MHs and diet with fruit pulp clearly demonstrated gastric healing actions after treatment for 7 (MHs - 53% inhibition) or 14 days (MHs - 60% inhibition and fruit pulp - 61% inhibition). Treatment with diet with fruit pulp for 7 days demonstrates a significant duodenal healing effect (71% inhibition) without any signs of toxicity. CONCLUSIONS: MHs clearly demonstrate antidiarrheal, gastroprotective and cicatrising effects in experimental gastric and duodenal ulcers, and the diet with fruit pulp displays duodenal healing effects. The observed effects may be associated with the antioxidant effect, which may be due the presence of condensed tannins and flavonoids in the bark and fruit of H. stigonocarpa.


Assuntos
Antiulcerosos/uso terapêutico , Antidiarreicos/uso terapêutico , Diarreia/tratamento farmacológico , Úlcera Duodenal/tratamento farmacológico , Hymenaea/química , Fitoterapia , Úlcera Gástrica/tratamento farmacológico , Animais , Anti-Inflamatórios não Esteroides , Antiulcerosos/farmacologia , Antidiarreicos/farmacologia , Brasil , Óleo de Rícino , Cisteamina , Diarreia/induzido quimicamente , Modelos Animais de Doenças , Úlcera Duodenal/dietoterapia , Etanol , Feminino , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Frutas , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/patologia , Glutationa/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Masculino , Camundongos , Camundongos Endogâmicos , Óxido Nítrico/metabolismo , Peroxidase/metabolismo , Fenóis/farmacologia , Fenóis/uso terapêutico , Casca de Planta , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Caules de Planta , Plantas Medicinais , Ratos , Ratos Wistar , Traumatismo por Reperfusão/tratamento farmacológico , Úlcera Gástrica/dietoterapia , Úlcera Gástrica/metabolismo , Úlcera Gástrica/patologia , Taninos/farmacologia , Taninos/uso terapêutico
9.
Braz. j. biol ; 70(1): 75-83, Feb. 2010. tab, ilus
Artigo em Inglês | LILACS | ID: lil-539735

RESUMO

The present study investigated changes in photosynthetic characteristics of Guazuma ulmifolia Lam. (early successional species) and Hymenaea courbaril L. (late successional species) grown in contrasting light conditions as a way of assessing photosynthetic plasticity. Early successional species typically inhabit gap environments being exposed to variability in multiple resources, hence it is expected that these species would show higher photosynthetic plasticity than late successional ones. In order to test this hypothesis, light and CO2 response curves and chlorophyll content (Chl) were measured in plants grown in high and low light environments. G. ulmifolia presented the highest amounts of both Chl a and b, especially in the low light, and both species presented higher Chl a than b in both light conditions. The Chl a/b ratio was higher in high light leaves of both species and greater in G. ulmifolia. Taken together, these results evidence the acclimation potential of both species, reflecting the capacity to modulate light harvesting complexes according to the light environment. However, G. ulmifolia showed evidence of higher photosynthetic plasticity, as indicated by the greater amplitude of variation on photosynthetic characteristics between environments shown by more significant shade adjusted parameters (SAC) and principal component analysis (PCA). Thus, the results obtained were coherent with the hypothesis that the early successional species G. ulmifolia exhibits higher photosynthetic plasticity than the late successional species H. courbaril.


O presente estudo investigou mudanças nas características fotossintéticas de Guazuma ulmifolia Lam. (pioneira) e Hymenaea courbaril L. (secundária) crescidas sob condições luminosas contrastantes, como uma maneira de acessar a plasticidade fotossintética das espécies. Espécies pioneiras geralmente habitam ambientes de clareira, expostas a uma ampla variação em múltiplos recursos, o que indica que essas espécies podem apresentar maior plasticidade fotossintética do que espécies secundárias. A fim de testar essa hipótese, foram feitas curvas de resposta à luz e ao CO2 e medidas do conteúdo de clorofila (Chl) em plantas crescidas em ambientes com alta e baixa luminosidade. G. ulmifolia apresentou os maiores teores de Chl a e b, principalmente em baixa luminosidade, e ambas as espécies apresentaram maior conteúdo de clorofila a do que b em ambas as condições luminosas. A razão Chl a/b foi maior em folhas de sol em ambas as espécies e foi mais elevada em G. ulmifolia. Conjuntamente, esses resultados evidenciam um potencial de aclimatação em ambas as espécies, indicando a capacidade de modular os complexos antena de acordo com o ambiente luminoso. Contudo, G. ulmifolia mostrou evidências de maior plasticidade fotossintética, conforme indicado pela maior amplitude de variação nas características fotossintéticas entre ambientes, maior número de parâmetros significativamente justados à sombra (SAC) e pela análise de componentes principais (PCA). Assim, os resultados obtidos foram coerentes com a hipótese de que a espécie pioneira G. ulmifolia apresenta maior plasticidade fotossintética do que a secundária H. courbaril.


Assuntos
Adaptação Fisiológica/fisiologia , Hymenaea/fisiologia , Malvaceae/fisiologia , Fotossíntese/fisiologia , Luz Solar , Dióxido de Carbono/análise , Clorofila/análise , Hymenaea/química , Malvaceae/química
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