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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.
491

Healing of cranial critical sized defects with grafts, stem cells, growth factors and bio-materials

Lappalainen, O.-P. (Olli-Pekka) 01 November 2016 (has links)
Abstract Bone is a highly vascularized tissue which enables a close interaction between blood vessels and osteoid complexes, including osteoblasts and osteoclasts. Iatrogenic bone loss, caused by a surgical intervention or trauma, disrupts circulation in the bone and leads to hypoxia and even necrosis of the adjacent bone. The mechanisms of the bone tissue healing process by regeneration are highly specific. The most common and predictable way to manage a large-sized skull bone defect has traditionally been using the patient’s own bone tissue graft. The problem with the method is damage and pain of the donor site caused by the operation and healing problems. In paediatric patients, there is a limited availability of adequate autologous bone grafts. For this reason, efforts have been made to develop substitute materials in order to avoid the need for large bone grafts. Autologous stem cells have proven to be promising targets for the development of bone substitutes for cranio-maxillofacial bone defects. The main objective of this study was to examine, by using an experimental animal model, differences in the healing of critical-sized calvarial bone defects, similar to cranioplasty, induced with different types of autogenous bone grafts and with adipose tissue- or bone marrow-derived stem cells grown in two commonly used biomaterials, tricalcium phosphate and bioglass. We also investigated the effect of tissue adhesive, fibrin glue, on the healing process of bone defects. The effect of the stimulating growth factor proteins BMP-2, BMP-7 and VEGF on tissue transplants and ossification was also studied. The results of this study support the previously reported findings of accelerated bone graft resorption associated with autologous bone graft use. In particular, the use of fibrin tissue glue in combination with autologous particulated bone grafts reduced the formation of new bone in calvarial lesions. During the initial healing of calvarial bone defects, tricalcium phosphate granules proved to be more effective than solid bioactive glass scaffolds. Furthermore, in combination with adipose-derived stem cells, tricalcium phosphate showed better bone regeneration than the same cells in combination with a bioactive glass scaffold. Combining bone marrow-derived stem cells with biomaterial did not increase bone formation in calvarial critical-sized defects. In this study, there was no evidence of the positive effect of growth factors on cranial bone healing. / Tiivistelmä Luu on runsaasti verisuonitettua kudosta, ja se mahdollistaa tiiviin vuorovaikutuksen verisuonten ja luun rakenteen perusyksikön, osteonin, sekä toiminnallisten solujen osteoblastien ja osteoklastien välillä. Kirurgisen toimenpiteen tai trauman aiheuttama luun vaurio häiritsee luun verenkiertoa ja johtaa hapenpuutteeseen ja jopa nekroosiin vaurioituneessa luun osassa. Luukudoksen paranemisen ja uudistumisen mekanismit ovat pitkälle erilaistuneita ja ne tunnetaan erittäin hyvin. Yleisin ja ennusteeltaan luotettavin tapa korjata laajoja kallon luukudoksen puutoksia on perinteisesti ollut potilaan oman luukudossiirteen käyttö. Menetelmän ongelmana on siirteen luovutuskohdan vaurio ja kipu sekä paranemiseen liittyvät ongelmat. Erityisesti lapsipotilailla on haasteena riittävän siirreluumäärän rajoitettu saatavuus. Tästä syystä on pyritty kehittämään korvaavia materiaaleja, jotta vältettäisiin suuriin luusiirteisiin liittyviä ongelmia. Autologiset kantasolut ovat osoittautuneet lupaaviksi kehitettäessä luuta korvaavia hoitomuotoja kallon luupuutosten hoitoon. Tämän tutkimuksen päätavoitteena oli tutkia kokeellisen eläinmallin avulla laajojen, kallokirurgiassa aiheutuvia luupuutoksia vastaavien vaurioalueiden paranemista. Tutkimuksessa testattiin erityyppisiä autogeenisiä luusiirteitä ja rasvakudos- tai luuydinperäisiä kantasoluja, joita kasvatettiin kahden biomateriaalin, trikalsiumfosfaatin ja bioaktiivisen lasin pinnoilla. Tutkimuksessa selvitettiin myös fibriinikudosliiman vaikutusta omakudosluusiirteen paranemiseen. Kudoskasvutekijäproteiinien BMP-2, BMP-7 ja VEGF stimuloivaa vaikutusta kudossiirteiden toimintaan ja luutumiseen selvitettiin myös. Tämän tutkimuksen tulokset tukevat aiemmin raportoituja havaintoja autologisen luusiirrännäisen käyttöön liittyvästä nopeasta resorptiosta. Erityisesti fibriinikudosliiman käytön yhdessä autologisten pienipartikkelisten luusiirteiden kanssa havaittiin heikentävän uuden luun muodostumista kallon luupuutoksissa. Kallon luupuutosten alkuvaiheen paranemisessa rakeinen trikalsiumfosfaatti osoittautui tehokkaammaksi kuin kiinteä säikeinen bioaktiivinen lasi. Samoin rasvakudosperäisten kantasolujen yhdistäminen trikalsiumfosfaattiin lisäsi merkittävästi luun muodostumista verrattuna samaan yhdistelmään bioaktiivisen lasin kanssa. Luuydinperäisiä kantasoluja yhdistettäessä vastaavaa ei voitu tässä tutkimuksessa todeta. Tutkimuksessa kasvutekijöiden käytöllä ei havaittu olevan positiivista vaikutusta kallonluiden paranemiseen.
492

