Base de dados : LILACS
Pesquisa : G03.493.875 [Categoria DeCS]
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Id: biblio-950733
Autor: Cetin, Emine Sema.
Título: Induction of secondary metabolite production by UV-C radiation in Vitis vinifera L. Öküzgözü callus cultures
Fonte: Biol. Res;47:1-7, 2014. tab.
Idioma: en.
Resumo: BACKGROUND: The aim of the present work was to examine the role of UV-C irradiation on the production of secondary metabolites (total phenolic, total flavanols, total flavonols, catechin, ferulic acid and trans-resveratrol in phenolic compounds and α-, ß-, γ- δ-tocopherols) in callus cultures. Studies on the effects of UV-C treatment on callus culture are seldom and generally focused on UV-B. However UV-C radiation play an important role in accumule secondary metabolites. RESULTS: In this study, callus cultures from Öküzgözü grape cultivar were initiated from leaf petiole explants. Calli formed after 6 weeks on the medium supplemented with 0.5 mg L-1 benzylaminopurine (BA), 0.5 mg L-1 indole acetic acid (IAA) on B5 media. Callus tissues were exposed to UV-C irradiation at 10, 20 and 30 cm distances from the UV source for 5 and 10 minutes and samples were collected at hours 0, 24 and 48. CONCLUSIONS: The greatest total phenolic content (155.14 mg 100 g-1) was detected in calli exposed to UV-C for 5 min from 30 cm distance and sampled after 24 h. 24 h and 48 h incubation times, 30 cm and 5 min were the most appropriate combination of UV-C application in total flavanol content. Maximum total flavonol content (7.12 mg 100 g-1) was obtained on 0 h, 5 min and 20 cm combination. The highest (+)- catechin accumulation (8.89 mg g-1) was found in calli with 10 min UV-C application from 30 cm distance and sampled after 48 h. Ferulic acid content increased 6 fold in Öküzgözü callus cultures (31.37 µg g-1) compared to the control group. The greatest trans-resveratrol content (8.43 µg g-1) was detected in calli exposed to UV-C for 5 min from 30 cm distance and sampled after 24 h. The highest α-tocopherol concentration was found in calli exposed to UV-C for 10 min from 30 cm distance and sampled after 24 h. As a conclusion, it was showed that UV-C radiation had remarkable promoting effects on the accumulation of secondary metabolites in the calli of Öküzgözü grape cultivar.
Descritores: Raios Ultravioleta
Folhas de Planta/efeitos da radiação
Produtos Agrícolas/efeitos da radiação
Vitis/efeitos da radiação
Técnicas de Embriogênese Somática de Plantas/métodos
Metabolismo Secundário/efeitos da radiação
-Fenóis/análise
Estilbenos/análise
Flavonoides/análise
Catequina/análise
Cromatografia
Folhas de Planta/metabolismo
Folhas de Planta/química
Produtos Agrícolas/fisiologia
Ácidos Cumáricos/análise
Vitis/metabolismo
Vitis/química
Tocoferóis/análise
Flavonóis/análise
Metabolismo Secundário/fisiologia
Resveratrol
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-950743
Autor: Cetin, Emine Sema; Babalik, Zehra; Hallac-Turk, Filiz; Gokturk-Baydar, Nilgun.
Título: The effects of cadmium chloride on secondary metabolite production in Vitis vinifera cv. cell suspension cultures
Fonte: Biol. Res;47:1-6, 2014. graf, tab.
Idioma: en.
