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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.
31

Characterizing the Syphilis-Causing Treponema pallidum ssp. pallidum Proteome Using Complementary Mass Spectrometry

24 September 2019 (has links)
Yes / Background. The spirochete bacterium Treponema pallidum ssp. pallidum is the etiological agent of syphilis, a chronic multistage disease. Little is known about the global T. pallidum proteome, therefore mass spectrometry studies are needed to bring insights into pathogenicity and protein expression profiles during infection. Methodology/Principal Findings. To better understand the T. pallidum proteome profile during infection, we studied T. pallidum ssp. pallidum DAL-1 strain bacteria isolated from rabbits using complementary mass spectrometry techniques, including multidimensional peptide separation and protein identification via matrix-assisted laser desorption ionization-time of flight (MALDI-TOF/TOF) and electrospray ionization (ESI-LTQ-Orbitrap) tandem mass spectrometry. A total of 6033 peptides were detected, corresponding to 557 unique T. pallidum proteins at a high level of confidence, representing 54% of the predicted proteome. A previous gel-based T. pallidum MS proteome study detected 58 of these proteins. One hundred fourteen of the detected proteins were previously annotated as hypothetical or uncharacterized proteins; this is the first account of 106 of these proteins at the protein level. Detected proteins were characterized according to their predicted biological function and localization; half were allocated into a wide range of functional categories. Proteins annotated as potential membrane proteins and proteins with unclear functional annotations were subjected to an additional bioinformatics pipeline analysis to facilitate further characterization. A total of 116 potential membrane proteins were identified, of which 16 have evidence supporting outer membrane localization. We found 8/12 proteins related to the paralogous tpr gene family: TprB, TprC/D, TprE, TprG, TprH, TprI and TprJ. Protein abundance was semi-quantified using label-free spectral counting methods. A low correlation (r = 0.26) was found between previous microarray signal data and protein abundance. Conclusions. This is the most comprehensive description of the global T. pallidum proteome to date. These data provide valuable insights into in vivo T. pallidum protein expression, paving the way for improved understanding of the pathogenicity of this enigmatic organism. / This work was supported by the grants from the Flanders Research Foundation, SOFI-B Grant to CRK, http://www.fwo.be/, a Public Health Service Grant from the National Institutes of Health to CEC, (grant # AI-051334), https://www.nih.gov/ and a grant from the Grant Agency of the Czech Republic to DS and MS (P302/12/0574, GP14-29596P), https:// gacr.cz/.
32

Uso de probiótico durante o transporte de juvenis de tambaqui (Colossoma macropomum) em sistema fechado