Eco-designed functionalization of polyester fabric

Agnhage, Tove January 2017 (has links)
There is an increased awareness of the textile dyeing and finishing sector’s high impact on the environment due to high water consumption, polluted wastewater, and inefficient use of energy. To reduce environmental impacts, researchers propose the use of dyes from natural sources. The purpose of using these is to impart new attributes to textiles without compromising on environmental sustainability. The attributes given to the textile can be color and/or other characteristics. A drawback however, is that the use of bio-sourced dyes is not free from environmental concerns. Thus, it becomes paramount to assess the environmental impacts from using them and improve the environmental profile, but studies on this topic are generally absent. The research presented in this thesis has included environmental impact assessment, using the life cycle assessment (LCA) tool, in the design process of a multifunctional polyester (PET) fabric using natural anthraquinones. By doing so an eco-design approach has been applied, with the intention to pave the way towards eco-sustainable bio-functionalization of textiles. The anthraquinones were obtained from the root extracts of the madder plant (Rubia tinctorum L.), referred to as madder dye. The research questions were therefore formulated related to the use of madder dye. Three research questions have been answered: (I) Can madder dye serve as a multifunctional species onto a PET woven fabric? (II) How does the environmental profile of the dyeing process of PET with madder dye look like, and how can it be improved? (III) What are the main challenges in using LCA to assess the environmental impacts of textile dyeing with plant-based dyes? It is concluded that there is a potential for the madder dye to serve as a multifunctional species onto PET. Based on the encouraging result, a recommendation for future work would be to focus on the durability of the functionalities presented and their improvement potential, both in exhaustion dyeing and pad-dyeing. LCA driven process optimization of the exhaustion dyeing enabled improvement in every impact category studied. However, several challenges have been identified which need to be overcome for the LCA to contribute to the sustainable use of multifunctional plant-based species in textile dyeing. The main challenges are the lack of available data at the research stage and the interdisciplinary nature of the research arena. It is envisaged that if these challenges are addressed, LCA can contribute towards sustainable bio-functionalization of textiles. / Le secteur de la teinture et de l’ennoblissement textile est de plus en plus conscient de son impact sur l’environnement dû principalement à la consommation élevée de l’eau et à sa pollution, et aux pertes d’énergie. Pour réduire ces impacts, les chercheurs proposent l’utilisation de molécules issues de ressources naturelles, pour traiter les textiles en limitant les impacts sur l’environnement. C’est le cas pour l’obtention de textiles colorés ou pour l’attribution de toute autre fonctionnalité. Cependant, il n’est pas évident que ces molécules bio-sourcées n’aient aucun impact sur l’environnement. On comprend l’importance d’évaluer les impacts de leur utilisation et d’améliorer leur profil environnemental. Or ce type d’étude est peu présent dans la littérature. La recherche présentée dans cette thèse comporte l’évaluation des impacts environnementaux en utilisant l’outil d’analyse du cycle de vie (ACV) pour la conception du traitement d’un tissu de polyester (PET) multifonctionnel avec des anthraquinones naturelles. La méthodologie d’éco conception que nous avons appliquée ouvre la voie à une bio-fonctionnalisation des textiles plus respectueuse de l’environnement. Les anthraquinones ont été obtenues par extraction des racines de plantes de garance et constituent le colorant appelé garance. Les trois questions principales abordées lors de ce travail de recherche sont formulées autour de l’utilisation de la garance : (I) Peut-on traiter les tissus de PET avec de la garance pour obtenir des propriétés multifonctionnelles ? (II) Quel est le profil environnemental du procédé de teinture du PET par la garance et comment l’améliorer ? (III) Quels sont les principaux challenges pour l’utilisation de l’ACV dans l’évaluation environnementale du traitement des textiles par des colorants naturels? Nous avons montré que la garance peut être utilisée pour conférer des propriétés multifonctionnelles au PET. Ensuite, nous avons pu orienter notre étude pour améliorer la durabilité des traitements par les procédés de fonctionnalisation à la fois par épuisement ou par foulardage. En s’appuyant sur l’ACV, l’optimisation de la teinture que nous avons réalisée réduit tous les impacts sur l’environnement. Cette étude nous permet d’identifier les challenges qui doivent être surmontés pour que l’ACV puisse contribuer à l’utilisation de bio-molécules pour la teinture des textiles dans le respect des principes de développement durable. Ils concernent le manque de données pour ces travaux de recherche et leur nature interdisciplinaire. Ainsi, en résolvant ces questions, on peut envisager aboutir à une bio- fonctionnalisation des textiles respectueuse de l’environnement. / Den höga miljöpåverkan från textilfärgning och efterbehandling, på grund av hög vattenförbrukning, dess förorening, och ineffektiv användning av energi, är idag välkänt. För att minska miljöpåverkan föreslår forskningsvärlden användning av färgämnen från naturliga resurser. Syftet med att använda dessa är att ge nya attribut till textilier utan att göra avkall på miljömässig hållbarhet. Attribut som ges kan vara färg och/eller andra egenskaper. En nackdel är dock att användningen av bio-baserade färgämnen är inte fri från att belasta miljön. Det blir därför av största betydelse att bedöma denna miljöpåverkan och förbättra miljöprofilen. Sådana studier är dock i allmänhet sällsynta. Studien som presenteras i denna avhandling har inkluderat miljöpåverkans- bedömning, med hjälp av livscykelanalys (LCA), i designprocessen av en multifunktionell polyester (PET) väv via naturliga antrakinoner. Genom att göra så har ett eko-design tillvägagångssätt använts, med avsikt att bana väg för miljömässigt hållbar bio-funktionalisering av textil. Antrakinonerna erhölls från rot extrakt av växten krapp (Rubia tinctorum L.), och hänvisas till som krapp färgämne. Frågeställningar var därför formulerade relaterat till användningen av krapp färgämne. Tre forskningsfrågor har besvarats: (I) Kan krapp färgämne verka multifunktionellt på en PET väv? (II) Hur ser miljöprofilen ut, från färgningsprocessen av PET med krapp färgämne, och hur kan den förbättras? (III) Vilka är de största utmaningarna med att använda LCA för att bedöma miljökonsekvenserna av textilfärgning med växtbaserade färgämnen? Det kan konkluderas att det finns potential för krapp färgämne att verka multifunktionellt på PET. Baserat på uppmuntrande resultat är en rekommendation för det framtida arbetet att fokusera på kvalitén hos de attribut som presenterats och deras förbättringspotential, både i färgning via färgbad och via foulard. LCA driven processoptimering av textilfärgningen förbättrade i varje miljöpåverkans- kategori som studerats. Emellertid har flera utmaningar identifierats som måste  övervinnas för att LCA skall kunna bidra till en hållbar användning av multifunktionella växtbaserade färgämnen för textil. De största utmaningarna är bristen på tillgängliga data i forskningsstadiet och den tvärvetenskapliga forskningsarenan. Det är tänkt att om dessa utmaningar bemästras kan LCA bidra till en hållbar bio-funktionalisering av textil. / <p>Disputationen kan följas via länk i sal U401b, Textilhögskolan, Högskolan i Borås</p> / Erasmus Mundus Joint Doctorate program: Sustainable Management and Design for Textiles
493

