Navegando por Assunto "Leguminosa"

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Acesso aberto (Open Access)
Atividade alelopática de substâncias químicas isoladas da Acacia mangium e suas variações em função do PH
(2010) LUZ, Sylmara de Melo; SOUZA FILHO, Antonio Pedro da Silva; GUILHON, Giselle Maria Skelding Pinheiro; VILHENA, Karyme do Socorro de Souza
The aim of this study was to isolate, identify and characterize the allelopathic activity of the substances produced by Acacia mangium and to determine the variations of this activity according to the pH variation of the solution. The allelopathic activity was evaluated in germination bioassays (at 25 oC and under 12-12 h light-dark cycle) and radicle and hypocotyl development (at 25 oC and under 24-24 h light-dark cycle) of the weed species malicia (Mimosa pudica) and mata-pasto (Senna obtusifolia). The influence of the pH (3.0 and 9.0) of the solution in the allelopathic activity of the substances on seed germination of the same species was evaluated. The triterpenoids Lupenone (3 oxolup-20(29)-ene) and Lupeol (3β-hydroxylup-20(29)-ene), obtained from fallen leaves of the donor plant, separately and in pair, showed low allelopathic effects on seed germination and hypocotyl growth, especially on the former, with effects showing values lower than 2%. The effects on radicle growth were higher than the other two, reaching values above 40%, especially inhibition promoted by the substance Lupenone. Separately, each substance showed higher effects than those observed when tested in pair, indicating the existence of antagonism. The pH of the solution influenced the allelopathic activity of the substances; for Lupenone, the effects were more intense at acidic pH, while for Lupeol, best results were observed under alkaline conditions, showing that this is an important factor to be considered in field works.
Acesso aberto (Open Access)
Dihydroflavonols from the leaves of Derris urucu (Leguminosae): structural elucidation and DPPH radical-scavenging activity
(2009) LÔBO, Lívia Trindade; SILVA, Geilson Alcantara da; FERREIRA, Malisson; SILVA, Milton Nascimento da; SANTOS, Alberdan Silva; ARRUDA, Alberto Cardoso; GUILHON, Giselle Maria Skelding Pinheiro; SANTOS, Lourivaldo da Silva; BORGES, Rosivaldo dos Santos; ARRUDA, Mara Silvia Pinheiro
Derris urucu is an Amazonian plant with insecticide and ichthyotoxic properties. Studies with this species show the presence of flavonoids, mainly rotenoids, as well as stilbenes. The ethanol extract of the leaves of Derris urucu (Leguminosae) afforded three new dihydroflavonols named urucuol A (1), B (2) and C (3), and the dihydroflavonol isotirumalin (4). Their structures were elucidated by extensive analysis of 1D and 2D NMR, UV and IR spectra and MS data and comparison with literature data. The isolated compounds (1-4) were evaluated for DPPH• radical scavenging activity and showed a relatively lower antioxidant ability compared to the commercial antioxidant trans-resveratrol.
Acesso aberto (Open Access)
Flavonoids from the leaves of Deguelia utilis (Leguminosae): structural elucidation and neuroprotective properties
(2012-10) OLIVEIRA, Dalglish Gomes de; ALMEIDA, Cecília M. C. de; SILVA, Consuelo Yumiko Yoshioka e; ARRUDA, Mara Silvia Pinheiro; ARRUDA, Alberto Cardoso; LOPES, Dielly Catrina Favacho; YAMADA, Elizabeth Sumi; COSTA, Edmar Tavares da; MARTINS FILHO, Arnaldo Jorge; SILVA, Milton Nascimento da
Five new flavonoids, 5,3'-dihydroxy-4'-methoxy-2'',2''-dimethylchromene-(5'',6'':6,7)dihydroflavonol (1), 5,3'-dihydroxy-7,4'-dimethoxy-6,8-dimethylallyl-dihydroflavonol (2), 5,3'-dihydroxy-4'-methoxy-8-allyl-2'',2''-dimethylchromene-(5'',6'':6,7) flavanone (3), 5,3'-dihydroxy-7,4'-dimethoxy-6,8-dimethylallyl-flavanone (4), 3,5,3'-trihydroxy-7,4'-dimethoxy6,8-dimethylallyl-flavanol (5), together with the stilbenes 4-methoxylonchocarpene (6) and lonchocarpene (7) were isolated from the leaves of Deguelia utilis. Their chemical structures were established on the basis of NMR (nuclear magnetic resonance) spectral data and HRESITOF-MS (electrospray ionization-high resolution time-of-flight mass spectrometry). Also, in order to investigate potential cytoprotective effects of these flavonoids, we used a fraction eluted with hexane:EtOAc containing all seven flavonoids, in an in vitro model of neurodegeneration, using hippocampal primary cultures from neonatal (PND2-P3) rats exposed to rotenone, a mitochondrial complex I inhibitor. There was a significant reduction in cell viability (19.4 ± 1.6%) when the cultures were exposed to 30 nmol L-1 rotenone for 72 h. Concomitant exposure of the cultures to the FR3 (5 µg mL-1) and 30 nmol L-1 rotenone resulted in values of cell viability similar to control groups (99.6 ± 4.8%), strongly suggesting a cytoprotective effect for this flavonoid-rich fraction.