Ferreira, Celma Maria 10 March 2014 (has links)
Submitted by Simone Souza (simonecgsouza@hotmail.com) on 2017-08-21T13:59:05Z No. of bitstreams: 1 DISS_2014_Celma Maria Ferreira.pdf: 2069185 bytes, checksum: 3327660ede858ab91f20c4f9da62e4de (MD5) / Approved for entry into archive by Jordan (jordanbiblio@gmail.com) on 2017-08-24T14:44:49Z (GMT) No. of bitstreams: 1 DISS_2014_Celma Maria Ferreira.pdf: 2069185 bytes, checksum: 3327660ede858ab91f20c4f9da62e4de (MD5) / Made available in DSpace on 2017-08-24T14:44:49Z (GMT). No. of bitstreams: 1 DISS_2014_Celma Maria Ferreira.pdf: 2069185 bytes, checksum: 3327660ede858ab91f20c4f9da62e4de (MD5) Previous issue date: 2014-03-10 / PROPEQ-UFMT / Objetivou-se estudar se o uso de probiótico a base de Bacillus spp, veiculado na ração e dissolvido em água, é capaz de alterar as características histomorfométricas da mucosa intestinal de tambaqui e minimizar as respostas de estresse desta espécie durante o procedimento de transporte. Um total de 510 juvenis de tambaqui (peso e comprimento total médio inicial de 83,26 ± 28,14 g e 17,39 ± 1,90 cm, respectivamente) foi distribuído em três tanques de alvenaria. Durante 60 dias, os peixes de dois tanques foram alimentados com ração comercial e os peixes do terceiro tanque com ração comercial suplementada com probiótico. Após este período, os peixes de cada tanque foram divididos em sacos plásticos e transportados por 4 horas de acordo com os seguintes tratamentos: T1: alimentação com ração comercial (controle); T2: alimentação com ração comercial e probiótico adicionado na água durante o transporte (20 mg/L); T3: alimentação com ração comercial suplementada com probiótico (1,0 g/kg de ração). Antes do transporte (basal), 24 e 96 horas após o transporte, oito peixes de cada tratamento foram submetidos à eutanásia e o intestino retirado para pesagem e mensuração do comprimento para avaliação da relação comprimento corporal/intestino. Em seguida, foi realizada coleta da porção anterior e posterior do intestino, para avaliação das características morfo-histológicas da mucosa intestinal (altura e comprimento das vilosidades). Nestes mesmos tempos de amostragem e imediatamente após transporte (chegada)ocorreram as coletas de sangue para avaliação de parâmetros metabólicos, hematológicos, iônicos e imunológicos. Os resultados foram analisados por ANOVA usando o software SAS e os dados expressos em médias comparadas pelo teste de Tukey, com 5% de significância. A suplementação com probiótico (Bacillus spp.) não exerceu efeito no peso, peso relativo, altura e comprimento das vilosidades do intestino do tambaqui submetido ao transporte. Além disso, as respostas de estresse durante este procedimento foram similares entre os tratamentos testados, indicando que o probiótico não foi eficiente em suprimir as respostas de estresse e melhorar o sistema imunológico inato no tambaqui. / The aim of this study was to evaluate the intestinal mucosal integrity and the effectiveness of addition of a probiotic as a potential stress reducer during the transport of tambaqui juveniles. In a completely randomized design with three treatments and seven replications, a control treatment (fish fed a commercial diet without probiotic) with was compared with two other treatments involving the use of a commercial probiotic incorporated into the diet or in the transport water. A total of 510 juvenile tambaqui (83.26 ± 28.14 g and 17.39 ± 1.90 cm) were distributed into three cement tanks. For 60 days, fish from the two tanks were fed a commercial diet, and the fish from the third tank received a commercial diet supplemented with a probiotic. After this period, the fish from each tank were divided into plastic bags and transported for four hours, receiving the following treatments: T1: commercial diet (control); T2: commercial diet and probiotic dissolved in the transport water (20 mg/L); T3: commercial diet supplemented with probiotic (1.0 g/kg diet). Before transport (baseline), and 24 and 96 hours after transport, fish from each treatment were euthanized and their intestine was removed for morphological and histological evaluation of the intestinal mucosa. In these same sampling times and immediately after transport, blood was collected to evaluate metabolic, hematologic, immunologic, and ionic parameters. The results were analyzed by ANOVA using the SAS software and data were expressed as means compared by Tukey’s test at 5% significance. In all treatments, the intestine length increased with increase in thefish size. Supplementation with probiotic (Bacillus spp.) had no effect on weight (g), relative weight (%), villus height and villus length of tambaqui challenged with transport. The stress response of the tambaqui fish was similar among the tested treatments, indicating that the probiotic used was not efficient in suppressing stress during transportation.
33

Resposta de seis variedades de cana-de-açúcar a doses de potássio no cerrado de Roraima

Hélio de Oliveira Alves Júnior 26 March 2009 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A seleção de variedades produtivas, responsivas a adubação e adaptadas às condições edafoclimáticas local é essencial para estabelecer o cultivo sustentável da cana-de-açúcar nos solos do cerrado de Roraima. Para tanto, esta pesquisa objetivou estudar a resposta de seis variedades de cana-de-açúcar a doses crescentes de potássio no cerrado de Roraima. O trabalho foi realizado em condições de campo e conduzido no Centro de Ciências Agrárias da Universidade Federal de Roraima, com clima Awi em Latossolo Amarelo. O delineamento experimental foi de blocos casualizados, em esquema fatorial de parcelas subdivididas, onde cada bloco foi constituído por cinco parcelas formadas pelas doses de potássio (0, 80, 160, 240 e 320 Kg ha-1 de K2O) e seis subparcelas pelas variedades (RB72454, SP81-3250, SP79-1011, SP801816, RB867515 e RB855536), com quatro repetições / Selections for productive varieties, responsive to fertilization and adapted to local edafoclimatic conditions is essential for establishment of sustainable crop of sugarcane in savanna soils of Roraima. In this way, this research intended to study the performance of six sugar-cane varieties to increasing doses of potassium in the savanna of Roraima. This research was conducted in field conditions in the Centro de Ciências Agrárias, at Universidade Federal de Roraima, under Awi climate in a yellow latossol. The experimental design was completely randomized blocks, under a factorial scheme of split-plot, where each block consisted of five plots with doses of potassium (0, 80, 160, 240 and 320 Kg ha-1) and six subplots with varieties (RB72454, SP81-3250, SP79-1011, SP801816, RB867515 and RB855536) with four replicates
34

