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1.
Bioengineered ; 11(1): 1159-1169, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33084492

RESUMO

Tan sheep is an indigenous ovine breed of China known for its high meat quality and pleasing taste. Seven herbs of traditional Chinese medicine, namely, Ephedra sinica, Glycyrrhiza uralensis, Caragana korshinskii, Allium mongolicum, Thymus vulgaris, Astragalus membranaceus, and Lespedeza bicolor are commonly grazed by Tan sheep. It has been widely believed that these herbs are of high nutritive value, which may significantly contribute to the high meat quality and distinct flavor of Tan sheep. However, the nutritive values of these herbs have not been evaluated to date. In this study, samples of the seven herbs were collected from the steppe of Yanchi County of Ningxia Autonomous Region of China. The dry matter (DM), crude protein (CP), ether extract (EE), ash (Ash), calcium (Ca), phosphorus (P), neutral detergent fiber (NDF), and acid detergent fiber (ADF) of these herbs were measured using locally cultivated alfalfa as the standard forage. Digestion of the dry matter, neutral detergent fiber, acid detergent fiber, and crude protein in the rumen of Tan sheep was examined using the nylon bag method, in order to evaluate their feeding nutritional value. Our results show that all the seven herbs meet the nutritional needs of ruminants based on the standard forage alfalfa. However, Ephedra, Glycyrrhiza, Caragana, Allium, Astragalus, and Lespedeza have higher nutritive value than Thymus (P < 0.05). According to the ruminal degradation rates of dry matter, neutral detergent fiber, acid detergent fiber, and crude protein, the nutritive value of Caragana, Allium, and Lespedeza is higher than that of Ephedra, Glycyrrhiza, Astragalus, and Thymus (P < 0.05). The overall nutritive value of Allium is the highest among the seven herbs and therefore Allium is recommended to better meet the nutritional needs of Tan sheep.


Assuntos
Valor Nutritivo , Allium/metabolismo , Animais , Cálcio/metabolismo , Caragana/metabolismo , Ephedra/metabolismo , Glycyrrhiza/metabolismo , Lespedeza/metabolismo , Ovinos
2.
J Photochem Photobiol B ; 210: 111984, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32771914

RESUMO

This work reported the preparation, characterization, cytotoxicity of green synthesized Lespedeza cuneate mediated silver nanoparticles (Lc-AgNPs) and graphene oxide­silver nanocomposite (GO-AgNComp) using Lc-AgNPs. The UV absorption spectrum at 419 nm indicated the successful formation of GO-AgNComp. The TEM analysis displayed the thin sheet of graphene decorated Lc-AgNPs in GO-AgNComp. Zeta potential was -13.2 mV for Lc-AgNPs and -30.5 mV for GO-AgNComp. The photothermal conversion efficiency was calculated as 31.09% for GO-AgNComp. The negatively charged zeta potential of GO-AgNComp enhanced its cellular penetration through enhanced permeability and retention (EPR) effect. The near-infrared laser (NIR) induced the anticancer activity of Lc-AgNPs and GO-AgNComp in human lung cancer cells (A549) and brain tumour (LN229). The results indicated that about 50% of A549 cells and LN229 cells were ablated by treatment of 24.73 ± 2.98 µg/mL and 27.34 ± 1.62 µg/mL of Lc-AgNPs, as well by 15.46 ± 2.31 µg/mL and 20.95 ± 1.35 µg/mL of GO-AgNComp respectively. Moreover, GO-AgNComp was not cytotoxic to normal mouse fibroblast cells (NIH3T3), but it caused the cancer cell death in A549 and LN229 through ROS generation, nuclear damage, and mitochondrial membrane potential (∆ψm) loss. This work reported the anticancer potential of GO-AgNComp, which deserves further study on the molecular elucidation of GO-AgNComp mediated human lung and tumour therapy.


