Valor nutritivo da leguminosa Flemingia macrophylla (Willd.) Merrill para suplementação alimentar de ruminantes na Amazônia Oriental

O conhecimento do valor nutritivo de plantas forrageiras é de grande relevância quando se pretende elevar a produtividade dos sistemas pecuários na Amazônia Oriental, principalmente em áreas onde ocorre deficiência de forragem de boa qualidade, em períodos de déficit hídrico. Assim, caracterizar a potencialidade da leguminosa Flemingia macrophylla (Willd.) Merrill, como alternativa para alimentação animal, assume relevante importância, pois pode influenciar no desempenho produtivo de bovídeos para carne e leite. Dessa forma, esta pesquisa visou avaliar a composição química, digestibilidade aparente e consumo voluntário dessa leguminosa na alimentação suplementar de ruminantes, em períodos de reduzida disponibilidade de forragem, de baixo valor nutritivo. O trabalho foi realizado na Embrapa Amazônia Oriental, em Belém-Pará, (1º28´ S 48º27´ W de Greenwich). Foram determinadas as características nutricionais da leguminosa, durante um período de 21 dias, com 16 ovinos, em gaiolas metabólicas individuais, distribuídas em delineamento inteiramente casualizado, em quatro tratamentos e quatro repetições, onde os tratamentos (T1, T2, T3 e T4) continham quicuio-da-amazônia (Brachiaria humidicola) e níveis crescentes de 100%, 75%, 50% e 25% de inclusão de F. macrophylla. Os teores de tanino na composição da dieta foram 1,37; 0,62; 0,31 e 0,17%, respectivamente. Os consumos de matéria seca, em g/dia e % do peso vivo, foram de 901,8 e 2,4; 947,9 e 2,5; 859,5 e 2,2; e 930,2 e 2,5 e de proteína bruta 232,4; 188,7; 132,1 e 107,6 g/dia. Os coeficientes de digestibilidade da matéria seca foram de 54,1; 59,2; 55,1; e 62,0%, da matéria orgânica de 57,3; 61,2; 57,6; e 64,0% e de proteína bruta de 63,2; 60,5; 51,4; 52,0%, respectivamente. A leguminosa possui potencial produtivo, com elevada disponibilidade de matéria seca, para ser utilizada como suplemento alimentar para ruminantes, principalmente em períodos críticos. Níveis de inclusão de F. macrophylla, em torno de 75%, possibilitam maior consumo da matéria seca, matéria orgânica, e das frações fibrosas e 100% permitem melhor consumo de PB e EB.

In vitro degradability of mature and immature leaves of tropical forage legumes differing in condensed tannin and non-starch polysaccharide content and composition

A study was designed to examine the relationships between protein, condensed tannin and cell wall carbohydrate content and composition and the nutritional quality of seven tropical legumes (Desmodium ovalifolium, Flemingia macrophylla, Leucaena leucocephala, L pallida, L macrophylla, Calliandra calothyrsus and Clitotia fairchildiana). Among the legume species studied, D ovalifolium showed the lowest concentration of nitrogen, while L leucocephala showed the highest. Fibre (NDF) content was lowest in C calothyrsus, L Leucocephala and L pallida and highest in L macrophylla, which had no measurable condensed tannins. The highest tannin concentration was found in C calothyrsus. Total non-structural polysaccharides (NSP) varied among legumes species (lowest in C calothyrsus and highest in D ovalifolium), and glucose and uronic acids were the most abundant carbohydrate constituents in all legumes. Total NSP losses were lowest in F macrophylla and highest in L leucocephala and L pallida. Gas accumulation and acetate and propionate levels were 50% less with F macrophylla and D ovalifolium as compared with L leucocephala. The highest levels of branched-chain fatty acids were observed with non-tanniniferous legumes, and negative concentrations were observed with some of the legumes with high tannin content (D ovalifolium and F macrophylla). Linear regression analysis showed that the presence of condensed tannins was more related to a reduction of the initial rate of gas production (0-48 h) than to the final amount of gas produced or the extent (144h) of dry matter degradation, which could be due to differences in tannin chemistry. Consequently, more attention should be given in the future to elucidating the impact of tannin structure on the nutritional quality of tropical forage legumes. (C) 2003 Society of Chemical Industry.

