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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Stanovení nikotinu v různých typech výrobků / Analysis of nicotin content in some products

Pražáková, Jana January 2015 (has links)
This diploma thesis deals with the determination of nicotine in different products. The theoretical part summarizes review on nicotine, smoking and opportunities how to quit. In the practical part a method for the determination of nicotine by HPLC / PDA was optimized. As the most suitable stationary phase was selected a Kinetex 5u C18 100A 150 x 4.6 mm column, as the optimal mobile phase was chosen a pure methanol with a flow rate of 1 ml min-1 and a temperature of 25 °C. For the analysis of nicotine were chosen: 18 kinds of cartridges for electronic cigarettes, two kinds of nicotine gum, nicotine spray, nicotine pastilles, nicotine orodispersible film and ten species of classic cigarettes. For each type of product the most appropriate method for extracting nicotine and its subsequent analysis by HPLC / PDA was found. For tobacco 24 hour extraction in methanol and 10s ultrasound was selected. The nicotine spray and electronic cigarette refills without flavours were only diluted with methanol. Flavoured refills were first diluted by sodium hydroxide and then with methanol. For chewing gums, pastilles and nicotine film extraction with 5% sodium hydroxide was chosen. In this study also new experimental nicotine product was designed. Nicotine has been encapsulated in alginate-starch material to form small gel particles. As the most suitable medium for storage the water medium was determined.
42

Device aggregation with data networking : Implementing a Personal Area Network

Zhang, Shasha January 2008 (has links)
Technology is advancing rapidly and intelligent devices are becoming affordable and wireless infrastructure is becoming pervasive. Personal information technology appliances have become part of our life, via cellular phones, PDAs, Bluetooth headsets, handheld keyboards, GPS, and digital cameras. In the future, new intelligent devices will be invented as technology evolves. However, because multiple devices provide similar (but different) functionality it is complex for the average user to choose a single device. Moreover, today it is hard to configure, administer, and use several different appliances together. In order to be utilized in an effective manner and in an accessible way, personal devices should be aggregated, i.e., connected together via a local area network so that they can appear to the user as if they were a single device. This paper introduces a connection model based on device aggregation to realize shared state, the behavior of a shared appliance, and with the superset of the individual device functionality. Such an aggregated logical device might even exhibit functions which a user would have a very hard time realizing by manually combining devices. This will facilitate the user’s control over their appliances (build of different devices), but acting as one device. The project was a joint effort with David Sabaté Mogica. We developed such a system based on Dynamic Host Client protocol (DHCP) and Service Location Protocol (SLP) for service discovery and Virtual Network Computing (VNC) for remote desktop control. The system builds on a laboratory network environment. This thesis concerns the implementation and evaluation of service discovery. The Remote desktop control was researched and implemented separately and will be reported separately. Service discovery between two computers has been implemented using a custom program developed for a PDA. However, at present the PDA only sends a DA request packet with DHCP. However, service discovery has been successfully tested between two computers. This provided an important base for the programming on PDA and the future development of a similar program for a cellular phone. / Den snabba tekniska utvecklingen ger våra apparater mer och mer intelligens, priset på avancerade produkter är överkomligt och trådlösa infrastrukturer binder samman allt fler produkter. Tekniska produkter har blivit en del av vår vardag: Mobiltelefon, PDA-er, trådlösa hörlurar och tangentbord med blåtandsradio, GPS och digitalkameror. I takt med den tekniska utvecklingen kommer hela tiden nya intelligenta och kommunicerande produkter. Man kan hitta liknande funktioner i olika produkter, och det är svårt för den vanlige användaren att välja den optimala produkten. Dessutom har de avancerade produkterna många parametrar att ställa in, och att använda olika produkter tillsammans kräver att användaren är djupt insatt i tekniken. Genom att aggregera, koppla ihop, produkterna i ett lokalt nätverk, kan deras funktioner användas effektivt och göras bättre tillgängliga genom att de för användaren ser ut som om de tillhör en enda produkt. Denna avhandling introducerar en kommunikationsmodell baserad på produktaggregering genom delade gemensamma tillstånd och reaktioner hos de ingående produkterna, med tillägg av respektive produkters särskilda funktioner. En sådant logiskt produktaggregat kan också fås att utföra funktioner som användaren annars skulle ha väldigt svårt att realisera genom att manuellt kombinera de nödvändiga produktfunktionerna. Det underlättar alltså användningen av systemet (byggt av flera olika produkter), som fungerar som om det vore en enda produkt. Projektet har genomförts tillsammans med David Sabaté Mogica. Vi har utvecklat ett system för produktaggregering baserat på Dynamic Host Client protocol (DHCP) och Service Location Protocol (SLP) för att identifiera tillgängliga fuktioner och Virtual Network Computing (VNC) för ”remote desktop control”. Systemet är byggt i ett laboratorienät. Avhandlingen fokuserar på hur identifiering av tillgängliga funktioner och tjänster genomförs och utvärderas. ”Remote desktop control” utvecklades och infördes separat och kommer att rapporteras separat. Ömsesidig identifiering av funktioner mellan två datorer har genomförts med ett program utvecklat speciellt för en PDA. Hittils sänder emellertid PDA’n bara ett DA-frågepaket med DHCP. Den ömsesidiga funktionsidentifieringen är dock testad och fungerar mellan två datorer vilket gav den nödvändiga grunden för programmeringen av PDA’n och för framtida utveckling av liknande program för mobiltelefoner.
43