Assuntos
Antineoplásicos/química , Grafite/química , Nanocompostos/química , Prata/química , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Química Verde , Humanos , Lespedeza/química , Lespedeza/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Células NIH 3T3 , Nanocompostos/uso terapêutico , Nanocompostos/toxicidade , Tamanho da Partícula , Extratos Vegetais/química , Espécies Reativas de Oxigênio/metabolismo
3.
Am J Bot ; 105(12): 1975-1985, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30512197

RESUMO

PREMISE OF THE STUDY: Herb chronology, the study of belowground annual growth rings in perennial forbs, has much potential as a tool for monitoring plant growth as a function of environment. To harness this potential, understanding of the coordination between ring ontogeny, aboveground phenology, and the temporal allocation of carbon products belowground in herbaceous forbs must be improved. METHODS: We investigated these relationships in two southern United States tallgrass prairie perennial forb species, Asclepias viridis and Lespedeza stuevei, making monthly excavations for a year. KEY RESULTS: Belowground xylogenesis began when starch reserves were at their seasonal low in the spring as shoots reached maximum height. The highest relative radial growth of the ring occurred concurrently with replenishment of root starch reserves in early summer. Xylogenesis concluded with leaf senescence in late summer and belowground starch reserves near saturation. CONCLUSIONS: By demonstrating that ring ontogeny is tied to early summer starch replenishment, our results illustrate the mechanisms behind previous findings where ring width was highly correlated with summer climatic conditions for these two species. This study provides a new physiological link between how ring chronologies in herbs often accord with growing-season environment; further dissecting this phenomenon is vital in unlocking the potential of herb chronology.


Assuntos
Asclepias/crescimento & desenvolvimento , Lespedeza/crescimento & desenvolvimento , Raízes de Plantas/crescimento & desenvolvimento , Amido/metabolismo , Xilema/crescimento & desenvolvimento , Asclepias/metabolismo , Pradaria , Lespedeza/metabolismo , Raízes de Plantas/metabolismo
4.
Phytomedicine ; 36: 26-36, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29157823

RESUMO

BACKGROUND: Lespedeza species have been used as a traditional medicine to treat nephritis, azotemia, inflammation, energy depletion, diabetes, and diuresis. PURPOSE: The purpose of this study is to screen the most potent Lespedeza species against methylglyoxal (MGO)-induced glucotoxicity, and to elucidate the mechanisms of action. Also, we will attempt to identify small chemical metabolites that might be responsible for such anti-glucotoxicity effects. METHODS: Firstly, the protective effect of 26 different Lespedeza species against MGO-induced toxicity in human umbilical vein endothelial cells was investigated. The chemical metabolites of the most potent species (Lespedeza bicolor 1 (LB1) were identified by high pressure liquid chromatography quadrupole time-of-flight tandem mass spectrometry (HPLC-Q-TOF-MS/MS), then quantified by HPLC. The effects of LB1 on MGO-induced apoptosis were measured by annexin V-FITC staining and western blot. Inhibitory effects of LB1 on MGO-induced ROS generation, and effect of LB1 on advanced glycation end products (AGEs) inhibitor or a glycated cross-link breaker are also measured. RESULTS: Among different Lespedeza species, LB1 extract was shown to reduce intracellular reactive oxidative species, exhibit anti-apoptotic effects, strongly inhibit all the mitogen-activated protein kinase signals, inhibit MGO-induced AGEs formation, and break down preformed AGEs. We tentatively identified 17 chemical constituents of LB1 by HPLC-Q-TOF-MS/MS. Among those, some components, such as genistein and quercetin, significantly reduced the AGEs formation and increased the AGEs-breaking activity, resulting in the reduction of glucotoxicity. CONCLUSION: LB1 extract has shown to be effective in preventing or treating MGO-induced endothelial dysfunction.


Assuntos
Lespedeza/química , Extratos Vegetais/farmacologia , Aldeído Pirúvico/toxicidade , Apoptose/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Avaliação Pré-Clínica de Medicamentos/métodos , Genisteína/análise , Genisteína/farmacologia , Produtos Finais de Glicação Avançada/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Lespedeza/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Extratos Vegetais/química , Plantas Medicinais/química , Quercetina/análise , Quercetina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Espectrometria de Massas em Tandem
5.
J Agric Food Chem ; 63(38): 8631-9, 2015 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-26345477

RESUMO

Lespedeza species are useful for pasture and energy crops as well as medical plants. We determined the metabolites discriminated from the each growth period (3, 4, 6, 8, 15, and 18 months) after germination in leaves and stems of Lespedeza maximowizii by a metabolomics technique. Specifically, levels of sugars and luteolin-dominated derivatives were significantly elevated in samples harvested in November. This may be related to the cold tolerance mechanism against the low temperatures of the winter season. The concentrations of secondary metabolites, isoflavones and flavanones, as well as tyrosinase inhibitory activity were the highest in the 6 month samples, which were harvested in September, during the fall season. The tyrosinase inhibitory activity in leaves was higher than that in stems irrespective of the growth period. This study suggests that mass spectrometry-based metabolite profiling could be used as a tool to examine quantitative or qualitative metabolite changes related to seasonal variations and to understand the correlation between activity and metabolites.