Resumo: BACKGROUND: Plant secondary metabolites are possess several biological activities such as anti-mutagenic, anti-carcinogenic, anti-aging, etc. Cell suspension culture is one of the most effective systems to produce secondary metabolites. It is possible to increase the phenolic compounds and tocopherols by using cell suspensions. Studies on tocopherols production by cell suspension cultures are seldom and generally focused on seed oil plants. Although fresh grape, grape seed, pomace and grape seed oil had tocopherols, with our best knowledge, there is no research on tocopherol accumulation in the grape cell suspension cultures. In this study, it was aimed to determine the effects of cadmium chloride treatments on secondary metabolite production in cell suspension cultures of grapevine. Cell suspensions initiated from callus belonging to petiole tissue was used as a plant material. Cadmium chloride was applied to cell suspension cultures in different concentration (1.0 mM and 1.5 mM) to enhance secondary metabolite (total phenolics, total flavanols, total flavonols, trans-resveratrol, and α-, ß-, γ- δ-tocopherols) production. Cells were harvested at two days intervals until the 6th day of cultures. Amounts of total phenolics, total flavanols and total flavonols; trans-resveratrol and tocopherols (α-, ß-, γ- and δ-tocopherols) and dry cell weights were determined in the harvested cells. RESULTS: Phenolic contents were significantly affected by the sampling time and cadmium concentrations. The highest values of total phenolic (168.82 mg/100 g), total flavanol (15.94 mg/100 g), total flavonol (14.73 mg/100 g) and trans-resveratrol (490.76 µg/100 g) were found in cells treated with 1.0 mM CdCl2 and harvested at day 2. Contents of tocopherols in the cells cultured in the presence of 1.0 mM CdCl2 gradually increased during the culture period and the highest values of α, ß and γ tocopherols (145.61, 25.52 and 18.56 µg/100 g) were detected in the cell cultures collected at day 6. CONCLUSIONS: As a conclusion, secondary metabolite contents were increased by cadmium chloride application and sampling time, while dry cell weights was reduced by cadmium chloride treatments.
Descritores: Cloreto de Cádmio/farmacologia
Vitis/efeitos dos fármacos
Cultura Primária de Células/métodos
Metabolismo Secundário/efeitos dos fármacos
-Fenóis/análise
Estilbenos/análise
Flavonoides/análise
Folhas de Planta/crescimento & desenvolvimento
Folhas de Planta/efeitos dos fármacos
Folhas de Planta/metabolismo
Folhas de Planta/química
Vitis/crescimento & desenvolvimento
Vitis/metabolismo
Vitis/química
Tocoferóis/análise
Flavonóis/análise
Proliferação de Células/efeitos dos fármacos
Técnicas de Embriogênese Somática de Plantas/métodos
Resveratrol
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-950780
Autor: Habu, Josiah Bitrus; Ibeh, Bartholomew Okechukwu.
Título: In vitro antioxidant capacity and free radical scavenging evaluation of active metabolite constituents of Newbouldia laevis ethanolic leaf extract
Fonte: Biol. Res;48:1-10, 2015. graf, tab.
Idioma: en.
Resumo: BACKGROUND: The aim of the present study was to evaluate the in vitro antioxidant and free radical scavenging capacity of bioactive metabolites present in Newbouldia laevis leaf extract. RESULTS: Chromatographic and spectrophotometric methods were used in the study and modified where necessary in the study. Bioactivity of the extract was determined at 10 µg/ml, 50 µg/ml, 100 µg/ml, 200 µg/ml and 400 µg/ml concentrations expressed in % inhibition. The yield of the ethanolic leaf extract of N.laevis was 30.3 g (9.93%). Evaluation of bioactive metabolic constituents gave high levels of ascorbic acid (515.53 ± 12 IU/100 g [25.7 mg/100 g]), vitamin E (26.46 ± 1.08 IU/100 g), saponins (6.2 ± 0.10), alkaloids (2.20 ± 0.03), cardiac glycosides(1.48 ± 0.22), amino acids and steroids (8.01 ± 0.04) measured in mg/100 g dry weight; moderate levels of vitamin A (188.28 ± 6.19 IU/100 g), tannins (0.09 ± 0.30), terpenoids (3.42 ± 0.67); low level of flavonoids (1.01 ± 0.34 mg/100 g) and absence of cyanogenic glycosides, carboxylic acids and aldehydes/ketones. The extracts percentage inhibition of DPPH, hydroxyl radical (OH.), superoxide anion (O2 .-), iron chelating, nitric oxide radical (NO), peroxynitrite (ONOO-), singlet oxygen (1O2), hypochlorous acid (HOCl), lipid peroxidation (LPO) and FRAP showed a concentration-dependent antioxidant activity with no significant difference with the controls. Though, IC50 of the extract showed significant difference only in singlet oxygen (1O2) and iron chelating activity when compared with the controls. CONCLUSIONS: The extract is a potential source of antioxidants/free radical scavengers having important metabolites which maybe linked to its ethno-medicinal use.