Bird-inspired self-assembly of hollow nanoparticles

Yang, Zepeng 16 July 2020 (has links)
No description available.
44

Reflections on the Impact of a Library-Based PDA Service

Wallace, Rick L., Woodward, Nakia J. 01 January 2010 (has links)
No description available.
45

[en] POSITIONING INTEGRATED ENVIRONMENT FOR MILITARY OPERATIONS / [pt] AMBIENTE INTEGRADO PARA POSICIONAMENTO EM OPERAÇÕES MILITARES

GUSTAVO MOREIRA PIERRE 01 June 2005 (has links)
[pt] Com o crescimento tecnológico temos visto uma popularização crescente de equipamentos de localização por satélite (receptores GPS) e computadores de bolso (PDA) em diversas áreas: nos transportes aéreo, marítimo e terrestre, mapeamento e geoprocessamento, esporte e lazer. Onde podemos ver, como exemplo, praticantes de caminhadas adquirindo seus próprios receptores GPS. No meio militar, esta popularização também crescente, onde as Forças Armadas de diversos países tendem a adquirir cada vez mais equipamentos de posicionamento por satélite (receptores GPS) e testam equipamentos para interação com os mesmos. O foco deste trabalho a integração do receptor GPS e PDA visando sua utilização em operações militares, com intuito de obter respostas rápidas para um emprego mais eficiente e rápido de frações das tropas envolvidas. Este trabalho envolve a geração de arquivos legíveis aos PDA, a comunicação de receptores GPS com estes, bem como a visualização da informação fornecida por estes receptores de forma fácil e rápida. Abrange também uma comparação entre a utilização de mapas em duas diferentes representações raster e vetorial, possibilitando zoom e movimento da imagem em ambos, além da possibilidade de medir distâncias entre pontos do mapa na tela do PDA e inclusão, exclusão e alteração de observações diversas. Verificou-se a grande vantagem da utilização de imagens raster em relação utilização de imagens vetoriais no PDA para esta finalidade, e também algumas fragilidades do uso de PDA comuns em operações militares e com receptores GPS de usos gerais. / [en] With technological development, we have been witnessing a growing popularization of satellite-location equipment (GPS receivers) and pocket computers (PDA) in several areas: air, sea and earth transports, mapping and geoprocessing, sports and entertainment. We can see hikers, for example, acquiring their own GPS receivers. In the military environment, this popularization is also occurring: the Armed Forces in several countries are obtaining increasing numbers of GPS receivers and are testing equipment to interact with them. The purpose of this work is to integrate GPS receivers and PDAs, with the intention of employing them in military operations in order to obtain quick responses for a faster and more efficient use of fractions of involved troops. This work involves the generation of files readable by PDAs, the communication of GPS receivers with PDAs, and an easy and fast visualization of the information provided by the receivers. It also includes a comparison between the use of maps in two different representations, raster and vector, both allowing for zooming and movement of the image, as well as the possibility of measuring distances between points of the map in the PDA screen, and the inclusion, exclusion and alteration of several observations. The great advantage of using raster images instead of vector images in PDAs for this purpose was verified, as well as some disadvantages in the use of PDAs, common in military operations, with general-purpose GPS receivers.
46

Análise toxicológica por técnicas de triagem aplicada em amostras biológicas post-mortem de casos suspeitos de intoxicação provenientes de Instituto de Criminalítisca / Systematic toxicological analysis by screening techniques applied in pos-mortem biological samples of suspected cases of poisning from Institute of Forensic

