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Leaves, flowers, immature fruits and leafy flowered stems of Malva sylvestris: a comparative study of the nutraceutical potential and composition

Barros, Lillian; Carvalho, Ana Maria; Ferreira, Isabel C.F.R.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.57%
Malva sylvestris is widely used in Mediterranean and European traditional medicine and ethnoveterinary for the treatment of external and internal inflammation, as well as injuries. Moreover, its use is not only limited to therapeutic purposes; but also the species is locally regarded as a food wild herb. Considering that antioxidants and free radical scavengers can exert also an anti-inflammatory effect, the extracts of different parts of the medicinal/edible plant M. sylvestris (leaves, flowers, immature fruits and leafy flowered stems) were compared for their nutraceutical potential (antioxidant properties) and chemical composition. Particularly, mallow leaves revealed very strong antioxidant properties including radicalscavenging activity (EC50 = 0.43 mg/mL), reducing power (0.07 mg/mL) and lipid peroxidation inhibition in lipossomes (0.04 mg/mL) and brain cells homogenates (0.09 mg/mL). This part of the plant is also the richest in nutraceuticals such as powerful antioxidants (phenols, flavonoids, carotenoids, and tocopherols), unsaturated fatty acids (e.g. a-linolenic acid), and minerals measured in ash content

Decifrando raízes e caules de lianas de Sapindaceae: diversidade macroscópica e conexões vasculares; Unraveling roots and stems of Sapindaceae lianas: macroscopical diversity and vascular connections

Bastos, Carolina Lopes
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 23/03/2015 PT
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Diversos estudos de anatomia vegetal abordaram as variações cambiais frequentemente presentes nos caules de lianas de Sapindaceae, mas trabalhos que se baseiam na análise das raízes ainda são pouco frequentes na literatura. Por essa razão, a presente dissertação procura atender a dois objetivos, assim distribuídos. No primeiro capítulo, foi realizada uma análise comparada macroscópica de raízes e caules de 14 espécies lianescentes de cinco gêneros de Sapindaceae para verificar se os dois órgãos apresentam os mesmos tipos de variações cambiais e se a anatomia do xilema secundário é semelhante. No segundo capítulo, analisaram-se detalhadamente, em termos macro e microscópicos, as raízes da espécie Serjania caracasana para observar anatomicamente a configuração do xilema e floema secundários e as variações cambiais, além de verificar se existem conexões entre os cilindros vasculares periféricos neoformados e o cilindro central. Os resultados, em síntese, evidenciaram que: I. O principal tipo de variação cambial caulinar está ausente nas raízes; II. O xilema e o floema secundário das raízes amostradas são macro e microscopicamente similares aos dos caules; III. Xilema interrompido por cunhas de floema e neoformações de cilindros vasculares periféricos foram observados em raízes e caules em estágio avançado de desenvolvimento; IV. Conexões vasculares entre os cilindros neoformados e o cilindro vascular original aparecem em diversos pontos das raízes de Serjania caracasana.; A number of studies in plant anatomy have explored the cambial variants present in the stems of Sapindaceae lianas...

Anti-inflammatory, antiallodynic effects and quantitative analysis of gallic acid in spray dried powders from phyllanthus niruri leaves, stems, roots and whole plant

Couto, Angélica Garcia; Kassuya, Candida A.L.; Calixto, João Batista; Petrovick, Pedro Ros
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: application/pdf
ENG
Relevância na Pesquisa
26.88%
The anti-inflammatory and antiallodynic effects of spray dried powders starting from leaves, stems, roots, the mixture of leaves and stems, as well as the whole plant aqueous solutions of Phyllanthus niruri L., Phyllanthaceae, were assessed. Gallic acid, used as chemical marker, was quantified by HPLC in the spray dried powders. Carrageenan-induced inflammatory and allodynic responses in the mouse paw were used as pharmacological models. Quantitative and qualitative differences among chemical composition of different herb parts were observed. The oral administration of leaves or leaves plus stems spray dried powders (100 mg/kg) significantly inhibited the carrageenan-induced allodynic effect (42±5 and 54±3%, respectively). Additionally, the spray dried powders of leaves significantly reduced carrageenan-induced paw oedema (35±6%). The spray dried powders of roots, stems, or the mixture of leaves, stems and roots (100 mg/kg, p.o.) did not exhibit antiallodynic or antioedematogenic effect in the same model. In conclusion, differences in the chemical composition of spray dried powders from P. niruri are reflected in their in vivo pharmacological actions. Despite of a direct relationship of anti-inflammatory and antiallodynic effects with the gallic acid content had been observed...

