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1.
Int J Mol Sci ; 24(14)2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37511251

RESUMO

This study investigated the effects of the Albizia julibrissin Leaf extracts (AJLE) on adipocytes using 3T3-L1 cells. AJLE inhibited adipogenesis by reducing the expression of peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT/enhancer binding proteins (C/EBPs) that regulate enzymes involved in fat synthesis and storage, and subsequently reduced intracellular lipid droplets, glycerol-3-phosphate dehydrogenase (GPDH), and triglyceride (TG). AJLE also increased the expression of brown adipocyte markers, such as uncoupling protein-1 (UCP-1), PR/SET domain 16 (PRDM16), and bone morphogenetic protein 7 (BMP7) by inducing the differentiation of brown adipocytes, as shown by a decrease in the lipid droplet sizes and increasing mitochondrial mass. AJLE increased the expression of transcription factor A, mitochondrial (TFAM), mitochondrial DNA (mtDNA) copy number, and UCP-1 protein expression, all of which are key factors in regulating mitochondrial biogenesis. AJLE-induced browning was shown to be regulated by the coordination of AMPK, p38, and SIRT1 signaling pathways. The ability of AJLE to inhibit adipogenesis and induce brown adipocyte differentiation may help treat obesity and related diseases.


Assuntos
Adipócitos Brancos , Albizzia , Camundongos , Animais , Adipócitos Brancos/metabolismo , Albizzia/genética , Albizzia/metabolismo , Diferenciação Celular , Adipogenia/genética , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Adipócitos Marrons/metabolismo , DNA Mitocondrial/metabolismo , Células 3T3-L1 , PPAR gama/metabolismo
2.
Trop Anim Health Prod ; 54(5): 247, 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35930104

RESUMO

This study aimed to investigate the effect of substitution of siris foliage with alfalfa forage in the diet of fattening lambs on digestibility, fermentation, and growth performance of fattening lambs. In the present experiment, 27 8-month-old Arabi lambs (31.3 ± 6) with an initial weight of 28.8 ± 1.99 kg were used in a completely randomized design. The effect of experimental diets on dry matter intake was not significant; however, the diets had a significant effect on the intake of neutral detergent fiber (NDF), acid detergent fiber (ADF), and crude protein (P < 0.05). The effect of experimental diets on the apparent digestibility of dry matter, organic matter, NDF, ADF, and crude protein was not significant (P < 0.05). Ammonia nitrogen concentration, pH, and a total population of ruminal fluid protozoa and blood parameters were not affected by experimental diets. Parameters of fattening performance such as feed intake, live weight changes, feed conversion ratio, some carcass traits such as mean weight and size of carcass parts, and colorimetric indices of muscle tissue in the order of fattening lambs were not affected by experimental diets. The use of foliage of siris in the diet of fattening lambs as a substitute with part of alfalfa had no adverse effect on the characteristics studied in the present experiment. Therefore, siris be recommended as part of the diet of fattening lambs.


Assuntos
Albizzia , Rúmen , Albizzia/metabolismo , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Detergentes/metabolismo , Detergentes/farmacologia , Dieta/veterinária , Fibras na Dieta/metabolismo , Digestão , Carne , Medicago sativa , Nutrientes , Rúmen/metabolismo , Ovinos , Carneiro Doméstico/metabolismo
3.
J Plant Physiol ; 258-259: 153358, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33453433

RESUMO

Silk tree, Albizia julibrissin Duraz, is an old ornamental plant and extensively cultivated in Asia. Previous works have discovered that the terpenoids were the dominating compounds in the floral VOC of A. julibrissin, however the biosynthesis of these terpenoids was poorly understood so far. Here, 11 terpene synthase genes (TPSs) were identified by transcriptome sequencing that fell into TPS-a, TPS-b and TPS-g subfamilies. The enzymatic activity tests showed that five genes were functional: AjTPS2 was a sesquiterpene synthase and produced α-farnesene and (Z, E)-ß-farnesene; AjTPS5 was able to catalyze the formation of five monoterpenes and nine sesquiterpenes; AjTPS7, AjTPS9 and AjTPS10 were dedicated monoterpene synthases, as AjTPS7 and AjTPS10 formed the single product ß-ocimene and linalool, respectively, and AjTPS9 produced γ-terpinene with other three monoterpenes. More importantly, the main catalytic products of the characterized AjTPSs were consistent with the terpenoids observed in A. julibrissin volatiles. Combining terpene chemistry, TPSs biochemical activities and gene expression analysis, we demonstrate that AjTPS2, AjTPS5, AjTPS7, AjTPS9 and AjTPS10 are responsible for the volatile terpenoids biosynthesis in A. julibrissin.