Identificação de isolados de Trichoderma spp. utilizando marcadores do tipo RAPD e DNA Barcode / Identification of Trichoderma spp. strains using RAPD markers and DNA Barcode

SANTOS, Patrícia Ribeiro dos 03 March 2010 (has links)
Made available in DSpace on 2014-07-29T15:16:32Z (GMT). No. of bitstreams: 1 Patricia Ribeiro dos Santos.pdf: 1037396 bytes, checksum: e99d81a176db1d0496423b4ece2cefbd (MD5) Previous issue date: 2010-03-03 / Biological control is a natural process that regulates the number of individuals existing in a population, by the action of another individual called "natural enemies or biological control agent (parasitoids, predators and pathogens), causing biotic mortality. Fungi that act as antagonists of phytopathogenic fungi have been used to control the disease, and 90% of these applications have been made using strains of fungi of the genus Trichoderma. The genus Trichoderma (Ascomycetes) Hypocreales, belonging to the class and brings Hifomicetos species that are among the soil fungi most commonly found in nature. There are several problems related to the nomenclature of individuals of this gender. Molecular tools such as markers and DNA Barcode has been used in identification of Trichoderma but also another fungi. The objective of this work was to identify isolates of Trichoderma spp. using only molecular tools. Analysis using markers make possible the observation of the high degree of genetic variability between these individuals, but proved problematic when the sample size was increased. The identification of individuals using DNA Barcode was possible only for a few individuals who show the need for the high quality sequences obtained by sequencing. The phylogenetic analysis was extremely difficult because is time consuming and required much time to perform the analysis. However by Neighbor-joining analysis was observed that when using databases such as BLAST error rate in identifying these species is high due to deposition of sequences of isolates incorrectly identified. / Controle biológico é um processo natural, que regula o número de indivíduos existentes em uma população, pela ação de outro indivíduo chamado de inimigo natural ou agente de controle biológico (parasitóides, predadores e patógenos), causando mortalidade biótica. Fungos que atuam como antagonistas de fungos fitopatogênicos têm sido usados para controlar a doença, sendo que 90% dessas aplicações tem sido feitas utilizando-se linhagens de fungos do gênero Trichoderma. O gênero Trichoderma (Ascomycetes), ordem Hypocreales, pertencente à classe dos hifomicetos e reúne espécies que se encontram entre os fungos de solo mais comumente encontrados na natureza. Vários são o problemas relacionados à nomeclatura de indivíduos desses gênero. Ferramentas moleculares, como marcadores e DNA Barcode tem sido usadas na identificação não só de Trichoderma mas também de outro fungos. Esses trabalho teve como objetivo identificar isolados de Trichoderma spp. Utilizando somente ferramentas moleculares. A análise utilizando marcadores RAPD posiibilitaram uma observação do alto grau de variabilidade genética existente entre esses indivíduos, ma se mostrou problemática quando o número amostral foi aumentado. A identificação de indivíduos utilizando DNA Barcode só foi possível para poucos indivíduos o que demonstra a necessidade de que as sequências obtidas sejam de alta qualidade. A análise filogenética se mostrou extremamente difícil, devido a demanda de tempo necessária para a realização das análises. Entretanto através da análise de Neighbor-joining foi possível observar que quando se utiliza bancos de dados como o BLAST a taxa de erro na identificação dessas espécies é grande devido ao depósito de sequências de isolados incorretamente identificados.
35

Limonóides e protolimonóides de Trichilia elegans ssp. Elegans A. Juss. (Meliaceae) / Limonoids and protolimonoids of Trichilia elegans ssp. Elegans A. Juss. (Meliaceae)

