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Vliv technologie výroby kečupů na retenci nutričně významných látek / The influence of tomato ketchupes production technology on retention of nutritionally significance ingredientsSmolka, Bronislav January 2008 (has links)
The work was focused on the verification of influence of quality of raw material and time-temperature conditions on the retention of nutritionally and sensory important components of the ketchups and other tomato based products. The goal of the theoretical part of this diploma thesis was the optimization of procedure of Czech tomato cultivar selection according to the highest refraction and intensive red colour. The influence of tomato ketchups production technology on retention of nutritionally significant ingredients was observed within the practical part. The samples of ketchups were sampled during different steps of production within one batch in company OTMA Sloko Mařatice. It was ketchup which was preserved by pasteurization in the glass bottle and ketchup which was preserved by hot filing to the plastic bottles. The content of lycopene, ascorbic acid, colour, viscosity, refraction and pH were measured in those samples. Furosine had been chosen as marker of thermal stress on material. The technologies can be compared on the basic of measured values from the view of retention or changes of nutritionally and sensory important components.
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Sledování změn vybraných druhů lokálního ovoce v průběhu mražení / Changes in selected local fruits during freezing.Matějková, Markéta January 2011 (has links)
This diploma thesis was focused on study of low-molecular antioxidants present in various kinds of fruits, namely berries. In theoretical part detailed characterization of antioxidants studied in presented work and their biological effects are introduced. Further, principals of processing and storage of specified species of fruits are discussed. Changes observed during storage of specific fruits are described too. In practical part changes in content of selected antioxidants in berries were followed. As studied material strawberries, raspberries, blueberries, red and black currants were used. All kind of these fruits was stored in fridge for six months using several different kind of processing. Berries were stored as whole fruits, whole osmotically processed fruits by sucrose, raw pulp and sweetened pulp. At first, starting values of selected antioxidant parameters were measured in fresh fruits (ascorbate, total antioxidant activity, total phenolics, catechins and individual flavonoids). After freezing the same parameters were measured regularly in two month periods. As the most suitable method of fruit processing, with regard to antioxidant content, storage of the whole fruits or pulp can be recommended. Content of ascorbate decreased in all forms and species of the processed fruits during all the time of storage. Oppositely, the content of other studied antioxidants exhibited fluctuations or increasing trend. Sensory analysis was proved for the whole fruits and also for whole sweetened fruits.
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Analytická studie redukce rhenistanu amonného vybranými redukčními činidly / Analytical study of reduction of ammonium perrhenate using selected reduction agentsLišková, Jana January 2018 (has links)
This thesis is focused on analysis of reduction of ammonium perrhenate using less frequent reducing agents. Ascorbic acid and acetylhydrazine were chosen as less common reducing agents. Reductions were observed leveraging capillary zone electrophoresis and UV/Vis spectroscopy. Measurements were carried out both in acidic and in basic environments. Reduction of peak area of ammonium perrhenate was observed using capillary zone electrophoresis after addition of reducing agent. Rate of absorption of ammonium perrhenate was monitored with UV/Vis spectroscopy. Furthermore, the possibility of shifting the equilibrium of the reaction to the benefit of the reduction products was monitored by the addition of the complexing agent. Py- rogallol (benzene-1,2,3-triol) was used as the ligand and acetylhydrazine was selected as the reducing agent. The reduction was monitored by capillary zone electrophoresis. The identity of the resulting complex was confirmed with ESI/MS. Keywords rhenium, rhenium complexes, ascorbic acid, acetylhydrazine, capillary zone electrophore- sis, UV/Vis spectroscopy, mass spectrometry
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Uticaj vrednosti pH pufera i vrste anjona na brzinu oksidacije L-askorbinske kiseline / Influence of Buffer рН Value and Anion Туре on L-Ascorbic Acid Oxidation RateKolarov Ljiljana 25 May 1999 (has links)
