99 resultados para rhizomes


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The present work aims to characterize and quantify the phenolic composition and to evaluate the antioxidant activity of Glycyrrhiza glabra L. (commonly known as licorice) rhizomes and roots. The antioxidant potential of its methanol/water extract could be related with flavones (mainly apigenin derivatives), flavanones (mainly liquirintin derivatives), a methylated isoflavone and a chalcone, identified in the extract. Lipid peroxidation inhibition was the most pronounced antioxidant effect (EC50=0.24±0.01 µg/mL and 22.74±2.42 µg/mL in TBARS and -carotene/linoleate assays, respectively), followed by free radicals scavenging activity (EC50=111.54±6.04 µg/mL) and, finally, reducing power (EC50=128.63±0.21 µg/mL). In this sense, licorice extract could be used as a source of antioxidants for pharmaceutical, cosmetic and/or food industries.

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ABSTRACT: Increasing restrictions on the use of artificial pigments in the food industry, imposed by the international market, have increased the importance of raw materials containing natural pigments. Of those natural substances with potential applications turmeric rhizomes (Curcuma longa L), are one of the most important natural sources of yellow coloring. Three different pigments (curcumin, desmetoxycurcumin, and bis-desmetoxycurcumin) constitute the curcuminoids. These pigments are largely used in the food industry as substitutes for synthetic dyes like tartrazin. Extraction of curcuminoids from tumeric rhizomes with supercritical CO2 can be applied as an alternative method to obtain curcuminoids, as natural pigments are in general unstable, and hence degrade when submitted to extraction with organic solvents at high temperatures. Extraction experiments were carried out in a supercritical extraction pilot plant at pressures between 25 and 30 MPa and a temperature of 318 K. The influence of drying pretreatment on extraction yield was evaluated by analyzing the mass transfer kinetics and the content of curcuminoids in the extracts during the course of extraction. The chemical identification of curcuminoids in both the extract and the residual solid was performed by spectrophotometry. Mass transfer within the solid matrix was described by a linear first-order desorption model, while that in the gas phase was described by a convective mass transfer model. Experimental results showed that the concentration profile for curcuminoids during the supercritical extraction process was higher when the turmeric rhizomes were submitted to a drying pretreatment at 343 K.

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Three new steroid saponins (3beta,25R)-spirost-5-en-3-yl 6-deoxy-alpha-L-mannopyranosyl-(1-->2)-[beta-D-glucopyranosyl-(1-->4)-6-deoxy-alpha-L-mannopyranosyl-(1-->3)]-beta-D-glucopyranoside (1), (3beta,22R,25R)-26-(beta-D-glucopyranosyloxy)-22-hydroxyfurost-5-en-3-yl 6-deoxy-alpha-L-mannopyranosyl-(1-->2)-[6-deoxy-alpha-L-mannopyranosyl-(1-->3)]-beta-D-glucopyranoside (3), and (3beta,22R,25R)-26-(beta-D-glucopyranosyloxy)-22-hydroxyfurost-5-en-3-yl 6-deoxy-alpha-L-mannopyranosyl-(1-->2)-[beta-D-glucopyranosyl-(1-->4)-6-deoxy-alpha-L-mannopyranosyl-(1-->3)]-beta-D-glucopyranoside (5), as well as the new pregnane glycoside (3beta,16beta)-3-{[6-deoxy-alpha-L-mannopyranosyl-(1-->2)-[6-deoxy-alpha-L-mannopyranosyl-(1-->3)]-beta-D-glucopyranosyl]oxy}-20-oxopregn-5-en-16-yl (4R)-5-(beta-D-glucopyranosyloxy)-4-methylpentanoate (6), were isolated from the rhizomes of Tacca integrifolia together with two known (25R) configurated steroid saponins (3beta,25R)-spirost-5-en-3-yl 6-deoxy-alpha-L-mannopyranosyl-(1-->2)-[6-deoxy-alpha-L-mannopyranosyl-(1-->3)]-beta-D-glucopyranoside (2) and (3beta,22R,25R)-26-(beta-D-glucopyranosyloxy)-22-methoxyfurost-5-en-3-yl 6-deoxy-alpha-L-mannopyranosyl-(1-->2)-[6-deoxy-alpha-L-mannopyranosyl-(1-->3)]-beta-D-glucopyranoside (4). The cytotoxic activity of the isolated compounds was evaluated in HeLa cells and showed the highest cytotoxicity value for compound 2 with an IC(50) of 1.2+/-0.4 muM. Intriguingly, while compounds 1-5 exhibited similar cytotoxic properties between 1.2+/-0.4 (2) and 4.0+/-0.6 muM (5), only compound 2 showed a significant microtubule-stabilizing activity in vitro.