Degradabilidade do capim-elefante em diferentes estágios de maturidade avaliada pelo método in vitro/gás

Campos, Fábio Prudêncio de; Lanna, Dante Pazzanese Duarte; Bose, Max Lázaro Vieira; Boin, Celso; Sarmento, Patrícia
Fonte: Universidade de São Paulo (USP), Escola Superior de Agricultura Luiz de Queiroz (ESALQ) Publicador: Universidade de São Paulo (USP), Escola Superior de Agricultura Luiz de Queiroz (ESALQ)
Tipo: Artigo de Revista Científica Formato: 217-225
POR
Relevância na Pesquisa
26.83%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); O capim-elefante (Pennisetum purpureum Schum.) é uma gramínea tropical de elevada capacidade de acumulação de matéria seca, mas seu valor nutritivo é acentuadamente influenciado pela maturidade. Considerando a natureza intrínseca da parede celular nas diferentes partes da planta, o conhecimento de suas taxas e extensões de degradação permite a determinação de qual componente e qual estágio de maturidade que afeta sua digestão. Portanto, o objetivo deste trabalho foi avaliar a degradabilidade da matéria seca (MS) do capim-elefante cv. Napier, pelo método in vitro/gás, com cortes de 45 a 105 dias a intervalos de 10 dias entre os cortes. Notou-se decréscimo na degradabilidade das frações do capim-elefante com o avanço do estágio de maturidade. Os coeficientes de regressão da degradabilidade da MS estimados pelo resíduo remanescente da digestão para folhas e hastes foram 0,51 e 0,89, respectivamente. Para degradabilidade da fibra em detergente neutro (FDN) os coeficientes de regressão para folhas e hastes foram 0,82 e 0,92, respectivamente. Na produção total de gás os coeficientes de regressão para folhas foi de 0,56 e 0,90 para hastes. em geral...

Lower Permian stems as fluvial paleocurrent indicators of the Parnaíba Basin, northern Brazil

Capretz, Robson Louiz; Rohn, Rosemarie
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 69-82
ENG
Relevância na Pesquisa
27.03%
A comprehensive biostratinomic study was carried out with abundant stems from the Lower Permian Motuca Formation of the intracratonic Parnaíba Basin, central-north Brazil. The fossils represent a rare tropical to subtropical paleofloristic record in north Gondwana. Tree ferns dominate the assemblages (mainly Tietea, secondarily Psaronius), followed by gymnosperms, sphenophytes, other ferns and rare lycophytes. They are silica-permineralized, commonly reach 4 m length (exceptionally more than 10 m), lie loosely on the ground or are embedded in the original sandstone or siltstone matrix, and attract particular attention because of their frequent parallel attitudes. Many tree fern stems present the original straight cylindrical to slightly conical forms, other are somewhat flattened, and the gymnosperm stems are usually more irregular. Measurements of stem orientations and dimensions were made in three sites approximately aligned in a W-E direction in a distance of 27.3 km at the conservation unit Tocantins Fossil Trees Natural Monument In the eastern site, rose diagrams for 54 stems indicate a relatively narrow azimuthal range to SE. These stems commonly present attached basal bulbous root mantles and thin cylindrical sandstone envelopes...