Descritores: Extratos Vegetais/isolamento & purificação
Sequestradores de Radicais Livres/isolamento & purificação
Folhas de Planta/química
Bignoniaceae/química
Metaboloma/fisiologia
Antioxidantes/isolamento & purificação
-Fenóis/análise
Vitaminas/isolamento & purificação
Vitaminas/metabolismo
Flavonoides/análise
Extratos Vegetais/farmacologia
Peroxidação de Lipídeos/fisiologia
Quelantes de Ferro/isolamento & purificação
Espécies Reativas de Oxigênio/isolamento & purificação
Radical Hidroxila/análise
Concentração Inibidora 50
Metabolismo Secundário/fisiologia
Nigéria
Óxido Nítrico/metabolismo
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-1019503
Autor: Isah, Tasiu.
Título: Stress and defense responses in plant secondary metabolites production
Fonte: Biol. Res;52:39, 2019. tab, graf.
Idioma: en.
Resumo: In the growth condition(s) of plants, numerous secondary metabolites (SMs) are produced by them to serve variety of cellular functions essential for physiological processes, and recent increasing evidences have implicated stress and defense response signaling in their production. The type and concentration(s) of secondary molecule(s) produced by a plant are determined by the species, genotype, physiology, developmental stage and environmental factors during growth. This suggests the physiological adaptive responses employed by various plant taxonomic groups in coping with the stress and defensive stimuli. The past recent decades had witnessed renewed interest to study abiotic factors that influence secondary metabolism during in vitro and in vivo growth of plants. Application of molecular biology tools and techniques are facilitating understanding the signaling processes and pathways involved in the SMs production at subcellular, cellular, organ and whole plant systems during in vivo and in vitro growth, with application in metabolic engineering of biosynthetic pathways intermediates.
Descritores: Reguladores de Crescimento de Plantas/metabolismo
Estresse Fisiológico/fisiologia
Fenômenos Fisiológicos Vegetais
Metabolismo Secundário/fisiologia
-Plantas/metabolismo
Transdução de Sinais
Brotos de Planta/metabolismo
Raízes de Plantas/metabolismo
Regulação da Expressão Gênica de Plantas/fisiologia
Técnicas de Cultura de Células
Tipo de Publ: Revisão
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-839326
Autor: Braga, Raíssa Mesquita; Dourado, Manuella Nóbrega; Araújo, Welington Luiz.
Título: Microbial interactions: ecology in a molecular perspective
Fonte: Braz. j. microbiol;47(supl.1):86-98, Oct.-Dec. 2016. tab.
Idioma: en.
Projeto: Foundation for Research Assistance; . FAPESP; . CNPq.
Resumo: ABSTRACT The microorganism-microorganism or microorganism-host interactions are the key strategy to colonize and establish in a variety of different environments. These interactions involve all ecological aspects, including physiochemical changes, metabolite exchange, metabolite conversion, signaling, chemotaxis and genetic exchange resulting in genotype selection. In addition, the establishment in the environment depends on the species diversity, since high functional redundancy in the microbial community increases the competitive ability of the community, decreasing the possibility of an invader to establish in this environment. Therefore, these associations are the result of a co-evolution process that leads to the adaptation and specialization, allowing the occupation of different niches, by reducing biotic and abiotic stress or exchanging growth factors and signaling. Microbial interactions occur by the transference of molecular and genetic information, and many mechanisms can be involved in this exchange, such as secondary metabolites, siderophores, quorum sensing system, biofilm formation, and cellular transduction signaling, among others. The ultimate unit of interaction is the gene expression of each organism in response to an environmental (biotic or abiotic) stimulus, which is responsible for the production of molecules involved in these interactions. Therefore, in the present review, we focused on some molecular mechanisms involved in the microbial interaction, not only in microbial-host interaction, which has been exploited by other reviews, but also in the molecular strategy used by different microorganisms in the environment that can modulate the establishment and structuration of the microbial community.