Effect of condensed tannins from tropical legumes on the activity of fibrolytic enzymes from the rumen fungus Neocallimastyx hurleyensis

A study was conducted to assess the effect of condensed tannins on the activity of fibrolytic enzymes from the anaerobic rumen fungus, Neocallimastix hurleyensis and a recombinant ferulic acid esterase (FAE) from the aerobic fungus Aspergillus niger. Condensed tannins were extracted from the tropical legumes Desmodium ovalifolium, Flemingia macrophylla, Leucaena leticocephala, Leucaena pallida, Calliandra calothyrsus and Clitoria fairchildiana and incubated in fungal enzyme mixtures or with the recombinant FAE. In most cases, the greatest reductions in enzyme activities were observed with tannins purified from D. ovalifolium and F macrophylla and the least with tannins from L leucocephala. Thus, whereas 40 mu g ml(-1) of condensed tannins from C. calothyrsus and L. leucocephala were needed to halve the activity of N. hurleyensis carboxymethylcellulase (CMCase), just 5.5 mu g ml(-1) of the same tannins were required to inhibit 50% of xylanase activity. The beta-D-glucosidase and beta-D-Xylosidase enzymes were less sensitive to tannin inhibition and concentrations greater than 100 mu g ml(-1) were required to reduce their activity by 50%. In other assays, the inhibitory effect of condensed tannins when added to incubation mixtures containing particulate substrates (the primary cell walls of E arundinacea) or when bound to these substrate was compared. Substrate-associated tannins were more effective in preventing fibrolytic activities than tannins added directly to incubations solutions. It was concluded that condensed tannins from tropical legumes can inhibit fibrolytic enzyme activities, although the extent of the effect was dependent on the tannin, the nature of its association with the substrate and the enzyme involved. (c) 2005 Elsevier Inc. All rights reserved.

Pyrolysis decomposition of mahogony seeds (Swietenia macrophylla) for alternative fuel oil

A fixed bed pyrolysis has been designed and fabricated for obtaining liquid fuel from Mahogany seeds. The major components of the system are fixed bed pyrolysis reactor, liquid condenser and liquid collectors. The Mahogany seed in particle form is pyrolysed in an externally heated 10 cm diameter and 36 cm high fixed bed reactor with nitrogen as the carrier gas. The reactor is heated by means of a biomass source cylindrical heater from 450oC to 600oC. The products are oil, char and gas. The reactor bed temperature, running time and feed particle size are considered as process parameters. A maximum liquid yield of 54wt% of biomass feed is obtained with particle size of 1.18 mm at a reactor bed temperature of 5500C with a running time of 90 minutes. The oil is found to possess favorable flash point and reasonable density and viscosity. The higher calorific value is found to be 39.9 MJ/kg which is higher than other biomass derived pyrolysis oils.

Responses of Swietenia macrophylla (King) seedlings to different sizes of canopy openings in mixed mahogany plantations

A study was conducted during 1997-99 at 2 sites in Sri Lanka (Rambukkana and Kurunegala) to investigate the responses of Swietenia macrophylla seedlings to wide, moderate and narrow openings of high to low shade conditions in a mature mixed mahogany plantations. Survival, stem growth and shoot phenology of seedlings were recorded monthly. Seedling survival a year after planting showed high mortality under high shaded gap (3-8% photosynthetically active radiation (PAR)). At 51 weeks after planting, final stem height and root collar diameter were highly significant under low shaded gaps. Increased number of shoots and shoot lenghts were observed under low shade (50-78% PAR). Increased flushing was seen in all shade regimes during the rainy period. This study illustrates that low shaded gap openings favour seeding survival, stem and shoot growth, and number of shoots. On the contrary, high shaded gaps reduce the growth of seedlings and therefore may be less attractive to shoot borers.

Xylarenones C-E from an Endophytic Fungus Isolated from Alibertia macrophylla

Xylarenones C-E (2-4), three new eremophilane sesquiterpenes, have been isolated from solid substrate cultures of a Camarops-like endophytic fungus isolated from Alibertia macrophylla. The structures were elucidated by analysis of spectroscopic data. Compounds were evaluated in subtilisin and pepsin protease assays, and compound 2 showed potent inhibitory activity against both proteases.