Garcez, Fernanda Rodrigues 11 June 1997 (has links)
o presente trabalho teve como objetivo realizar o estudo químico das sementes de Trichilia elegans ssp. Elegans A. Juss. (coletadas no município de Corumbá, MS), visando o isolamento e identificação ou elucidação estrutural dos seus metabólitos secundários, particularmente limonóides. Da fase diclorometânica, obtida de uma partição efetuada com o extrato etanólico das sementes, foram isoladas, através de técnicas cromatográficas de separação (cromatografia em colunas de sílica gel, de Sephadex LH 20 e CLAE em fase reversa), dezoito substâncias, compreendendo: dois protolimonóides, onze limonóides com esqueleto do tipo obacunol (abertura dos anéis A e D), quatro com esqueleto do tipo ivorensato de metila (abertura dos anéis A, B e D) e 3β-O-β-D-glicopiranosilsitosterol. Todas as substâncias são inéditas, com exceção do esteróide glicosilado e de dois limonóides com esqueleto do tipo obacunol (kihadaninas A e B). As determinações estruturais foram efetuadas com base em dados espectroscópicos de RMN 1H e 13C, incluindo experimentos bidimensionais (COSY 1H-1H, COSY 1H-13C, HMQC, NOESY e HMBC); a partir de informações obtidas dos espectros de massas e na região do IV e através de dados de difração de raios-X. Quatro dos limonóides obtidos foram submetidos a um ensaio biológico de atividade antitumoral, utilizando-se linhagens mutantes de Saccharomyces cerevisiae, porém, mostraram-se inativos. / The present work describes the isolation and identification or structural elucidation of the chemical constituents of the seeds of Trichilia elegans ssp. Elegans A. Juss., collected in Corumbá, MS. From the dichloromethane solubles, obtained from partition of the ethanolic extract from the seeds, eighteen substances have been isolated, after a combination of column and flash chromatography on silica gel, gel filtration and reversed phase HPLC separations. The isolated substances have been characterized as two new protolimonoids, nine new obacunol- and four new methyl ivorensate-type limonoids, in addition to two known limonoids belonging to the obacunol group (kihadanins A and B) and 3-O-&#946-D-glucopyranosyl-sitosterol. The structures of these compounds have been established on the basis of 1D (1H, 13C) and 2D (1H-1H and 1H-13C COSY, HMQC, HMBC and NOESY) NMR spectroscopic techniques, IR and mass spectral data and X-ray crystallographic analyses. Four of the isolated limonoids have been tested against DNA reparr deficient mutants of Saccharomyces cerevisiae but, nevertheless, shown to be inactive.
36

Treeline dynamics in short and long term perspectives : observational and historical evidence from the southern Swedish Scandes