Descritores: Plantas/microbiologia
Ecologia
Interações Hospedeiro-Patógeno
Interações Microbianas
Microbiota
-Microbiologia do Solo
Percepção de Quorum
Metabolismo Secundário
Limites: Animais
Responsável: BR1.1 - BIREME


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Id: biblio-889240
Autor: Ser, Hooi-Leng; Tan, Wen-Si; Mutalib, Nurul-Syakima Ab; Yin, Wai-Fong; Chan, Kok-Gan; Goh, Bey-Hing; Lee, Learn-Han.
Título: Genome sequence of Streptomyces gilvigriseus MUSC 26T isolated from mangrove forest
Fonte: Braz. j. microbiol;49(2):207-209, Apr.-June 2018. tab.
Idioma: en.
Projeto: PVC Award Grant; . Biotek Abadi; . MOSTI eScience funds; . UM-MOHE HIR Nature Microbiome.
Resumo: Abstract Streptomycetes remain as one of the important sources for bioactive products. Isolated from the mangrove forest, Streptomyces gilvigriseus MUSC 26T was previously characterised as a novel streptomycete. The high quality draft genome of MUSC 26T contained 5,213,277 bp with G + C content of 73.0%. Through genome mining, several gene clusters associated with secondary metabolites production were revealed in the genome of MUSC 26T. These findings call for further investigations into the potential exploitation of the strain for production of pharmaceutically important compounds.
Descritores: Streptomyces/genética
Genoma Bacteriano
Microbiologia Ambiental
-Streptomyces/isolamento & purificação
Composição de Bases
Produtos Biológicos/metabolismo
Análise de Sequência de DNA
Biologia Computacional
Áreas Alagadas
Redes e Vias Metabólicas/genética
Metabolismo Secundário
Responsável: BR1.1 - BIREME


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Id: biblio-836666
Autor: Dörr, Fabiane.
Título: Efeito do herbicida glifosato sobre o crescimento e produção de metabólitos secundários em Microcystis aeruginosa e Cylindrospermopsis raciborskii / The effect of herbicide glyphosate on the growth and of secondary metabolites production in Microcystis aeruginosa and Cylindrospermopsis raciborskii.
Fonte: São Paulo; s.n; abr. 2015. 207 p. tab, graf, ilus.
Idioma: pt.
Tese: Apresentada a Universidade de São Paulo para obtenção do grau de Doutor.
Resumo: ianobactérias, conhecidas por sua habilidade de sintetizar metabólitos com ação tóxica, podem se tornar dominantes em águas com altas concentrações de nitrogênio e fósforo. Embora a toxicidade do glifosato, o herbicida mais usado no mundo, em alguns organismos aquáticos seja conhecida, poucos estudos abordam o efeito desse composto sobre a produção de metabólitos secundários por cianobactérias. O objetivo deste trabalho foi avaliar a influência de diferentes concentrações de glifosato (produto técnico) sobre o crescimento e produção de cianotoxinas e microgininas pelas cepas brasileiras Microcystis aeruginosa LTPNA 08 e Cylindrospermopsis raciborskii CENA 302. Na presença de 15 mg/L de glifosato, o crescimento e a produção de toxinas pela M. aeruginosa foram reduzidos e de microgininas significativamente aumentada. Já a C. raciborskii, quando exposta à 20 mg/L de glifosato teve seu crescimento e síntese de clorofila-a, carotenoides e saxitoxinas aumentados. Concentrações superiores a 20 e 30 mg/L impediram o crescimento celular das cepas LTPNA 08 e CENA 302, respectivamente. A análise de ácidos graxos mostrou perfis bastante distintos entre as cepas. Na cepa LTPNA 08, enquanto que na presença de 10 mg/L de glifosato ocorreu diminuição do teor do ácido linoleico, o ácido estearidônico foi aumentado. Nenhuma das concentrações testadas promoveu alteração sobre o perfil de ácidos graxos da cepa CENA 302. A toxicidade de 5 produtos formulados a base de glifosato foi comparada ao produto técnico em ambas as linhagens-teste. Observou-se uma resistência distinta entre as cepas e toxicidade também variável entre as formulações comerciais. Sendo assim, diante da elevada resistência das cianobactérias M. aeruginosa e C. raciborskii ao glifosato, e considerando-se a elevada interferência antrópica através das práticas agrícolas, pode-se inferir que o uso excessivo e frequente desse herbicida é capaz de estimular o crescimento e dominância desses organismos, podendo modificar a estrutura e funcionalidade de ecossistemas aquáticos