Okra seedlings production in protected environment, testing substrates and producing fruits in field

Costa,Edilson; Souza,Taynara G de; Benteo,Gleciane de L; Benett,Katiane SS; Benett,Cleiton GS
Fonte: Associação Brasileira de Horticultura Publicador: Associação Brasileira de Horticultura
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2013 EN
Relevância na Pesquisa
26.91%
The okra grows well in hot weather, finding favorable conditions for development in Brazil. We evaluated the production of okra seedlings and productivity. The experiment was conducted in the experimental area of the State University of Mato Grosso do Sul, in Aquidauana. In the seedling phase we tested substrates (100% triturated cassava stems, 75% triturated cassava stems and 25% vermiculite, 50% triturated cassava stems and 50% vermiculite, 25% triturated cassava stems and 75% vermiculite and 100% vermiculite). These substrates were placed in two protected environments (nursery with black screen, 50% of shading, and aluminized screen, 50% of shading). Each environment was considered an experiment conducted in completely randomized design with eight replications. After that we realized joint analysis. In the field, a total of 10 treatments generated from combinations of environments and substrates (2 environments x 5 substrates) were distributed in a randomized block design with four replications. The average proportions of cassava stems and vermiculite may be suitable for okra seedlings. The results of shoot and total dry phytomass indicate that the aluminized screen can be recommended for okra seedlings production when the substrate with a 1:1 ratio is used. Seedlings grown on higher percentages of vermiculite anticipate production...

Anti-inflammatory, antiallodynic effects and quantitative analysis of gallic acid in spray dried powders from Phyllanthus niruri leaves, stems, roots and whole plant

Couto,Angélica G.; Kassuya,Candida A. L.; Calixto,João B.; Petrovick,P. R.
Fonte: Sociedade Brasileira de Farmacognosia Publicador: Sociedade Brasileira de Farmacognosia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2013 EN
Relevância na Pesquisa
26.88%
The anti-inflammatory and antiallodynic effects of spray dried powders starting from leaves, stems, roots, the mixture of leaves and stems, as well as the whole plant aqueous solutions of Phyllanthus niruri L., Phyllanthaceae, were assessed. Gallic acid, used as chemical marker, was quantified by HPLC in the spray dried powders. Carrageenan-induced inflammatory and allodynic responses in the mouse paw were used as pharmacological models. Quantitative and qualitative differences among chemical composition of different herb parts were observed. The oral administration of leaves or leaves plus stems spray dried powders (100 mg/kg) significantly inhibited the carrageenan-induced allodynic effect (42±5 and 54±3%, respectively). Additionally, the spray dried powders of leaves significantly reduced carrageenan-induced paw oedema (35±6%). The spray dried powders of roots, stems, or the mixture of leaves, stems and roots (100 mg/kg, p.o.) did not exhibit antiallodynic or antioedematogenic effect in the same model. In conclusion, differences in the chemical composition of spray dried powders from P. niruri are reflected in their in vivo pharmacological actions. Despite of a direct relationship of anti-inflammatory and antiallodynic effects with the gallic acid content had been observed...

Disruption of the Actin Cytoskeleton Results in the Promotion of Gravitropism in Inflorescence Stems and Hypocotyls of Arabidopsis1

Yamamoto, Kazuyoshi; Kiss, John Z.
Fonte: American Society of Plant Biologists Publicador: American Society of Plant Biologists
Tipo: Artigo de Revista Científica
Publicado em /02/2002 EN
Relevância na Pesquisa
26.88%
The actin cytoskeleton is hypothesized to play a major role in gravity perception and transduction mechanisms in roots of plants. To determine whether actin microfilaments (MFs) are involved in these processes in stem-like organs, we studied gravitropism in Arabidopsis inflorescence stems and hypocotyls. Localization studies using Alexa Fluor-phalloidin in conjugation with confocal microscopy demonstrated a longitudinally and transversely oriented actin MF network in endodermal cells of stems and hypocotyls. Latrunculin B (Lat-B) treatment of hypocotyls caused depolymerization of actin MFs in endodermal cells and a significant reduction of hypocotyl growth rates. Actin MFs in Lat-B-treated inflorescence stems also were disrupted, but growth rates were not affected. Despite disruption of the actin cytoskeleton in these two organs, Lat-B-treated stems and hypocotyls exhibited a promotion of gravitropic curvature in response to reorientation. In contrast, Lat-B reduced gravitropic curvature in roots but also reduced the growth rate. Thus, in contrast to prevailing hypotheses, our results suggest that actin MFs are not a necessary component of gravitropism in inflorescence stems and hypocotyls. Furthermore, this is the first study to demonstrate a prominent actin MF network in endodermal cells in the putative gravity-perceiving cells in stems.