Assuntos
Albizzia/genética , Alquil e Aril Transferases/genética , Proteínas de Plantas/genética , Terpenos/metabolismo , Albizzia/enzimologia , Albizzia/metabolismo , Alquil e Aril Transferases/metabolismo , Proteínas de Plantas/metabolismo , Compostos Orgânicos Voláteis/metabolismo
4.
Environ Sci Pollut Res Int ; 24(33): 25861-25869, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28936775

RESUMO

Silver nanoparticles synthesized using the leaf extract of Albizia saman (Jacq.) Merr. were tested for induction of cytogenetic abnormality in root tip cells of Drimia indica (Roxb.) Jessop (family Asperagaceae). The leaves are known to be rich in various phytochemicals like flavonoids, glycosides, saponins, steroids, tannins, and terpenoids, which may be responsible for bioreduction, biocapping, and stabilization of nanoparticles. The various instruments used for characterization include UV-VIS spectrophotometer, fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), X-Ray diffractometer (XRD), and high resolution transmission electron microscope (HR-TEM). The present study aims to evaluate the cytotoxic effect of biogenic silver nanoparticles on mitotic chromosomes by using root tip cells of D. indica. The root tips of D. indica was treated with suspensions of silver nanoparticles mixed in distilled water at different concentrations viz., 25, 50, 75, and 100% (w/v) for 6, 12, 18, and 24 h and then fixed in 1:3 ethanol: acetic acid following pre-treatment with 0.05% colchicine for cytological analysis. Silver nanoparticles induced a dose dependent decrease of mitotic index in root meristems. Furthermore, the treated meristem cells showed various types of chromosomal and mitotic aberrations such as anaphase bridge, sticky metaphase, lagging, or forward chromosome indicating genotoxic damage.


Assuntos
Albizzia/metabolismo , Cromossomos de Plantas/efeitos dos fármacos , Drimia/efeitos dos fármacos , Química Verde/métodos , Nanopartículas Metálicas/química , Mitose/efeitos dos fármacos , Prata/química , Aberrações Cromossômicas/induzido quimicamente , Cromossomos de Plantas/genética , Drimia/genética , Meristema/efeitos dos fármacos , Extratos Vegetais/metabolismo , Folhas de Planta/metabolismo , Prata/toxicidade
5.
Nat Prod Res ; 31(17): 1981-1987, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28103742

RESUMO

A new 5-dehydroxyflavan, namely Albiziaflavan B or (+)-(2R, 3S, 4R)-3',4', 7-trihydroxy-4-methoxy-2,3-trans-flavan-3,4-trans-diol (1) was isolated from the root bark of Albizia glaberrima, together with six known compounds including three flavans: (+)-mollisacacidin (2), (+)-fustin (3) and butin (4); two steroids: chondrillasterol (5) and chondrillasterone (6), and a triterpenoid: lupeol (7). The structure of 1 was established by detailed analysis of its spectroscopic data, especially 1D and 2D NMR spectra, HRESIMS and CD data. Compounds 1-6 were assayed for their antiproliferative effects on two human cancer cells, HeLa at 50 µM (n = 2) and HL60 at 20 µM (n = 2). Compound 3 and 4 were the most active on HL60 with IC50 of 8.1 and 8.3 µM, respectively. Compound 6 was the most active with an IC50 of 4.6 µM on HeLa.


