oalib
Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
Polyprenol from the Whole Plants of Leucaena leucocephala  [PDF]
Chung-Yi Chen, Yau-Der Wang
Journal of Environmental Protection (JEP) , 2010, DOI: 10.4236/jep.2010.11009
Abstract: Ficaprenol-11 (polyprenol) (1), squalene (2), lupeol (3), ?-sitostenone (4), trans-coumaric acid (5), cis-coumaric acid (6) pheophytin-a (7), pheophorbide a methyl ester (8), methyl-132-hydroxy-(132-S)- pheophorbide-b (9) and aristo-phyll-C (10) were isolated from the whole plants of Leucaena leucocephala (Leguminosae). Among them, 1 and 2 was found for the first time from this species. The structure of these compounds were characterized and identified by spectra analyses.
STUDIES ON SOME PHYSICOCHEMICAL PROPERTIES OF LEUCAENA LEUCOCEPHALA BARK GUM
Vijetha Pendyala,Chandu Baburao,K.B Chandrasekhar
Journal of Advanced Pharmaceutical Technology & Research , 2010,
Abstract: Gum exudates from Leucaena Leucocephala (Family: Fabaceae) plants grown all over India were investigated for its physicochemical properties such as pH, swelling capacity and viscosities at different temperatures using standard methods. Leucaena Leucocephala bark gum appeared to be colorless to reddish brown translucent tears. 5 % w/v mucilage has pH of 7.5 at 28°C. The gum is slightly soluble in water and practically insoluble in ethanol, acetone and chloroform. It swells to about 5 times its original weight in water. A 5 %w/v mucilage concentration gave a viscosity value which was unaffected at temperature ranges (28-40°C). At concentrations of 2 and 5 %w/v, the gum exhibited pseudo plastic flow pattern while at 10 %w/v concentration the flow behaviour was thixotropic. The results indicate that the swelling ability of Leucaena Leucocephala (LL) bark gum may provide potentials for its use as a disintegrant in tablet formulation, as a hydro gel in modified release dosage forms and the rheological flow properties may also provide potentials for its use as suspending and emulsifying agents owing to its pseudo plastic and thixotropic flow patterns.
Nutri？？o mineral de leguminosas tropicais: III. concentra？？o e acúmulo de macronutrientes e determina？？o do coeficiente de digestibilidade in vivo da Leucaena leucocephala (LAM.) de Wit cv. Peru em fun？？o da idade
Silva, Denise Helu;Haag, Henrique Paulo;
Anais da Escola Superior de Agricultura Luiz de Queiroz , 1982, DOI: 10.1590/S0071-12761982000100029
Abstract: the tropical leguminous olants are known as a high quality protein source and in some cases even as wood producers when dealing with the arbustive types. the leucena (leucaena leucocephala (lam.) de wit cv. peru) was noticed as a very promising species to the brazilian cattle production, and this fact leads to the setting of a field experiment in order to know its nutrient demands. the experiment was carried out to obtain data for analysis of growth, concentration and extraction of macronutrients (n, p, k, ca, mg, s and the dry matter digestibility in vivo for the leaves relatad to the plant age. from the obtained data it was possible to verify that: the whole dry matter production is the highest when the plant was 360 days old. the largest increase in the leaf production in dry matter was observed from 240 days up to 360 days. the n and p concentrations decreased in leaves and stem along the plant life. an the other hand, the age of the plant did not affect the ca concentration in the stem leaves not the ca concentration in the stem. when the plants were 360 days old corresponding to the highest dry matter product ion period, the following contents in the leaves and stem were observed: plants with 360 days also showed the macronutrients accumulations in the folowing order: n > k > ca > mg > > s > p. the digestibility of the dry matter in leaves is in the level of 51.05%, in 360 day old plants.
Standardization of extract of Leucaena leucocephala (lmk) De Wit seeds by α-glucosidase inhibitor  [cached]
Syamsudin A
International Journal of Phytomedicine , 2011,
Abstract: Extracts of Leucaena leucocephala (lmk) De Wit seeds were collected from different areas in Java; they include Jakarta, Cengkareng, Bogor and Bandung. Each extract was examined for water content, ash content, acid-insoluble ash content, and α- glycosidase inhibition assay. The results showed that ethanolic extracts of Leucaena leucocephala (lmk) De Wit seeds collected from Bandung were found to be most active in inhibiting the formation of α-glycosidase compounds with an IC50 value of 7,46 ± 0,21 μg/ml, which was confirmed with ash content of 5,58 ± 0,04, acid-insoluble ash content of 0,55 ± 1,33, and water content of 26,22 ± 0,90. Keywords: extracts of (Leucaena leucocephala (lmk) De Wit), α-glucosidase inhibition activity, different areas in Java.