Antibacterial activity of plants that are used in the treatment of heartwater in livestock and the isolation and identification of bioactive compounds from Petalidium Oblongifolium and Ipomoea adenioides

Mokwala, Phatlane William 08 June 2007 (has links)
The general antibacterial activity of Drimia delagoansis, Petalidium oblongifolium and Ipomoea adenioides was determined using selected Gram-positive and Gram-negative bacteria. Only extracts or compounds with high antibacterial activity were then tested against the causative agent of heartwater, Ehlrichia ruminantium, since the latter requires specialised culturing conditions. The crude aqueous extract of D. delagoansis had low antibacterial activity with its highest MIC against Gram-negative bacteria being 20.0 mg ml-1 while the crude methanolic extracts of P. oblongifolium and I. adenioides had their highest antibacterial activity against Gram-negative bacteria at MIC's of 5.0 and 10.0 mg ml-1 respectively. Two compounds were isolated and identified from I. adenioides and an unidentified one was isolated from P. oblongifolium. The two compounds from I. adenioides proved to be caffeic acid with MIC's of 0.8 and 1.0 mg ml-1 against Gram-positive and Gram-negative bacteria respectively; and ethyl caffeate with MIC's of 0.4 and 1.0 mg ml-1 against Gram-positive and Gram-negative bacteria respectively. Synergism between the two compounds increased the respective MIC's to 0.4 and 0.2 µg ml-1 against Gram-positive and Gram-negative bacteria. The unidentified compound isolated from P. oblongifolium had a very low MIC of 2.5 µg ml-1 against E. ruminantium. / Thesis (PhD (Botany))--University of Pretoria, 2007. / Plant Science / unrestricted
494

Comportement "in vitro" et "in vivo" de verres composites poreux : assimilation osseuse, explorations physiologiques et physico-chimiques / Behavior "in vitro" and "in vivo" of porous composite glasses : bone assimilation, physiological and physicochemical explorations