Silva, Maria Augusta Alves 12 February 2014 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2015-04-23T13:12:37Z No. of bitstreams: 2 Dissertação - Maria Augusta Alves Silva - 2014.pdf: 3616508 bytes, checksum: ff3549d426c3e4da5a2e979383c5aa23 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-04-23T13:15:41Z (GMT) No. of bitstreams: 2 Dissertação - Maria Augusta Alves Silva - 2014.pdf: 3616508 bytes, checksum: ff3549d426c3e4da5a2e979383c5aa23 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-04-23T13:15:41Z (GMT). No. of bitstreams: 2 Dissertação - Maria Augusta Alves Silva - 2014.pdf: 3616508 bytes, checksum: ff3549d426c3e4da5a2e979383c5aa23 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2014-02-12 / The toxicological analyzes on various samples are extremely important and can be used for multiple purposes, such as monitoring of drug addicts, forensic analysis, doping control, therapeutic monitoring, analyses of environmental contaminants, etc. The objective of this study was to analyze post - mortem blood samples of the Instituto de Criminalística de Goiás (IC) by immunochromatography and systematic toxicological analysis HPLC - PDA to check the presence or absence of toxic agents. The chromatographic conditions of the method were: mobile phase monobasic potassium phosphate buffer pH 2.3 and acetonitrile, flow rate 1 ml / min, Lichrospher RP8 column, 5μm, 250 x 4.0 mm, scanning range 200-380 nm, the calibration standards were MPPH system, caffeine, benzene and histamine. It was used the database proposed by UVTOX Pragst et al (2001). As part of the partial validation the matrix effect was evaluated by liquid-liquid extraction of whole blood samples contaminated with 8 standards in known concentration. The whole blood samples were extracted at different pH values and analyzed by HPLC -PDA. Through the areas obtained from each standard, it was calculated the standardized factor matrix which showed a coefficient of variation less than 10 %. In order to compare two screening techniques for detection of drugs of abuse, post-mortem blood samples from the IC (n = 35) were also analyzed by immunochromatography, yielding 10 samples positive for amphetamine, 3 for benzoylecgonine and 1 for Δ9THC. The ATS by HPLC – PDA analyses showed only 1 sample positive for benzoylecgonine, 2 samples for amphetamines, and 3 benzodiazepines. In the other samples, no substance toxicological interest was detected. Both immunochromatography as systematic toxicological analysis proved useful tools in screening post-mortem blood. / As análises toxicológicas em diversas amostras são de extrema importância e podem ter várias finalidades, como por exemplo, o monitoramento de dependentes químicos, análises forense, controle de doping, monitoramento terapêutico, análise de contaminantes ambientais dentre outras. O objetivo deste trabalho foi analisar amostras de sangue post-mortem do Instituto de Criminalística de Goiás (IC) através de imunocromatografia e análise toxicológica sistemática por HPLC-PDA para a verificação da presença ou ausência de agentes tóxicos. As condições cromatográficas do método foram: fase móvel tampão fosfato de potássio monobásico pH 2,3 e acetonitrila, fluxo de 1 mL/min, coluna Lichrospher RP8, 5μm, 250 x 4,0mm, faixa de varredura de 200 a 380 nm. Os padrões de calibração utilizados foram MPPH, cafeína, benzeno e histamina. A base de dados utilizada foi a UVTOX proposta por Pragst e colaboradores (2001). Na validação parcial foi avaliado o efeito matriz através da extração líquido-líquido de amostras de sangue total contaminada com padrões de hidroclorotiazida, furosemida, flunitrazepam, flurazepam, amitriptilina, clordiazepóxido, nitrazepam e diazepam, na concentração de de 10 g/mL. As amostras de sangue total foram extraídas em diferentes valores de pH e analisadas por HPLC-PDA. Através das áreas obtidas de cada padrão, calculou-se o fator de matriz normalizado que apresentou coeficiente de variação inferior a 10%. Com o intuito de comparar duas técnicas de triagem para detecção de drogas de abuso, amostras de sangue post-mortem do IC (n=35) foram analisadas também por imunocromatografia, obtendo-se 10 amostras positivas para anfetamina, 3 para benzoilecgonina e 1 para Δ9THC. Por outro lado, na ATS por HPLC-PDA apenas 1 amostra foi positiva para benzoilecgonina, 2 anfetaminas, e outras 3 para benzodiazepínicos. Nas demais amostras não foi detectada nenhuma substância de interesse toxicológico. Tanto a imunocromatografia quanto a análise toxicológica sistemática se mostraram ferramentas úteis na triagem de sangue post-mortem.
47

