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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.
111

Clearance of amyloid-beta in Alzheimer's disease: To understand the pathogenesis and develop potential therapies in animal models

Wang, Yan-Jiang, yanjiang_wang@tmmu.edu.cn January 2010 (has links)
Alzheimer's disease (AD) is the most common cause of dementia. No strong disease-modifying treatments are currently available. Amyloid-beta peptide (Abeta) appears to play a pivotal role in the pathogenesis of AD. We focused our interest on revealing the pathogenesis of the disease and developing novel therapeutic modalities. The thesis consists of three projects: 1. Prevention of AD by intramuscular delivery of an anti-Abeta single chain antibody (scFv) gene: Immunotherapy is effective in removing brain Abetaƒzbut was associated with detrimental effects. In the present study, the gene of an anti-Abeta scFv was delivered in the hind leg muscles of APPSwe/PS1dE9 mice with adeno-associated virus at three months of age. Six months later, we found that brain Abeta accumulation, AD-type pathologies and cognitive impairment were significantly attenuated in scFv-treated mice relative to enhanced green fluorescence protein (EGFP)-treated mice. Intramuscular delivery of scFv gene was well tolerated by the animals. These findings suggest that peripheral application of scFv is effective and safe in preventing the development of AD, and would be a promising non-inflammatory immunological modality for prevention and treatment of AD. 2. Prevention of AD with grape seed derived polyphenols: Polyphenols extracted from grape seeds are able to inhibit Abetaƒnaggregation, reduce Abeta production and protect against Abeta neurotoxicity in vitro. We investigated the therapeutic effects of a polyphenol-rich grape seed extract (GSE) in vivo. APPSwe/PS1dE9 transgenic mice were fed with normal AIN-93G diet (control diet), AIN-93G diet with 0.07% curcumin, or diet with 2% GSE beginning at 3 months of age for 9 months. Total phenolic content of GSE was 592.5 mg/g dry weight, including gallic acid, catechin, epicatechin and proanthocyanidins. Long-term feeding of GSE diet was well tolerated. The Abetaƒnlevels in the brain and serum of the mice fed with GSE were reduced by 33% and 44% respectively compared with the mice fed with the control diet. Amyloid plaques and microgliosis in the brain of mice fed with GSE were also reduced by 49% and 70% respectively. In conclusion, polyphenol-rich GSE is promising to be a safe and effective drug to prevent the development of AD. 3. Roles of p75NTR in the development of AD: P75NTR has been suggested to mediate Abeta induced neurotoxicity. However, its role in the development of AD is undetermined. APPSwe/PS1dE9 transgenic mice were crossed with p75NTR knockout mice to generate APPSwe/PS1dE9 mice with p75NTR gene deleted. P75NTR mainly expressed in the basal forebrain neurons and degenerative neurites in neocortex and hippocampus. Genetic deletion of p75NTR gene in APPSwe/PS1dE9 mice reduced soluble Abeta levels, but increased the insoluble Abeta accumulation and Abeta plaque formation in the brain. P75NTR deletion decreased Abeta production of cortical neurons in vitro. Recombinant extracellular domain of p75NTR attenuated the oligomerization and fibrillation of synthetic Abeta42 peptide in vitro, and reduced local Abeta plaques after hippocampus injection in vivo. Our data suggest that p75NTR plays an important role in AD development and may be a valid therapeutic target for the treatment of AD.
112