Fructan 1-Exohydrolases. β-(2,1)-Trimmers during Graminan Biosynthesis in Stems of Wheat? Purification, Characterization, Mass Mapping, and Cloning of Two Fructan 1-Exohydrolase Isoforms1[w]

Van den Ende, Wim; Clerens, Stefan; Vergauwen, Rudy; Van Riet, Liesbet; Van Laere, André; Yoshida, Midori; Kawakami, Akira
Fonte: American Society of Plant Biologists Publicador: American Society of Plant Biologists
Tipo: Artigo de Revista Científica
Publicado em /02/2003 EN
Relevância na Pesquisa
26.83%
Graminan-type fructans are temporarily stored in wheat (Triticum aestivum) stems. Two phases can be distinguished: a phase of fructan biosynthesis (green stems) followed by a breakdown phase (stems turning yellow). So far, no plant fructan exohydrolase enzymes have been cloned from a monocotyledonous species. Here, we report on the cloning, purification, and characterization of two fructan 1-exohydrolase cDNAs (1-FEH w1 and w2) from winter wheat stems. Similar to dicot plant 1-FEHs, they are derived from a special group within the cell wall-type invertases characterized by their low isoelectric points. The corresponding isoenzymes were purified to electrophoretic homogeneity, and their mass spectra were determined by quadrupole-time-of-flight mass spectrometry. Characterization of the purified enzymes revealed that inulin-type fructans [β-(2,1)] are much better substrates than levan-type fructans [β-(2,6)]. Although both enzymes are highly identical (98% identity), they showed different substrate specificity toward branched wheat stem fructans. Although 1-FEH activities were found to be considerably higher during the fructan breakdown phase, it was possible to purify substantial amounts of 1-FEH w2 from young, fructan biosynthesizing wheat stems...

Floral Activity in Solutions of Deoxyribonucleic Acid Extracted from Tobacco Stems 1

Wardell, William L.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /06/1976 EN
Relevância na Pesquisa
26.91%
For Nicotiana tabacum cv. Wis. 38 plants, the capabilities of solutions containing DNA, extracted from either homogenates of stems in a floral state or nuclei of stems in a vegetative state, to effect flowering of vegetative plants have been studied. Previous work indicates that the DNA from homogenates of stems in a floral state is mainly nuclear. If DNA solutions are supplied to axillary buds of vegetative plants and if the axillary buds are defoliated every 4th day for 12 days, the buds supplied a solution of DNA from stems in a floral state initiate flowers under noninductive conditions, and the buds supplied a solution of DNA from stems in a vegetative state remain vegetative. Heating and rapidly cooling a solution of DNA from stems in a floral state enhances its floral activity. Heating and cooling a DNA solution also results in novel flowers showing up in many treated plants. Novel flowers are more striking in the offspring than in the parents. The capabilities of heated-cooled DNA solution to initiate flowers in noninductive conditions and to cause novel flowers are eliminated completely by treating (before heating and cooling) the DNA solution with deoxyribonuclease. Heated-cooled solutions of DNA extracted from nuclei of either vegetative stems or vegetative leaves contain no floral activity.

Improving the prediction of RNA secondary structure by detecting and assessing conserved stems

Fang, Xiaoyong; Luo, Zhigang; Yuan, Bo; Wang, Jinhua
Fonte: Biomedical Informatics Publishing Group Publicador: Biomedical Informatics Publishing Group
Tipo: Artigo de Revista Científica
Publicado em 30/12/2007 EN
Relevância na Pesquisa
26.83%
The prediction of RNA secondary structure can be facilitated by incorporating with comparative analysis of homologous sequences. However, most of existing comparative methods are vulnerable to alignment errors and thus are of low accuracy in practical application. Here we improve the prediction of RNA secondary structure by detecting and assessing conserved stems shared by all sequences in the alignment. Our method can be summarized by: 1) we detect possible stems in single RNA sequence using the so-called position matrix with which some possibly paired positions can be uncovered; 2) we detect conserved stems across multiple RNA sequences by multiplying the position matrices; 3) we assess the conserved stems using the Signal-to-Noise; 4) we compute the optimized secondary structure by incorporating the so-called reliable conserved stems with predictions by RNAalifold program. We tested our method on data sets of RNA alignments with known secondary structures. The accuracy, measured as sensitivity and specificity, of our method is greater than predictions by RNAalifold.