Assuntos
Inibidores Enzimáticos/análise , Lespedeza/química , Lespedeza/crescimento & desenvolvimento , Monofenol Mono-Oxigenase/antagonistas & inibidores , Extratos Vegetais/análise , Agaricales/química , Agaricales/enzimologia , Inibidores Enzimáticos/metabolismo , Lespedeza/metabolismo , Metaboloma , Monofenol Mono-Oxigenase/análise , Extratos Vegetais/metabolismo , Estações do Ano
6.
Vet Parasitol ; 191(1-2): 51-8, 2013 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-22985929

RESUMO

Feeding sun-dried sericea lespedeza [SL; Lespedeza cuneata (Dum-Cours.) G. Don.] reduces gastrointestinal nematode (GIN) infection in goats fed in confinement, but effects of this forage when fed as a supplement to goats on pasture are unclear. A study was completed in which supplemental feeds (75 and 95% SL leaf meal pellets and a commercial pellet, all fed at 0.91 kg/head/day) were offered to thirty growing male Spanish goats (9 months old, 20.6 ± 2.8 kg, 10/treatment) grazing perennial warm-season grass pastures in Fort Valley, GA, from September to November, 2010. Fecal and blood samples were taken from individual animals weekly to determine fecal egg count (FEC) and packed cell volume (PCV), respectively, and animal weights were recorded at the start and end of the trial. After 11 weeks grazing, animals were slaughtered for recovery, counting, and speciation of adult GIN from the abomasum and small intestines. There was no difference in FEC between goats fed the 75 and 95% SL leaf meal pellets, but both groups had lower (P<0.05) FEC than the goats fed the commercial pellets from days 35 to 77. The PCV values were not affected by the dietary treatments. Animal gain per day averaged 102.0, 77.2, and 53.3g for goats fed 95% SL, commercial, and 75% SL pellets, respectively (P<0.05). The 95% SL leaf meal pellet goats had 93.0 and 47.3% fewer (P<0.05) total (male+female) adult Haemonchus contortus and Teladorsagia circumcincta, respectively, than control animals, while only male H. contortus were lower (47.6%; P<0.05) in 75% SL-fed goats compared with commercial pellet-fed animals. Feeding supplemental SL leaf meal pellets improved animal performance (95% SL pellets) and reduced worm burdens (75 and 95% SL pellets) in young grazing goats and is a useful tool for natural GIN control in small ruminants.


Assuntos
Suplementos Nutricionais , Doenças das Cabras/terapia , Lespedeza/metabolismo , Infecções por Nematoides/veterinária , Folhas de Planta , Abomaso/parasitologia , Animais , Peso Corporal , Dieta/veterinária , Fezes/parasitologia , Feminino , Cabras , Hematócrito , Intestino Delgado/parasitologia , Masculino , Infecções por Nematoides/terapia , Contagem de Ovos de Parasitas
7.
Plant Cell Rep ; 31(11): 2085-97, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22847333

RESUMO

In this study, 39 specimens belonging to Lespedeza species (Lespedeza cyrtobotrya, L. bicolor, L. maximowiczii, and Lespedeza cuneata) (Leguminosae) were classified phenotypically and genotypically. We constructed a phylogenetic tree based on the combined nrDNA (internal transcribed spacer; ITS) and cpDNA (trnL-trnF) sequences with the aim of classifying the genotypes. Samples were mainly divided into three genotypes. Samples of L. cyrtobotrya and L. bicolor were mixed in a single branch, whereas samples of L. maximowiczii and L. cuneata were clustered within species, respectively. We performed a liquid chromatography-electrospray ionization-mass spectrometry-based metabolite profiling analysis to classify the phenotypes. Multivariate statistical analyses such as principal component analysis (PCA) and hierarchical clustering analysis (HCA) were used for the clustering pattern analysis and distance analysis between species, respectively. According to the PCA and HCA results, leaves were classified into four phenotypes according to species. In both the genetic and chemotaxonomic classification methods, the distance between L. cyrtobotrya and L. bicolor was the closest between species, and L. cuneata was the farthest away from the other three species. Additionally, orthogonal partial least squares-discriminant analysis was employed to identify significantly different phytochemicals between species. We classified L. cyrtobotrya and L. bicolor by identifying significantly different phytochemicals. Interestingly, leaves and stems showed different phenotypic classifications based on the chemotaxonomic classification. Stem samples of the other three species were mixed regardless of species, whereas L. cyrtobotrya stem samples were clustered within species. The phenotypic classification of leaves coincided more with the genotypic classification than that of stems. Key message We classified four wild-type Lespedeza sp. by analyzing the combined nrDNA (ITS) and cpDNA (trnL-trnF) sequences. We also classified leaves and stems of Lespedeza sp. by applying liquid chromatography-mass spectroscopy-based metabolite profiling.