Development of a xanthone-enriched honeybush tea extract

Bosman, Stephanie Cesa 12 1900 (has links)
Thesis (MScFoodSc)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Cyclopia genistoides (honeybush) has been identified as an excellent resource for the production of a xanthone-enriched extract due to its high mangiferin content and successful cultivation. The predominant xanthone present in C. genistoides is mangiferin, a potent antioxidant proven to exhibit a wide range of bioactivities that contribute greatly to the health-promoting abilities of honeybush extracts. Isomangiferin, the regio-isomer of mangiferin and of comparable antioxidant capacity to mangiferin, is another valuable compound present in substantial quantities in C. genistoides. A xanthone-enriched extract would find possible application in functional food/beverage products that provide health benefits beyond basic nutrition. In the current study, the effect of ethanol (EtOH) concentration (0-100%, v/v), plant material size (milled vs. teabag fraction), extraction time (0-60 min) and elevated extraction temperatures on the extraction of xanthones from unfermented C. genistoides was investigated. Single factor experiments showed the best extraction efficiency, evaluated in terms of extract yield, xanthone yield and xanthone content of the extract, was achieved by extracting milled plant material with 20-60% EtOH (v/v) for 30 min at elevated temperatures (70°C). Response surface methodology (RSM) to evaluate the individual and interaction effects of process variables, namely EtOH concentration (0-100%, v/v) and temperature (0-70°C) was used to further optimise the extraction process. EtOH concentration was found to have the largest effect on extraction efficiency (p < 0.05), whilst temperature had a negligible effect. Optimal levels of EtOH concentration (40%, v/v) and temperature (70°C) for maximum extract and mangiferin yields were successfully achieved within the experimental domain, using 10 mL/g solvent:solid ratio and 30 min extraction time. Ultrafiltration (UF) was subsequently employed to facilitate further xanthone enrichment of the unfermented C. genistoides extract (40% EtOH, v/v). A series of laboratory scale membrane devices (centrifugal membrane units, stirred cell and tangential flow ultrafiltration (TFU) system) were used in an up-scale approach to determine the effect of membrane material (regenerated cellulose (RC) vs. polyethersulphone (PES)), molecular weight cut off (MWCO; 3 kDa, 10 kDa, 30 kDa), feed concentration (1% vs. 3% soluble solids (SS)) and operating parameters (transmembrane pressure (TMP) and feed flow rate) on membrane performance and permeate quality. The best performing membrane in terms of productivity and xanthone enrichment was the 10 kDa RC membrane when using an extract concentration close to that of industrially prepared extracts (3% SS). RSM was used to further optimise UF of unfermented C. genistoides through a 10 kDa RC membrane in the TFU system. The individual and interaction effects of TMP (0.82-2.04 bar) and feed flow rate (200-444 mL/min) on permeate flux, xanthone enrichment and the fouling index were investigated. The individual effects of TMP and feed flow rate had a significant effect on all measured responses, while their interaction only affected average permeate flux and fouling index significantly. Optimal TMP and feed flow rate values of 2.04 bar and 444 mL/min, respectively, were selected within the experimental domain, restricted by equipment constraints. Validation of the combined protocol including ethanol-water extraction and UF using plant material from ten different unfermented C. genistoides batches resulted in enriched extracts containing 10.6-17.8% xanthone content. During UF, average mangiferin and isomangiferin enrichments of 20% and 22%, respectively, were obtained. Whilst no correlation was found between the feed concentration of the extracts, xanthone enrichment and fouling index, a strong linear correlation (R2 = 0.98) was found between feed concentration and permeate yield. / AFRIKAANSE OPSOMMING: Cyclopia genistoides (heuningbos) is geidentifiseer as ‘n uitstekende bron vir die produksie van ‘n xantoon-verrykte ekstrak weens sy hoë mangiferien-inhoud sowel as suksesvolle verbouing daarvan. Die oorheersende xantoon teenwoordig in C. genistoides is mangiferien, ‘n kragtige antioksidant met ‘n bewese wye reeks bioaktiwiteite wat grootliks bydra tot die gesondheidsvoordele van heuningbosekstrakte. Isomangiferien, die regio-isomeer van mangiferien met vergelykbare antioksidant-aktiwiteit as mangiferien, is nog ‘n waardevolle verbinding teenwoordig in aansienlike hoeveelhede in C. genistoides. ‘n Xantoon-verrykte ekstrak kan moontlik toegepas word in funksionele voedsel- of drankie-produkte, wat gesondheidsvoordele bo en behalwe die basiese voedsaamheid inhou. Die effek van etanol (EtOH)-konsentrasie (0-100%, v/v), plantmateriaal grootte (gemaal teenoor teesakkie-fraksie), ekstraksietyd (0-60 min) en ekstraksietemperatuur op die ekstraksie van xantone uit ongefermenteerde C. genistoides is ondersoek. Enkelfaktor eksperimente het getoon dat die beste ekstraksie-effektiwiteit, in terme van ekstrakopbrengs, xantoonopbrengs en xantooninhoud van die ekstrak, bereik is deur gemaalde plantmateriaal met 20-60% EtOH (v/v) vir 30 min by verhoogde temperature (70°C) te ekstraheer. Respons-oppervlak Metodologie (ROM) is aangewend om die individuele en interaktiewe effekte van die veranderlikes, naamlik EtOH-konsentrasie (0-100%, v/v) en temperatuur (0-70°C) te ondersoek asook om die ekstraksieproses verder te optimiseer. EtOH-konsentrasie het die grootste effek op die ekstraksie-effektiwiteit gehad (p < 0.05), terwyl die effek van temperatuur onbeduidend was. Optimale vlakke van EtOH-konsentrasie (40% v/v) en temperatuur (70°C) vir maksimum ekstrak- en mangiferienopbrengs is binne die eksperimentele domein is gevind, met die gebruik van 10 mL/g oplosmiddel:vastestof verhouding en ‘n ekstraksietyd van 30 min. Ultrafiltrasie (UF) is daarna gebruik om verdere xantoon-verryking van die ongefermenteerde C. genistoides ekstrak (40% EtOH, v/v) te fasiliteer. ‘n Reeks labratoriumskaal membraantoestelle (sentrifugale membraaneenhede, ‘n geroerde selsisteem en ‘n kruisvloei-ultrafiltrasie (KVU) sisteem) is gebruik in ‘n opskaleringsbenadering om die effek van die membraanmateriaal (geregenereerde sellulose (RS) vs. polyetersulfoon (PES)), molekulêre gewig afsnit (MWCO; 3 kDa, 10 kDa, 30 kDa), voerkonsentrasie (1% vs. 3% oplosbare vastestowwe (OV)) en operasionele parameters (transmembraandruk (TMD) en voervloeispoed) op membraanprestasie en permeaatkwaliteit te bepaal. Die membraan met die beste prestasie in terme van produktiwiteit en xantoon-verryking was die 10 kDa RS membraan wanneer gebruik met ‘n ekstrakkonsentrasie na aan dié van die industrieel vervaardigde ekstrakte (3% OV). ROM is gebruik om die KVU van ongefermenteerde C. genistoides deur ‘n 10 kDa RS membraan verder te optimiseer. Die indiwiduele en interaktiewe effekte van TMD (0.82-2.04 bar) en voervloeispoed (200-444 mL/min) op permeaatvloei, xantoon-verryking en die blokkeringindeks is ondersoek. Die individuele effekte van TMD en voervloeispoed het ‘n betekenisvolle effek op alle gemete response gehad, terwyl hul interaksie net gemiddelde permeaatvloei en besoedelingsindeks beduidend beïnvloed het. Optimale TMD en voervloeispoed waardes van 2.04 bar en 444 mL/min, onderskeidelik, is geselekteer binne die eksperimentele domein, wat bepaal is deur die beperkings van die toerusting. Die geldigheid van die gesamentlike protocol, insluitende etanol-water ekstraksie en UF, is getoets deur plantmateriaal van tien verskillende ongefermenteerde C. genistoides monsters te gebruik. Dit het gelei tot verrykte ekstrakte wat 10.6-17.8% xantone bevat het. UF het onderskeidelik gemiddelde mangiferien- en isomangiferien-verryking van 20% en 22% gelewer. Geen korrelasie is gevind tussen die voerkonsentrasie van die ekstrakte en die besoedelingsindeks nie, maar ‘n goeie liniêre korrelasie (R2 = 0.98) is tussen voerkonsentrasie en permeaatopbrengs gevind.
113