Acesso aberto (Open Access)
Organic material decomposition and nutrient dynamics in a mulch system enriched with leguminous trees in the Amazon
(2008-06) CATTANIO, José Henrique; KUEHNE, Ronald; VLEK, Paul L.G.
The new techniques proposed for agriculture in the Amazon region include rotational fallow systems enriched with leguminous trees and the replacement of biomass burning by mulching. Decomposition and nutrient release from mulch were studied using fine-mesh litterbags with five different leguminous species and the natural fallow vegetation as control. Samples from each treatment were analyzed for total C, N, P, K, Ca, Mg, lignin, cellulose content and soluble polyphenol at different sampling times over the course of one year. The decomposition rate constant varied with species and time. Weight loss from the decomposed litter bag material after 96 days was 30.1 % for Acacia angustissima, 32.7 % for Sclerolobium paniculatum, 33.9 % for Iinga edulis and the Fallow vegetation, 45.2 % for Acacia mangium and 63.6 % for Clitoria racemosa. Immobilization of N and P was observed in all studied treatments. Nitrogen mineralization was negatively correlated with phenol, C-to-N ratio, lignin + phenol/N ratio, and phenol/phosphorus ratios and with N content in the litterbag material. After 362 days of field incubation, an average (of all treatments), 3.3 % K, 32.2 % Ca and 22.4 % Mg remained in the mulch. Results confirm that low quality and high amount of organic C as mulch application are limiting for the quantity of energy available for microorganisms and increase the nutrient immobilization for biomass decomposition, which results in competition for nutrients with the crop plants.
Acesso aberto (Open Access)
Valor nutritivo da leguminosa Flemingia macrophylla (Willd.) Merrill para suplementação alimentar de ruminantes na Amazônia Oriental
(Universidade Federal do Pará, 2007) AVIZ, Márcia Alessandra Brito de; CAMARÃO, Ari Pinheiro; http://lattes.cnpq.br/1649891765946593; LOURENÇO JÚNIOR, José de Brito; http://lattes.cnpq.br/2919433679918544
The knowledge of the nutritional value of forage plants is of great relevance when it is intended to raise the productivity of the cattle systems in the Eastern Amazon, mainly in areas where deficiency of fodder plant of good quality occurs, in periods of water deficit. Thus, to characterize the potentiality of the leguminous Flemingia macrophylla (Willd.) Merril, as alternative for animal feeding, assumes excellent importance, therefore it can influence in the productive performance for meat and dairy cattle. This research aimed to evaluate the chemical composition, apparent digestibility and voluntary intake of this leguminous in the suplementary feeding of ruminants, in period of reduced availability of fodder plant and low nutritional value. The work was realized at the Embrapa Eastern Amazon, in Belem, Para State, Brazil (1º28'S 48º27'W). The nutrition characteristics of the leguminous were determined, during 21 days, with 16 sheeps, in individual metabolic cage, distributed in completely randomized, with four treatments and four repetitions. The experimental treatments (T1, T2, T3 and T4) contained Brachiaria humidicola and creasing levels of 100%, 75%, 50% and 25% of inclusion of F. macrophylla. The tannin level in the composition of the diet was 1.37; 0.62; 0.31 and 0.17%, respectively. The consumption of dry matter (g/day) and % of live weight were 901.8 and 2.4; 947.9 and 2.5; 859.5 and 2.2; e 930.2 and 2.5 and of crude protein 232.4; 188.7; 132.1 and 107.6 g/day. The coefficients of digestibilidade were 54.1; 59.2; 55.1; e 62.0%, in dry matter, and 57.3; 61.2; 57.6; e 64.0% in organic matter and the crude protein were 63.2; 60.5; 51.4; 52.0%, respectively. The leguminous has feeding potential, with high availability of dry matter, to be used as alternative for ruminants feeding supplementation, mainly in critical periods. Level of inclusion of F. macrophylla, around 75%, make possible greater consumption of the dry matter, organic matter and of fiber fractions and 100% allow better consumption of crude protein and gross energy.