Assuntos
Lespedeza/classificação , Metaboloma , Extratos Vegetais/química , Cromatografia Líquida de Alta Pressão , Análise por Conglomerados , DNA de Cloroplastos/química , DNA de Cloroplastos/genética , DNA de Plantas/química , DNA de Plantas/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Análise Discriminante , Genótipo , Análise dos Mínimos Quadrados , Lespedeza/química , Lespedeza/genética , Lespedeza/metabolismo , Metabolômica , Análise Multivariada , Fenótipo , Filogenia , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Folhas de Planta/classificação , Folhas de Planta/genética , Folhas de Planta/metabolismo , Caules de Planta/química , Caules de Planta/classificação , Caules de Planta/genética , Caules de Planta/metabolismo , Análise de Componente Principal , Análise de Sequência de DNA , Especificidade da Espécie , Espectrometria de Massas por Ionização por Electrospray
8.
J Agric Food Chem ; 60(15): 3934-9, 2012 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-22432963

RESUMO

This research assessed the utilization of sericea lespedeza (SL, Lespedeza cuneata ) hay, a highly condensed tannin (CT) forage (87-181 g CT/kg), as a dietary regimen of meat goats, and thereby the effects on physicochemical properties of goat meat (chevon) and flavor compounds in cooked chevon chops were evaluated. Although it is commonly believed that higher amounts of CT can have deleterious effects on animal performance due to low digestibility and low voluntary intakes in ruminants, feeding meat goats with SL hay increased the body weight compared to goats fed bermudagrass hay without altering the chemical composition and meat quality of chevon. Feeding SL hay to meat goats also did not significantly influence the flavor volatiles in cooked chevon chops. The findings indicate that SL hay can be used as a low-input forage to replace expensive forages.


Assuntos
Ração Animal/análise , Aromatizantes/análise , Cabras/metabolismo , Lespedeza/química , Carne/análise , Proantocianidinas/análise , Animais , Culinária , Aromatizantes/metabolismo , Lespedeza/metabolismo , Proantocianidinas/metabolismo , Controle de Qualidade
9.
Bioprocess Biosyst Eng ; 34(3): 357-65, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21153422

RESUMO

The cellulase production by Trichoderma viride, cultivated on different substrates, namely steam-pretreated Lespedeza, filter paper, microcrystalline cellulose (MCC) or carboxymethyl cellulose (CMC), was studied. Different cellulase systems were secreted when cultivated on different substrates. The cellulolytic enzyme from steam-pretreated Lespedeza medium performed the highest filter paper activity, exoglucanase and endoglucanase activities, while the highest ß-glucosidase activity was obtained from the enzyme produced on filter paper medium. The hydrolytic potential of the enzymes produced from different media was evaluated on steam-pretreated Lespedeza. The cellulase from steam-pretreated Lespedeza was found to have the most efficient hydrolysis capability to this specific substrate. The molecular weights of the cellulases produced on steam-pretreated Lespedeza, filter paper and MCC media were 33, 37 and 40 kDa, respectively, and the cellulase from CMC medium had molecular weights of 20 and 43 kDa. The degree of polymerization, crystallinity index and micro structure scanned by the scanning electron microscopy of degraded steam-pretreated Lespedeza residues were also studied.