Assuntos
Albizzia/metabolismo , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Flavonoides/química , Flavonoides/farmacologia , Esteroides/química , Esteroides/farmacologia , Albizzia/química , Benzopiranos/química , Benzopiranos/isolamento & purificação , Benzopiranos/farmacologia , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Flavonoides/isolamento & purificação , Células HL-60 , Células HeLa , Humanos , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Metabolismo Secundário
6.
J Agric Food Chem ; 64(18): 3514-22, 2016 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-27078512

RESUMO

The seed coat is an external tissue that participates in defense against insects. In some nonhost seeds, including Albizia lebbeck, the insect Callosobruchus maculatus dies during seed coat penetration. We investigated the toxicity of A. lebbeck seed coat proteins to C. maculatus. A chitin-binding protein fraction was isolated from seed coat, and mass spectrometry showed similarity to a C1 cysteine protease. By ELM program an N-glycosylation interaction motif was identified in this protein, and by molecular docking the potential to interact with N-acetylglucosamine (NAG) was shown. The chitin-binding protein fraction was toxic to C. maculatus and was present in larval midgut and feces but not able to hydrolyze larval gut proteins. It did not interfere, though, with the intestinal cell permeability. These results indicate that the toxicity mechanism of this seed coat fraction may be related to its binding to chitin, present in the larvae gut, disturbing nutrient absorption.


Assuntos
Albizzia/química , Quitina/metabolismo , Proteínas de Insetos/metabolismo , Proteínas de Plantas/metabolismo , Gorgulhos/efeitos dos fármacos , Albizzia/metabolismo , Albizzia/parasitologia , Animais , Larva/efeitos dos fármacos , Larva/metabolismo , Proteínas de Plantas/toxicidade , Ligação Proteica , Sementes/química , Sementes/metabolismo , Sementes/parasitologia , Gorgulhos/metabolismo
7.
Int J Phytoremediation ; 18(1): 77-86, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26147743

RESUMO

Toxicity of chromium often impairs the remediation capacity of plants used in phytoremediation of polluted soils. In this study, we have identified Albizia lebbeck as a prospective chromium hyperaccumulator and examined cultivable diversity of endophytes present in chromium-treated and control saplings. High numbers (22-100%) of endophytic bacteria, isolated from root, stem, and leaf tissues, could tolerate elevated (1-3 mM) concentrations of K2CrO7. 16S rRNA gene sequence-based phylogenetic analysis showed that the 118 isolates obtained comprised of 17 operational taxonomic units affiliated with the proteobacterial genera Rhizobium (18%), Marinomonas (1%), Pseudomonas (16%), and Xanthomonas (7%) but also with members of Firmicutes genera, such as Bacillus (35%) and Salinococcus (3%). The novel isolates belonging to Salinococcus and Bacillus could tolerate high K2CrO7 concentrations (3 mM) and also showed elevated activity of chromate reductase. In addition, majority (%) of the endophytic isolates also showed production of indole-3-acetic acid. Taken together, our results indicate that the innate endophytic bacterial community assists plants in reducing heavy metal toxicity.


Assuntos
Albizzia/metabolismo , Bactérias/metabolismo , Cromo/metabolismo , Endófitos/metabolismo , Poluentes do Solo/metabolismo , Bactérias/classificação , Bactérias/genética , Bambusa/metabolismo , Biodegradação Ambiental , DNA Bacteriano/genética , DNA Bacteriano/metabolismo , Endófitos/classificação , Endófitos/genética , Fabaceae/metabolismo , Resíduos Industriais/análise , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Análise de Sequência de DNA , Curtume
8.
Prep Biochem Biotechnol ; 46(2): 192-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26444299

RESUMO

Phytoremediation using timber-yielding tree species is considered to be the most efficient method for chromium/tannery effluent-contaminated sites. In this study, we have chosen Albizzia lebbeck, a chromium hyperaccumulator plant, and studied one of its chromium detoxification processes operated by its endophytic bacterial assemblage. Out of the four different groups of endophytic bacteria comprising Pseudomonas, Rhizobium, Bacillus, and Salinicoccus identified from A. lebbeck employed in phytoremediation of tannery effluent-contaminated soil, Bacillus predominated with three species, which exhibited not only remarkable chromium accumulation ability but also high chromium reductase activity. A chromate reductase was purified to homogeneity from the most efficient chromium accumulator, Bacillus sp. DGV 019, and the purified 34.2-kD enzyme was observed to be stable at temperatures from 20°C to 60°C. The enzyme was active over a wide range of pH values (4.0-9.0). Furthermore, the enzyme activity was enhanced with the electron donors NADH, followed by NADPH, not affected by glutathione and ascorbic acid. Cu(2+) enhanced the activity of the purified enzyme but was inhibited by Zn(2+) and etheylenediamine tetraacetic acid (EDTA). In conclusion, due to its versatile adaptability the chromate reductase can be used for chromium remediation.