Natural regeneration of Leucaena leucocephala in Yuanmou dry-hot valley
元谋干热河谷地区新银合欢天然更新的初步调查
ZONG Yi-chen,ZHENG Yong-qi,ZHANG Chuan-hong,DUAN Fu-wen,WANG Zhi-he,
宗亦臣,郑勇奇,张川红,段福文,王志和
生态学杂志 , 2007,
Abstract: In this paper, an investigation was made on the Leucaena leucocephala plantations in Yuanmou dry-hot valley in June and October 2005. Under the plantations, there were a great many of seedlings, and all of them were generated from seeds, suggesting that L. leucocephala could naturally regenerate from seed. The seed quantity per tree was from 602 to 1 513, and high trees had more seeds. The seedlings were growing well, with a minimum renewal density of 960 plants per square meter and a maximum renewal density of 960 plants per square meter. The longest dispersal distance of the seedlings was 58.3 m from the edge of L. leucocephala stand, and the dispersal range was mostly in an area 10 m from the stand. The seeds could be dispersed to a far distance along the valley by wind and running water.
Chemical Composition and Amino Acids Profile of Leucaena leucocephala Seeds  [PDF]
Mohamed Elamin Ahmed,Khadiga Abbas Abdelati
International Journal of Poultry Science , 2009,
Abstract: The utilization of grain legumes such as Leucaena leucocephala by the feed industry is limited because of uncertainty about their nutritional quality. Although the analyzed total amino acid and energy contents of many grain legumes are quite similar, their protein qualities and metabolizable energy values are quite variable. Leucaena leucocephala seeds were analyzed for chemical composition and amino acids profile. The analyzed nutrient composition indicated that leucaena seeds are potential source of protein and energy. The protein content was 31.1% and the calculated metabolizable energy of the seeds was 2573.26 kcal/kg. Amino acids profile of leucaena seeds were 1.39% lysine%, 0.36% methionine, 0.35% cystine, 2.62% arginine, 4.63% glutamic acid, 0.87% threonine, 1.38% glycine, 1.11% alanine, 1.11% valine, 0.93% isoleucine, 1.81% leucine and 0.71% methionine + cystine. Antinutritional Factors (ANFs) were 0.75% tannin and 697.50 mg/100g phytate. Leucaena seed was incorporated at 0, 3, 6, 9 and 12% in broiler chicks' diets. One hundred twenty one-day old unsexed broilers (Ross 308) were used. The performance revealed that, the overall feed intake and body weight gain were significantly (p<0.01) depressed with the inclusion of 6, 9 and 12% leucaena seeds in the diet.
Producción de biomasa y utilización de Leucaena leucocephala fertilizada y pastoreada por ovinos
Camacaro,Selina; Machado,Wilfre;
Zootecnia Tropical , 2005,
Abstract: a field experiment was carried out in the sheep section of the faculty of agronomy of the central university of venezuela, located in maracay, aragua state to evaluate the effect of the fertilization of leucaena leucocephala on the biomass production and its utilization for grazing sheep. an association of the legume already sown in single rows of 1x4 m, on a pasture of cynodon plectostachyous, was used. an aleatory block design was used with three repetitions, including a negative control (without fertilization) and a positive control (s, cu, and zn) and the six remaining treatments with a missing element. four destructive and non destructive samplings were made; the first was made on 10 plants, evaluating height, number of branches, length of branches ？ < 6 mm, length of branches ？ > 6 mm, number of leaves, length of leaves, dry matter of leaves, dry matter of branches ？ < 6 mm and dry matter of branches ？ > 6 mm. for the non destructive samplings, except for dry matter, the same variables were evaluated. there were differences (p<0.05) in the variables msh and mst< for treatment effect, standing out the effect of the s (alone or combined) and the combination of cu and zn, with the other elements, because it produced an increase of available biomass. the mst> and the % of participation of the mst < in the available biomass were not affected by the treatments (p>0.05). the utilization of the l. leucocephala was not affected (p>0.05) by the treatments. the results indicated that under these conditions, the fertilization of l. leucocephala increased the biomass production, but it did not affect its utilization by grazing sheep.