Boulila, Salha 30 May 2016 (has links)
L'application des biomatériaux est de plus en plus élargie. Le progrès médical suggère l'utilisation des biomatériaux (verres bioactifs, apatites,..) en tant qu'implants selon le besoin de l'organisme. L'objectif de notre travail est de mettre en évidence l'influence biologique des molécules organiques (bisphosphonates, biopolymères et antibiotiques) incorporés dans des matrices de verres bioactifs. De même, notre étude vise à optimiser les meilleures techniques de synthèse et d'association des verres bioactifs à ces molécules. La détoxification des rats mâles de souche « Wistar » exposés au chlorure de nickel par une apatite synthétique a aussi fait l'objet de ce travail. Suite à une perte osseuse provoquée, nous avons démontré que l'utilisation des antibiotiques associés à des verres bioactifs en tant qu'implants osseux, chez des rattes ovariectomisées, permet d'éliminer certains effets indésirables par voie systémique. Ceci a été mis en évidence par l'évaluation des paramètres biochimiques et histologiques du foie et du rein. Aucune variation significative en comparaison avec ceux du témoin négatif n'a été révélée. L'étude in vitro a montré d'une part que l'introduction du Chitosan et surtout de l'antibiotique dans la matrice vitreuse font augmenter l'activité antibactérienne in vitro. Cette étude in vitro a montré d'autre part que la Ciprofloxacine induit un effet néfaste sur les cellules ostéoblastiques et endothéliales. Cet effet est local lorsqu'il s'agit des expérimentations in vivo. Ceci est mis en évidence lors des évaluations du statut oxydant. Les marqueurs du remodelage osseux, l'histologie de l'os et les paramètres physico-chimiques montrent l'effet retardateur de cet antibiotique sur la dissolution de l'implant et par conséquent sur son ossification. La synthèse par le procédé de sol-gel provoque une bioactivité plus importante que celle obtenue par fusion. La bioactivité des verres bioactifs étudiés diffère selon la molécule introduite. Celle-ci est réduite dans le cas de l'association du Clodronate et de Ciprofloxacine in vitro et in vivo. Alors que, le Polyvinyl Alcohol et surtout le Chitosan font modifier la cinétique de cette bioactivité in vivo. Concernant l'hydroxyapatite, nous avons essayé d'explorer son effet détoxifiant chez des rats reçevant le chlorure de nickel. Nos résultats ont montré que le nickel induit un stress oxydant au niveau du foie, du rein, de la rate et du culot érythrocytaire. Des troubles physiologiques ont été observés chez les rats exposés au nickel. Cependant, l'implantation de l'hydroxyapatite protège les rats intoxiqués par le nickel contre ses effets toxiques en diminuant l'état du stress. Le biomatériau utilisé s'avère efficace pour corriger l'équilibre ferrique et phosphocalcique, protéger les fonctions rénale et hépatique, abaisser le taux du nickel osseux et corriger l'anémie. / The application of biomaterials is increasingly widened. Medical progress suggest the use of biomaterials (bioactive glasses, apatites,..) as implants according to the need of the body. The aim of our work is to highlight the biological influence of organic molecules (bisphosphonates, biopolymers and antibiotics) incorporated into matrix of bioactive glasses. Similarly, our study aims to optimize the best synthesis and combination technique of bioactive glasses to these molecules. The detoxification of male rats strain "Wistar" exposed to nickel chloride by a synthetic apatite also has been the object of this work. Following the bone loss induced, we have demonstrated that the use of antibiotics associated with bioactive glass as bone implants, in ovariectomised rats, eliminates some adverse effects systemic. This has been highlighted by the evaluation of biochemical and histological parameters of liver and kidney. Any significant changes in comparison with those of the negative control was revealed. The in vitro study showed in the one hand that the introduction of Chitosan and especially of the antibiotic in the glass matrix can increase antibacterial activity. This in vitro study showed in the other hand that the Ciprofloxacin induces a negative effect on osteoblastic and endothelial cells. This effect is local when it has been an in vivo experiments. This is highlighted by the oxidative status evaluation. Markers of bone turnover, bone histology and physicochemical parameters show the retarding effect of this antibiotic on the dissolution of the implant and consequently on its bone formation. Synthesis by sol-gel method causes a more important bioactivity than melting. The bioactivity of elaborated bioactives glasses will differ depending on the molecule introduced. It is reduced in the case of combination of Clodronate and Ciprofloxacin in vitro and in vivo. While, Polyvinyl Alcohol and especially Chitosan modify the kinetic of the bioactivity in vivo. Concerning the hydroxyapatite, we tried to explore its detoxifying effect in rats receiving nickel chloride. Our results showed that nickel induces an oxidative stress in the liver, kidney, spleen and red cell pellet. Physiological disorders were observed in rats exposed to nickel. However, implantation of hydroxyapatite protects rats intoxicated by nickel against its toxic effects by decreasing the stress status. The used biomaterial is effective to correct ferric phosphate balance, protect kidney and liver function, reduce level of bone nickel and correct anemia.
495

Synthèse et caractérisations physico-chimiques et biologiques de revêtements implantaires bioactifs / Synthesis and physicochemical and biological characterization of bioactive implant coatings

D'Almeida, Mélanie 15 December 2014 (has links)
L'accès aux soins dentaires est devenu, au cours de ces dernières années, un service de plus en plus demandé par la population. En particulier, la pose d'un implant, destiné à remplacer une dent manquante, en recréant une racine artificielle, devient un acte de plus en plus courant. Une des principales sources de complications entrainant l'échec de la pose d'un implant est une maladie inflammatoire : la péri-implantite. Cette maladie induit la perte des os de soutien dans les tissus entourant l'implant fonctionnel. Actuellement, il n'existe pas d'implant prévenant ces infections bactériennes, seuls des traitements curatifs sont proposés. Le développement d'un traitement antibactérien implantaire apparaît alors comme une solution préventive pertinente pour limiter les complications post-opératoires et représente un défi de santé publique. Pour parvenir à cet objectif, dans ce travail de thèse, plusieurs solutions pour préparer un revêtement implantaire bioactif ont été étudiées et évaluées. Elles sont toutes basées sur le recouvrement d'une surface modèle de titane par un polymère naturel bioactif, le chitosane. Le greffage du biopolymère au substrat a été réalisé via une liaison covalente en utilisant un agent de couplage. Les différentes étapes de la synthèse du revêtement ainsi que ses propriétés biologiques ont été caractérisées à l'aide de techniques d'analyses de chimie de surface, par des études de tenue et de restitution du biopolymère en milieu acide ainsi que par des études in vitro de l'activité antibactérienne et des propriétés biologiques des revêtements. Les résultats de ce travail ont permis de sélectionner le revêtement bioactif possédant les meilleurs propriétés pour l'application visée, notamment en raison de sa tenue en milieu acide et de son activité antibactérienne en présence des bactéries communes / In the past years, population requirement for dental care service increased. More precisely, replacement of missing tooth using dental implant is now a common intervention. As implant provides an artificial root, this procedure is permanent. The failure of the placement procedure is mainly due to an inflammatory disease: peri-implantitis. This disease leads to the death of bone tissues surrounding the dental implant. Today only curative solutions are available, and no implants can prevent bacterial development. It appears that preventing post-surgical complications by designing antibacterial implants is now a public health issue. To achieve this goal, we evaluate in this thesis different solutions to design bioactive implant coatings. We focused our work on coating of a model titanium surface by a bioactive polymer: chitosan. Polymer binding on the substrate is achieved by covalent link using a coupling agent. We described each step of the coating synthesis and characterized its biological properties using both surface chemistry analysis and cell biology techniques. We studied its behavior in an acid environment and analyzed its biological and antibacterial properties in vitro. Results of this work were used to select the bioactive coating with the best properties for the intended application, particularly due to its resistance in acidic condition and its antibacterial activity against common bacteria
496