<p><strong>Apstrakt je obrađen tehnologijama za optičko prepoznavanje teksta (OCR).</strong></p><p>U radu je spektrofotometrijski ispitivana brzina oksidacije L-askorbinske kiseline. Tok reakcije je praćen snimanjem UV apsorpcionih spektara termostatiranih rastvora L-askorbinske kiseline u puferima različitih vrednosti rN: acetatnom (4-6). fosfatnom (5-8). fosfatno-citratnom (6-8), boratnom (8-11). glicinskom (9-11) i univerzalnom (4-11) !zveden je jednostavan oblik kinetičke jednačine reakcije višeg i razlomljenog reda. Dobijena jednačina je univerzalna, jer obuhvata jednačine nultog, prvog, drugog, trećeg i razlomljenog reda izračunate su vrednosti reda reakcije i one variraju sa promenom vrednosti rN unutar jednog puferskog sistema. Veza između vrednosti konstanti brzine oksidacije L-askorbinske kiseline i vrednosti rN ispitivanih pufera je linearna do vrednosti rN=10.00. Vrednosti koeficijenta pravca prave su različite za ispitivane pufere. Vrsta anjona prisutna u puferu kao i prisusutvo jona metala u korišćenim hemikalijama utiču na vrednosti konstante brzine oksidacije L-askorbinske kiseline i one su različite u raznim puferima istih vrednosti rN. Vrednosti konstante brzine oskidacije L-askorbinske kiseline su največe u univerzalnom puferu pri svim vrednostima rN. Prisutna smeša anjona manje utiče na oksidaciju L-askorbinske kiseline nego pojedinačni anjoni, verovatno zbog među- sobnih interakcija.</p> / <p><strong>Abstract was processed by technology for Optical character recognition (OCR).</strong></p><p>The paper deats with the spectrophotometric study of L-ascorbic acid oxidation rate. The course of reaction has been observed by recording the UV absorption spectra of thermostated solution of L-ascorbic acid in buffers with different рН values: acetate (4-6), phosphate (5-8), phosphate-citrate (6-8), borate (8-11), glycine (9-11) and universal (4-11). A simple form of kinetic eguation of higher and fractional order reaction has been observed. The obtained eguation is universal as it comprises the eguations of zero, first, second, third and fractional order. The reaction order values have been calculated and they vary with change of рН values within each buffer system. The relation between the values of L-ascorbic acid oxidation rate constants and рН value of the studied buffers is linear up to рН value = 10.00. The straight line stopes are different for investigated buffers. The anion type present in a buffer as wett as the presence of metal ions in applied chemicals affect the values of L-ascorbic acid oxidation rate constant and they are different in different buffers with the same рН values. The values of L-ascorbic acid oxidation rate constant are the highest in the universal buffer at all рН values. The present anion mixture affects the L-ascorbtc acid oxidation to a tesser degree than single anions, presumabty due to mutuat interactions.</p>
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Stanovení vybraných nutričních faktorů v některých druzích minoritního ovoce / Vitamin CJuráňová, Jana January 2013 (has links)
The theme of this diploma thesis is an assessment of given nutritional parameters in selected kinds of lesser known fruits, specifically 10 varieties of sea buckthorn (Hippophae rhamnoides L.), 12 varieties of cornelian cherry (Cornus mas L.) and 6 varieties of blue honeysuckle (Lonicera caerulea var. kamtschatica). Harvests of two consecutive years (2011 and 2012) were analyzed in the case of blue honeysuckle. The theoretical part was focused on historical, morphological, taxonomic and nutritional aspects of individual plants and food or pharmaceutical utilization. The considerable part of the thesis is devoted to the characterization and the possibilities of determining the contained substances, namely ascorbic acid and polyphenolic compounds, especially anthocyanins. The content of the experimental part was a description of the methods and the results of the analysis of total solids, titratable acidity, total phenolics, total anthocyanins and ascorbic acid in fruits of the selected varieties of the above mentioned fruit species. Based on the measured results, the different varieties of fruits were compared to each other and evaluated.
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Исследование антиоксидантных свойств витаминных препаратов различной гидрофильности : магистерская диссертация / Investigation of the antioxidant properties of vitamin preparations of various hydrophilicityТимина, Д. С., Timina, D. S. January 2021 (has links)
Объектами исследования являются витамины разной гидрофильности и витаминосодержащие препараты в таблетированной форме. Цель работы: исследование антиоксидантных свойств витаминных препаратов различной гидрофильности. Исследована антиоксидантная емкость модельных растворов и смесей антиоксидантов разной гидрофильности потенциометрическим методом; подобраны оптимальные условия для проведения анализа липофильного и гидрофильного соединений в совместном присутствии; исследованы фармацевтические препараты в таблетированной форме, содержащие витамины С и Е; проведено сравнение результатов с методом Фолина-Чокальтеу. Рассмотрена возможность применения методики определения АОЕ в условиях микрофлюидного устройства. / The objects of research are vitamins of different hydrophilicity and vitamin-containing preparations in tablet form. Purpose of the work: study of the antioxidant properties of vitamin preparations of various hydrophilicity. The antioxidant capacity of model solutions and mixtures of antioxidants of different hydrophilicity was investigated by potentiometric method; the optimal conditions were selected for the analysis of lipophilic and hydrophilic compounds in their joint presence; investigated pharmaceutical preparations in tablet form containing vitamins C and E; the results are compared with the Folin-Chocalteu method. The possibility of using the method for determining AOE in a microfluidic device is considered.