Effect of lead and cadmium on germination and seedling growth of Leucaena leucocephala
M Shafiq, MZ Iqbal, A Mohammad
Journal of Applied Sciences and Environmental Management , 2008,
Abstract: A study was conducted to determine the effect of different concentrations of lead and cadmium on seed germination and seedling growth of Leucaena leucocephala. Seed were grown under laboratory conditions at 25, 50, 75 and 100 ppm of metal ions of lead and cadmium. Both lead and cadmium treatments showed toxic effects on various growth indices of L. leucocephala. Increasing the concentration of lead to 75 ppm, significantly (p<0.05) decreased seed germination as compared to control. Seedling and root growth was significantly (p<0.05) reduced at 50 ppm treatment of lead. Seed germination and root length significantly (p<0.05) decreased at 50 ppm treatment of cadmium as compared to control. The seedling dry weight also significantly (p<0.05) reduced at 25 ppm treatment of lead and cadmium. Cadmium treatment at 100 ppm showed comparatively pronounced effects in L. leucocephala seedlings as compared to lead. The results of the study suggest that due to better metal tolerance indices there is a possibility of growing L. leucocephala in areas contaminated with lead and cadmium.
Effect of Pruning Height on Shoot Biomass Yield of Leucaena leucocephala  [PDF]
S.U. Tipu,K.L. Hossain,M.O. Islam,M.A. Hossain
Asian Journal of Plant Sciences , 2006,
Abstract: An investigation on the effect of pruning height on shoot biomass yield of Leucaena leucocephala was carried out at the Agroforestry Farm, Bangladesh Agricultural University, during February to May 2005. The experiment was laid out in randomized complete block design with three replications. Treatments included four pruning heights; 3-5 (basal cut), 50, 100 and 150 cm above the collar zone. Yield of shoot biomass increased greatly with the increase in pruning heights. Higher pruning heights had a significantly higher number of branches, length of branches and leaves per plant than those of the lower heights. The 150 cm pruning height was found to yield the highest biomass followed by the 100 cm height. The 50 cm and the basal cut were statistically similar with regard to leaf biomass. Therefore, it was concluded that a higher pruning height should be practiced in Leucaena for higher shoot biomass yield.
Efecto modulador de Leucaena leucocephala sobre la microbiota ruminal
Galindo,Juana; González,Niurca; Delgado,Denia; Sosa,Areadne; Marrero,Yoandra; González,Rogelio; Aldana,Ana I; Moreira,Onidia;
Zootecnia Tropical , 2008,
Abstract: with the objective to evaluate the modulator effect of leucaena leucocephala on the methanogenic bacteria and other microbial groups in the rumen was conducted a trial according to a completely randomized design in a factorial arrangement (4 x 4, four leucaena proportions and four times of fermentation), under in vitro conditions. the trial consisted of four star grass (cynodon nlemfuensis) with leucaena ratios, which were: treatment a=100:0, b=80:20, c=75:25, and d=70:30. the sampling was performed before the incubation (0 hour), and at 4, 8, and 12 h of fermentation. the counts of methanogenic bacteria were 40.22, 38.42, 13.98, and 12.46 x 107 cfu/ml for the treatments a, b, c, and d, respectively. the modulator increased the population of cellulolytic bacteria, compared with the control without supplement, and the best response was found in the ratios 80:20 and 70:30. the populations of cellulolytic fungi were 2.08, 3.49, 3.69, and 4.48 x 103 tfu/ml for a, b, c, and d treatments, respectively. the protoozoa population varied from 1.50 to 2.75 x 105 cell/ml, under the trial conditions. in all cases with l. leucocephala as modulator the populations were significantly small, but the smallest was found when the ratio 80:20 of star grass:modulator was used. it is concluded that the modulator from the fermentation with l. leucocephala is suitable for reducing the population of rumen methanogenic bacteria without affecting the total population of cellulolytic bacteria.
Page 1 /100
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.