Assuntos
Celulases/metabolismo , Celulose/análise , Celulose/metabolismo , Lespedeza/química , Trichoderma/enzimologia , Carboidratos/química , Carboximetilcelulose Sódica/análise , Carboximetilcelulose Sódica/metabolismo , Celulase/análise , Celulase/biossíntese , Celulase/metabolismo , Celulases/biossíntese , Celulose/ultraestrutura , Glucana 1,3-beta-Glucosidase/análise , Glucana 1,3-beta-Glucosidase/biossíntese , Glucana 1,3-beta-Glucosidase/metabolismo , Hidrólise , Lespedeza/metabolismo , Lespedeza/ultraestrutura , Papel , Polimerização , Vapor , Especificidade por Substrato , Trichoderma/metabolismo , Difração de Raios X/métodos , beta-Glucosidase/análise , beta-Glucosidase/biossíntese , beta-Glucosidase/metabolismo
10.
Ecology ; 90(7): 1810-20, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19694130

RESUMO

Plant species composition and diversity is often influenced by early life history stages; thus, global change could dramatically affect plant community structure by altering seed production. Unfortunately, plant reproductive responses to global change are rarely studied in field settings, making it difficult to assess this possibility. To address this issue, we quantified the effects of elevated CO2, nitrogen deposition, and declining diversity on inflorescence production and inflorescence mass of 11 perennial grassland species in central Minnesota, U.S.A. We analyzed these data to ask whether (1) global change differentially affects seed production of co-occurring species; (2) seed production responses to global change are similar for species within the same functional group (defined by ecophysiology and growth form); and (3) seed production responses to global change match productivity responses: We found that, on average, allocation to seed production decreased under elevated CO2, although individual species responses were rarely significant due to low power (CO2 treatment df = 2). The effects of nitrogen deposition on seed production were similar within functional groups: C4 grasses tended to increase while C3 grasses tended to decrease allocation to seed production. Responses to nitrogen deposition were negatively correlated to productivity responses, suggesting a trade-off. Allocation to seed production of some species responded to a diversity gradient, but responses were uncorrelated to productivity responses and not similar within functional groups. Presumably, species richness has complex effects on the biotic and abiotic variables that influence seed production. In total, our results suggest that seed production of co-occurring species will be altered by global change, which may affect plant communities in unpredictable ways. Although functional groups could be used to generalize seed production responses to nitrogen deposition in Minnesota prairies, we caution against relying on them for predictive purposes without a mechanistic understanding of how resource availability and biotic interactions affect seed production.


Assuntos
Dióxido de Carbono/química , Dióxido de Carbono/metabolismo , Ecossistema , Nitrogênio/química , Nitrogênio/metabolismo , Sementes/fisiologia , Lespedeza/metabolismo , Lupinus/metabolismo , Minnesota , Modelos Biológicos , Poaceae/metabolismo , Reprodução/fisiologia , Solo/análise , Solidago/metabolismo
11.
J Anim Sci ; 87(2): 761-9, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18849376

RESUMO

We tested the hypothesis that supplemental polyethylene glycol (PEG), a polymer that neutralizes the effects of tannins, would increase intake and preference of cattle for fresh-cut sericea lespedeza (SL; Lespedeza cuneata), a legume with high concentrations of condensed tannins. Sixteen crossbred steers (initial BW of 249 +/- 6.6 kg) were randomly assigned to 2 treatments: 1) grain supplement with PEG (PEG-S) and 2) grain supplement without PEG (control). To assess intake, we conducted a trial with 6 sample periods, each 6 d in duration, with steers fed SL and prairie hay (PH) in separate meals. Steers were fasted overnight and fed their respective supplements (with and without PEG) at 0800 h. Animals were then offered fresh-cut SL from 1050 to 1550 h, PH was fed from 1600 to 2000 h, and they were without food from 2000 to 0800 h the next day. To assess preference, we conducted 1-d tests in which steers had simultaneous access to SL and PH on the day following periods 2 to 6. As with the intake experiment, steers were fasted overnight and fed their respective supplements at 0800 h, but from 1050 to 1250 h all steers had access to SL and PH simultaneously. We weighed steers before and at the completion of the study and calculated ADG. Steers treated with PEG consumed more SL per unit of BW than control steers in periods 2 to 6 (period x treatment interaction, P < 0.001). In contrast, controls consumed more PH than steers given PEG (period x treatment x day interaction, P = 0.009). The PEG-S steers consumed more total DM (SL + PH) than controls in periods 3, 5, and 6 but not in periods 1, 2, and 4 (period x treatment interaction, P = 0.004). Sericea lespedeza intake as a percentage of total DMI was greater for the PEG-S steers every day except d 1 and 2 of period 1 (period x treatment x day interaction, P = 0.03). Averaged across the 5 preference tests, PEG-S steers selected a greater proportion of SL than did control steers (39 vs. 9%), and the magnitude of the difference was greater in the later tests (test x treatment interaction, P = 0.004). The PEG-S steers had greater ADG than controls (0.44 vs. 0.24 kg/d; P = 0.005). Our results indicate PEG increases intake of and preference for SL and suggest that PEG supplementation of cattle may increase intake of SL and improve ADG in pastures that contain SL.