Minimum 10-year Survival of Kerboull Cemented Stems According to Surface Finish

Hamadouche, Moussa; Baqué, François; Lefevre, Nicolas; Kerboull, Marcel
Fonte: Springer-Verlag Publicador: Springer-Verlag
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
26.88%
The optimal surface finish for a cemented THA stem is still debated. We hypothesized surface finish would influence survival of Kerboull cemented hip arthroplasties and a matte finish would have lower survival. We reviewed survival of 433 total hip arthroplasties in 395 patients: 284 consecutive patients (310 hips) were enrolled in a prospective, randomized study of polished (165 hips) or matte finish stems (145 hips) and compared to a historical series of satin stems (123 hips) in 111 patients. The satin and matte finish implants had similar geometry but the polished was quadrangular rather than oval. Finish roughnesses were: polished (radius, 0.04 μm), satin (radius, 0.9 μm), and matte (radius, 1.7 μm). The mean age of the patients at the time of the index arthroplasty was 63.6 years. The survival rate at 13 years, using radiographic loosening as the end point, was 97.3% ± 2.6% for polished stems, 97.1% ± 2.1% for satin stems, and 78.9% ± 5.8% for matte stems. The data suggest survival of Kerboull stems was higher with a polished or satin surface finish than with a matte finish.

Manejo pós-colheita de Alpinia purpurata (Vieill) K. Schum (Zingiberaceae)

Silva, Antonio Tarciso Ciríaco da
Fonte: Universidade Federal de Alagoas; BR; Agronomia; Produção vegetal; Proteção de plantas; Programa de Pós-Graduação em Agronomia; UFAL Publicador: Universidade Federal de Alagoas; BR; Agronomia; Produção vegetal; Proteção de plantas; Programa de Pós-Graduação em Agronomia; UFAL
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
27.03%
The growth of ornamental plant market in Brazil is remarkable nowadays with strong participation of Northeast region, particularly in Alagoas State on the commercialization of tropical flowers. Taking into account this economic aspect, it is of great importance for the productive chain of ornamental species the study of aspects of post harvest activities. Alpinia purpurata (Viell) K. Schum (Zingiberaceae) which occupies the second place in economic importance amongst tropical flowers. It is the main flower for growing and harvesting. The main objective of this research programme is to study the different aspects of Alpinia post-harvesting: (1) time of harvesting and cut of the basis of the stems, and (2) the use of solutions of pulsing ; and/or maintenance of the floral stem by using: (2.1.) biocide compounds and pH of the solution; (2.2) carbohydrates and carbohydrates plus biocides; (2.3) anti-ethylene compounds and antiethylene compounds plus carbohydrates; (2.4) elements as calcium and silicon; and (2.5) senescence retarding growth regulators. It was evaluated the influence of these factors in the water relations, quality and longevity of the stems. Six experiments were carried out in the laboratory (CECA) of the Federal University of Alagoas. In the first experiment...

The influence of seeding density and environmental factors on grain quality of main stems and tillers of wheat in South Australia

Tonkin, Rebecca
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado Formato: 2096097 bytes; 323415 bytes; application/pdf; application/pdf
Publicado em //2004 EN
Relevância na Pesquisa
26.91%
Prime Hard wheat, a high protein hard wheat classification of the Australian Wheat Board, has traditionally been grown in Queensland and the northern areas of New South Wales. Recently there have been moves to extend this area into the more southern regions of the wheat belt, to expand production of this grain and for greater reliability of supply. The emphasis of this thesis is on the opportunities and constraints to Prime Hard wheat production in South Australia. The environmental factors affecting wheat crops in South Australia are different to those in the traditional Prime Hard producing areas, with heat and moisture stress likely to be the most important climatic influences. Management practices such as the recent trends towards higher seeding densities could also be important (influencing main stem and tiller ratios). An experiment using controlled temperature and moisture conditions showed that main stems and tillers differed in their responses to post-anthesis heat and drought. A field experiment with moisture stress as the only treatment also showed differences in harvest parameters and grain quality between main stems and tillers. Grain produced from field plots at different plant densities showed significant differences in a number of quality measurements...