Cyanobacteria, known for their ability to synthesize toxic metabolites, can become dominant in water bodies with high concentrations of nitrogen and phosphorus. Although the toxicity of glyphosate, the most widely used herbicide in the world, in some aquatic organisms is well known, few studies address the effect of this compound on the production of secondary metabolites by cyanobacteria. The aim of this study was to evaluate the influence of different concentrations the herbicide glyphosate (technical grade) on growth and production of cyanotoxins and microginins by Brazilian strains of Microcystis aeruginosa LTPNA 08 and Cylindrospermopsis raciborskii CENA 302. In the presence of 15 mg/L of glyphosate, growth and toxin production by M. aeruginosa were reduced and microginins cell quota significantly increased. The C. raciborskii strain, when exposed to 20 mg/L of glyphosate, had the growth, and chlorophyll-a, carotenoids and saxitoxins production increased. Concentrations above 20 and 30 mg/L prevented cell growth of LTPNA 08 and CENA 302 strains, respectively. Fatty acid analysis showed distinct profiles among the strains. When exposed to 10 mg/L of glyphosate, a decrease in the linoleic acid and increase in stearidonic acid content were observed in M. aeruginosa LTPNA 08 strain. None of the tested concentrations of glyphosate promoted change on the fatty acid profile of CENA 302 strain. The toxicity of 5 glyphosate formulated products was compared to technical product to both strains. There was a distinct resistance among strains and also a variable toxicity among formulated products. Thus, given the high glyphosate resistance of M. aeruginosa and C. raciborskii cyanobacteria, and considering the high anthropogenic interference through agri cultural practices, it can be inferred that excessive and frequent use of this herbicide is able to stimulate growth and dominance of these organisms, which may modify the structure and function of aquatic ecosystems
Descritores: GROWTH & DEVELOPMENT
Crescimento
Herbicidas/análise
Microcystis/classificação
-Cianobactérias
Cylindrospermopsis/classificação
Metabolismo Secundário/fisiologia
Toxicologia
Responsável: BR40.1 - DBD - Divisão de Biblioteca e Documentacão do Conjunto das Químicas
BR40.1; T 615.9, D716e. 30100021820-F


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Id: biblio-830064
Autor: FERRERA, T S; HELDWEIN, A B; DOS SANTOS, C O; SOMAVILLA, J C; SAUTTER, C K.
Título: Substâncias fenólicas, flavonoides e capacidade antioxidante em erveiras sob diferentes coberturas do solo e sombreamentos / Phenolic Substances, Flavonoids, and Antioxidant Capacity in Herbs under Different Soil Covers and Shadings
Fonte: Rev. bras. plantas med;18(2,supl.1):588-596, 2016. tab.
Idioma: pt.
Resumo: RESUMO Objetivou neste trabalho analisar a concentração de polifenóis totais, flavonoides e capacidade antioxidantes por meio dos métodos ABTS e FRAP, em erveiras jovens cultivadas em solo coberto e com sombreamento. Mudas de erva-mate foram submetidas aos tratamentos com solos cobertos e desnudos em sombreamentos de 0, 18, 35 e 50%, após sete e onze meses de cultivo, verão e outono, respectivamente. Foram coletadas folhas maduras para realização dos extratos utilizados para as análises de compostos fenólicos por meio da reação de oxirredução com reagente de Folin-Ciocalteu, flavonoides por método colorimétrico e capacidade antioxidante por frente ao radical ABTS e poder de redução do ferro (FRAP). O teor de compostos fenólicos foi maior nos tratamentos com 35% de sombreamento em comparação ao grupo dos flavonoides e capacidade antioxidante, o que foi demonstrado pela correlação do sombreamento com estes parametros. No método FRAP a maior correlação demonstra que o outono é a melhor época de colheita por apresentar maior concentração de compostos fitoquímicos. Ficou evidente a influência positiva dos sombreamentos (35 e 50%) no teor de compostos fenólicos e flavonoides relacionados à capacidade antioxidante e à qualidade da erva-mate para atender ao mercado consumidor.