Öberg, Lisa January 2013 (has links)
Treelines in high-mountain regions are constrained by heat deficiency, although the working mechanisms are still not entirely understood. Observational and paleoecological studies on treeline performance may contribute to increased understanding of the treeline phenomenon in general. The present thesis addresses elevational shifts of alpine treelines in the Swedish Scandes. By various analytical tools, the studies embrace widely different temporal scales. The concept treeline refers to the elevation (m a.s.l.) at a specific site of the upper individual tree of a certain tree species, at least 2 m tall. All the principal tree species in the Scandes are concerned, i.e. mountain birch (Betula pubescens ssp. czerepanovii), Norway spruce (Picea abies) and Scots pine (Pinus sylvestris). Paper I deals with regional treeline dynamics at more than 100 sites over the past 100 years. Concurrent with temperature rise by c. 1.4 °C over the same period, maximum treeline advances of all species amount to about 200 m. Thus, under ideal conditions, treelines respond in close equilibrium with air temperature evolution. However, over most parts of the landscape, treeline upshifts have been much smaller than 200 m, which relates to the combined action of geomorphology, wind, snow distribution and soil depth. After 1975, the birch has lost its role as the most rapidly advancing tree species, being superseded by pine and spruce. Paper II is a short-term (2005/2007-2010/2011) study of mountain birch treeline performance along a regional maritimity-continentality gradient. Upshift by 3.0 yr-1 in the maritime part of the gradient contrasts to retreat by 0.4 m yr-1 in the continental part. In the latter area, earlier and more complete melting of late-lying snow patches has seemingly progressed to a state when soil drought sets back the vigour of existing birches and precludes sexual regeneration and upslope advance of the treeline. In the maritime area, extensive and deep snow packs still exist above the treeline and constrain its position, although some release is taking place in the current warm climate. Paper III explores treeline change by phenotypic transformation of old-established stunted and prostrate spruce individuals (krummholz) growing high above the treeline and is based on analyses of radiocarbon-dated megafossils, preserved in the soil underneath clonal groups of spruce. Living spruce clones, which in some cases may date back to the early Holocene (9500 cal. yr BP), suggests that spruce immigrated from “cryptic” ice age refugia much closer to Scandinavia than conventionally thought. As the krummholz form presupposes open and windy habitats, it is inferred that permanently open spots prevailed in the high-mountain landscape even during periods when treelines in general were much higher than today. Paper IV reports radiocarbon dates of wood samples, retrieved from newly exposed glacier forefields at three main sites, located high above the modern treelines and embracing the entire Swedish Scandes. It appears that pine colonized early emerging nunataks already during the Late Glacial. Around 9600-9500 cal. yr BP a first massive wave of tree establishment, birch and pine, took place in “empty” glacier cirques. Both species grew 400-600 m above their present day treeline position and accordingly, the summer temperatures may have been 3.5 °C warmer than present (uncorrected for land uplift). During the entire interval 9600 to 4400 cal. yr BP, birch prospered 100-150 m above the uppermost pines. In response to Neoglacial cooling, treelines of both birch and pine descended until their final disappearance from the record 4400 and 5900 cal. yr BP, respectively. Thereafter, these habitats experienced increased snow accumulation and glacier inception. / Avhandlingen belyser förskjutningar i olika tidsskalor av den alpina trädgränsens läge i de svenska Skanderna. Trädgränsen definieras som den högsta nivån (m ö.h.) för minst 2 m höga individer av en viss art i en definierad del av en fjällsluttning. Avhandlingen består av fyra separata uppsatser, publicerade i olika välrenommerade vetenskapliga tidskrifter.  I Paper I analyseras förändringar av trädgränserna för fjällens vanligaste trädarter, fjällbjörk, gran och tall (Betula pubescens ssp. czerepanovii, Picea abies och Pinus sylvestris) mellan 1915 och 2007. Undersökningen omfattar ett 8000 km2 stort, naturgeografiskt heterogent område, med mer än 100 lokaler. De maximala trädgränsförskjutningarna för samtliga trädarter uppgår till omkring 200 m. Resultaten motsvarar de trädgränsförskjutningar som teoretiskt kan förutsägas utifrån den temperaturhöjning med cirka 1,4 °C som skett under samma tidsperiod, förutsatt ideala förhållanden. För större delen av området råder emellertid andra, icke-ideala förhållanden, varför trädgränsernas uppflyttning i allmänhet blivit avsevärt mindre än 200 m. Den främsta anledningen till detta är lokala topoklimatiska begränsningar, d.v.s. kombinerade effekter av geomorfologi, vind, snöfördelning, jorddjup, etc., som i stora delar av det starkt brutna fjällandskapet mer eller mindre effektivt hindrar träden från att nå sina potentiellt högst belägna växtplatser betingade av temperaturen. Efter 1975 har björken förlorat sin roll som arten med den snabbast expanderande trädgränsen. I stället har tall och gran avancerat med större hastighet. Det innebär att även om klimatets uppvärmning fortsätter, så kommer det subalpina björkbältet att expandera i avsevärt mindre omfattning än vad som ofta förebådats. Möjligtvis kommer det att ersättas av tall. Paper II behandlar björkens trädgränsdynamik under perioden 2005/2007-2010/2011 längs en regional klimatgradient med avseende på maritimitet/kontientalitet. Trädgränsen har under den aktuella perioden avancerat 3,0 m/år i den maritimt präglade delen av gradienten, vilket kontrasterar signifikant mot en sänkning med 0,4 m/år i området med mer kontinentalt klimat. Skillnaderna diskuteras i termer av klimatförändringens varierande effekter på snötäckets utbredning och varaktighet och dess inverkan på markfuktigheten. En allt tidigare total utsmältning av snölegorna i de kontinentala områdena har av allt att döma resulterat i vattenbrist under sommaren. Torka medför reducerad vitalitet för existerande björkar och förhindrar både sexuell förökning och uppflyttning av trädgränsen. I de maritima delarna kvarligger alltjämt mycket snö under en stor del av sommaren. Trädgränsens position har därför kunnat bibehållas eller flyttas upp. Vissa omständigheter tyder på att trädgränsens stigning i högre grad har varit baserad på fröföryngring efter 1975, jämfört med perioden 1915-1975. Utgångspunkten för Paper III är erfarenheter från Paper I, som visar att trädgränsens uppflyttning för gran och björk huvudsakligen är resultatet av ökad höjdtillväxt av äldre, i vissa fall flertusenåriga, mer eller mindre buskformiga individer (krummholz), som vuxit på nivåer långt ovanför trädgränsen. Som ett svar på de senaste hundra årens varmare klimat har dessa antagit trädform, varigenom trädgränsen höjts. För en fördjupad förståelse av den här mekanismen har megafossil, d.v.s. grova vedrester bevarade i marken under gamla grankloner i trädgränsekotonen, 14C-daterats. Resultaten tyder på att granar i exponerad fjällmiljö kan uppnå i det närmaste ”evigt” liv genom sin förmåga till vegetativ förökning och möjligheten att växla mellan busk- och trädform i takt med klimatets växlingar. Vissa nu levande kloner existerade av allt att döma redan för 9500 år sedan. Den nu dokumenterat tidiga förekomsten av gran, bekräftar den på senare tid allt tydligare bilden av granen som en tidig invandrare till fjällkedjan. Möjligtvis har granen ”övervintrat” den senaste istiden närmare Skandinavien än vad som till helt nyligen varit den gängse uppfattningen. Paper IV behandlar en för Skandinavien ny metod för historisk trädgränsrekonstruktion. I uppsatsen analyseras 14C-dateringar av totalt 78 större veddelar (megafossil) som nyligen exponerats i anslutning till smältande glaciäris och ”perenna” snölegor i tre huvudområden, Helags-Sylarna, Tärna och Abisko, högt ovanför dagens trädgräns. Det framkommer att tall (Pinus sylvestris) koloniserade tidigt framsmälta nunatakker redan under senglacial tid. För omkring 9600-9500 år sedan inträffade en första massiv våg av björk- och talletablering i isfria glaciärnischer. Båda arterna växte 400-600 m ovanför sina nuvarande trädgränspositioner, i ett klimat som kan ha varit 3,5 °C varmare än idag. Under intervallet 9600 till 4400 BP uppträdde björken i ett 100-150 m brett bälte ovanför de översta tallarna. Som ett svar på klimatets successiva avkylning under senare delen av Holocen sänktes både björkens och tallens trädgränser i de aktuella miljöerna, till dess de för 4400 respektive 5900 år sedan helt försvann från lokaler där glaciärer och perenna snöfält började bildas. De analyserade trädresterna, som länge bevarats av glaciäris och perenn snö representerar en period med ett klimat långt varmare än under det senaste århundradet. Med denna analogi från det förflutna kan det därför antas att i en framtid där sommartemperaturerna rent hypotetiskt är 3,5 °C högre än i nutiden, skulle trädgränserna lokalt kunna flyttas upp med ungefär 600 m.
37