Estudo do fluido folicular, transporte, recuperaçao e maturação de oócitos em éguas superovuladas com estrato de pituitária equina /

Carmo, Márcio Teoro do. January 2007 (has links)
Resumo: A fêmea da espécie eqüina é considerada monovulatória sazonal, o que é "ator limitante a produção de embriões ao longo do ano. Esta limitação poderia inimizada se houvesse uma resposta superovulatória eficiente em melhorar a ção de embriões. Protocolos mais recentes desenvolvidos em nosso atório utilizando-se o Extrato de Pituitária Eqüina (EPE) têm permitido uma esposta superovulatória. Contudo o número de embriões recuperados ainda sido inferior ao das ovulações, em conseqüência de fatores ainda não inados. O presente estudo teve por objetivo: verificar se o tratamento com o - administrado duas vezes ao dia, altera a maturação nuclear e citoplasmática I ito, avaliar o ambiente folicular mensurando os níveis de 17(3-estradiol, E5~)tlerona, progesterona, inibina e óxido nítrico, bem como o perfil eletroforético eínas no fluido folicular entre éguas superovuladas e não superovuladas. amos também o transporte do oócito para o oviduto. Este trabalho foi o em quatro experimentos: Experimento I "Estudo do transporte dos oócitos oviduto de éguas superovuladas com extrato de pituitária eqüina"; ento II "Efeito da superovulação na recuperação de oócitos quando da ~-es foliculares guiadas por ultra-sonografia"; Experimento 111 "Avaliação do e folicular de éguas superovuladas"; Experimento IV "Avaliação da '"'ação oocitária de éguas superovuladas com extrato de pituitária equina". O ento I" foi desenvolvido na Universidade de Rio Cuarto (Argentina), foram _za.:las 22 éguas de 3 - 12 anos, (09 éguas controles; 13 éguas tratadas _ . Estes animais foram... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The equine female is considered a seasonal mono-ovulatory specie, which is a restrictive factor in respect to embryo production throughout the year. This limitation could be minimized if an efficient superovulatory response and consequent improvement of embryo production were possible. More recent protocols developed in our lab using EPE (equine pituitary extract) have allowed a good superovulatory response. However, the number of embryos recovered has been inferior to the number of ovulations detected due to unknown factors. The present study has the following objectives: Verify if the EPE treatment administered twice daily would alter the oocyte cytoplasmic and nuclear maturation; and to evaluate the follicular environment by measuring estradiol 17-, testosterone, progesterone, inhibin and nitric oxide. The electrophoresis pattern of proteins in follicular fluid from superovulated and non- superovulated mares was determined. In addition, the oocyte transport through the oviduct was investigated. The present study was divided into four experiments. Experiment I: Study of oocyte transport to the oviduct in superovulated mares using equine pituitary extract. Experiment II: Effect of superovulation on oocyte recovery using transvaginal ultrasound guided follicular aspiration. Experiment III: Evaluation of follicular environment in superovulated mares. Experiment IV: Oocyte maturation in superovulated in mares using equine pituitary extract. Experiment I was performed at Rio Cuarto University, Argentina. In the related study, 22 mares aging from 3 to 12 years were used (9 control mares, 13 EPE treated mares). These mares were monitored daily by ultrasound until the presence of a follicle ≥ 30mm in diameter, being then examined twice daily. The superovulation protocol used consisted in 25mg of EPE twice a day, intramuscularly, starting at day 7 post- ovulation... (Complete abstract click electronic access below) / Orientador: Marco Antonio Alvarenga / Coorientador: Fernanda da Cruz Landim e Alvarenga / Banca: Cezinande de Meira / Banca: Frederico Ozanam Papa / Banca: Rubens Pais de Arruda / Banca: Carlos Antonio de carvalho Fernandes / Doutor
114

Otimização da autólise de Saccharomyces cerevisiae de cervejaria e extração de RNA