Avaliação do potencial metabólico de linhagens de fungos isolados de uma espécie de alga marinha do gênero Sargassum / Evaluation of the metabolic potential of fungal lineages isolated from a species of marine algae of the Sargassum genus

Romminger, Stelamar 20 November 2008 (has links)
Os fungos são microrganismos amplamente dispersos, podendo ser encontrados em vegetais, animais, solo e ambientes aquáticos, participando do ciclo de elementos na natureza. Embora muitos papéis ecológicos tenham sido estudados e descritos para os fungos terrestres, a ecologia de fungos marinhos ainda é pouco conhecida. Assim, os oceanos, que representam aproximadamente metade da biodiversidade global, são uma fonte enorme e virtualmente inexplorada de microrganismos produtores de novos produtos naturais. O objetivo deste trabalho foi isolar linhagens de fungos derivados de uma espécie de alga marinha do gênero Sargassum, visando à avaliação do seu potencial para a produção de metabólitos secundários bioativos. Ao todo foram isoladas 58 linhagens, das quais 52 foram crescidas em meio de cultura líquido e, após a extração com solventes orgânicos, deram origem a 99 extratos. Tais extratos foram avaliados por ensaios de atividade biológica, cromatografia em camada delgada (CCD), ressonância magnética nuclear (RMN) e cromatografia líquida acoplada a detectores de arranjo de diodos, espalhamento de luz evaporativo e espectrômetro de massas (LC - PDA - ELSD - MS). A avaliação pelo ensaio antibiótico foi o que resultou no maior número de extratos ativos (n = 13), seguido dos ensaios enzimático (n = 8), citotóxico (n = 3) e anti-tuberculose (n = 1). O extrato AS Fub 39, que apresentou atividade antibiótica, foi selecionado para estudos adicionais. Este extrato foi purificado por HPLC, e o seu composto majoritário identificado como sendo o 8-metóxi-3,5-dimetilisocroman-6-ol. Posteriormente, a linhagem AS Fub 39 foi taxonomicamente identificada como pertencendo à espécie Penicillium steckii. / Fungi are widely disperse microorganisms, typically associated with plants, animals, soil and aquatic environments (fresh and sea water), participating in the elements cycling. Although many ecological roles have been described for terrestrial fungi, ecological studies of marine derived fungi are still scarce. Therefore, oceans, which represent approximately half of the global biodiversity, are a huge and virtually unexplored source of microorganisms producers of interesting metabolites. The aim of this study was to isolate fungal strains derived from a marine algae of the Sargassum genus, and the evaluation of their metabolical potential for the production of secondary metabolites. Overall, 58 strains were isolated, of which 52 were grown in liquid culture media and extracted with organic solvents, originating 99 crude extracts. These extracts were analyzed by bioassays, thin layer chromatography (TLC), nuclear magnetic resonance (NMR) and liquid chromatography coupled with a photo diode array, an evaporative light scattering, and a mass spectrometry detectors (LC - PDA - ELSD - MS). The evaluation with the antibiotic assay resulted in the largest number of active extracts (n = 13), followed by the enzymatic (n = 8), the cytotoxic (n = 3) and the antituberculosis (n = 1) assays. The crude extract AS Fub 39, which presented antibiotic activity, was selected for additional studies. This extract was purified by HPLC, and its major compound identified as the 8-methoxy-3,5-dimethylisocroman-6-ol. Later, the AS Fub 39 strain was taxonomically identified as Penicillium steckii.
48

Closure of patent ductus arteriosus in very preterm infants:potential role of paracetamol and consequences of current treatments