Epidemiological investigation on the occurrence of Mycobacterium avium subspecies paratuberculosis in different matrices from cattle and zoo animals by IS900 polymerase chain reaction assays / Epidemiologische Untersuchung zum Vorkommen von Mycobacterium avium subspecies paratuberculosis in verschiedenen Matrices von Rindern und Zootieren mittels IS900 PCR-Verfahren

Münster, Pia 16 May 2012 (has links)
No description available.
38

Avaliação de queijo de coalho produzido com bactérias láticas endógenas

Viana, Arão Cardoso 17 February 2009 (has links)
Submitted by Glauber Assunção Moreira (glauber.a.moreira@gmail.com) on 2018-08-20T17:48:24Z No. of bitstreams: 2 versão 8 arão.pdf: 389258 bytes, checksum: a2429e8f15ea08ff3f880538dc4b37d0 (MD5) Errata Arão Cardoso Viana.pdf: 4889 bytes, checksum: 909aee0b82dd5ac49d90de1c7ce75506 (MD5) / Approved for entry into archive by Setor de Periódicos (per_macedocosta@ufba.br) on 2018-08-21T14:59:01Z (GMT) No. of bitstreams: 2 versão 8 arão.pdf: 389258 bytes, checksum: a2429e8f15ea08ff3f880538dc4b37d0 (MD5) Errata Arão Cardoso Viana.pdf: 4889 bytes, checksum: 909aee0b82dd5ac49d90de1c7ce75506 (MD5) / Made available in DSpace on 2018-08-21T14:59:01Z (GMT). No. of bitstreams: 2 versão 8 arão.pdf: 389258 bytes, checksum: a2429e8f15ea08ff3f880538dc4b37d0 (MD5) Errata Arão Cardoso Viana.pdf: 4889 bytes, checksum: 909aee0b82dd5ac49d90de1c7ce75506 (MD5) / RESUMO A utilização de leite pasteurizado, para processamento de queijo coalho, garante a qualidade do produto sob o aspecto microbiológico. Neste caso, é necessária a adição de culturas láticas, que irão conferir ao produto características sensoriais diferenciadas. Este trabalho teve como objetivo avaliar a qualidade de queijo de coalho produzido com adição de diferentes culturas láticas endógenas utilizando a Análise Descritiva Quantitativa (ADQ), teste de aceitabilidade e análise de alguns parâmetros físico-químicos. Foram utilizadas três culturas láticas: LA-02 (Lactobacillus acidofilus); RE-02 (Lactococcus ssp) e Blend (Lactococcus ssp + Lactobacillus acidofilus). A equipe da ADQ foi composta por 11 julgadores treinados. No teste de aceitabilidade utilizou-se 50 consumidores previamente selecionados por questionário. Os parâmetros físico-químicos avaliados foram: umidade, cinzas, gordura em base seca, proteínas, pH, acidez e cloretos. A aceitabilidade dos queijos produzidos pelo LA-02 e Blend foram maiores para os atributos sabor, 7.38 e 6.92 e, respectivamente. Pela ADQ foram levantados 13 termos descritores para queijo coalho. A amostra Blend foi caracterizada pela cor amarela, firmeza, aroma típico de queijo de coalho, sabor típico de queijo de coalho, elasticidade e mastigabilidade. O queijo produzido com LA-02 foi caracterizado pelo sabor ácido, homogeneidade e maciez. As três amostras avaliadas apresentaram valores de umidade e gordura dentro das especificações exigidas pela legislação vigente. As culturas LA-02 e Blend foram as que melhor desenvolveram as características típicas de queijo coalho. / Abstract The utilization of pasteurized Milk to coalho cheese process guarantees the product quality on the microbiological aspect. In this case, it needs the addition of lactic culture and so that, the product comes out with differing sensorial characteristics. The objective of this work was to evaluate the coalho cheese quality, produced by adding lactic culture endogen using coalho cheese. The objective of this work was to evaluate the coalho cheese quality produced by adding endogen lactic culture utilizing the Quantities Descriptive Analysis (QDA), test of acceptability and analysis of some physical-chemical parameters. It was utilized three lactic cultures: LA-02 (Lactobacillus acidophilus); RE-02 (Lactococcus ssp) and Blend (Lactococcus ssp + Lactobacillus acidophilus). The team of QDA was with eleven people to judge it. The acceptability utilized fifty consumers previously selected by a questionnaire. The physical-chemical parameters evaluated were: humidity, ashes, base dried fat, proteins, ph, acidity and cloret. The cheese acceptability produced by LA-02 and Blend presented the highest results to the attributes flavor, 7.38 and 6.92, respectively. By the QDA were considered 13 describing terms to coalho cheese. The display of Blend was characterized by its yellow color, hardness, typical coalho cheese smell, typical coalho cheese flavor, consistency and chewing. The cheese produced by LA-02 was characterized by its acid flavor, homogeneity and softness. The three displays evaluated presented values of humidity and fat according to the legislation exigency. The LA-02 and Blend cultures were the ones which better developed the coalho cheese characteristics.