Oliveira, Antonio Martins [UNESP] 16 December 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:55Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-12-16Bitstream added on 2014-06-13T20:24:24Z : No. of bitstreams: 1 oliveira_am_dr_rcla.pdf: 1319026 bytes, checksum: b6ad03694a53b696678fbabde842876e (MD5) / O presente trabalho teve por objetivo otimizar a autólise de levedura fresca de cervejaria (Saccharomyces cerevisiae), visando a extração máxima de ácido ribonucléico da biomassa na produção do extrato de levedura. As variáveis estudadas foram pH, temperatura, % de NaCl, % de NH3, tempo de processo e, métodos de recuperação de RNA do autolisado. Os experimentos foram realizados por meio de quatro ensaios delineados segundo Box & Benken (1989) e avaliado pela Metodologia da Superfície de Resposta, utilizando-se o Software Statística 5.1 e a análise estatística ANOVA. A otimização foi concluída por meio do quinto ensaio com a produção do extrato nas condições otimizadas (55,2ºC, 9,8% de NaCl em pH=5,1 por 24 horas e, 12,2% de NH3 a 60ºC sob agitação a 200 rpm/15minutos. Três métodos foram avaliados para recuperação do RNA e das frações de extrato e parede celular: 1) autólise/plasmólise; 2) choque térmico por 1 minuto a 68ºC seguido da autólise/plasmólise 3) hidrólise química alcalina. Pelo processo de autólise em combinação com 9,8% de NaCl, a taxa de extração de RNA em 24 horas foi de 89,7%, com um rendimento de 51,3% em massa de extrato com 57,9% de proteína e, 48,7% de parede celular desidratada com 21,7 % de proteína. A utilização de 12,2% de NH3 em base seca de levedura permitiu o aumento na taxa de extração de RNA de 89,7 para 93,6%, mas um forte escurecimento foi verificado no extrato obtido. Na recuperação do RNA após precipitação protéica em pH 4,3 com posterior uso de 2 volumes de etanol em pH=2, recuperou-se 15,47%, 13,80% e 7,42% de RNA respectivamente com purezas de 49,85%, 51,70% e 38,70%. As taxas de extração de RNA da biomassa foram de 87,45% para o método 1; 91,40% para o método 2 e 78,80% para o terceiro método, indicando uma boa alternativa para redução do teor de RNA da biomassa e produção do extrato rico... / The present work had for objective to optimize the autolysis of fresh brewery’s yeast (Saccharomyces cerevisiae), aiming the maximum extraction of ribonucleic acid of biomass in the yeast extract production. The studied variables were pH, temperature, % of NaCl, % NH3, processing time and RNA recovering methods from autolysed. The experiments were accomplished by mean of four delineated assays according to Box & Benken (1989) and evaluated by Surface Methodology of Answer, utilizing the software Statistica 5.1. and the analysis statistics “ANOVA”. The optimization was concluded by mean of the fifth assay with an extract production in the optimized conditions (55.2ºC, 9.8% of NaCl in pH 5.1 for 24 hours and, 12.2% of NH3 at 60ºC under agitation at 200 rpm/15 minutes. Tree methods were evaluated for RNA recovering and of the extract fractions and cell wall: 1) autolysis/plasmolysis; 2) thermic shock during 1 minute at 68ºC followed of autolysis/plasmolysis; 3) alkaline chemical hydrolysis. The process of autolysis in combination with 9.8% of NaCl, the RNA extraction yield in 24 hours was of 89.7%, with a yield of 51.3% in extract mass with 57.9% of protein and, 48.7% of dehydrated cell wall with 21.7% of protein. The utilization of 12.2% of NH3 in dried base of yeast allowed the increase in the RNA yield extraction from 89.7 to 93.6%, but a strong darkness was observed in the obtained extract. The RNA recovering after 4.3 pH proteic precipitation with posterior use of 2 ethanol volumes in pH 2.0, it was recovered 15.47%, 13.8% and 7.42% of RNA respectively with purities of 49.85%, 51.70% and 38.70%. The RNA extraction yields of biomass were of 87.45% for the method 1; 91.40% for the method 2 and 78.80% for the third method, indicating a good alternative for RNA content reduction of biomass and rich extract production in nucleotides. The extract fractions were evaluated... (Complete abstract click electronic access below)
115

Biocidas naturais e seus reflexos sobre contaminantes na produção de etanol /

Badin, Flavio. January 2010 (has links)
Orientador: Márcia Justino Rossini Mutton / Banca: Flávia Cecílio Ribeiro Bregagnoli / Banca: Francisco Vicente Gaiotto Cleto / Resumo: As indústrias sucroenergéticas têm como preocupação o controle de contaminantes da fermentação, responsáveis por afetar a viabilidade da levedura, provocando diversos transtornos no processo, comprometendo a eficiência fermentativa e o rendimento industrial. Dentre as alternativas para o controle das contaminações, destacam-se o uso de antimicrobianos sintéticos. Sua utilização continua pode favorecer o desenvolvimento de cepas resistentes, contribuindo para o incremento do custo de produção, além da possibilidade de incorporação de resíduos no produto final. Objetivou-se avaliar o efeito do biocida convencional (monensina sódica) e biocidas naturais preparados à base de própolis (Extrato Hidroalcoólico de Própolis - EHP e Extrato Oleoso de Própolis- EOP) sobre a fisiologia das leveduras, o controle dos contaminantes do processo fermentativo e composição do destilado. O delineamento experimental utilizado foi o Inteiramente Casualizado com parcelas subdivididas, com 4 repetições. Os Tratamentos Principais foram: Testemunha, EOP, EHP e monensina sódica (Kamoran WP). Os Tratamentos Secundários constituíram-se nos 10 ciclos fermentativos. Avaliaram-se as características químico-tecnológicas do caldo, mosto e vinho, parâmetros microbiológicos das leveduras e composição do destilado obtido. Os resultados obtidos demonstraram que os biocidas avaliados apresentaram efeito similar, sendo efetivos no controle dos contaminantes da fermentação, não afetando negativamente suas características fisiológicas. Não afetaram a composição a composição do destilado final obtido / Abstract: The control of fermentation contaminants is one of the sugar mills concerns. The fermentation contaminants are responsible to affect the yeast viability, generating several overturns to the process, compromising the fermentative efficiency as well the industrial yield. Among the alternatives to control contamination, the use of synthetic antimicrobials can be highlighted. Its progressed use may favor the development of resistant strains, contributing in production cost improving, besides the possibility of residues incorporation into the final product. This work aimed evaluate the effect of conventional biocides (sodic monensin) and natural ones based on propolis (Propolis Hydroalcoholic Extract - EHP and Propolis Oily Extract - EOP) under the yeasts physiology, the fermentative process contaminants control, and the distilled composition. The experimental design used was the split-plot with four replications. The main treatments were: Control, EOH, EHP, and sodic monensin (Kamoran WP). The secondary treatments were the 10 fermentative cycles. The evaluated characteristics were: juice, must, and wine chemical-technical characteristics, yeasts microbiologic parameters, and the distillated obtained composition. The results obtained showed that the evaluated biocides presented similar effect, being effectives to control the fermentation contaminants, not affecting negatively its physiologic characteristics. They did not affect the composition of the distilled obtained / Mestre
116

Aditivos naturais encapsulados em sílicas híbridas : aplicação em conservação de alimentos