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Causes and Consequences of A Glutamine Induced Normoxic HIF1 Activity for the Tumor MetabolismKappler, Matthias, Pabst, Ulrike, Weinholdt, Claus, Taubert, Helge, Rot, Swetlana, Kaune, Tom, Kotrba, Johanna, Porsch, Martin, Güttler, Antje, Bache, Matthias, Krohn, Knut, Bull, Fabian, Riemann, Anne, Wickenhauser, Claudia, Seliger, Barbara, Schubert, Johannes, Al-Nawas, Bilal, Thews, Oliver, Grosse, Ivo, Vordermark, Dirk, Eckert, Alexander W. 25 January 2024 (has links)
The transcription factor hypoxia-inducible factor 1 (HIF1) is the crucial regulator of
genes that are involved in metabolism under hypoxic conditions, but information regarding the
transcriptional activity of HIF1 in normoxic metabolism is limited. Different tumor cells were treated
under normoxic and hypoxic conditions with various drugs that affect cellular metabolism. HIF1ff
was silenced by siRNA in normoxic/hypoxic tumor cells, before RNA sequencing and bioinformatics
analyses were performed while using the breast cancer cell line MDA-MB-231 as a model. Differentially
expressed genes were further analyzed and validated by qPCR, while the activity of the metabolites
was determined by enzyme assays. Under normoxic conditions, HIF1 activity was significantly
increased by (i) glutamine metabolism, which was associated with the release of ammonium, and
it was decreased by (ii) acetylation via acetyl CoA synthetase (ACSS2) or ATP citrate lyase (ACLY), respectively, and (iii) the presence of L-ascorbic acid, citrate, or acetyl-CoA. Interestingly, acetylsalicylic
acid, ibuprofen, L-ascorbic acid, and citrate each significantly destabilized HIF1ff only under normoxia.
The results from the deep sequence analyses indicated that, in HIF1-siRNA silenced MDA-MB-231
cells, 231 genes under normoxia and 1384 genes under hypoxia were transcriptionally significant
deregulated in a HIF1-dependent manner. Focusing on glycolysis genes, it was confirmed that HIF1
significantly regulated six normoxic and 16 hypoxic glycolysis-associated gene transcripts. However,
the results from the targeted metabolome analyses revealed that HIF1 activity affected neither the
consumption of glucose nor the release of ammonium or lactate; however, it significantly inhibited
the release of the amino acid alanine. This study comprehensively investigated, for the first time,
how normoxic HIF1 is stabilized, and it analyzed the possible function of normoxic HIF1 in the
transcriptome and metabolic processes of tumor cells in a breast cancer cell model. Furthermore, these
data imply that HIF1 compensates for the metabolic outcomes of glutaminolysis and, subsequently,
theWarburg effect might be a direct consequence of the altered amino acid metabolism in tumor cells.
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Variation of Fruit Quality Traits in Apricot as Sources for Nutraceutical BreedingGómez Martínez, Helena 23 December 2021 (has links)
Tesis por compendio / [ES] Actualmente, hay un progresivo interés por una dieta equilibrada y saludable, rica en frutas y verduras con un efecto positivo en la salud y, particularmente, con alto contenido en antioxidantes. Paralelamente existe una demanda, por parte del consumidor, de fruta de alta calidad que tenga un sabor equilibrado y que recuerde a las variedades tradicionales. Todo ello ha propiciado que los programas de mejora genética también tengan como objetivo la mejora de la calidad de la fruta, tanto en propiedades fisicoquímicas del fruto como de su perfil nutricional. Desde este punto de vista, el albaricoque es un fruto muy completo ya que es una fuente extraordinaria de fibra, vitaminas, compuestos fenólicos y ácidos orgánicos. Sus propiedades hacen posible su consumo tanto en fresco o como procesado, lo que es aprovechado por las industrias agroalimentaria, farmacéutica y cosmética para la elaboración de una amplia variedad de productos.