Assuntos
Bacillus/enzimologia , Biodegradação Ambiental , Cromo/metabolismo , Oxirredutases/isolamento & purificação , Oxirredutases/metabolismo , Albizzia/metabolismo , Albizzia/microbiologia , Bacillus/genética , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Endófitos , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , RNA Ribossômico 16S , Poluentes do Solo/metabolismo , Temperatura
9.
PLoS One ; 10(11): e0142784, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26559410

RESUMO

We have limited understanding of how tropical canopy foliage varies along environmental gradients, and how this may in turn affect forest processes and functions. Here, we analyse the relationships between canopy leaf area index (LAI) and above ground herbaceous biomass (AGBH) along environmental gradients in a moist forest and miombo woodland in Tanzania. We recorded canopy structure and herbaceous biomass in 100 permanent vegetation plots (20 m × 40 m), stratified by elevation. We quantified tree species richness, evenness, Shannon diversity and predominant height as measures of structural variability, and disturbance (tree stumps), soil nutrients and elevation as indicators of environmental variability. Moist forest and miombo woodland differed substantially with respect to nearly all variables tested. Both structural and environmental variables were found to affect LAI and AGBH, the latter being additionally dependent on LAI in moist forest but not in miombo, where other factors are limiting. Combining structural and environmental predictors yielded the most powerful models. In moist forest, they explained 76% and 25% of deviance in LAI and AGBH, respectively. In miombo woodland, they explained 82% and 45% of deviance in LAI and AGBH. In moist forest, LAI increased non-linearly with predominant height and linearly with tree richness, and decreased with soil nitrogen except under high disturbance. Miombo woodland LAI increased linearly with stem density, soil phosphorous and nitrogen, and decreased linearly with tree species evenness. AGBH in moist forest decreased with LAI at lower elevations whilst increasing slightly at higher elevations. AGBH in miombo woodland increased linearly with soil nitrogen and soil pH. Overall, moist forest plots had denser canopies and lower AGBH compared with miombo plots. Further field studies are encouraged, to disentangle the direct influence of LAI on AGBH from complex interrelationships between stand structure, environmental gradients and disturbance in African forests and woodlands.


Assuntos
Biomassa , Ecossistema , Albizzia/química , Albizzia/metabolismo , Florestas , Folhas de Planta/química , Folhas de Planta/metabolismo , Rhizophoraceae/química , Rhizophoraceae/metabolismo , Solo/química , Tanzânia , Clima Tropical
10.
J Plant Physiol ; 171(14): 1299-305, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25014265

RESUMO

Nitric oxide (NO) is a highly reactive radical that acts as a direct or indirect cellular signalling molecule in plant growth, development and environmental responses. Here we studied the contribution of NO to the control of leaflet movements during nyctinastic closure. For this purpose, we tested the effect of NO donors and an NO scavenger, all supplied in light, on Albizia lophantha leaflet closure after transferral to darkness. Exogenous NO, applied as four donors [sodium nitroprusside (SNP), diethylammonium (Z)-1-(N,N-diethylamino) diazen-1-ium-1,2-diolate (DEA-NONOate), S-nitroso-N-acetylpenicillamine (SNAP) and S-nitrosoglutathione (GS-NO)], inhibited nyctinastic leaflet closure while the application of an NO scavenger [2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO)] plus SNP cancelled the effect of the latter. The inclusion of Nω-nitro-l-arginine methyl ester (l-NAME) or sodium tungstate in the incubation media enhanced nyctinastic closure and also resulted in a decrease in the nitrate plus nitrite released by leaflets into the incubation solution. These results support the notion that NO is involved in regulating the nyctinastic closure of A. lophantha leaflets. Cellular perception of NO did not appear to be mediated by calcium. Pharmacological application of inhibitors of soluble guanylate cyclase (sGC) [1H-[1,2,4]-oxadiazole-[4,3-a]-quinoxalin-1-one (ODQ) and 6-anilino-5,8-quinolinequinone (Ly83583)], phosphodiesterase type 5 (PDE5) (Sildenafil) and the cyclic guanosine monophosphate (cGMP) analogue 8-bromoguanosine-3',5'-cyclomonophosphate sodium salt (8-Br-cGMP) indicated that cGMP was downstream of the NO signalling cascade during nyctinastic closure.