Steiner, Alexandra Duprates January 2015 (has links)
Visando atender às necessidades de consumidores mais exigentes e preocupados com a saúde, este trabalho propôs um estudo de propriedade antimicrobiana de extratos naturais como antocianinas, tanino, urucum, curcumina e extrato de folha de oliveira e antioxidante para antocianinas, todos em sua forma livre e encapsulados numa rede de sílica. Diante das características de mudança de coloração do extrato de antocianinas frente à alteração de pH do meio o uso desse composto no desenvolvimento de filme em matriz polimérica de quitosana/PVA como embalagem ou etiqueta ativa e inteligente. Os extratos foram encapsulados em sílica em diferentes concentrações variando de 2,5% a 50% utilizando rota ácida e rota básica com precursor tetraetoxisilano e caracterizados quanto à preservação da funcionalidade e estrutura molecular, textura e morfologia e estabilidade térmica. Os filmes foram avaliados quanto às propriedades mecânicas, espessura, análises térmicas, caracterização química e análise de mudança de cor com filé de peixe tilápia (Tilápia rendali) cru com aplicação direta sobre a carne, sob refrigeração, correlacionada com mudança de pH do peixe e Contagem Bacteriana Total (CBT). Os resultados obtidos foram promissores, uma vez que dentre os bioativos livres o urucum, tanino e antocianina apresentaram resultados bastante satisfatórios quanto à ação antimicrobiana com zona de inibição no método de difusão entre 10 a 22 mm. Quando encapsulados, os extratos destaque foram a antocianina e o tanino com zona de inibição entre 9 a 21mm. Quanto ao filme indicador avaliado demonstrou ser um bom indicador de pH ao mudar de cor via colorímetro mas a olho nu a mudança não foi percebida nitidamente. A sua resistência à ruptura aumentou em aproximadamente 20 vezes em relação ao filme controle. Entretanto a deformação na ruptura diminuiu em torno de 30% tornando-o mais rígido. / The present work investigated needs of demanding and concerned consumers with their health, this work proposes a study of antimicrobial and/or antioxidant properties of natural extracts as anthocyanins, tannin, anatto, curcumin and olive leaf extracts and antioxidant for anthocyanins, in free state and encapsulated within silica network. Due to of color change features of anthocyanins extract under pH variation, this compound was used in the preparations of quitosan/PVA film as intelligent and active packaging. The extracts were encapsulated in silica in different concentrations from 2,5% to 50% using acid and basic sol-gel catalyzed route route with tetraetoxisilane as precursor and characterized as the funcionality preservation and molecular structure, texture and morfology and thermal estability. The films were evaluated in terms of mechanical properties, thickness, thermal analysis, chemical characterization and fish fillet tilápia (Tilápia rendali) crude color change analysis with direct application on meat, under refrigeration, correlated with fish pH changing and Total Bacterial Counting (CBT). The results were promising since among the free bioactive the anatto, tannin and anthocyanin showed very satisfactory results in terms of antimicrobial action with inhibition zone in the diffusion method between 10 to 22 mm. When encapsulated, the featured extracts were anthocyanin and tannin with inhibition between 9 to 21mm. The measured indicator film demonstrated to be a good pH indicator because color changing through colorimeter but to the naked eye the color changing was not clearly observed. The rupture strength increased about 20 times comparing to the control film. However the elongation at break decreases around 30% turning it hard.
117

Avaliação de bactérias psicrotróficas presentes em presunto cozido fatiado e a influência de fatores ambientais na manutenção da qualidade microbiológica e inocuidade do alimento / Evaluation of the psychotrophic bacteria present in sliced baked ham and the influence of environmental factors in maintenance of microbiological quality and food safety

