626 resultados para Marrubium vulgare
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Steam distillation of essential oils of aerial parts of Thymus capitatus and Marrubium vulgare L. collected at North cost of Egypt yielded 0.5% and 0.2%, respectively. Results of Gas chromatography-mass spectrometry analyses of the two samples identified 96.27% and 90.19% of the total oil composition for T. capitatus and M. vulgare, respectively. The two oil samples appeared dominated by the oxygenated constituents (88.22% for T. capitatus and 57.50% for M. vulgare), composed of phenols, mainly carvacrol (32.98%) and thymol (32.82%) in essential oil of T. capitatus, and thymol (34.55%) in essential oil of M. vulgare. It was evaluated the molluscicidal activity of T. capitatus and M. vulgare essential oils on adult and eggs of Biomphalaria alexandrina as well as their mosquitocidal activity on Culex pipiens. The LC50 and LC90 of T. capitatus essential oil against adult snails was 200 and 400 ppm/3hrs, respectively, while for M. vulgare it was 50 and 100 ppm/3hrs, respectively. Moreover, M. vulgare showed LC100 ovicidal activity at 200 ppm/24 hrs while T. capitatus oil showed no ovicidal activity. It was verified mosquitocidal activity, with LC50 and LC90 of 100 and 200 ppm/12hrs respectively for larvae, and 200 and 400 ppm/12hrs respectively for pupae of C. pipiens.
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One-third of botanical remedies from southern Italy are used to treat skin and soft tissue infections (SST's). Methicillin-resistant Staphylococcus aureus (MRSA), a common cause of SSTIs, is responsible for increased morbidity and mortality from infections. Therapeutic options are limited by antibiotic resistance. Many plants possess potent antimicrobial compounds for these disorders. Validation of traditional medical practices is important for the people who rely on medicinal plants. Moreover, identification of novel antibiotics and anti-pathogenic agents for MRSA is important to global healthcare.^ I took an ethnopharmacological approach to understand how Italian medicinal plants used for the treatment of SSTIs affect MRSA growth and virulence. My hypothesis was that plants used in folk remedies for SSTI would exhibit lower cytotoxicity and greater inhibition of bacterial growth, biofilm formation and toxin production in MRSA than plants used for remedies unrelated to the skin or for plants with no ethnomedical application. The field portion of my research was conducted in the Vulture-Alto Bradano area of southern Italy. I collected 104 plant species and created 168 crude extracts. In the lab, I screened samples for activity against MRSA in a battery of bioassays. Growth inhibition was analyzed using broth microtiter assays for determination of the minimum inhibitory concentration. Interference with quorum-sensing (QS) processes, which mediate pathogenicity, was quantified through RP-HPLC of δ-toxin production. Interference with biofilm formation and adherence was assessed using staining methods. The mammalian cytotoxicity of natural products was analyzed using MTT cell proliferation assay techniques.^ Although bacteriostatic activity was limited, extracts from six plants used in Italian folk medicine (Arundo donax, Ballota nigra, Juglans regia, Leopoldia comosa, Marrubium vulgare, and Rubus ulmifolius ) significantly inhibited biofilm formation and adherence. Moreover, plants used to treat SSTI demonstrated significantly greater anti-biofilm activity when compared to plants with no ethnomedical application. QSI activity was evident in 90% of the extracts tested and extracts from four plants ( Ballota nigra, Castanea saliva, Rosmarinus officinalis, and Sambucus ebulus) exhibited a significant dose-dependent response. Some of the plant remedies for SSTI identified in this study can be validated due to anti-MRSA activity.^
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BACKGROUND: Characterisation of the essential oils from O. glandulosum collected in three locations of Tunisia, chemical composition and the evaluation of their antioxidant activities were carried out. RESULTS: The essential oils from Origanum vulgare L. subsp. glandulosum (Desf.) letswaart collected from three localities of north Tunisia - Krib, Bargou and Nefza - were obtained in yields of 2.5, 3.0 and 4.6% (v/w), respectively. The essential oils were analysed by GC and GC/MS and assayed for their total phenolics content, by the Folin-Ciocalteu method, and antioxidant effectiveness, using the 2,2-diphenyl-1-picrylhydrazil (DPPH) radical scavenging assay. The main components of these essential oils, from Nefza, Bargou and Krib, were p-cymene (36%, 40% and 46%), thymol (32%, 39% and 18%), gamma-terpinene (24%, 12% and 16%) and carvacrol (2%, 2% and 15%), respectively). The ability to scavenge the DPPH radicals, expressed by IC50, ranged from 59 to 80 mg L-1. The total phenolic content, expressed in gallic acid equivalent (GAE) g kg(-1) dry weight, varied from 9.37 to 17.70 g kg(-1) dw. CONCLUSIONS: A correlation was identified between the total phenolic content of the essential oils and DPPH radical scavenger capacity. The occurrence of a p-cymene chemotype of O. glandulosum in the northern region of Tunisia is demonstrated.