Estudo da variação nos teores de capsaicinoides, capsinoides, carotenoides, fenólicos totais e capacidade antioxidante de pimentas capsicum chinense em diferentes estádios de maturação e períodos de colheita / Study os variation of capsaicinoids, capsinoids, carotenoids, total phenolic and antioxidant capacity of capsicum chinense pepper in different stages of maturation and harvest periods

Coutinho, Janclei Pereira, 1986- 26 August 2018 (has links)
Orientador: Helena Teixeira Godoy / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-26T20:55:00Z (GMT). No. of bitstreams: 1 Coutinho_JancleiPereira_D.pdf: 3474098 bytes, checksum: cddbd90f9f8705e81a0b46a4513dcb15 (MD5) Previous issue date: 2015 / Resumo: A pimenta é mundialmente utilizada para conferir cor e sabor aos alimentos, podendo ser adicionada na culinária diretamente no alimento, como na indústria em produtos como carnes, sopas, mistura de condimentos, entre outros. O mercado mundial de pimenta está em constante crescimento, onde o mercado asiático aponta como maior produtor e consumidor desse fruto. O Brasil é um produtor/consumidor relativamente pequeno, mas se beneficia no mercado de pimenta, pois exporta essa hortaliça a um bom preço, sendo uma das hortaliças mais lucrativas para o país, mesmo não sendo uma das mais exportadas em termos de volume. A pimenta vem atraindo o interesse não só da indústria de alimentos, mas também da indústria farmacêutica devido a presença de compostos bioativos, dentre os quais destacan-se os capsaicinoides, capsinoides, carotenoides e compostos fenólicos, conferindo a pimenta atividades biológicas interessantes como antioxidante, anti-inlamatória, analgésica, antitumoral, termogênica entre outras. O conhecimento da composição química de pimentas brasileiras ainda é pequeno existindo uma grande quantidade de espécies ainda não caracterizadas. Também são escassos os trabalhos mostrando a variação desses compostos bioativos com diferentes formas de cultivo, bem como com a maturação dos frutos e isso é muito importante quando se visa aumentar ou diminuir a produção de um dado metabólito. Nesse sentido, esse trabalho visa aumentar o conhecimento da composição química de duas variedades de pimentas brasileiras (Cumarí do Pará e Murupí Amarela), bem como o comportamento das classes de compostos acima citadas, com a maturação e período de colheita. Durante o trabalho, foram realizadas etapas de síntese de padrões de capsaicinoides e capsinoides, e isolamento de carotenoides. Para a realização das etapas de otimização da separação destes por cromatografia líquida de ultra alta eficiência (UHPLC) e também uma etapa de otimização da extração de capsinoides pelas técnicas de ultrassom, micro-ondas e flúido pressurizado. Com todos os métodos de separação e extração otimizados, foi realizado o estudo da variação dos capsaicinoides, capsinoides, carotenoides, compostos fenólicos totais e capacidade antioxidante em dois estádios de maturação (comercial e tecnológico) e em dois períodos de colheita (inverno e verão), contribuindo assim para um melhor conhecimento da composição de pimentas Capsicum chinense variedades Cumarí-do-Pará e Murupí Amarela / Abstract: The pepper is widely used to add color and flavor to foods such as directly in cook food as in the industry products such as meats, soups, condiments mix, among others. The world market for pepper is constantly increasing, where the Asian market stands as largest producer and consumer of this fruit, Brazil is a relatively small producer / consumer but benefits the pepper market, as exports pepper at a good price, is one of the most profitable vegetables to Brazil. Pepper have attract the interest not only of the food industry but also the pharmaceutical industry due to the presence of bioactive compounds such as capsaicinoids, capsinoids, carotenoids, phenolic compounds among others, giving pepper biological activities such as antioxidant, anti-inlamatory, analgesic, antitumor and other thermogenic. Knowledge of the chemical composition of Brazilian peppers is still small and there is a lot of not characterized species and are also few studies showing the variation of these bioactive compounds with different forms of cultivation, as well as the maturation and this is very important to increase or decreasing the production of a interesting metabolite. In this sense this paper aims to increase the knowledge of the chemical composition of two varieties of Brazilian peppers, as well as the behavior of these classes of compounds with the maturation and harvest period. Synthesis of standards were performed capsaicinoids and capsinoids, and isolation of carotenoids. With standards produced/isolated, steps of optimization of separation of these compounds were carried out by ultra high performance liquid chromatography (UHPLC), as well as an optimization of capsinoid extraction by techiniques such as ultrasound, microwave and pressurized fluid. With all methods of separation and extraction, was carried out to study the variation of capsaicinoids, capsinoid, carotenoids, phenolic compounds and antioxidant capacity in two ripening stages (mature and immature) and two harvest periods (winter and summer), contributing to a better knowledge of the composition of Capsicum chinense peppers variety "Cumari-do-Pará" and "Murupí Amarela" / Doutorado / Ciência de Alimentos / Doutor em Ciência de Alimentos
497

Atividade antioxidante e composição de oligossacarídeos em subproduto obtido do processamento industrial da goiaba (Psidium guajava) / Antioxidant activity and composition of oligosaccharides in by-product obtained of industrial processing from guava (Psidium guajava)