Tallamini, Stéfano Caon January 2016 (has links)
Este estudo objetivou analisar o potencial de deterioração da microbiota psicrotrófica presente em presunto cozido fatiado comercializado entre Maio e Junho de 2015 e Fevereiro e Março de 2016 no mercado público da cidade de Porto Alegre/RS e avaliar a influência de fatores ambientais na qualidade microbiológica do mesmo. Os presuntos foram coletados em 4 bancas desse local e foram realizadas contagens de bactérias psicrotróficas de 8 amostras e pesquisa de Listeria monocytogenes. Selecionaram-se 134 colônias de psicrotróficos isolados de presunto fatiado, 71 deles apresentaram atividade proteolítica, 58 atividade lipolítica e 12 apresentaram produção de exopolissacarídeo. Selecionaram-se 2 bactérias com a presença dessas atividades para identificação molecular, as quais foram identificadas como Kluyvera sp. e Carnobacterium sp. Além delas, mais 2 Listeria monocytogenes isoladas nesse trabalho foram submetidas ao teste de produção de biofilme, resultando como fracas formadoras e também ao teste de aderência em aço inoxidável, todas apresentando capacidade de adesão. A pesquisa de Listeria monocytogenes nos presuntos fatiados mostrou 100% de presença, sendo que 50% foram identificadas como L. monocytogenes, as quais pertenceram aos sorotipos 1/2a (1), 1/2b (2), 1/2c (2). Realizou-se análise de presunto cozido inteiro, em sua embalagem original, sendo que não foram encontrados micro-organismos Tratou-se o presunto fatiado com extrato de hibisco a 40% e pediocina a 0,5% e 1,0% e realizou-se contagem de mesófilos, psicrotróficos, Listeria spp., S. aureus e E.coli. O extrato de hibisco reduziu a carga desses micro-organismos. Pediocina 0,5% e 1% apresentaram pouca ação frente ao controle de mesófilos, psicrotróficos e E. coli, mas mantiveram a carga de S. aureus controlada e foram eficazes contra Listeria spp. Foram realizadas também contagens para Listeria monocytogenes, E. coli, S. aureus, mesófilos e psicrotróficos em suabes oriundos de fatiador de alimentos, superfície de contato e utensílio utilizados nas bancas do mercado público. Em conclusão grande parte dos psicrotróficos apresentou atividade proteolítica e lipolítica, as quais alteram organolepticamente o alimento. Alguns apresentaram produção de biofilme e capacidade de aderência, fato indesejado, pois sua remoção é mais difícil no ambiente industrial, com isso nota-se que a legislação brasileira apresenta carência na contagem de psicrotróficos em produtos cárneos. / This study aimed to evaluate the microbiota present in sliced cooked ham sold in the public market in Porto Alegre/RS and evaluate the ability of compounds with antimicrobial activity of hibiscus extract and pediocin to control the microbiota found. Ham collected was stored refrigerated until to arrive the laboratory for analysis. Psychrotrophic bacteria counts were performed. Were selected 134 colonies of psychrotrophic microorganisms isolated for sliced ham and 71 of them showed proteolytic activity, 58 lipase activity, 12 showed production of exopolysaccharide. Two of these bacteria were selected for molecular identification which were identified as Kluyvera sp. and Carnobacterium sp. These two bacteria plus two Listeria monocytogenes isolated for sliced ham were subjected to testing of biofilm production (resulting as weak forming of biofilm) and were tested for adhesion in stainless steel and all showed this property. The research of Listeria spp. in sliced cooked ham showed 100% of presence, which 50% were identified as L. monocytogenes to serotypes 1/2a (1) 1/2b (2), 1/2c (2). Analysis was carried out of a whole piece of cooked ham in its original packaging and none microorganisms were found. The sliced ham was treated with hibiscus extract of 40% and pediocin of 0.5% and 1.0% and has been mesophilic, psychrotrophic, Listeria spp., S. aureus and E. coli counts The hibiscus extract reduced the quantity of these microorganisms. Pediocin 0.5% and 1,0% had little action against the control of mesophilic, psychrotrophic and E. coli, but in S. aureus counts were controlled bacteria charge and were effective against Listeria spp.. Also counts of Listeria monocytogenes, E. coli, S. aureus, mesophilic and psychrotrophic bacteria were performed from swabs of slicer food, contact surface and food tool (knife or spatula) used in public market stalls. In conclusion, most of the psychrotrophs presented proteolytic and lipolytic activity, which alter organoleptically the food. Some of them have presented biofilm production and adhesion capacity, undesirable fact because when the biofilm is formed is more difficult to remove it in the industrial environment. With this it is showed that the brazilian legislation presents a lack in the research of psychrotrophs in meat products kept refrigerated.
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Bioatividade de derivados de Annonaceae sobre Helicoverpa armigera (Hübner, 1808) (Lepidoptera: Noctuidae) / Bioactivity of annonaceae derivatives on Helicoverpa armigera (Hübner, 1808) (Lepidoptera: Noctuidae)