En el Instituto Valenciano de Investigaciones Agrarias (IVIA) se está llevando a cabo un programa de mejora para la obtención de nuevas variedades de albaricoquero que, además de solucionar factores que afectan directamente a la producción, como son la autocompatibilidad o resistencia a Sharka, también tiene por objetivo la mejora de la calidad de la fruta. Como primer paso en todo programa de mejora, en este trabajo se han identificado fuentes de variación entre la colección de accesiones del banco de germoplasma del IVIA, quedando detallada la composición del perfil para los principales azúcares, ácidos orgánicos, compuestos fenólicos y de vitamina C. Además, se ha identificado una mayor concentración de compuestos en la piel del fruto que en su pulpa, lo que hace de este tejido una fuente de compuestos de interés para la industria.
Por otro lado, para un mejor conocimiento del control genético del metabolismo de azúcares, se estudió la expresión de los genes clave implicados en esta ruta (SUS, SPS y FK), relacionados con QTLs previamente descritos en materia de sólidos solubles. Además, también se reforzó el estudio con el correspondiente análisis filogenético entre diferentes especies, observándose el grado de conservación entre las mismas y confirmándose el alto grado de sintenia en el género Prunus.
Con relación a los compuestos fenólicos, se ha analizado la expresión de genes implicados en puntos críticos de la ruta metabólica (DRF, PAL y FLS). Nuestros resultados revelaron que las variedades más rojizas se asocian a una mayor expresión de ParDFR y ParPAL2, así como también que las diferencias de expresión entre parálogos podría deberse a la presencia de un BOXCOREDLPAL, relacionado también con los genes implicados en la síntesis de antocianinas (ParDFR, ParFLS2 y ParPAL2). Paralelamente, también se estudió el efecto genético que ejerce sobre su descendencia la variedad 'Goldrich', uno de los principales genitores empleados en el programa de mejora para la introgresión de la resistencia a Sharka, concluyendo que favorece la concentración de neoclorogénico y clorogénico, así como en la expresión génica de ParPAL1. / [CA] Actualment, hi ha un progressiu interés per una dieta equilibrada i saludable, rica en fruites i verdures amb un efecte positiu en la salut i, particularment, amb alt contingut en antioxidants. Paral·lelament existeix una demanda, per part del consumidor, de fruita d'alta qualitat que tinga un sabor equilibrat i que recorde a les varietats tradicionals. Tot això, ha propiciat que els programes de millora genètica també tinguen com a objectiu la millora de la qualitat de la fruita, tant en propietats fisicoquímiques del fruit com del seu perfil nutricional. Des d'aquest punt de vista, l'albercoc és un fruit molt complet ja que és una font extraordinària de fibra, vitamines, compostos fenòlics i àcids orgànics. Les seues propietats fan possible el seu consum tant en fresc com processat, sent també aprofitat per les indústries agroalimentària, farmacèutica i cosmètica per a l'elaboració d'una àmplia varietat de productes.
A l'Institut Valencià d'Investigacions Agràries (IVIA) s'està duent a terme un programa de millora per a l'obtenció de noves varietats d'albercoquer que, a més de solucionar factors que afecten directament la producció, com són l'autocompatibilitat o resistència a Sharka, també té per objectiu la millora de la qualitat de la fruita. Com a primer pas en qualsevol programa de millora, en aquest treball s'han identificat fonts de variació entre la col·lecció d'accessions del banc de germoplasma de l'IVIA, quedant detallada la composició del perfil per als principals sucres, àcids orgànics, compostos fenòlics i de vitamina C. A més, s'ha identificat una major concentració de compostos en la pell del fruit que en la seua polpa, convertint aquest teixit en una font de compostos d'interés per a la indústria.
D'altra banda, per a un millor coneixement del control genètic del metabolisme de sucres, es va estudiar l'expressió dels gens clau implicats en aquesta ruta (SUS, SPS i FK), relacionats amb QTLs prèviament descrits en matèria de sòlids solubles. A més, també es va reforçar l'estudi amb la corresponent anàlisi filogenètica entre diferents espècies, observant-se el grau de conservació entre les mateixes i confirmant-se l'alt grau de sintenia al gènere Prunus.