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Gamma irradiation has been widely used as a breeding technique to obtain new cultivars in ornamental species such as Alstroemeria, where several cultivars have been obtained through rhizome radiation. The optimum dosage for an appropriate induction of mutation must be considered for breeding purposes and it depends mainly on plant susceptibility. Thus in this study in vitro cultured rhizomes of Alstroemeria aurea were irradiated with a gamma source using different dosages to evaluate the direct effect produced. Damage and number of rhizome sprouting were observed and recorded during 61 days after irradiation. At the end of this period, rhizomes were weighted and mortality was evaluated. Both mortality and weight increased depending on dosage. All irradiated rhizomes showed early sprouting in comparison with control (0 Gy) and no significant difference in final number of shoots after 61 days among irradiated treatments was observed. Bleaching and necrosis was observed in all irradiated rhizomes and was more evident at higher doses. LD50 was established at about 40 Gy and the optimum dosage to induce mutation was suggested between 2.5 and 5 Gy, when the growth was reduced in 50%, and probably this dosage could be used for breeding purposes.

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Foram analisados os rizomas de Bulbostylis paradoxa Ness, Cyperus giganteus Vahl, C. odoratus L., Fuirena umbellata Rottb. e Hypolytrum schraderianum Ness. O corpo primário é resultante da atividade dos meristemas apicais e do meristema de espessamento primário (MEP). Também ocorre crescimento em espessura, que é decorrente da atividade do meristema de espessamento secundário (MES). O procâmbio e o MEP originam feixes colaterais em H. schraderianum e feixes anfivasais nas demais espécies. Entretanto, todos os feixes que têm protofloema e protoxilema são de origem procambial. O MES produz floema e xilema constituindo um tecido vascular único. Elementos de vaso foram encontrados na maioria dos caules em estrutura primária e secundária, com exceção de H. schraderianum que, na estrutura secundária, contém apenas traqueídes, informação que respalda a ocorrência de crescimento secundário nas Cyperaceae. Os elementos de vaso apresentam grande variação morfológica; em estrutura primária, geralmente são mais alongados, com apêndices. Os elementos de vaso do crescimento secundário são relativamente mais curtos, apresentam apêndices e ramificações.

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Cyperaceae are usually perennial, with underground stems mainly rhizomatous, however, other stem types may also occur, such as corms and tubers. The underground stems of five Cyperaceae species were examined. Cyperus rotundus and Fuirena umbellata have plagiotropic rhizomes, while C. esculentus, C. odoratus, Hypolytrum schraderianum and Bulbostylis paradoxa have orthotropic rhizomes. Corms occur in C. rotundus and C. esculentus, and stolons in C. esculentus. The primary body originates from the activity of the apical meristem and later, from the primary thickening meristem (PTM). Secondary growth results from secondary thickening meristem (STM) activity, and occurs in rhizomes of H. schraderianum, B. paradoxa, C. odotarus and F. umbellata. The procambium and the PTM give rise to collateral bundles in H. schraderianum, and amphivasal bundles in the remaining species. The STM gives rise to the vascular system with the associated phloem and xylem. According to our results, the concept of stem type in Cyperaceae depends on external morphology, function, life phase, activity of the thickening meristems and the relative amount of parenchyma.