Imbibition of Swietenia macrophylla (Meliaceae) seeds: the role of stomata

Background and Aims the occurrence of stomata in seed coats is uncommon and there is limited information about their function(s). The aim of this study was to verify the distribution of stomata in seed coats of Swietenia macrophylla and to relate it to the imbibition process and aspects of the structure of the outer integument layers.Methods For the structural and ultrastructural studies, the seeds were processed using the usual techniques and studied under light and scanning electron microscopes. Histochemical tests were employed to identify the cell wall composition in the different seed coat portions. To assess the role of the stomata in the imbibition, non-impervious seeds were compared with partially impervious ones, in which only the embryo, median or hilar regions were left free. Further, the apoplastic pathway marker was employed to confirm the role of the stomata as sites of water passage during imbibition.Key Results A positive relationship was observed between seed coat thickness and stomata density. The stomata were devoid of movement, with a large pore. They occurred in large numbers in the embryo region and extended with lower frequency towards the wing. Imbibition rates were related to stomata density, suggesting that the stomata act as preferential sites for water entry in the S. macrophylla seeds.Conclusions At maturity, the stomata in the seed coat play a significant role in seed imbibition. The data may also infer that these permanently opened stomata have an important role in gas exchange during seed development, aiding embryo respiration.

Dihydroisocoumarins produced by Xylaria sp and Penicillium sp., endophytic fungi associated with Piper aduncum and Alibertia macrophylla

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Xylarenones C-E from an Endophytic Fungus Isolated from Alibertia macrophylla

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Bioactive Metabolites Produced by Penicillium sp.1 and sp.2, Two Endophytes Associated with Alibertia macrophylla (Rubiaceae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Influência de diferentes tipos de estacas e substratos na propagação assexuada de hortênsia [Hydrangea macrophylla (Thunb.) Ser.]

A hortênsia (Hydrangea macrophylla) é um arbusto semilenhoso de 1,0 a 2,5 m de altura, de folhagem e florescimento decorativos, muito utilizados como flor de vaso e planta para paisagismo. Conduziu-se este trabalho com o objetivo de estudar o enraizamento de estacas de três partes da planta: apical, mediana e basal; em três tipos de substratos: terra, areia e vermiculita, para a formação de mudas. As estacas foram retiradas das plantas matrizes e divididas em segmentos apical, mediano e basal, os quais foram colocados para enraizar em bandejas de isopor, nos substratos areia, terra e vermiculita, em estufa com nebulização. As estacas que apresentaram melhor qualidade de raízes foram as originadas da parte basal do ramo, sendo que o melhor enraizamento foi observado nas estacas colocadas em areia. As estacas obtidas de diferentes partes da planta não se diferenciaram quanto à porcentagem de enraizamento e quanto ao número de brotos formados. Já os substratos que proporcionaram o maior número de brotações foram a areia e a terra. Algumas estacas apresentaram formação de flores, ocorrendo com maior freqüência nas estacas apicais, sem efeito dos substratos. A areia foi o substrato que proporcionou os melhores resultados quanto à qualidade das raízes e porcentagem de enraizamento. O substrato terra foi superior apenas para o número de brotos por estaca, porém não diferenciou estatisticamente da areia. Mudas formadas de estaca da parte basal da planta se mostraram com qualidade superior.

EXTRAFLORAL NECTARIES IN THE TROPICAL TREE GUAREA-MACROPHYLLA (MELIACEAE)

This paper describes the anatomy and morphology of the complex nectary systems of the tropical tree Guarea macrophylla Vahl (Meliaceae) and presents the first record of extrafloral nectaries occurring on reproductive organs (fruits) of a member of the order Sapindales. The extrafloral nectaries of G. macrophylla occur on petioles, petiolules, the abaxial surface of all leaflets, leaf buds, and over the surface of fruits. All extrafloral nectaries are distinctly raised above the surface. Foraging ants collect extrafloral nectar on Guarea trees both day and night. We suggest that the presence of extrafloral nectaries might be a useful taxonomic character for the identification of Guarea species.

A new ent-kaurane diterpene from stems of Alibertia macrophylla K. Schum. (Rubiaceae)

Phytochemical investigations of the stems of a specimen of Alibertia macrophylla led to the isolation and characterization of the new diterpene ent-kaurane-2β,3α,16α-triol (1), along with triterpenes 2-8, iridoids 9-12, and phenolic acids 13-15. The structure of 1 was established based on spectroscopic studies (1H- and 13C-NMR, IR, and HR-ESI-MS). This is the first report of the isolation of a diterpene from the Alibertia genus in Rubiaceae. © 2007 Verlag Helvetica Chimica Acta AG.