Härkin, P. (Pia) 06 November 2018 (has links)
Abstract The ductus arteriosus connects the pulmonary artery and the descending aorta in the foetus. In normal neonatal transition, the ductus closes soon after birth. If the duct remains significantly open after birth, it may complicate the recovery of a very preterm infant. Present treatments of patent ductus arteriosus (PDA) are either medical (ibuprofen or indomethacin) or surgical (ligation). However, these treatments can have serious side effects, especially in the most immature infants. This doctoral thesis studied the potential role of intravenous paracetamol for PDA treatment in very preterm infants born before 32 weeks of gestation. Consequences of the PDA treatments in an epidemiological birth cohort were also studied. In retrospective Study I stated that treatments of PDA decreased after the introduction of IV paracetamol for early pain management in preterm infants. Study II showed in a randomised clinical trial for the first time that paracetamol has a biological effect on the ductus arteriosus in preterm infants soon after birth. The ductus closed significantly earlier in the paracetamol group than in the placebo group. The epidemiological cohort Study III showed evidence that both medical and surgical treatment of PDA associated with severe bronchopulmonary dysplasia in infants born very preterm. Additionally, surgical PDA ligation was associated with increased risk of necrotising enterocolitis and intraventricular haemorrhage. Study IV showed that treatment of PDA was not associated with increased mortality, even in the most immature preterm infants born before 28 weeks of gestation. / Tiivistelmä Valtimotiehyt on sikiöaikana avoimena oleva suoni, joka yhdistää keuhkovaltimon laskevaan aorttaan ja ohjaa vähähappisen veren istukkaan. Yhdessä soikean aukon kanssa suoni takaa sikiön verenkierron normaalin toiminnan ennen keuhkojen avautumista. Mikäli valtimotiehyt jää syntymän jälkeen pitkittyneesti auki, muuttaa se keskosen verenkiertoa siten, että osa aortan verenkiertoa ohjautuu keuhkoverenkiertoon vaikeuttaen pienen keskosen toipumista. Nykyhoitoina käytetään joko lääkkeellistä (ibuprofeeni tai indometasiini) tai kirurgista sulkua. Lääkkeellinen hoito ei ole kovin tehokas kaikista epäkypsimmillä keskosilla ja hoitoihin liittyy vakaviakin sivuvaikutuksia. Väitöskirjassa tutkittiin parasetamolilääkityksen vaikutusta hyvin pienen keskosen avoimen valtimotiehyen sulkeutumiseen. Epidemiologisessa osiossa tutkittiin nykyhoitojen sivuvaikutuksia hyvin pienillä keskosilla. Osatyössä I todettiin, että avoimen valtimotiehyen hoidon tarve väheni merkittävästi sen jälkeen kun parasetamoli oli otettu käyttöön kivun hoidossa vastasyntyneiden teholla. Osatyö II oli satunnaistettu ja sokkoutettu hoitotutkimus, jossa todettiin alkuperäishavaintona, että parasetamolilla on biologinen vaikutus keskosen avoimeen valtimotiehyeen. Parasetamolia saaneilla keskosilla valtimotiehyt sulkeutui aikaisemmin kuin verrokeilla. Hoidolla ei todettu merkittäviä sivuvaikutuksia. Osatöissä III ja IV tutkittiin kaikkien vuosina 2005−2013 Suomessa syntyneiden hyvin pienten keskosten avoimen valtimotiehyen hoitoja. Lääkehoidolla (ibuprofeeni ja indometasiini) ja kirurgisella hoidolla todettiin olevan yhteys keskosen kroonisen keuhkotaudin (BPD) vaikeimpaan muotoon. Kirurgisella hoidolla oli yhteys keskosen vaikeaan suolitulehdukseen ja vaikeaan aivoverenvuotoon. Kuolleisuuden riskin ei kuitenkaan todettu lisääntyneen valtimotiehyen hoitoihin liittyen.
49

Implication du facteur développemental Lim1, un nouvel oncogène, dans le cancer du rein humain avancé / Involvement of the developmental factor Lim1, a new oncogene, in advanced human kidney cancer

Hamaidi, Imene 26 September 2017 (has links)
Le carcinome à cellules rénales claires métastatique (CCC) demeure résistant aux thérapies actuelles. Les travaux précédents ont montré des similitudes mécanistiques entre tumorigenèse et néphrogenèse. Parmi les cibles de la voie oncogénique Sonic Hedgehog-Gli, le facteur développemental Lim1 a été identifié comme un nouvel oncogène dans le CCC. Les études préliminaires suggèrent que Lim1 aurait un rôle dans l’invasion cellulaire. Aucun inhibiteur de Lim1 n’est disponible; l’ARN interférence reste l’outil le plus efficace et le plus spécifique pour l’extinction des gènes. Dans le but de développer un nouvel outil d’inhibition de Lim1 applicable en clinique, basée sur des siRNAs véhiculés par des systèmes nanométriques, une nouvelle génération de véhicules de siRNAs a été étudiée. Il s’agit de polymères diacétyléniques photo-polymérisables sous forme de nanofibres (PDA-Nf). Ces travaux démontrent le rôle invasif de Lim1 dans la dissémination métastatique et identifient les PDA-Nf comme un nouvel outil de délivrance de siRNAs très prometteur en clinique. L’avantage du ciblage de Lim1 avec cette approche, est l’absence de son expression à l’âge adulte. / Clear cell renal cell carcinoma (CCC) remains resistant to current therapies, despite the development of anti-angiogenic and the new immunotherapeutic approaches. Previous work of the laboratory has shown mechanistic similarities between tumorigenesis and nephrogenesis. Among the targets of the Sonic Hedgehog-Gli pathway which is found oncogenic in CCC, the developmental factor Lim1 has been identified as a new oncogene in CCC. Preliminary studies suggest that Lim1 would have a role in cell invasion. No Lim1 inhibitors are available; RNA interference remains the most effective and specific tool for gene silencing. In order to develop a new clinically applicable inhibition tool for Lim1, based on siRNAs carried by nanoparticles, a new generation of siRNA vehicles has been investigated. These are photo-polymerizable diacetylenic polymers in the form of nanofibers (PDA-Nf). These works demonstrate the invasive role of Lim1 in metastatic dissemination and identifies PDA-Nf as a new promising siRNA delivery tool in clinical practice. The advantage of targeting Lim1 with this nano-carrier approach is that Lim1 is not expressed in adulthood.
50