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Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para obtenção do grau de Mestre em Tecnologia e Segurança Alimentar
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Dissertação para obtenção do Grau de Mestre em Tecnologia e segurança alimentar
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O tucumã (Astrocaryum vulgare Mart.) é um fruto nativo da Amazônia, de ocorrência principal no estado do Pará, mas também encontrado nos estados do nordeste e do centro-oeste brasileiro. O tucumã é considerado como uma excelente fonte de carotenóides com maior concentração em β-caroteno, precursor da vitamina A, e além dos carotenóides, também é importante fonte de vitamina B2 (riboflavina). Por este motivo, o presente trabalho objetivou analisar os efeitos da irradiação gama sobre o valor nutricional do tucumã. Os frutos de tucumã foram irradiados com as doses de 0,5, 1,0 e 2,0 kGy num irradiador com fonte de césio 137. Foram determinados os teores de carotenóides totais por espectrofotometria. As análises de α e β-caroteno, tiamina, riboflavina foram realizadas por cromatografia líquida de alta eficiência (CLAE). Foi detectado que o β-caroteno representa 80% dos carotenóides totais e que com uma dose de 2 kGy ocorreram as maiores reduções de β-caroteno, cerca de 7,5% em relação ao controle. Os frutos também apresentaram altos teores de riboflavina de 0,183 a 0,222 μg 100 g-1 e mantiveram a estabilidade após o processo de radiação gama, no entanto, os teores de tiamina foram baixos de 0,050 a 0,033 μg 100 g-1, e os frutos irradiados na dose de 2 kGy apresentaram reduções significativas de tiamina, cerca de 34% em relação ao controle.
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Es bien conocido que los fosfolípidos son un conjunto de moléculas capaces de funcionar como reguladores en diversos procesos celulares. Al respecto, este proyecto tiene como objetivo dilucidar la participación de los mismos, en particular ácido fosfatídico (PA) y diacilglicerol pirofosfato (DGPP) durante el efecto antagónico de ABA en la germinación y como reguladores de la respuesta al estrés salino en la plántula. Se sabe que las plantas responden de forma rápida y adecuada a una situación de estrés modificando el patrón de fosfolípidos de sus membranas, lo cual lleva a un cambio global en las actividad de lípido quinasas, fosfatasas y a la expresión/represión de genes particulares. El desarrollo de la propuesta permitiría responder dos cuestiones básicas: conocer la relación entre fosfolípidos y ABA e indagar su participación durante la señal de estrés. La relevancia de la propuesta radica en la necesidad de ampliar el conocimiento sobre una de las causas mas importantes "estrés salino" que afecta la germinación de la semilla y luego el crecimiento y desarrollo de la plántula. En principio se evaluara a nivel morfológico, bioquímico y molecular el efecto de ABA y de fosfolípidos. Se pretende indagar sobre cambios a nivel de vacuolización en protoplastos aislados, actividad de enzimas relacionadas, pH intracelular, nivel de fosfolípidos y enzimas implicadas en su metabolismo y también efectos sobre la expresión génica. Por otro lado, se analizara los niveles de fosfolípidos y enzimas relacionadas con su metabolismo en raíces y coleoptilos de semillas que germinaron bajo condiciones de estrés. Asimismo, se identificaran los cambios morfológicos provocados por el estrés en la longitud de coleóptilos y raíces. Por ultimo como indicador de una respuesta al estrés se evaluara los cambios en los niveles de prolina. La importancia del proyecto es determinar el papel que desempeñan PA y DGPP en la germinación y durante la respuesta al estrés.