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Turmeric (Curcuma longa) is a triploid, vegetatively propagated crop introduced early during the colonization of Brazil. Turmeric rhizomes are ground into a powder used as a natural dye in the food industry, although recent research suggests a greater potential for the development of drugs and cosmetics. In Brazil, little is known about the genetic variability available for crop improvement. We examined the genetic diversity among turmeric accessions from a Brazilian germplasm collection comprising 39 accessions collected from the States of Goias, Mato Grosso do Sul, Minas Gerais, Sao Paulo, and Para. For comparison, 18 additional genotypes were analyzed, including samples from India and Puerto Rico. Total DNA was extracted from lyophilized leaf tissue and genetic analysis was performed using 17 microsatellite markers (single-sequence repeats). Shannon-Weiner indexes ranged from 0.017 (Minas Gerais) to 0.316 (Sao Paulo). Analyses of molecular variance (AMOVA) demonstrated major differences between countries (63.4%) and that most of the genetic diversity in Brazil is found within states (75.3%). Genotypes from Sao Paulo State were the most divergent and potentially useful for crop improvement. Structure analysis indicated two main groups of accessions. These results can help target future collecting efforts for introduction of new materials needed to develop more productive and better adapted cultivars.

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Underground systems of Asteraceac species from the Brazilian Cerrado. The aim or this study was to describe the underground systems structure, the origin of the shoot buds, and to identify the storage reserve of seven Asteraceae species in order to understand the adaptive strategies of these species in burned Cerrado areas and their higher frequency in the floristic Surveys for herbaceous and undershrub layers of this biome. The subterranean systems types-diffuse underground system, rhizophore, tuberous roots, and xylopodium-varied among the studied species, but all of them have high shoot bud-forming potential. Fructans of the inulin type were detected as storage substances. The presence of these characteristics on the underground systems Could explain the frequency of these species in the floristic surveys from the Brazilian Cerrado, in which Fire and seasonal drought are frequent. It is possible that the belowground bud banks in the Cerrado biome are as important as demonstrated in North American prairies where fire is also frequent. However, in the Cerrado, as demonstrated here, there are types of underground systems other than rhizomes that are usually described in the prairie. Understanding the anatomical features of these plants is one of the steps to appropriate conservation management of these species in the Cerrado.

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Colleters are widely occurring in eudicots showing relevant taxonomic importance in several families. Nevertheless, there are few records in monocots, restricted to only one description of these glands in Orchidaceae. The genus Oncidium is polyphyletic, currently the subject of taxonomic studies. In this context, the secretory structures can be an important diagnostic character that may help in the delineation of this group. O. flexuosum Sims presents colleters in vegetative - leaf primordium of protocorms, apical and axillary buds in the mature rhizomes - and reproductive organs - at the base of bracts, bracteoles and sepals. All the colleters observed are finger-like trichomes, composed of two uniseriated cells, where the apical one is elongated and possesses dense cytoplasm. The exsudate accumulates in a subcuticular space. causing displacement of the cuticle. Histochemical tests indicate the presence of mucilage in association with lipophilic and proteinic compounds inside the secretory cell. Secretion is abundant, hyaline and slightly viscous. The localization of the trichomes and their exsudate indicate the involvement of these colleters with the protection of meristematic regions in vegetative and reproductive organs. These results can be useful in the taxonomy of the genus Oncidium and for future studies about colleters in monocots. (C) 2010 Elsevier GmbH. All rights reserved.

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P>Curcuma longa L. is a sterile, triploid, vegetatively-propagated crop cultivated mainly in Southeast Asia. When dried rhizomes are ground, the resulting yellow powder is used by the food industry as a natural food dye. Moreover, many pharmacological compounds have broadened the commercial application of the crop. However, conventional breeding is difficult and hence, improvement has been limited to germplasm selection. To better utilize the germplasm collections and facilitate genotype selection, a total of 17 polymorphic microsatellite loci were developed using a CT/GT/CTT enriched genomic library. All microsatellites resulted in amplified PCR products, showing a banding pattern of 2-11 polymorphic bands per locus, enabling genotype discrimination. These results can be used in further studies aimed at characterizing C. longa genetic resource collections and also to improve breeding strategies.