Avaliação do potencial metabólico de linhagens de fungos isolados de uma espécie de alga marinha do gênero Sargassum / Evaluation of the metabolic potential of fungal lineages isolated from a species of marine algae of the Sargassum genus

Stelamar Romminger 20 November 2008 (has links)
Os fungos são microrganismos amplamente dispersos, podendo ser encontrados em vegetais, animais, solo e ambientes aquáticos, participando do ciclo de elementos na natureza. Embora muitos papéis ecológicos tenham sido estudados e descritos para os fungos terrestres, a ecologia de fungos marinhos ainda é pouco conhecida. Assim, os oceanos, que representam aproximadamente metade da biodiversidade global, são uma fonte enorme e virtualmente inexplorada de microrganismos produtores de novos produtos naturais. O objetivo deste trabalho foi isolar linhagens de fungos derivados de uma espécie de alga marinha do gênero Sargassum, visando à avaliação do seu potencial para a produção de metabólitos secundários bioativos. Ao todo foram isoladas 58 linhagens, das quais 52 foram crescidas em meio de cultura líquido e, após a extração com solventes orgânicos, deram origem a 99 extratos. Tais extratos foram avaliados por ensaios de atividade biológica, cromatografia em camada delgada (CCD), ressonância magnética nuclear (RMN) e cromatografia líquida acoplada a detectores de arranjo de diodos, espalhamento de luz evaporativo e espectrômetro de massas (LC - PDA - ELSD - MS). A avaliação pelo ensaio antibiótico foi o que resultou no maior número de extratos ativos (n = 13), seguido dos ensaios enzimático (n = 8), citotóxico (n = 3) e anti-tuberculose (n = 1). O extrato AS Fub 39, que apresentou atividade antibiótica, foi selecionado para estudos adicionais. Este extrato foi purificado por HPLC, e o seu composto majoritário identificado como sendo o 8-metóxi-3,5-dimetilisocroman-6-ol. Posteriormente, a linhagem AS Fub 39 foi taxonomicamente identificada como pertencendo à espécie Penicillium steckii. / Fungi are widely disperse microorganisms, typically associated with plants, animals, soil and aquatic environments (fresh and sea water), participating in the elements cycling. Although many ecological roles have been described for terrestrial fungi, ecological studies of marine derived fungi are still scarce. Therefore, oceans, which represent approximately half of the global biodiversity, are a huge and virtually unexplored source of microorganisms producers of interesting metabolites. The aim of this study was to isolate fungal strains derived from a marine algae of the Sargassum genus, and the evaluation of their metabolical potential for the production of secondary metabolites. Overall, 58 strains were isolated, of which 52 were grown in liquid culture media and extracted with organic solvents, originating 99 crude extracts. These extracts were analyzed by bioassays, thin layer chromatography (TLC), nuclear magnetic resonance (NMR) and liquid chromatography coupled with a photo diode array, an evaporative light scattering, and a mass spectrometry detectors (LC - PDA - ELSD - MS). The evaluation with the antibiotic assay resulted in the largest number of active extracts (n = 13), followed by the enzymatic (n = 8), the cytotoxic (n = 3) and the antituberculosis (n = 1) assays. The crude extract AS Fub 39, which presented antibiotic activity, was selected for additional studies. This extract was purified by HPLC, and its major compound identified as the 8-methoxy-3,5-dimethylisocroman-6-ol. Later, the AS Fub 39 strain was taxonomically identified as Penicillium steckii.

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