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Plântulas de trigo (Triticum vulgare L.) da variedade Piratiní considerada suscetível ao "crestamento" foram cultivadas em solução nutritiva empregando-se a técnica das raízes divididas. As plantas submetidas aos tratamentos correspondentes às concentrações mais elevadas de alumínio, mostraram clorose nas folhas superiores e mais característicamente inibição no desenvolvimento das raízes mergulhadas nas soluções com alumínio. Os tratamentos provocaram alterações na composição das plantas em nitrogênio, fósforo, potássio, cálcio, magnésio e alumínio sem afetar o pêso da matéria sêca das diferentes par tes da planta com exceção das raízes em contato com o alumínio.
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Plântulas de trigo da variedade Piratiní suscetível ao "crestamento" e da variedade Colônias, considerada resistente, foram cultivadas em solução nutritiva empregando-se a técnica das raízes divididas. Estas variedades foram submetidas aos tratamentos correspondentes as concentrações de 0,2 a 6,0 ppm de alumínio, sendo aplicados 25 microcuries de fósforo radioativo que foram retirados posteriormente a fim de que fôsse determinada a sua translocação. Em ambas variedades observou-se que a concentração de alumínio nas fôlhas não influia na translocação do fósforo (32P) para as fôlhas novas. Entretanto, as relações entre os teores de alumínio nas fôlhas e os teores de fósforo nas fôlhas, hastes e raízes foram diferentes nas variedades estudadas.
Estudo comparativo de métodos para a avaliação do vigor de sementes de sorgo (Sorghum vulgare Pers.)
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o presente trabalho foi conduzido no sentido de comparar a eficiência de diferentes métodos para avaliar a.qualidade de sementes de sorgo (Sorghum vulgare Pers.). Foram comparados entre si os seguintes métodos: teste padrão de germinação, primeira contagem de germinação, velocidade de germinação, teste do cloreto de amônio, envelhecimento rápido, velocidade e porcentagem de emergência no campo. As análises dos dados e a interpretação dos resultados permitiram concluir que a eficiência dos métodos estudados depende da qualidade das sementes. o teste do cloreto de amônio e a velocidade de germinação foram os mais sensíveis às diferenças de vigor entre os tratamentos, enquanto que o teste padrão e a primeira contagem de germinação revelaram apenas as diferenças marcantes de qualidade.
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AIMS: To assess the impact of the biocontrol strain Pseudomonas fluorescens CHA0 on a collection of barley rhizosphere bacteria using an agar plate inhibition assay and a plant microcosm, focusing on a CHA0-sensitive member of the Cytophaga-like bacteria (CLB). METHODS AND RESULTS: The effect of strain CHA0 on a collection of barley rhizosphere bacteria, in particular CLB and fluorescent pseudomonads sampled during a growth season, was assessed by a growth inhibition assay. On average, 85% of the bacteria were sensitive in the May sample, while the effect was reduced to around 68% in the July and August samples. In the May sample, around 95% of the CLB and around 45% of the fluorescent pseudomonads were sensitive to strain CHA0. The proportion of CHA0-sensitive CLB and fluorescent pseudomonad isolates decreased during the plant growth season, i.e. in the July and August samples. A particularly sensitive CLB isolate, CLB23, was selected, exposed to strain CHA0 (wild type) and its genetically modified derivatives in the rhizosphere of barley grown in gnotobiotic soil microcosms. Two dry-stress periods were imposed during the experiment. Derivatives of strain CHA0 included antibiotic or exopolysaccharide (EPS) overproducing strains and a dry-stress-sensitive mutant. Despite their inhibitory activity against CLB23 in vitro, neither wild-type strain CHA0, nor any of its derivatives, had a major effect on culturable and total cell numbers of CLB23 during the 23-day microcosm experiment. Populations of all inoculants declined during the two dry-stress periods, with soil water contents below 5% and plants reaching the wilting point, but they recovered after re-wetting the soil. Survival of the dry-stress-sensitive mutant of CHA0 was most affected by the dry periods; however, this did not result in an increased population density of CLB23. CONCLUSIONS: CLB comprise a large fraction of barley rhizosphere bacteria that are sensitive to the biocontrol pseudomonad CHA0 in vitro. However, in plant microcosm experiments with varying soil humidity conditions, CHA0 or its derivatives had no major impact on the survival of the highly sensitive CLB strain, CLB23, during two dry-stress periods and a re-wetting period; all co-existed well in the rhizosphere of barley plants. SIGNIFICANCE AND IMPACT OF THE STUDY: Results indicate a lack of interaction between the biocontrol pseudomonad CHA0 and a sensitive CLB when the complexity increases from agar plate assays to plant microcosm experiments. This suggests the occurrence of low levels of antibiotic production and/or that the two bacterial genera occupy different niches in the rhizosphere.