Silva, Maira Oliveira, 1986- 30 August 2018 (has links)
Orientador: Glaucia Maria Pastore / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-30T23:04:15Z (GMT). No. of bitstreams: 1 Silva_MairaOliveira_M.pdf: 3514110 bytes, checksum: c34d1c9ac53cb0424ed2a213e4e2c9fb (MD5) Previous issue date: 2015 / Resumo: A goiaba (Psidium guajava), uma das frutas tropicais mais consumidas e utilizadas na indústria brasileira, é conhecida como fonte de compostos bioativos relacionados à prevenção de várias doenças no homem, sendo seu subproduto agroindustrial também vinculado a esse benefício. A proposta do presente trabalho foi fornecer dados sobre o subproduto obtido do processamento de goiaba da variedade Paluma, analisando-se distintas metodologias de extração e determinação da capacidade antioxidante dos compostos fenólicos presentes na matriz e identificando a presença de oligossacarídeos, importante prebiótico, bem como sua quantificação, destacando-se a importância de sua aplicação na alimentação. Dois tipos de extração ¿ única com solução hidroetanólica 80% e sequencial com solução hidroacetônica 80% (fenólicos livres), hexano (fenólicos lipossolúveis) e acetato de etila (fenólicos conjugados) ¿ foram utilizadas para a quantificação dos compostos fenólicos, flavonoides e taninos, sendo a avaliação da atividade antioxidante realizada por três ensaios antioxidantes (DPPH ¿ 2,2-difenil-1-picrilhidrazil, ABTS ¿ ácido 2,2'-azinobis-3-etilbenzotiazolina-6-sulfonico e ORAC ¿ capacidade de absorção de oxigênio radical. A identificação e quantificação dos oligossacarídeos foram realizadas em extratos obtidos por três mecanismos ¿ Shaker, Ultra-Turrax e Ultrassom, avaliando-se o mecanismo mais eficiente na recuperação do composto. O subproduto agroindustrial se mostrou uma boa fonte de compostos fenólicos, sendo a extração sequencial de melhor eficiência na extração dos compostos fenólicos (0,56 mg EAG.g-1 ¿ extração única e 2,60 mg EAG.g-1 ¿ extração sequencial), refletindo na maior atividade antioxidante determinada pelos três ensaios quando comparada com a fruta. Os oligossacarídeos identificados nas amostras foram os FOS ¿ fruto-oligossacarídeos (GF2, GF3 e GF4) e os MOS ¿ malto-oligossacarídeos (G3, G4, G5, G6 e G7), sendo maior teor determinado na goiaba. O mecanismo de extração Ultrassom mostrou ser o mais eficiente na recuperação dos oligossacarídeos nas amostras. O estudo indica que o subproduto agroindustrial da goiaba possui grande potencial antioxidante em extratos obtidos por processos sequenciais, merecendo atenção para aplicação em alimentos. As informações apresentadas de oligossacarídeos na goiaba e seu subproduto agroindustrial são uma boa base para um desenvolvimento de banco de dados de composição de alimentos, podendo ser melhores explorados por processo de otimização de extrações para melhor aproveitamento desse prebiótico e aplicação em alimentos. / Abstract: Guava (Psidium guajava), one of the most consumed tropical fruit and used in Brazilian industry, is known as a source of bioactive compounds related to the prevention of various diseases in humans and its agro-industrial by-product also linked to this benefit. The purpose of this study was to provide data on the by-product obtained from the processing from guava of the variety Paluma, analyzing different methodologies of extraction and determination of the antioxidant capacity of phenolic compounds present in the matrix and identifying the presence of oligosaccharides, important prebiotic and its quantification, highlighting the importance of its application in food. Two kinds of extraction ¿ single with hydroethanol 80% solution and sequentially with hydroacetonic 80% solution (free phenol), hexane (soluble phenolic) and ethyl acetate (phenolic conjugates) - were used for the quantification of the phenolic compounds, flavonoids and tannins, and the evaluation of the antioxidant activity performed by three antioxidant assays (DPPH ¿ 2,2-Diphenyl-1-picrylhydrazyl, ABTS ¿ 2,2?-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) and ORAC ¿ oxygen radical absorbance capacity). The identification and quantification of the oligosaccharides were performed on extracts obtained by three mechanisms - Shaker, Ultra-Turrax and Ultrasound, evaluating the most efficient mechanism to recover the compound. The agro-industrial by-product proved to be a good source of phenolic compounds, sequential extraction with an improved efficiency in extraction of phenolic compounds (0.56 mg EAG.g-1 - single extraction and 2.60 mg EAG.g-1 - sequential extraction), reflecting the increased antioxidant activity determined by the three tests when compared with fruit. Oligosaccharides identified in the samples were the FOS ¿ fructooligosaccharides (GF2, GF3 and GF4) and MOS ¿ maltooligosaccharides (G3, G4, G5, G6 and G7), higher specific content in guava. The extraction mechanism Ultrasound showed to be the most efficient in the recovery of oligosaccharides in the samples. The study indicates that the agro-industrial by-product from guava has great potential antioxidant extracts obtained by sequential processes, deserving attention for application in food. The information presented oligosaccharides in guava and its agro-industrial by-product are a good basis for a database development of food composition and can be best exploited by extraction optimization process to better use of prebiotic and application in food / Mestrado / Ciência de Alimentos / Mestra em Ciência de Alimentos
498

Desenvolvimento e avaliação de sorbets probióticos e simbióticos elaborados com polpa de Juçara (Euterpe edulis) / Development and evaluation of probiotic and synbiotic sorbets produced with jussara pulp (Euterpe edulis)