Acesso aberto (Open Access)
Valor nutritivo da leguminosa Pueraria phaseoloides (Roxb.) Benth como alternativa na suplementação alimentar de ruminantes na Amazônia Oriental
(Universidade Federal do Pará, 2007-12-07) MONTEIRO, Edwana Mara Moreira; LOURENÇO JÚNIOR, José de Brito; http://lattes.cnpq.br/2919433679918544
This work was realized in the Animal Research Unit "Senator Alvaro Adolpho" in the Embrapa Eastern Amazon, in Belem, Para State, to evaluate the effect of four levels of substitution (25%, 50%, 75% and 100%) of the Pueraria phaseoloides (Roxb.) Benth leguminous, in the voluntary consumption and apparent digestibility of the dry substance (MS), crude protein (PB), crude energy (EB), detergent neutral fiber (FDN) and acid detergent fiber (FDA). The experiment was of 14 days of adaptation and seven days of experimental period, using sixteen sheep’s, of ten months and 28 (± 2,44) average of kg, in a completely randomized experimental design, with four treatments and four repetitions. The data had been analyzed by software SAS. The substitution of the quicuio-da-Amazônia for the pueraria in the diet influenced the voluntary consumption and the apparent digestibility of all the nutrients, being described for quadratic function. A quadratic increase in the apparent consumptions of the FDN was evidenced and FDA, however, with increase of the level of leguminous in the diet, had been observed significant reductions in the FDN text when the 75% level was supplied. The use of the Pueraria phaseoloides leguminous, provides to greater availability of dry substance in the fodder plant and rise of the nutritional value, mainly, protein in the diet, promoting increase of the animal productivity. Levels of substitution of P. Phaseoloides, around 100%, make possible greater consumption of the dry substance, organic substance, PB and EB, while that, the 75% level allows to greater consumption of the fibroses fractions.
Acesso aberto (Open Access)
Valor nutritivo de Cratylia argentea para suplementação de ruminantes na Amazônia
(Universidade Federal do Pará, 2007) SANTOS, Núbia de Fátima Alves dos; CAMARÃO, Ari Pinheiro; http://lattes.cnpq.br/1649891765946593; LOURENÇO JÚNIOR, José de Brito; http://lattes.cnpq.br/2919433679918544
The study was carried out at the Embrapa Eastern Amazon, in Belem, Para State, Brazil (1º28'S 48º27'W of Greenwich), with the objective of evaluate the influence of the addition of the Cratylia argentea as alternative feed supplementation of ruminants, in the critical periods of forage production of in the Eastern Amazon. The nutritional characteristics of the leguminous was determined during twenty one days, using sixteen sheep, in individual metabolic cage, distributed in a completely randomized experimental design, with four treatments and four replications. The experimental rations (T1, T2, T3 and T4) contained Brachiaria humidicola and crescent levels of 25%, 50%, 75% and 100%, of inclusion of Cratylia argentea. The consumption of dry matter (g/day) and live weight percent were 656.47 and 1.76; 743.50 and 1.96; 714.92 and 1.89; and 480.52 and 1.31, of organic matter 619.64; 715.85; 665.36 and 535.85 g/day, and of crude protein 68.01; 108.29; 187.67 and 170.61 g/day. The fiber in neutral detergent consumption in g/day, were 567.44; 536.70; 486.51 and 382.25 g/day. The coefficients of digestibility were 37.87; 24.01; 21.93 and 34.36%, in dry matter basis, and 42.66; 31.54; 27.02 and 36.05%, in organic matter basis, and the crude protein contents were 56.04; 56.64; 68.66 and 71.44%, in 25%, 50%, 75% e 100% on inclusion of Cratylia argentea, respectively. The Cratylia argentea constitute alimentary alternative during the low rainy, with medium digestibility of dry matter, organic matter, crude protein and fibrous fractions, same in blooming, thus presented medium consumption due the tannins. At the level of 50%, possibility greater consumption of dry matter, organic matter, crude protein, grow energy and fibrous fractions.