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Drought limits plant growth and threatens crop productivity. A barley (Hordeum vulgare) ethylene imine-induced monogenic recessive mutant cer-zv, which is sensitive to drought, was characterized and genetically mapped in the present study. Detached leaves of cer-zv lost 34.2 % of their initial weight after 1 h of dehydration. The transpiration was much higher in cer-zv leaves than in wild-type leaves under both light and dark conditions. The stomata of cer-zv leaves functioned normally, but the cuticle of cer-zv leaves showed increased permeability to ethanol and toluidine blue dye. There was a 50-90 % reduction in four major cutin monomers, but no reduction in wax loads was found in the cer-zv mutant as compared with the wild type. Two F(2) mapping populations were established by the crosses of 23-19 × cer-zv and cer-zv × OUH602. More polymorphisms were found in EST sequences between cer-zv and OUH602 than between cer-zv and 23-19. cer-zv was located in a pericentromeric region on chromosome 4H in a 10.8 cM interval in the 23-19 × cer-zv map based on 186 gametes tested and a 1.7 cM interval in the cer-zv × OUH602 map based on 176 gametes tested. It co-segregated with EST marker AK251484 in both maps. The results indicated that the cer-zv mutant is defective in cutin, which might be responsible for the increased transpiration rate and drought sensitivity, and that the F(2) of cer-zv × OUH602 might better facilitate high resolution mapping of cer-zv.
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O objetivo deste trabalho foi estimar a variabilidade e a divergência genética entre genótipos de tucumanzeiro-do-pará promissores para a produção de frutos por marcadores de RAPD. Foram coletadas amostras de folhas de 29 plantas-matrizes selecionadas no Banco Ativo de Germoplasma da Embrapa Amazônia Oriental, com base na produção de frutos por planta, mas com pronunciadas variações para outras características. As amostras de DNA foram amplificadas por 24 iniciadores RAPD e analisadas por três métodos multivariados, usando a matriz de dissimilaridades genéticas obtidas pelo complemento aritmético do coeficiente de Jaccard. Foram gerados 332 marcadores moleculares que expressaram 98,5% de polimorfismo. Os marcadores RAPD apresentaram poder de discriminação eficiente entre os 29 genótipos avaliados, constatando-se distância genética média entre os genótipos de 51,7%, variando entre 26,9% e 71,5%. A maior média de distância ocorreu entre o genótipo 22 e os demais, com 66,8%. Os genótipos formaram oito e quinze grupos distintos, possivelmente grupos heteróticos, pelos métodos de agrupamentos UPGMA e Tocher, respectivamente. As análises das coordenadas principais confirmaram a alta variabilidade entre os genótipos. Os marcadores moleculares utilizados permitiram a identificação de ampla variabilidade e forte divergência genética entre os genótipos com ausência de duplicatas, o que possibilita a indicação desses materiais para compor programa de melhoramento genético para a produção de frutos.