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The rhizomes of Dryopteris species have popularly been used as vermifuge in flatworm infections. The aim of this work was to evaluate the in vitro schistosomicidal activity of some phloroglucinol compounds, obtained from the rhizomes of Dryopteris species, against Schistosoma mansoni adult worms. All worm pairs were dead after 24 h of incubation with aspidin 25 to 100 mu M (1), flavaspidic acid 50 and 100 mu M (2), methylene-bis-aspidinol 100 mu M (3), and desaspidin 25 to 100 mu M (4). Worms incubated with 1 (25 to 100 mu M) and 2 (50 to 100 mu M) showed decrease motor activity with tegumental alterations, while 3 (100 mu M) and 4 (10 to 100 mu M) showed decrease motor activity without tegumental alterations. Desaspidinol (5) and filicinic acid (6), at the tested concentrations (10 to 100 mu M), did not show activity against adult worms of S. mansoni. Praziquantel (10 mu M), used as positive control, caused death of the parasites and tegumental alterations without separation of worms. In the groups treated with 100 A mu M of compounds 1-4, the viability of the adult worms was similar to the positive control group, in which the worms were dead. Also, both the egg productions and the development of eggs produced by the adult worms were inhibited by the incubation with compounds 1-4 (10 and 100 mu M) in comparison with the negative control (RPMI 1640 medium). It is suggested that the in vitro schistosomicidal effects of phloroglucinols derivatives 1, 2, 3, and 4 may be related to the inhibition of oxidative phosphorylation pathway in S. mansoni. The present results confirmed the traditional indications of rhizomes from Dryopteris species, which possess phloroglucinol compounds, in the treatment of tapeworm infections.

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A tese afirma a vida por meio das biopotências que se manifestam em movimentações invisíveis aos olhos acostumados a permitir o ver, o julgar e o falar. Foca o tempo presente, na comunicação em redes, traz em si a potência de reatar a multidão, com a capacidade de sondar possibilidades mostrando o que antes parecia opaco e impossível. Perambular é ligar nas redes quentes de um bairro com/no/do território ao privilegiar o movimento, o processo, sempre caminhando pelas vias e conexões abertas, aposta estética-ética-política nos paradoxos sem superação e não hierarquizados. Toma como método de pesquisa-intervenção elementos de uma cartografia de movimentos e devires, traçando um perambular rizomático em que são problematizados a constituição do problema de pesquisa, que considera a construção do conhecimento diversificada, descentralizada e horizontalizada. Problematiza as práticas discursivas de si em suas relações com a biopolítica, a governabilidade e a biopolítica das populações. O que está(rá) rolando nesse bairro, no que foi chamado de criança, adolescente, escola, compor para que as coisas apareçam, junto com outros que vivem a loucura em duplas e trios. A tese é a possibilidade da existência de uma educação menor na periferia para as populações marginalizadas, muçulmanizadas. Educação menor, da sala de aula, do bairro, do cotidiano de professores, familiares e alunos. Educação que permite revolucionários, na medida em que alguma revolução ainda faz sentido na educação nesses dias. A educação menor constitui-se, assim, num empreendimento de militância, de professores militantes. Plano das afecções em que não há unidades, apenas intensidade. A tese fala do processo, de como reproduzir, ou não, os modos de subjetividade dominante, não se trata de medidas - "menor" ou "pequeno". Nesse sentido, é preciso considerar os efeitos de produção de subjetividade e a incorporação dos fatos à própria vida. A tese analisa movimentos instituintes buscando reconhecê-los em sua natureza contestatória e transgressora e ter conhecimento de como se organiza na escola e muito além dela. Discutindo a produtividade dessa coreografia do perambular, esboçamos movimentos que denominamos: estradas que levam a nada, além muro

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23rd ISHC Congress will be held in Glasgow, Scotland from July 31 August 4, 2011.

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Introduction In this study, we used dichloromethane (DCM) and methanol (MeOH) extracts of the Zingiber zerumbet rhizome to evaluate brine shrimp lethality and larvicidal activity on Aedes aegypti and Anopheles nuneztovari mosquitoes. Methods Bioassays were performed by exposing third-instar larvae of each mosquito species to the DCM or MeOH extracts. Results Probit analysis with DCM and MeOH extracts demonstrated efficient larvicidal activity against A. aegypti and A. nuneztovari larvae. Conclusions The DCM and MeOH extracts showed higher activity against A. nuneztovari larvae than against A. aegypti larvae, suggesting that the extracts have species-specific activity.