Assuntos
Albizzia/metabolismo , GMP Cíclico/metabolismo , Óxido Nítrico/metabolismo , Folhas de Planta/metabolismo , Transdução de Sinais
11.
J Environ Biol ; 32(2): 173-8, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21882651

RESUMO

Diurnal trends in net photosynthesis rate (P(N)), stomatal conductance (g(s)), water use efficiency (WUE) and biomass were compared in six-month-old seedlings of Albizia lebbeck and Cassia siamea, under different levels of drought stress. The potted plants were subjected to four varying drought treatment by withholding watering for 7 (D1), 14(D2) and 25 (D3) days. The fourth group (C) was watered daily and treated as unstressed (control). Species differed significantly (p < 0.001) in their physiological performance under varying stress conditions. Higher P(N) of 11.6 +/- 0.05 in control followed by 4.35 +/- 0.4 in D1 and 2.83 +/- 0.18 micromol m(-2) s(-1) in D2 was observed in A. lebbeck. A significant (p < 0.001) reduction in P(N) was observed in C. siamea (C 7.65 +/- 0.5 micromol m(-2) s(-1), D1, 2.56 +/- 0.33 micromol m(-2) s(-1) and D2, 1.4 +/- 0.01 micromol m(-2) s(-1)) at 9 hr. A positive correlation was seen between P(N) and g(s) (A. lebbeck, r2 = 0.84; C. siamea, r2 = 0.82). Higher WUE was observed in C. siamea (D2, 7.1 +/- 0.18 micromol m(-2) s(-1); D3, 8.39 +/- 0.11 micromol m(-2) s(-1)) than A. lebbeck, (control, 7.58 +/- 0.3 micromol m(-2) s(-1) and D3, 8.12 +/- 0.15 micromol m(-2) s(-1)). The chlorophyll and relative water content (RWC) was more in A. lebbeck than C. siamea. Maximum biomass was produced by A. lebbeckthan C. siamea. From the study, one could conclude that A. lebbeckis better than C. siamea in adopting suitable resource management strategy and be best suited for the plantation programs in the semi-arid dry lands.


Assuntos
Albizzia/crescimento & desenvolvimento , Biomassa , Cassia/crescimento & desenvolvimento , Secas , Folhas de Planta/crescimento & desenvolvimento , Albizzia/metabolismo , Albizzia/fisiologia , Cassia/metabolismo , Cassia/fisiologia , Clorofila/metabolismo , Ritmo Circadiano , Fotossíntese , Folhas de Planta/metabolismo
12.
Ying Yong Sheng Tai Xue Bao ; 22(5): 1155-61, 2011 May.
Artigo em Chinês | MEDLINE | ID: mdl-21812288

RESUMO

Taking the pot-cultured seedlings of four leguminous tree species (Albizia julibrissin, Robinia pseudoacacia, Sophora japonica, and Gleditsia sinensis) as test materials, this paper studied their growth indices, critical salt concentration (C50), and K+ and Na+ allocation under different levels of NaCl stress, aimed to understand the difference of test tree species in salt tolerance. NaCl stress inhibited the seedling growth of the tree species. Under NaCl stress, the dry matter accumulation decreased, while the root/shoot ratio increased, especially for A. julibrissin and G. sinensis. Quadratic regression analysis showed that the C50 of A. julibrissin, R. pseudoacacia, S. japonica, and G. sinensis was 3.0 per thousand, 5.0 per thousand, 4.5 per thousand, and 3.9 per thousand, respectively, i.e., the salt tolerance of the four tree species was in the order of R. pseudoacacia > S. japonica > G. sinensis > A. julibrissin. In the root, stem, and leaf of the four tree species seedlings, the Na+ content increased with the increase of NaCl stress, while the K+ content (except in the root of A. julibrissin) decreased after an initial increase, resulting in a larger difference in the K+/Na+ ratio in the organs. Under the same NaCl stress, the allocation of Na+ in different organs of the four tree species seedlings decreased in the order of root>stem>leaf, while that of K+ differed with tree species and NaCl stress, and leaf was the main storage organ for K+. The K+/Na+ ratio in different organs decreased in the sequence of leaf>stem>root. R. pseudoacacia under NaCl stress accumulated more K+ and less Na+ in stem and leaf, and had higher K+/Na+ ratio in all organs and higher dry mass, being assessed to be more salt-tolerant. In contrast, A. julibrissin under high NaCl stress accumulated more Na+ in stem and leaf, and had a lower K+/Na+ ratio in all organs and lower dry mass, being evaluated to be lesser salt-tolerant. The K+ accumulation in seedling stem and leaf and the Na+ retention in seedling root could be the main reasons for the salt tolerance of leguminous tree species under NaCl stress.