Exeter short stems compared with standard length exeter stems : experience from the Australian orthopaedic association national joint replacement registry

Choy, G.; Roe, J.; Whitehouse, S.; Cashman, K.; Crawford, R.
Fonte: Churchill Livingstone Inc Medical Publishers Publicador: Churchill Livingstone Inc Medical Publishers
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
Relevância na Pesquisa
26.88%
The standard Exeter stem has a length of 150 mm with offsets 37.5 to 56 mm. Shorter stems of lengths 95, 115 and 125 mm with offsets 35.5 mm or less are available for patients with smaller femurs. Concern has been raised regarding the behavior of the smaller implants. This paper analyzed data from the Australian Orthopaedic Association National Joint Replacement Registry comparing survivorship of stems of offset 35.5 mm or less with the standard stems of 37.5 mm offset or greater. At 7 years, there was no significant difference in the cumulative percent revision rate in the short stems (3.4%, 95% CI 2.4-4.8%) compared with the standard length stems (3.5%, 95% CI 3.3-3.8%) despite its use in a greater proportion of potentially more difficult developmental dysplasia of the hip cases.; Godwin G.H. Choy, John A. Roe, Sarah L. Whitehouse, Kara S. Cashman and Ross W. Crawford

Chemical characterization and bioactive properties of Prunus avium L.: The widely studied fruits and the unexplored stems

Bastos, Claudete; Barros, Lillian; Dueñas, Montserrat; Calhelha, Ricardo C.; Queiroz, Maria João R.P.; Santos-Buelga, Celestino; Ferreira, Isabel C.F.R.
Fonte: Instituto Politécnico de Bragança Publicador: Instituto Politécnico de Bragança
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.83%
The aim of this study was to characterize sweet cherry regarding nutritional composition of the fruits, and individual phytochemicals and bioactive properties of fruits and stems. The chromatographic profiles in sugars, organic acids, fatty acids, tocopherols and phenolic compounds were established. All the preparations (extracts, infusions and decoctions) obtained using stems revealed higher antioxidant potential than the fruits extract, which is certainly related with its higher phenolic compounds (phenolic acids and flavonoids) concentration. The fruits extract was the only one showing antitumor potential, revealing selectivity against HCT-15 (colon carcinoma) (GI50~74 μg/mL). This could be related with anthocyanins that were only found in fruits and not in stems. None of the preparations have shown hepatotoxicity against normal primary cells. Overall, this study reports innovative results regarding chemical and bioactive properties of sweet cherry stems, and confirmed the nutritional and antioxidant characteristics of their fruits.; The authors are grateful to Foundation for Science and Technology (FCT, Portugal) for financial support to the research centre CIMO (strategic project PEst-OE/AGR/UI0690/2011) and L. Barros researcher contract under “Programa Compromisso com Ciência – 2008”.

Biomass production and essential oil yield from leaves, fine stems and resprouts using pruning the crown of Aniba canelilla (H.B.K.) (Lauraceae) in the Central Amazon

Manhães,Adriana Pellegrini; Veiga-Júnior,Valdir Florêncio da; Wiedemann,Larissa Silveira Moreira; Fernandes,Karenn Silveira; Sampaio,Paulo de Tarso Barbosa
Fonte: Instituto Nacional de Pesquisas da Amazônia Publicador: Instituto Nacional de Pesquisas da Amazônia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2012 EN
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26.88%
Aniba canelilla (H.B.K.) Mez. is a tree species from Amazon that produces essential oil. The oil extraction from its leaves and stems can be an alternative way to avoid the tree cutting for production of essential oil. The aim of this study was to analyse factors that may influence the essential oil production and the biomass of resprouts after pruning the leaves and stems of A. canelilla trees. The tree crowns were pruned in the wet season and after nine months the leaves and stems of the remaining crown and the resprouts were collected, in the dry season. The results showed that the essential oil yield and chemical composition differed among the stems, leaves and resprouts. The stems' essential oil production differed between the seasons and had a higher production in the resprouting stems than the old stems of the remaining crown. The production of essential oil and leaf biomass of resprouts were differently related to the canopy openness, indicating that light increases the production of the essential oil and decreases the biomass of resprouting leaves. This study revealed that plant organs differ in their essential oil production and that the canopy openness must be taken into account when pruning the A. canelilla tree crown in order to achieve higher oil productivity.