ABSTRACT This study aimed to analyze the concentration of total polyphenols, flavonoids, and antioxidant capacity, by the methods ABTS and FRAP, in young herbs grown in covered and shaded soil. Yerba mate seedlings were subjected to treatment with bare and covered soils in shadings of 0, 18, 35, and 50%, after seven and eleven months cultivation, summer and fall, respectively. Mature leaves were collected to perform the analyses of phenolic compounds by redox reaction with Folin-Ciocalteu reagent, of flavonoids by colorimetric method, and of antioxidant capacity by ABTS radical and FRAP (iron reduction method). The content of phenolic compounds was higher in the treatments with 35% shading in correlation with the group of flavonoids and antioxidant capacity. In the FRAP method, the higher correlation shows that autumn is the best time to harvest because of the higher concentration of phytochemical compounds. The positive influence of shading (35 and 50%) was evident in the content of phenolic compounds and flavonoids related to antioxidant capacity and better quality of yerba mate to meet the consumer market.
Descritores: Antioxidantes/análise
Flavonoides/análise
Ilex paraguariensis/crescimento & desenvolvimento
Compostos Fenólicos/análise
-Recuperação de Fluorescência Após Fotodegradação/métodos
Metabolismo Secundário
Responsável: BR1.1 - BIREME


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Id: lil-763230
Autor: STORCK, R. C.; DESCHAMPS, C..
Título: Teor e composição do óleo essencial de patchouli (Pogostemon cablin (Blanco) Benth. ) após diferentes tempos de secagem em estufa e temperatura ambiente / Yield and composition of essential oil of patchouli (Pogostemon cablin (Blanco) Benth. ) after different drying periods in oven and at room temperatur
Fonte: Rev. bras. plantas med;17(4):570-576, out.-dez. 2015. tab, graf.
Idioma: pt.
Resumo: RESUMOPatchouli é uma espécie aromática pertencente à família Lamiaceae que possui óleo essencial com alto valor comercial devido à aplicação nas indústrias de higiene, cosméticos e perfumarias. Considerando as características voláteis e estruturas de armazenamento em diferentes órgãos das plantas aromáticas, a determinação de métodos de secagem é de extrema importância e pode afetar tanto o rendimento como a composição do óleo essencial. Este trabalho teve como objetivo principal avaliar o teor e a composição do óleo essencial de patchouli após secagem por diferentes períodos em estufa e a temperatura ambiente. O experimento foi realizado durante o mês de fevereiro de 2011 em delineamento experimental inteiramente casualizado em esquema fatorial 2X6, correspondente a dois métodos de secagem (estufa 65ºC e temperatura ambiente) e seis tempos para o início da extração do óleo essencial após a (0, 2, 4,6,8 e 10 dias após a colheita),com três repetições. O óleo essencial foi extraído por meio hidrodestilação em aparelho graduado de Clevenger e os constituintes do óleo essencial foram analisados por cromatografia em fase gasosa acoplada à espectrometria de massas. Houve interação significativa entre os métodos e tempos de secagem tanto para o teor como para a composição do óleo essencial. A secagem das plantas por dois dias em estufa a 65ºC aumentou o teor de óleo essencial, após este período houve redução significativa. Para as folhas secas em temperatura ambiente, o teor de óleo essencial foi superior aos quatro e aos seis dias após a colheita. Comparando-se os métodos, a secagem em estufa mostrou-se mais eficiente, sendo o teor significativamente superior após dois dias de secagem. Após este período, no entanto, houve drástica redução do teor de óleo essencial, sendo inferior ao teor observado em todos os períodos nas folhas secas em temperatura ambiente. Os diferentes métodos e tempos de secagem alteraram também a composição do óleo essencial. Embora a secagem em estufa a 65º por dois dias não tenha resultado em redução dos teores dos constituintes majoritários patchoulol e pogostol, maiores teores foram observados após seis ou oito dias de secagem. Quando a secagem foi realizada a temperatura ambiente, não houve alteração dos teores de ambos os constituintes.