Assuntos
Fabaceae/crescimento & desenvolvimento , Potássio/metabolismo , Plântula/crescimento & desenvolvimento , Cloreto de Sódio/farmacologia , Sódio/metabolismo , Albizzia/crescimento & desenvolvimento , Albizzia/metabolismo , Fabaceae/metabolismo , Gleditsia/crescimento & desenvolvimento , Gleditsia/metabolismo , Robinia/crescimento & desenvolvimento , Robinia/metabolismo , Tolerância ao Sal/fisiologia , Plântula/metabolismo , Cloreto de Sódio/metabolismo , Sophora/crescimento & desenvolvimento , Sophora/metabolismo , Estresse Fisiológico
13.
J Pharm Biomed Anal ; 55(5): 996-1009, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21530133

RESUMO

Ultra high-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry (UHPLC/ESI-Q-TOF-MS/MS) was applied to separate and identify triterpenoid saponins in crude extract from the stem bark of Albizia julibrissin Durazz. The molecular weights were determined by comparing quasi-molecular ions [M+NH(4)](+) in positive mode and [M-H](-) and [M-2H](2-) ions in negative mode. The MS/MS spectra of the [M-H](-) ions for saponins provided a wealth of structural information related to aglycone skeletons, sugar types and linked sequence. On the basis of the fragmentation behavior of known saponins isolated before, saponins from this plant were identified, even though references were not available. As a result, a total of twenty-eight saponins in the crude extract were identified, which all had a common basic skeleton of the triterpene oleanolic acid and eight of them were new compounds.


Assuntos
Albizzia/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Saponinas/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Terpenos/análise , Cromatografia Líquida/métodos , Misturas Complexas/análise , Eletrólitos , Íons , Espectrometria de Massas/métodos , Modelos Químicos , Ácido Oleanólico/análise , Extratos Vegetais/análise , Espectrometria de Massas em Tandem/métodos
14.
Biosci Biotechnol Biochem ; 72(11): 2867-76, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18997427

RESUMO

Albizzia saman, a leguminous plant, is known to open its leaves in the daytime and sleep at night with the leaves folded. beta-D-Glucopyranosyl 12-hydroxyjasmonate (1) was isolated as an endogenous chemical factor controlling this leafmovement. We developed a concise synthesis of optically pure (-)-1 in 9 steps from (+)-2 with a total yield of 58%. Similarly, such analogs of 1 as epi-LCF (13), enantiomer (14), and galactoside (19) were synthesized for a structure activity relationship (SAR) study. The results of this SAR study strongly suggest that the mechanism for the leaf-closing activity of 1 would be different from that of methyl jasmonate, and also suggest the involvement of a different kind of target protein which recognizes the trans-isomer of a jasmonate derivative.