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Research was conducted to investigate the potential for ecologically engineering a sustainable wetland ecosystem over pyritic mine tailings to prevent the generation of acid mine drainage. Ecological engineering is technology with the primary goal being the creation of self-sustainable ecological systems. Work involved the design and construction of a pilot-scale wetland system comprising three wetland cells, each covering 100 m2. Approximately forty tonnes of pyritic mine tailings were deposited on the base of the first cell above a synthetic liner, covered with peat, flooded and planted with emergent wetland macrophytes Typha latifolia, Phragmites australis, and Juncus effusus. The second cell was constructed as a conventional free water surface wetland, planted identically, and used as a reference wetland/experimental control. Wetland monitoring to determine long-term sustainability focused on indicators of ecosystem health including ecological, hydrological, physico-chemical, geochemical, and biotic metrics. An integrated assessment was conducted that involved field ecology in addition to ecological risk assessment. The objective of the field ecology study was to use vegetative parameters as ecological indicators for documenting wetlands success or degradation. The goal of the risk assessment was to determine if heavy-metal contamination of the wetland sediments occurred through metal mobilisation from the underlying tailings, and to evaluate if subsequent water column chemistry and biotic metal concentrations were significantly correlated with adverse wetland ecosystem impacts. Data were used to assess heavy metal bioavailability within the system as a function of metal speciation in the wetland sediments. Results indicate hydrology is the most important variable in the design and establishment of the tailings wetland and suggest a wetland cover is an ecologically viable alternative for pyritic tailings which are feasible to flood. Ecological data indicate that in terms of species richness and diversity, the tailings-wetland was exhibiting the ecological characteristics of natural wetlands within two years. Ata indicate that pH and conductivity in the tailings-wetland were not adversely impacted by the acid-generating potential or sulphate concentration of the tailings substrate and its porewater. Similarly, no enhanced seasonal impacts from sulphate or metals in the water column, nor adverse impacts on the final water quality of the outflows, were detected. Mean total metal concentrations in the sediments of the tailings-wetland indicate no significant adverse mobilisation of metals into the peat substrate from the tailings. Correlation analyses indicate a general increase in sediment metal concentration in this wetland with increasing water depth and pH, and a corresponding decrease in the metal concentrations of the water column. Sediment extractions also showed enrichment of Cd, Fe, Pb and Zn in the oxidisable fraction (including sulphides and organic matter) of the tailings-wetland sediments. These data suggest that adsorption and coprecipitation of metals is occurring from the water column of the tailings wetland with organic material at increasing depths under reducing conditions. The long-term control of metal bioavailability in the tailings wetland will likely be related to the presence and continual build-up of organic carbon binding sites in the developing wetland above the tailings. Metal speciation including free-metal ion concentration and the impact of physico-chemical parameters particularly pH and organic matter, were investigated to assess ecotoxicological risk. Results indicate that potentially bioavailable metals (the sum of the exchangeable and reducible fractions) within the tailings wetland are similar to values cited for natural wetlands. Estimated free-metal ion concentrations calculated from geochemical regression models indicate lower free-metal ion concentrations of Cd in the tailings wetland than natural wetlands and slightly higher free-metal ion concentrations of Pb and Zn. Increased concentrations of metals in roots, rhizomes and stems of emergent macrophytes did not occur in the tailings wetland. Even though a substantial number of Typha latifolia plants were found rooting directly into tailings, elevated metals were not found in these plant tissues. Phragmites also did not exhibit elevated metal concentrations in any plant tissues. Typha and Phragmites populations appear to be exhibiting metal-tolerant behaviour. The chemistry of the water column and sediments in Silvermines wetland were also investigated and were much more indicative of a wetland system impacted by heavy metal contamination than the tailings-wetland. Mean Dc, Fe, Mn, Pb and Zn concentrations in the water column and sediments of Silvermines wetlands were substantially higher than in the pilot wetlands and closely approximate concentrations in these matrices contaminated with metals from mining. In addition, mean sulphate concentration in Silvermines wetland was substantially higher and is closer to sulphate concentrations in waters associated with mining. Potentially bioavailable metals were substantially elevated in Silvermines wetland in comparison to the pilot wetlands and higher than those calculated for natural rive sediments. However, Fe oxy-hydroxide concentrations in Silvermines sediments are also much higher than in the pilot wetlands and this significantly impacts the concentration of free-metal ions in the sediment porewater. The free-metal ion concentrations for Pb and Zn indicate that Silvermines wetland is retaining metals and acting as a treatment wetland for drainage emanating from Silvermines tailings dam.