Assuntos
Bovinos/fisiologia , Suplementos Nutricionais , Lespedeza/metabolismo , Polietilenoglicóis/administração & dosagem , Ração Animal/análise , Animais , Bovinos/crescimento & desenvolvimento , Bovinos/metabolismo , Ingestão de Alimentos/fisiologia , Preferências Alimentares/fisiologia , Lespedeza/química , Masculino , Proantocianidinas/análise , Distribuição Aleatória , Aumento de Peso/fisiologia
12.
J Microbiol Biotechnol ; 18(5): 874-9, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18633284

RESUMO

Tyrosinase is a key enzyme for melanin biosynthesis, and hyperpigmentation disorders are associated with abnormal accumulation of melanin pigments, which can be reduced by treatment with depigmenting agents. The methanol extract of Lespedeza cyrtobotrya MIQ showed inhibitory activity against mushroom tyrosinase. The active compound was purified from the methanol extract of L cyrtobotrya, followed by several chromatographic methods, and identified as dalbergioidin (DBG) by spectroscopic methods. The results showed that DBG exhibited tyrosinase inhibitory activity with an IC50 of 20 mM. The kinetic analysis tyrosinase inhibition revealed that DBG acted as noncompetitive inhibitor. In addition, DBG showed a melanin biosynthesis inhibition zone in the culture plate of Streptomyces bikiniensis that has commonly been used as an indicator organism. Furthermore, 27 mM DBG decreased more than 50% of melanin contents on the pigmentation using immortalized mouse melanocyte, melan-a cell.


Assuntos
Agaricales/enzimologia , Cromonas/farmacologia , Inibidores Enzimáticos/farmacologia , Lespedeza/metabolismo , Melaninas/biossíntese , Monofenol Mono-Oxigenase/antagonistas & inibidores , Extratos Vegetais/farmacologia , Caules de Planta/metabolismo , Agaricales/efeitos dos fármacos , Agaricales/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Cromonas/química , Cromonas/isolamento & purificação , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Proteínas Fúngicas/antagonistas & inibidores , Proteínas Fúngicas/metabolismo , Humanos , Cinética , Lespedeza/química , Melaninas/antagonistas & inibidores , Melanócitos/efeitos dos fármacos , Melanócitos/fisiologia , Monofenol Mono-Oxigenase/metabolismo , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Caules de Planta/química , Streptomyces/efeitos dos fármacos , Streptomyces/metabolismo
13.
Oecologia ; 153(2): 261-72, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17479294

RESUMO

Water availability strongly governs grassland primary productivity, yet this resource varies dramatically in time (seasonally) and space (with soil depth and topography). It has long been assumed that co-occurring species differ in their partitioning of water use by depth, but direct evidence is lacking. We report data from two growing seasons (2004-2005) in which we measured the isotopic signature of plant xylem water from seven species (including C(3) forbs and shrubs and C(4) grasses) growing along a topographic gradient at the Konza Prairie Biological Station. Plant xylem stable oxygen isotope ratio (delta(18)O) values were compared to soil water delta(18)O profiles, recent rainfall events, and groundwater. Species varied in both their temporal patterns of water use and their responses to seasonal droughts in both years. During wet periods, species differences in water use were minimal, with common dependency on recent rainfall events stored in the upper soil layers. However, during dry periods, most C(3) species used proportionally more water from deeper portions of the soil profile relative to the C(4) grasses. Plants in uplands used more shallow soil water compared to those in lowlands, with the greatest differences across the topographic gradient occurring during dry periods. While the documented vertical root distribution varies by species and growth form in this grassland, each of the species we measured appeared to compete for the same surface layer soil moisture when water was not limiting. Thus, our results suggest that variation in precipitation history and landscape positions are greater determinants of water-use patterns than would be expected based on absolute rooting depth.