Assuntos
Ciclopentanos/síntese química , Ciclopentanos/metabolismo , Glucosídeos/síntese química , Glucosídeos/metabolismo , Oxilipinas/síntese química , Oxilipinas/metabolismo , Albizzia/metabolismo , Ciclopentanos/química , Glucosídeos/química , Glicosilação , Oxilipinas/química , Estereoisomerismo , Relação Estrutura-Atividade , Especificidade por Substrato
15.
Biotechnol Lett ; 30(8): 1495-9, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18368297

RESUMO

A purification protocol, involving water extraction, ammonium sulfate precipitation, Sepharose 4B-trypsin affinity and FPLC Superdex G-75 chromatography, was employed to isolate a trypsin inhibitor from Albizzia kalkora seeds. The inhibitor, which had a molecular mass of 19,768.23 Da, consisted of two disulfide-linked polypeptide chains with approximate molecular mass of 15.5 and 4.5 kDa, respectively. It was stable from pH 2-12 for 24 h, whereas it was unstable either above 80 degrees C for 10 min or under reduced condition over 60 min. The inhibitor, which inhibited trypsin activity with an apparent K (i) of 2.5 x 10(-7) M, had one reactive site involved with a lysine residue. Disulfide linkage and lysine residue were important in maintaining its active conformation. Partial amino acid sequence of the purified protein showed a high degree of homology with various members of the Kunitz inhibitor family. Moreover, trypsin-like proteases from larval Helicoverpa armigera, Spodoptera exigua, and Pieris rapae were inhibited for 85, 57, and 68% respectively, by the inhibitor at 45 microg ml(-1).


Assuntos
Albizzia/metabolismo , Sistema Digestório/enzimologia , Insetos/enzimologia , Peptídeo Hidrolases/metabolismo , Peptídeos/isolamento & purificação , Proteínas de Plantas/isolamento & purificação , Inibidores de Proteases/farmacologia , Albizzia/efeitos dos fármacos , Animais , Sistema Digestório/efeitos dos fármacos , Eletroforese em Gel de Poliacrilamida , Insetos/efeitos dos fármacos , Sementes/efeitos dos fármacos , Sementes/metabolismo , Espectrometria de Fluorescência , Termodinâmica , Titulometria
16.
Bioresour Technol ; 98(1): 198-201, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16473002

RESUMO

Investigations were made to test the larval toxicity and smoke repellent potential of Albizzia amara and Ocimum basilicum at different concentration (2%, 4%, 6%, 8% and 10%) against the different instar (I, II, III and IV) larvae and pupae of Aedes aegypti. The LC50 values of A. amara and O. basilicum for I instar larvae was 5.412 and 3.734, II instar 6.480 and 4.154, III instar 7.106 and 4.664, IV instar 7.515 and 5.124, respectively. The LC50 and LC90 values of pupae were 6.792%, 5.449% and 16.925%, 15.474%. The smoke toxicity of A. amara was more effective against A. aegypti than the O. basilicum.


Assuntos
Aedes/efeitos dos fármacos , Albizzia/metabolismo , Repelentes de Insetos/metabolismo , Inseticidas/metabolismo , Ocimum basilicum/metabolismo , Controle Biológico de Vetores/métodos , Animais , Relação Dose-Resposta a Droga , Larva/efeitos dos fármacos , Dose Letal Mediana , Pupa/efeitos dos fármacos
17.
Am J Primatol ; 68(2): 143-51, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16429414

RESUMO

The selective ingestion of plant gum exudates by chimpanzees has been frequently observed at various study sites. At Bossou, Guinea, chimpanzees also frequently ingest Albizia zygia gum exudate. A functional explanation for this behavior is lacking, so we evaluated its possible contribution of energy in the form of short-chain fatty acids (SCFA) as well as minerals. An in vitro fermentation study of A. zygia gum using the fecal bacteria of a Bossou chimpanzee showed that carboxylic acids were produced with a 6-hr lag phase up to 44 mmol/l by 18 hr of incubation. Acetate was the most abundant acid produced, followed by lactate and propionate. The energy supplied from the fermentation of a piece of gum exudate (20-30 g) was negligible in comparison with the estimated daily energy requirements of chimpanzees in the wild. However, A. zygia gum exudate (20-30 g) can supply sufficient amounts of calcium, manganese, magnesium, and potassium to fulfill the daily requirements for these minerals in chimpanzees.


Assuntos
Albizzia/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Comportamento Alimentar , Preferências Alimentares , Pan troglodytes/metabolismo , Resinas Vegetais/metabolismo , Albizzia/química , Animais , Animais Selvagens/metabolismo , Bactérias , Metabolismo Energético , Fezes/microbiologia , Fermentação , Guiné , Resinas Vegetais/química
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