ABSTRACTPatchouli is an aromatic species belonging to the Lamiaceae family that has essential oil with high commercial value to the hygiene, cosmetic and perfume industries. Considering its volatile characteristics and storage structures in different organs of aromatic plants, the determination of drying methods is extremely important and can affect both the yield and the composition of the essential oil. This work aimed to evaluate the content and composition of the patchouli essential oil after drying it in different periodin an oven and at room temperature. The trial was carried out in February 2011 at an experimental design completely randomized in 2X6 factorial scheme, corresponding to two drying methods (oven at 65˚C and room temperature) and six periods of essential oil extraction after harvest (0, 2, 4, 6, 8, and 10 days after harvest), with three replications. The essential oil was extracted by hydrodistillation in a Clevenger apparatus and the essential oil components were analyzed by gas chromatography coupled to mass spectrometry. There was significant interaction among the methods and drying times for both the content as well as for the composition of essential oil. The drying of the plants for two days in an oven at 65˚C increased the essential oil content; after this period, there was a significant reduction. For the leaves that dried at room temperature, their contentof essential oil was superior at the fourth and sixth days after the harvest. When comparing the methods, the drying in the oven was more efficient, with the oil content being significantly higher after two days of drying. After this period, however, there was a drastic reduction in the essential oil content, lower than the one observed in all periods when the leaves dried at room temperature. The different methods and drying periods also altered the essential oil`s composition. Although drying in oven at 65˚ for two days did not result in reduction of the contents of patchoulol and pogostol, higher contents were observed after six or eight days of drying. When drying was carried out at room temperature, no change in relative content of both components was observed.
Descritores: Estufas para Plantas/classificação
Óleos Voláteis/metabolismo
Pogostemon
Temperatura
-Metabolismo Secundário
Responsável: BR1.1 - BIREME


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Id: lil-705250
Autor: Gomes, Elisângela Soares; Schuch, Viviane; Lemos, Eliana Gertrudes de Macedo.
Título: Biotechnology of polyketides: new breath of life for the novel antibiotic genetic pathways discovery through metagenomics
Fonte: Braz. j. microbiol;44(4):1007-1034, Oct.-Dec. 2013. ilus, graf, tab.
Idioma: en.
Resumo: The discovery of secondary metabolites produced by microorganisms (e.g., penicillin in 1928) and the beginning of their industrial application (1940) opened new doors to what has been the main medication source for the treatment of infectious diseases and tumors. In fact, approximately 80 years after the discovery of the first antibiotic compound, and despite all of the warnings about the failure of the "goose that laid the golden egg," the potential of this wealth is still inexorable: simply adjust the focus from "micro" to "nano", that means changing the look from microorganisms to nanograms of DNA. Then, the search for new drugs, driven by genetic engineering combined with metagenomic strategies, shows us a way to bypass the barriers imposed by methodologies limited to isolation and culturing. However, we are far from solving the problem of supplying new molecules that are effective against the plasticity of multi- or pan-drug-resistant pathogens. Although the first advances in genetic engineering date back to 1990, there is still a lack of high-throughput methods to speed up the screening of new genes and design new molecules by recombination of pathways. In addition, it is necessary an increase in the variety of heterologous hosts and improvements throughout the full drug discovery pipeline. Among numerous studies focused on this subject, those on polyketide antibiotics stand out for the large technical-scientific efforts that established novel solutions for the transfer/engineering of major metabolic pathways using transposons and other episomes, overcoming one of the main methodological constraints for the heterologous expression of major pathways. In silico prediction analysis of three-dimensional enzymatic structures and advances in sequencing technologies have expanded access to the metabolic potential of microorganisms.
Descritores: Antibacterianos/metabolismo
Vias Biossintéticas/genética
Biotecnologia/métodos
Descoberta de Drogas/métodos
Metagenômica/métodos
Policetídeos/metabolismo
-Antibacterianos/isolamento & purificação
Biotecnologia/tendências
Descoberta de Drogas/tendências
Engenharia Metabólica/métodos
Engenharia Metabólica/tendências
Metagenômica/tendências
Policetídeos/isolamento & purificação
Metabolismo Secundário
Limites: Animais
Humanos
Tipo de Publ: Research Support, Non-U.S. Gov't
Revisão
Responsável: BR1.1 - BIREME



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