Assuntos
Ecossistema , Raízes de Plantas/crescimento & desenvolvimento , Poaceae/crescimento & desenvolvimento , Poaceae/metabolismo , Água/metabolismo , Ceanothus/crescimento & desenvolvimento , Ceanothus/metabolismo , Kansas , Lespedeza/crescimento & desenvolvimento , Lespedeza/metabolismo , Chuva , Solo , Vernonia/crescimento & desenvolvimento , Vernonia/metabolismo
14.
Sheng Wu Gong Cheng Xue Bao ; 22(6): 940-4, 2006 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-17168316

RESUMO

The Bacillus subtilis Sac B gene with the vacuolar targeting signal sequence driven by 35S promotor was transferred into Lespedeza thunbergii by Agrobacterium mediated method. Total 62 Kan-resistant plants were obtained, of which 5 plants were proved to be transgenic plants. The transgenic plants were characterized by PCR amplification, PCR-Southern hybridization and RT-PCR. The physiological assay results showed that the transgenic plants were more tolerant to stress than the controls under the condition of 200mmol/L NaCl and 5% PEG, respectively, and that the content of soluble sugar in trnsgenic plants was significantly higher than that of controls in the period of tests (5-15 days) under salt and PEG stress.


Assuntos
Bacillus subtilis/enzimologia , Bacillus subtilis/genética , Hexosiltransferases/genética , Lespedeza/genética , Metabolismo dos Carboidratos , Carboidratos/química , Lespedeza/efeitos dos fármacos , Lespedeza/crescimento & desenvolvimento , Lespedeza/metabolismo , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Cloreto de Sódio/farmacologia , Solubilidade , Estresse Fisiológico/efeitos dos fármacos , Transformação Genética , Transgenes/genética
15.
J Anim Sci ; 83(1): 182-6, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15583058

RESUMO

The objective of this study was to compare methane emission by goats consuming the condensed tannin-containing forage sericea lespedeza (Les-pedeza cuneata) or a mixture of crabgrass (Digitaria ischaemum) and Kentucky 31 tall fescue (Festuca arundinacea). Two groups of 12 Angora does (initial average BW = 41.5 +/- 2.7 kg) that previously grazed a pasture of sericea lespedeza or crabgrass/tall fescue for approximately 4 mo were used. After 1 wk of adaptation to metabolism cages, gas exchange was measured for 24 h in an open-circuit respiration calorimetry system with four head boxes. Forage harvested daily from the previously grazed pastures was consumed ad libitum. Crude protein concentration was 10.3 and 13.0%, IVDMD was 64.5 and 75.3%, and the level of condensed tannins was 17.7 and 0.5% for sericea lespedeza and crabgrass/tall fescue, respectively. Dry matter intake (1.11 vs. 0.67 kg/d) and digestible DMI (estimated from IVDMD; 0.71 vs. 0.51 kg/d) were greater (P < 0.01) for sericea lespedeza than for crabgrass/tall fescue. Ruminal ammonia N (3.7 and 9.9 mg/dL; P < 0.001) and plasma urea-N concentrations (16.7 and 20.9 mg/dL; P = 0.07) were lower for sericea lespedeza than for crabgrass/tall fescue. Concentrations of individual and total VFA and the acetate-to-propionate ratio in ruminal fluid did not differ between treatments (P > 0.19). Despite higher DMI by goats fed sericea lespedeza, daily energy expenditure (409 vs. 431 kJ/kg BW(0.75)), heart rate (70 vs. 73 beats/min), and the ratio of energy expenditure to heart rate (5.82 vs. 5.94) did not differ between sericea lespedeza and crabgrass/tall fescue, respectively (P > 0.13). Methane emission expressed as both quantity per day or relative to DMI was lower (P <0.001) for sericea lespedeza than for crabgrass/tall fescue (7.4 vs. 10.6 g/d and 6.9 vs. 16.2 g/kg DMI). Substantial differences between the forages in condensed tannins concentration and methane emission by Angora goats suggest that condensed tannins decreased methane emission.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Cabras/metabolismo , Lespedeza/metabolismo , Metano/análise , Proantocianidinas/metabolismo , Amônia/análise , Ração Animal/análise , Animais , Nitrogênio da Ureia Sanguínea , Peso Corporal/fisiologia , Digitaria/metabolismo , Ingestão de Alimentos/fisiologia , Ácidos Graxos Voláteis/análise , Feminino , Festuca/metabolismo , Troca Gasosa Pulmonar/fisiologia , Rúmen/química
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