Moreira de Souza, Camila [UNESP] 24 February 2016 (has links)
Submitted by CAMILA MOREIRA DE SOUZA null (souza_767@hotmail.com) on 2016-04-18T19:46:00Z No. of bitstreams: 1 Dissertação Camila VERSÃO FINAL!!.pdf: 1089941 bytes, checksum: 0056d988ce48567a07396904b6b56cf3 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-04-25T17:26:34Z (GMT) No. of bitstreams: 1 moreiradesouza_c_me_bot.pdf: 1089941 bytes, checksum: 0056d988ce48567a07396904b6b56cf3 (MD5) / Made available in DSpace on 2016-04-25T17:26:34Z (GMT). No. of bitstreams: 1 moreiradesouza_c_me_bot.pdf: 1089941 bytes, checksum: 0056d988ce48567a07396904b6b56cf3 (MD5) Previous issue date: 2016-02-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Helicoverpa armigera (Hübner, 1808) (Lepidoptera: Noctuidae) destaca-se pela grande capacidade de dispersão, hábito polífago e por ocasionar expressivos danos em culturas de interesse econômico em todo o mundo. Dentre os métodos de manejo de insetos-praga, o uso de derivados vegetais é considerado uma promissora alternativa ao controle químico, uma vez que estes produtos apresentam mais de um ingrediente ativo em sua composição, dificultando a seleção de insetos resistentes, além de serem provenientes de recursos renováveis. Dentre as famílias botânicas de ocorrência em regiões neotropicais, Annonaceae constitui uma das principais fontes de compostos naturais bioativos. Assim, visando disponibilizar alternativas mais sustentáveis e ao mesmo tempo eficientes para o manejo de Helicoverpa armigera (Hübner, 1808) (Lepidoptera: Noctuidae), avaliou-se a bioatividade de cinco derivados de anonáceas (Annona montana Macfad., A. mucosa Jacq., A. muricata L., A. reticulata L. e A. sylvatica A. St.-Hil.) e do produto comercial à base de acetogeninas de anonáceas (Anosom® 1 EC) sobre lagartas do inseto. Adicionalmente, o composto majoritário do extrato mais ativo foi identificado e também avaliado quanto à sua bioatividade sobre formas neonatas de H. armigera. Constatou-se que o extrato de A. mucosa (CL50: 411,55 mg kg-1 e CL90: 1.479 mg kg-1 ) assim como o Anosom® 1 EC (CL50: 312,08 mg kg-1 e CL90: 1.151 mg kg-1 ) apresentaram significativa atividade inseticida sobre H. armigera, com toxicidade aguda após sete dias de exposição a dieta artificial tratada. A partir do extrato etanólico de A. mucosa realizou-se fracionamento biomonitorado através de diferentes técnicas cromatográficas, permitindo o isolamento da acetogenina bisterahidrofurano roliniastatina-1. Este composto foi testado a uma concentração de 41,55 mg kg-1 , ocasionando mortalidade total das larvas de H. armigera após o quarto dia de incorporação à dieta. Na sequência, em casa de vegetação, avaliou-se a toxicidade comparada do extrato etanólico de A. mucosa, do Anosom® 1 EC (ambos na CL90 estimada) e do inseticida de origem sintética (Belt® 48 SC) sobre larvas neonatas do inseto em plantas de tomateiro. Neste ensaio, todos os tratamentos causaram significativa mortalidade larval (> 90%) do inseto. Por fim, avaliou-se o efeito do extrato etanólico de sementes de Annona mucosa L. e do inseticida comercial botânico Anosom® 1 EC na CL50 (411,55 e 312,08 mg kg-1 , respectivamente) sobre o comportamento alimentar e alguns parâmetros biológicos de H. armigera em dieta artificial. Constatou-se alteração no comportamento alimentar de lagartas de quarto ínstar de H. armigera expostas a dieta artificial contendo Anosom® 1 EC e extrato etanólico de A. mucosa, com significativa redução no consumo após 48 horas de exposição. Ambos os tratamentos prolongaram a fase larval (acréscimo de seis dias em dieta tratada com Anosom® 1 EC e sete dias em dieta tratada com extrato etanólico de A. mucosa). Também foi vericado reduções na viabilidade larval (25,00 % para o Anosom® 1 EC e 23,00 % para A. mucosa) e pupal (34,44 % para Anosom® 1 EC e 24,99 % para A. mucosa) assim como no peso médio de pupas (redução de aproximadamente 69,31 % para o Anosom® 1 EC e 70,80 % para A. mucosa). Os resultados obtidos neste estudo são inéditos e indicam que o extrato etanólico de A. mucosa apresenta bom potencial no controle alternativo de H. armigera, podendo ser inserido como estratégia eficiente em programas de manejo integrado do inseto, principalmente em cultivos orgânicos ou protegidos. / Helicoverpa armigera (Hübner, 1808) (Lepidoptera: Noctuidae) is a highly polyphagous species with high dispersion ability and adaptability to different crops of economic interest worldwide. Botanical insecticides emerge as a viable alternative to the use of synthetic insecticides for pest management because they have more of a potentially active ingredient in their composition, delaying the selection of resistant insect, moreover come from renewable resources. Among tropical plant families, the Annonaceae has shown great potential as a source of biopesticides. To determine an alternative tool for H. armigera control, this study evaluated the insecticidal activity of ethanolic seed extracts from five species of Annonaceae (Annona montana Macfad., A. mucosa Jacq., A. muricata L., A. reticulata L. e A. sylvatica A. St.-Hil.) and the acetogenin-based commercial bioinsecticide Anosom® 1 EC on larvae of H. armigera larvae. In addition, the major active compound of the ethanolic extract was isolated using various chromatographic techniques and assessed for its bioactivity on H. armigera neonates. In the initial screening assay we verified that the ethanolic seed extract from A. mucosa (LC50 = 411.55 mg kg-1 and LC90 = 1,479 mg kg-1 ) was the most promising one, showing similar effectiveness to Anosom® 1 EC (LC50 = 312.08 mg kg-1 and LC90 = 1,151 mg kg-1 ) against H. armigera at seven days after exposition to treated diet. The acetogenin bis-tetrahydrofuran rolliniastatin-1 was identified as the major compound in ethanolic extract from A. mucosa. This compound was assessed at 41.55 mg kg- 1 , causing 100 % of larval mortality on H. armigera neonates for days after exposition to treated diet. After, in a greenhouse trial using tomato plants, the bioactivity of ethanolic extract of A. mucosa was compared to botanical insecticide Anosom® 1 EC (both at LC90) and a synthetic insecticide (Belt® 48 SC) on neonate larvae of H. armigera. In this test, all treatments led to significant larval mortality (> 90 %). In the last step, the bioactivity of the extract from A. mucosa and Anosom® 1 EC at LC50 (411.55 and 312.08 mg kg-1 , respectively) were evaluated against H. armigera for feeding behavior and growth inhibitory effects, using dietary exposure bioassays. The feeding behavior effect was evaluated for 4- ínstar H. armigera larvae after exposure to Anosom® 1 EC and A. mucosa-treated diets, with significate consume reduction after a 48-hour exposition. Both treatments prolonged the larval phase duration (six days for Anosom® 1 EC -treated diet and seven days for A. mucosatreated diet). The larval (25.00% for Anosom® 1 EC and 23.00% for A. mucosa) and pupal (34.44% for Anosom® 1 EC and 24.99% for A. mucosa) viabilities decreased significantly, as well as the pupal weight (69.31% for Anosom® 1 EC and 70.80% for A. mucosa). The results obtained in this study are novel and demonstrate that the ethanolic extract from A. mucosa has great potential as alternative control method against H. armigera. This tool can be added as an effective strategy in integrated management programs of this pest, especially in organic or protected crops.
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Uso de Ascophyllum nodosum para o enraizamento de microestacas de eucalipto