Can children's spelling of schwa vowels in stems be improved?

Rosa,João; Nunes,Terezinha
Fonte: Setor de Educação da Universidade Federal do Paraná Publicador: Setor de Educação da Universidade Federal do Paraná
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2010 EN
Relevância na Pesquisa
36.69%
Children in the early grades of primary school do not seem to have much awareness of morphemes. In this study, a priming paradigm was used to try to detect early signs of morphological representation of stems through a spelling task presented to Portuguese children (N= 396; age range 6 to 9 years). Primes shared the stem with the targets and contained well-articulated, stressed vowels; the stems of the target words contained non-stressed schwa vowels, which typically result in spelling difficulties. If priming proved effective, the well-articulated vowels in the prime should lead to improvement in the spelling of the schwa vowels in the targets. Primes were presented in two conditions: in only-oral or in oral-plus-written form. Effectiveness of priming was assessed by comparison with a no-priming condition. There was a significant interaction between priming effects and grade. No priming effects were detected in 6- and 7-year-old children; oral-plus-written priming produced higher rates of correct vowel spelling for 8- and 9-year-olds; only-oral priming was effective in improving the vowel spelling of 9-year-olds. Thus the older children used morphological information under priming conditions but there is no evidence to suggest that younger children did so.

SIMULTANEOUS SACCHARIFICATION AND FERMENTATION OF CASSAVA STEMS

CASTAÑO PELÁEZ,HADER; REALES ALFARO,JUAN; ZAPATA MONTOYA,JOSÉ
Fonte: DYNA Publicador: DYNA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2013 EN
Relevância na Pesquisa
36.88%
This research evaluates the effects of the inoculum size and enzymatic activity on the concentration of ethanol obtained through the simultaneous saccharification and fermentation of alkali-pretreated cassava stems. Other goals for this study include the determination and validation of the optimal conditions for and the evaluation of the process of ethanol production in a bioreactor. Alkaline-pretreated cassava stems were used as the substrate in a solid to liquid ratio of 1:10; the enzymatic complex Accellerase 1500 and the yeast Ethanol Red were evaluated at two levels at a temperature of 38° C and a pH of 4.0 in an Erlenmeyer flask. The following were evaluated as process controls: simultaneous saccharification and fermentation of non-pretreated stems and separate saccharification and fermentation of pretreated stems. A regression analysis was conducted, and the resulting model was maximized using genetic algorithms. At the optimal conditions identified in an Erlenmeyer flask, the production of ethanol in a 5-liter bioreactor was subsequently evaluated. An experimental concentration of ethanol of 1.88±0.04% v/v (1.99% v/v simulated optimum) was obtained using an inoculum concentration of 1.59 g/L and an enzyme concentration of 13.3 FPU/g. This value was approximately four times the quantity of ethanol produced without pretreatment or by the separate saccharification and fermentation of pretreated cassava stems. The evaluation of the process in the bioreactor yielded an ethanol concentration 20% less than that reached in the Erlenmeyer flask.

Optimization of Extraction Conditions for Flavonoids of Physalis alkekengi var. franchetii Stems by Response Surface Methodology and Inhibition of Acetylcholinesterase Activity

Xue-gui,Liu; Fu-yu,Jiang; Gao,Pin-yi; Jin,Mei; Yang,Di; Nian,Zhong-feng; Zhang,Zhen-xue
Fonte: Sociedad Química de México A.C. Publicador: Sociedad Química de México A.C.
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2015 EN
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The microwave-assisted extraction conditions of flavonoids in Physalis alkekengi. var. franchetii stems were optimized using a L3³ Box-Behnken Design. The optimized extraction conditions were determined as follows: 60% for the ethanol concentration, 12.4 for the liquid-to-solid ratio, and 531.4 W for the microwave power, respectively. The yield of the extract obtained under the optimized conditions was 3.85 mg g-1 which was close to the predicted value. In addition, the extract exhibited potent acetylcholinesterase inhibitory activity, with the IC50 value of 11.61 μg mL-1 and a maximal inhibition ratio 89.81%. Both the yield and activity were better than reflux extraction.