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Caractérisation fonctionnelle de petites protéines sécrétées chez les champignons lignolytiques / Characterization of small proteins by lignolytic fungi

Valette, Nicolas 06 December 2017 (has links)
Durant ces dernières décennies, les systèmes enzymatiques de dégradation du bois sécrétés par les champignons ont fait l’objet de nombreuses études aboutissant à la caractérisation fonctionnelle et biochimique des enzymes extracellulaires majeures agissant directement sur le polymère. Cependant, les systèmes annexes associés au processus de dégradation n’ont à l’heure actuelle été que peu étudiés. En particulier, les systèmes de détoxication et de réponses des champignons au stress généré par le processus de dégradation ainsi que les mécanismes lui permettant de croître dans cet environnement hostile sont encore peu connus. Ce stress est majoritairement dû à la présence de radicaux et d’extractibles. Les extractibles sont des molécules issues du métabolisme secondaire de l’arbre qui sont synthétisés pour augmenter la durabilité du bois face aux attaques biotiques et abiotiques. Une analyse transcriptomique réalisée au laboratoire a mis en évidence la surexpression de gènes codant des petites protéines sécrétées (SSP) chez Phanerochaete chrysosporium lors d’une culture en présence d’extractibles de chêne. La fonction de ce type de protéines chez les champignons lignolytiques est inconnue. Mon projet de thèse a porté sur la caractérisation d’une de ces SSP (SSP1). Les résultats obtenus ont révélé des propriétés biochimiques atypiques pour cette protéine qui est capable de former une structure fibrillaire, notamment grâce à la présence d’un domaine C-terminal riche en alanine et glycine. De plus, nous avons pu montrer que cette protéine présentait une activité β-glucuronidase in vitro, qui est dépendante de son état d’oligomérisation. Une approche physiologique a également été abordée grâce à l’obtention de mutants knock-out de SSP de Podospora anserina. La caractérisation de ces mutants a montré un défaut de croissance en condition de stress oxydant et en présence de molécules perturbant l’intégrité de la paroi cellulaire. Enfin, une analyse in silico des orthologues de SSP1 a montré la présence de ce gène dans les génomes d’organismes saprophytes, ectomycorhiziens ou pathogènes suggérant un rôle indirect de cette protéine dans les processus de dégradation du bois, probablement en lien avec la gestion du stress associé / During the last decades, the enzymatic systems involved in wood degradation have been intensively studied in fungi. This has led to functional and biochemical characterization of the main extracellular enzymes that are involved in the process. However, other systems associated to the degradation mechanisms have been poorly studied. In particular, the detoxification and stress response pathways allowing the fungus to grow in and resist the toxic conditions that are associated to the degradative process are still unknown. This stress is mostly due to the presence of radicals and extractives. Extractives are putative toxic compounds produced as secondary metabolites in tree to enhance wood durability against biotic and abiotic attacks. A transcriptomic analysis performed in the laboratory highlighted the up-regulation of genes coding for small secreted proteins (SSP) in Phanerochaete chrysosporium in presence of oak extractives. The functions of these SSP are unknown in lignolytic fungi. My PhD project was focused on the characterization of one of these SSP (namely SSP1) of P. chrysosporium. The biochemical data revealed atypical features for SSP1. Indeed, it is able to form fibrilar structure, thanks to an alanine-rich and glycine-rich C-terminal domain. Moreover, we have shown that this protein exhibits β-glucuronidase activity in vitro which is dependent on its oligomerization state. Physiological data were obtained thanks to the obtention of SSP knock-out mutants in Podospora anserina. These mutants have growth defect in oxidizing stress condition and in presence of cell wall-disruptive compounds. Finally, the in silico analysis of SSP1 orthologues revealed the presence of this gene in genomes of saprophytic, ectomycorrhizal or pathogenic fungi, suggesting an indirect role of this protein in wood degradation processes, probably linked to the associated stress
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Limonóides e protolimonóides de Trichilia elegans ssp. Elegans A. Juss. (Meliaceae) / Limonoids and protolimonoids of Trichilia elegans ssp. Elegans A. Juss. (Meliaceae)