Losi, Livia Creste [UNESP] 02 September 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:47Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-09-02Bitstream added on 2014-06-13T20:55:20Z : No. of bitstreams: 1 losi_lc_me_botfca.pdf: 446005 bytes, checksum: 7d7c4bb09f14e32d875db21ebf299ae5 (MD5) / Universidade Estadual Paulista (UNESP) / O presente trabalho teve por objetivo avaliar os efeitos de diferentes doses de extrato de Ascophyllum nodosum na produção de mudas de Eucalytus urograndis e Eucalyptus urophilla durante a fase de enraizamento. Os experimentos foram conduzidos em casa de vegetação, pertencentes às empresas VEC Florestal e Monte Flora, produtoras de microestacas de eucalipto e localizadas na cidade de Bofete, estado de São Paulo. O experimento foi conduzido em quatro fases no período de abril de 2009 a março de 2010, utilizando-se dois clones de E. urograndis (Euca 103 e Euca 105) e um clone de E. urophilla (I144), dois substratos (Brasil Minérios e Carolina Soil) e aplicação de diferentes doses de extrato de A. nodosum (EAN) 0, 0,5, 1, 1,5, 2, 3, 4, 8 e 16 mL L-1. O delineamento experimental adotado foi em blocos ao acaso com 4 repetições e 86 plantas por parcela. As aplicações do extrato de A. nodosum ocorreram aos 0, 7, 14, 21 e 28 dias após o estaqueamento variando conforme a fase. Foram avaliados a massa fresca de raiz (MFR), massa seca de raiz (MSR), comprimento de raiz (CR), massa fresca de parte aérea (MFA), massa seca de parte aérea (MAS), diâmetro do caule (D) e quantidade de raiz (Q) aos 30 e 45 2 dias após dias após o estaqueamento e análise química da planta. As avaliações permitiram observar que houve resposta diferenciada do EAN em relação aos substratos e ao material genético. O tratamento na dose de 3 mL de EAN para o clone I144 proporcionou melhor enraizamento das microestacas. Observou-se também que a forma de aplicação do produto interfere nos resultados / The objective of this work was to evaluate the effects of different rates of extract of Ascophyllum nodosum in the production of microshoots Eucalyptus urograndis and Eucalyptus urophilla during the rooting. The experiments were conducted in a greenhouse belonging to companies VEC Florestal and Monte Flora, two producers of microcuttings eucalyptus and located in the city of Bofete, State of São Paulo. The experiment was conducted in four phases between April 2009 and March 2010, using two clones of E. urograndis (Euca 103 e Euca 105) and one clone of E. urophilla (I144), two substrates (Brasil Minérios and Carolina Soil) and application of different rates of extract A. nodosum (EAN) 0, 0,5, 1, 1,5, 2, 3, 4, 8, 16 mL L-1. The experimental design used was randomized blocks with four replications and 86 plants per plot. The applications of the extract A. nodosum occur at 0, 7, 14, 21 and 28 days after the cutting. It were evaluated root fresh weight (MFR), root dry mass (MSR), root length (CR), fresh weight of shoot (MFA), shoot dry mass (MAS), stem diameter (D) and quality of root (Q) at 30 and 45 days after the cutting. The evaluations allowed to note that there was differential response of EAN in relation to substrates and genetic material, The dose of 3 mL of ean for clone I144 provided better microcuttings rooting. It was also observed that the way of the product application affect the results
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Estudo do fluido folicular, transporte, recuperaçao e maturação de oócitos em éguas superovuladas com estrato de pituitária equina

Carmo, Márcio Teoro do [UNESP] January 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2007Bitstream added on 2014-06-13T20:06:45Z : No. of bitstreams: 1 carmo_mt_dr_botfmvz.pdf: 1969502 bytes, checksum: 198972891441c6a64f8bf48146e2e8b1 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A fêmea da espécie eqüina é considerada monovulatória sazonal, o que é ator limitante a produção de embriões ao longo do ano. Esta limitação poderia inimizada se houvesse uma resposta superovulatória eficiente em melhorar a ção de embriões. Protocolos mais recentes desenvolvidos em nosso atório utilizando-se o Extrato de Pituitária Eqüina (EPE) têm permitido uma esposta superovulatória. Contudo o número de embriões recuperados ainda sido inferior ao das ovulações, em conseqüência de fatores ainda não inados. O presente estudo teve por objetivo: verificar se o tratamento com o - administrado duas vezes ao dia, altera a maturação nuclear e citoplasmática I ito, avaliar o ambiente folicular mensurando os níveis de 17(3-estradiol, E5~)tlerona, progesterona, inibina e óxido nítrico, bem como o perfil eletroforético eínas no fluido folicular entre éguas superovuladas e não superovuladas. amos também o transporte do oócito para o oviduto. Este trabalho foi o em quatro experimentos: Experimento I Estudo do transporte dos oócitos oviduto de éguas superovuladas com extrato de pituitária eqüina; ento II Efeito da superovulação na recuperação de oócitos quando da ~-es foliculares guiadas por ultra-sonografia; Experimento 111 Avaliação do e folicular de éguas superovuladas; Experimento IV Avaliação da ''ação oocitária de éguas superovuladas com extrato de pituitária equina. O ento I foi desenvolvido na Universidade de Rio Cuarto (Argentina), foram _za.:las 22 éguas de 3 - 12 anos, (09 éguas controles; 13 éguas tratadas _ . Estes animais foram... / The equine female is considered a seasonal mono-ovulatory specie, which is a restrictive factor in respect to embryo production throughout the year. This limitation could be minimized if an efficient superovulatory response and consequent improvement of embryo production were possible. More recent protocols developed in our lab using EPE (equine pituitary extract) have allowed a good superovulatory response. However, the number of embryos recovered has been inferior to the number of ovulations detected due to unknown factors. The present study has the following objectives: Verify if the EPE treatment administered twice daily would alter the oocyte cytoplasmic and nuclear maturation; and to evaluate the follicular environment by measuring estradiol 17-, testosterone, progesterone, inhibin and nitric oxide. The electrophoresis pattern of proteins in follicular fluid from superovulated and non- superovulated mares was determined. In addition, the oocyte transport through the oviduct was investigated. The present study was divided into four experiments. Experiment I: Study of oocyte transport to the oviduct in superovulated mares using equine pituitary extract. Experiment II: Effect of superovulation on oocyte recovery using transvaginal ultrasound guided follicular aspiration. Experiment III: Evaluation of follicular environment in superovulated mares. Experiment IV: Oocyte maturation in superovulated in mares using equine pituitary extract. Experiment I was performed at Rio Cuarto University, Argentina. In the related study, 22 mares aging from 3 to 12 years were used (9 control mares, 13 EPE treated mares). These mares were monitored daily by ultrasound until the presence of a follicle ≥ 30mm in diameter, being then examined twice daily. The superovulation protocol used consisted in 25mg of EPE twice a day, intramuscularly, starting at day 7 post- ovulation... (Complete abstract click electronic access below)

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