Júlia Fernanda Urbano Marinho 11 March 2016 (has links)
O objetivo deste trabalho foi desenvolver e avaliar diferentes formulações de sorbets probióticos e simbióticos a base de polpa de juçara (Euterpe edulis), de modo a combinar os efeitos benéficos à saúde dos compostos fenólicos deste fruto com os benefícios dos probióticos e prebióticos. Para isso, foram utilizados os microrganismos L. acidophilus e L. paracasei e a fibra polidextrose, além da elaboração de uma amostra controle sem tais elementos para efeito de comparação. Primeiramente, a polpa de juçara pasteurizada utilizada na produção dos sorbets foi avaliada de acordo com suas características físico-químicas e seus compostos bioativos, tendo apresentado resultados adequados para o emprego na matriz alimentícia em questão. Em seguida, os sorbets foram caracterizados através de diversos parâmetros. Assim, a análise centesimal mostrou sorbets com alto índice de carboidratos e baixo valor calórico, enquanto os teores de sólidos solúveis apresentaram-se coerentes em todas as formulações analisadas. Os valores de overrun e densidade aparente relevaram que a incorporação de ar dos sorbets não foi tão elevada quanto de um sorvete lácteo, embora as amostras adicionadas de polidextrose - capaz de mimetizar as propriedades de corpo e espessamento da gordura - tenham obtido resultados mais próximos aos gelados tradicionais. Foram ainda mensurados os efeitos do armazenamento dos produtos a -18 °C durante 120 dias, através de avaliações de pH, coloração instrumental, estabilidade dos compostos fenólicos e antocianinas e viabilidade dos probióticos. O pH das amostras manteve-se constante durante todo o experimento, com valores entre 4,4 e 4,8, enquanto os parâmetros de coloração caracterizaram as amostras como vermelhas e apontaram tendência à perda de luminosidade. Já os polifenóis e antocianinas apresentaram teores elevados, decorrentes da adição da polpa de juçara, sem a ocorrência de degradação destes compostos ao longo da estocagem das amostras sob congelamento. As populações de ambos os microrganismos adicionados apresentaram-se estáveis em cerca de 8 log UFC/ g durante todo o período de armazenamento, o que corresponde a um resultado bastante satisfatório e superior ao recomendado pela legislação brasileira. Por outro lado, a sobrevivência in vitro de tais probióticos quando submetidos aos fluidos gastrointestinais não apresentou resultados adequados para a garantia da funcionalidade destes produtos, com queda de viabilidade superior a 4 ciclos logarítmicos. A aceitabilidade sensorial e intenção de compra apresentaram resultados positivos para todas as formulações, com maior aceitação das amostras probióticas em relação ao controle e menor interesse pelas amostras com adição de prebiótico. Tal resultado demonstra que a incorporação destas bactérias em sorbets de juçara é capaz de melhorar a qualidade do produto, enquanto a adição de polidextrose pode diminuir sua aceitabilidade nas condições empregadas. Em síntese, os sorbets elaborados apresentaram resultados satisfatórios, demonstrando a viabilidade na produção deste tipo de alimento funcional adicionado de probióticos, prebiótico e rico em polifenóis, sendo a combinação de tais elementos capaz de potencializar os efeitos benéficos destes compostos e trazer vantagens fundamentais à microbiota intestinal e à saúde de quem os consome. / This work aimed to develop and evaluate different formulations of probiotic and synbiotic jussara (Euterpe edulis) sorbets in order to combine the beneficial effects of the fenolic compounds of this fruit with the benefits of probiotics and prebiotics. For this, the microorganisms L. acidophilus and L. paracasei and the fiber polydextrose were used and a control sample without such elements was developed for comparison. First, the pasteurized jussara pulp used in the production of sorbets was evaluated according to its physicochemical characteristics and its bioactive compounds and the results obtained showed that it was appropriate for employment in the food matrix. Then, sorbets were characterized by various parameters. The centesimal composition showed high levels of carbohydrates and low caloric value, while the soluble solids content were consistent in all analyzed formulations. The overrun and apparent density values showed that the air incorporated into sorbets was not as high as a dairy ice cream, although the samples with polydextrose - able to mimic the body and thickening properties of fat - have obtained results closer to traditional ice cream. The effects of storage of the products at -18 ° C for 120 days were also measured by pH assessments, instrumental color, stability of phenolic compounds and anthocyanins and viability of probiotics. The pH of the samples remained constant throughout the experiment, with values between 4.4 and 4.8, while the color parameters characterized the samples as red and showed a tendency to lose brightness. The levels of polyphenols and anthocyanins were elevated as a result of the addition of jussara pulp, without degradation of these compounds during storage of samples under freezing. The populations of both added microorganisms were stable at about 8 log CFU/ g throughout the storage period, which is a very satisfactory result and better than the recommended by Brazilian legislation. On the other hand, in vitro survival of the probiotics through simulated gastrointestinal fluids did not present appropriate results to guarantee the functionality of these products, with decrease of viability higher than 4 log cycles. The sensory acceptability and purchase intent showed positive results for all formulations, with greater acceptance of probiotic samples compared to control and less interest in the samples with prebiotic. This result demonstrates that the incorporation of these bacteria in jussara sorbets is able to improve the quality of the product while the addition of polydextrose may decrease the acceptability in conditions employed. In short, sorbets showed satisfactory results, demonstrating the viability of production of functional food with addition of probiotics, prebiotics and rich in polyphenols. The combination of these elements can enhance the beneficial effects and bring fundamental benefits to intestinal microbiota and to health of those who consume them.
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Prospecção de moléculas bioativas em esponjas marinhas da espécie Amphimedon viridis: estudos celulares e moleculares. / Prospection of bioative molecules in Amphimedon viridis sea sponges species: cell and molecular studies.