Fernanda Rodrigues Garcez 11 June 1997 (has links)
o presente trabalho teve como objetivo realizar o estudo químico das sementes de Trichilia elegans ssp. Elegans A. Juss. (coletadas no município de Corumbá, MS), visando o isolamento e identificação ou elucidação estrutural dos seus metabólitos secundários, particularmente limonóides. Da fase diclorometânica, obtida de uma partição efetuada com o extrato etanólico das sementes, foram isoladas, através de técnicas cromatográficas de separação (cromatografia em colunas de sílica gel, de Sephadex LH 20 e CLAE em fase reversa), dezoito substâncias, compreendendo: dois protolimonóides, onze limonóides com esqueleto do tipo obacunol (abertura dos anéis A e D), quatro com esqueleto do tipo ivorensato de metila (abertura dos anéis A, B e D) e 3β-O-β-D-glicopiranosilsitosterol. Todas as substâncias são inéditas, com exceção do esteróide glicosilado e de dois limonóides com esqueleto do tipo obacunol (kihadaninas A e B). As determinações estruturais foram efetuadas com base em dados espectroscópicos de RMN 1H e 13C, incluindo experimentos bidimensionais (COSY 1H-1H, COSY 1H-13C, HMQC, NOESY e HMBC); a partir de informações obtidas dos espectros de massas e na região do IV e através de dados de difração de raios-X. Quatro dos limonóides obtidos foram submetidos a um ensaio biológico de atividade antitumoral, utilizando-se linhagens mutantes de Saccharomyces cerevisiae, porém, mostraram-se inativos. / The present work describes the isolation and identification or structural elucidation of the chemical constituents of the seeds of Trichilia elegans ssp. Elegans A. Juss., collected in Corumbá, MS. From the dichloromethane solubles, obtained from partition of the ethanolic extract from the seeds, eighteen substances have been isolated, after a combination of column and flash chromatography on silica gel, gel filtration and reversed phase HPLC separations. The isolated substances have been characterized as two new protolimonoids, nine new obacunol- and four new methyl ivorensate-type limonoids, in addition to two known limonoids belonging to the obacunol group (kihadanins A and B) and 3-O-&#946-D-glucopyranosyl-sitosterol. The structures of these compounds have been established on the basis of 1D (1H, 13C) and 2D (1H-1H and 1H-13C COSY, HMQC, HMBC and NOESY) NMR spectroscopic techniques, IR and mass spectral data and X-ray crystallographic analyses. Four of the isolated limonoids have been tested against DNA reparr deficient mutants of Saccharomyces cerevisiae but, nevertheless, shown to be inactive.

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