Marcel Shiniti Urabayashi 14 April 2015 (has links)
A análise química do extrato bruto de esponja marinha é um método clássico de descoberta de novas drogas. Metabólitos secundários e peptídeos são geralmente os resultados neste tipo de pesquisa, utilizando diferentes e consecutivos protocolos de purificação. Neste estudo de uma amostra de extrato aquoso esponja separada numa coluna Sephadex®-G25 foi purificado por HPLC, numa tentativa de isolar uma única molécula. Com uma base de dados de RNA e a análise in silico espera-se que o RNAm pode ser relacionado com a molécula precursora do composto bioativo ou mesmo o seu gene. A dissociação de células a partir da matriz da esponja é um método importante para a extração de RNA optimizado em quantidade e qualidade. Frações extrato bruto do organismo e dados de RNAm a partir de células isoladas da esponja podem ser comparados por uma abordagem de comparação dos dados. Ensaios de MTS foram utilizados para analisar a bioatividade e microscopia confocal foi a principal ferramenta para examinar os danos em células tumorais (T47D). / The chemical analysis of sea sponge crude extract is a classic method in drug discovery. Secondary metabolites and peptides are usually the results in this type of research using different and consecutives purification protocols. In this study a sample of sponge aqueous extract separated in a sephadex-G25 column was purified by HPLC in an attempt to isolate a single molecule. With a RNA databank and in silico analysis is expected that the mRNA may be related with the precursor molecule of the bioactive compound or even its gene. The dissociation of cells from the sponge matrix was an important method to the optimized RNA extraction in quantity and quality. Crude extract fractions of the organism and mRNA data from sponge-isolated cells were obtained to a next step cross-data approach. MTS assays were used to analyze the bioactivity and confocal microscopy was the main tool to scan the damage in tumor cells (T47D).
500

Potencial antioxidante, óleo essencial e atividade antifúngica de plantas de jambu (Spilanthes oleracea), cultivadas sob adubação orgânica e convencional e processamento mínimo de nectarina (Prunus persica var. nectarina) : conservação de suas qualidades e propriedades bioativas /

Borges, Luciana da Silva , 1981- January 2012 (has links)
Orientador: Giuseppina Pace Pereira Lima / Coorientador: Rumy Goto / Banca: Francisco Artes Calero / Banca: Regildo Márcio Gonçalves da Silva / Banca: João Domingos Rodrigues / Banca: Armando Reis Tavares / Resumo: O jambu (Spilanthes oleracea) é uma planta nativa do Brasil, com propriedades químicas importantes. No Estado de São Paulo, a produção de jambu está direcionada para extração do óleo essencial que está sendo fornecido direto para as indústrias de cosméticos, pela sua qualidade farmacológica. No entanto, pesquisas sobre as propriedades antioxidantes dos extratos aquosos e a ação antifúngica do seu óleo essencial são ainda incipientes. Assim, o objetivo geral do primeiro ao terceiro capitulo foram comparar cultivares de jambu produzidos de forma orgânica e convencional, quanto ao desenvolvimento fenológico das plantas (folha e inflorescência), através dos índices morfo-fisiológicos de crescimento, além das substâncias antioxidantes presentes nos extratos aquosos, teores e composição do óleo essencial, bem como sua ação antifúngica. Nos quarto e quinto capitulos, o objetivo foi o uso de radiação UV-C e aplicação de O2 ( 90-100 Kpa) como tratamento capaz de melhorar o potencial de conservação após o processamento mínimo. As características avaliadas no primeiro capitulo foram: Altura de planta, Área foliar, Massa de matéria fresca, Massa de matéria seca, Índice de área foliar (IAF), Razão de Área Foliar (RAF), Área Foliar Específica (AFE), Razão de Peso das Folhas (RPF), Quantidade de água na parte aérea (QAPA), Peso específico foliar (PEF) e Produtividade econômica. No segundo capitulo, avaliou-se: teor de compostos fenólicos, carotenóides, vitamina C e poliaminas, e a atividade da peroxidase, potencial antioxidante, nitrato e nitrogênio; enquanto que, no terceiro capitulo foi extraído e... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The jambu (Spilanthes oleracea) is a native plant of Brazil, with important chemical properties. In São Paulo, the production is directed jambu for extraction of essential oil being supplied direct to the cosmetic, pharmaceutical for its quality. However, research on its antioxidant properties of aqueous extracts and antifungal effect of the essential oil are still incipient. Thus, the overall goal of the first-third chapter were jambu compare cultivars produced under organic and conventional, as the phenological development of plants (leaf and inflorescence), through morphological and physiological indices of growth, in addition to the antioxidants present in extracts aqueous beyond the content and composition of essential oil as well as its antifungal action. In the fourth and fifth chapters, the goal was the use of UV-C radiation and application of O2 ( 90-100 kPa) as a treatment able to improve the conservation value after processing. The characteristics were evaluated in the first chapter: plant height, leaf area, the fresh mass, dry mass, leaf area index (LAI), Leaf Area Ratio (LAR), specific leaf area (SLA), Reason Weight of Leaves (RPF), Amount of water in the shoot (QAPA) , specific leaf weight (PEF) and economic productivity. In the second chapter, we evaluated: content of phenolic compounds, carotenoids, vitamin C and polyamines, and peroxidase activity, antioxidant potential, and nitrate nitrogen, whereas, in the third chapter was... (Complete abstract click electronic access below) / Doutor

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