En relació amb els compostos fenòlics, s'ha analitzat l'expressió de gens implicats en punts crítics de la ruta metabòlica (DRF, PAL i FLS). Els nostres resultats van revelar que les varietats més vermelles s'associen a una major expressió de ParDFR i ParPAL2, així com també que les diferències d'expressió entre paràlogs podria deure's a la presència d'un BOXCOREDLPAL, relacionat també amb els gens implicats en la síntesi de antocianines (ParDFR, ParFLS2 i ParPAL2). Paral·lelament, també es va estudiar l'efecte genètic que exerceix sobre la seua descendència la varietat 'Goldrich', un dels principals genitors empleats al programa de millora per a la introgressió de la resistència a Sharka, concloent que afavoreix la concentració de neoclorogènic i clorogènic, així com en l'expressió gènica de ParPAL1. / [EN] Nowadays, there is a growing interest in a balanced and healthy diet, rich in fruit and vegetables with a positive effect on health and, particularly, with high antioxidant content. Simultaneously exists a consumer demand for high quality fruit with a balanced flavour and reminiscent of traditional varieties. As a result, breeding programmes are also aimed at improving the quality of the fruit, both in terms of the physicochemical properties of the fruit and its nutritional profile. From this point of view, the apricot is a complete fruit as far it is an extraordinary source of fibre, vitamins, phenolic compounds, and organic acids. Apricot properties make it possible to consume fruits both fresh and processed, which is exploited by the agri-food, pharmaceutical and cosmetic industries for the production of a wide variety of products.
At the Instituto Valenciano de Investigaciones Agrarias (IVIA) a breeding program is carrying out to obtain new apricot varieties but also to solve factors that directly affect production, such as self-compatibility or resistance to Sharka, but also is aimed to improve fruit quality. As the first step in any breeding program, this work has identified sources of variation among the collection of accessions in the IVIA's apricot collection, detailing the composition profiles for the main sugars, organic acids, phenolic compounds, and vitamin C. In addition, a higher concentration of compounds has been identified in the peel than in the flesh, which makes this tissue a source of compounds of interest for the industry.
On the other hand, for a better knowledge of the genetic control of sugar metabolism, the expression of the key genes involved in this pathway (SUS, SPS and FK), related to QTLs previously described in soluble solids, was studied. In addition, the study was also supported with the corresponding phylogenetic analysis among different species, revealing the level of conservation among them and confirming the high level of synteny in the genus Prunus.
Regarding phenolic compounds, the expression of genes involved in critical points of the metabolic pathway (DRF, PAL and FLS) was analysed. Our results revealed that the red-blushed accessions are associated with a higher expression of ParDFR and ParPAL2, and the expression differences among paralogues could be due to the presence of a BOXCOREDLPAL, also related to genes involved in anthocyanin biosynthesis (ParDFR, ParFLS2 and ParPAL2). Simultaneously, the genetic effect in the offspring of 'Goldrich', one of the main genitors used at the breeding program for the introgression of Sharka resistance, was also studied. Results revealed that it improves the concentration of neochlorogenic and chlorogenic acids, as well as the genetic expression of ParPAL1. / Este trabajo ha sido posible gracias a la ayuda predoctoral FPI-INIA-2015, del Instituto Nacional de
Investigación y Tecnología Agraria y Alimentaria (INIA), bajo el proyecto FPI2015-0042 con la
denominación ‘CPD2015-0245 Mejora sostenible de albaricoquero y melocotonero’ y desarrollado en
el Instituto Valenciano de Investigaciones Agrarias (IVIA), dependiente de la Generalitat Valenciana. / Gómez Martínez, H. (2021). Variation of Fruit Quality Traits in Apricot as Sources for Nutraceutical Breeding [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/178973 / Compendio
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Etude et fonctionnalisation de protéines végétales en vue de leur application en microencapsulation / Study and functionalization of vegetable proteins and their application in microencapsulationNesterenko, Alla 05 December 2012 (has links)
Les protéines extraites des végétaux sont des matériaux relativement peu coûteux, non toxiques, biocompatibles et biodégradables. Elles représentent une bonne alternative aux protéines d’origine animale et aux polymères dérivés du pétrole. Dans le cadre de cette étude, les protéines extraites de graines de soja et de tournesol ont été utilisées en tant que matériaux enrobants pour la microencapsulation de la matière active hydrophobe (α-tocophérol) ou hydrophile (acide ascorbique) par le procédé d’atomisation. Les protéines de soja sont largement utilisées dans les applications alimentaires et non-alimentaires, notamment en microencapsulation. Elles sont donc étudiées dans ce travail comme matériau enrobant de référence. Les protéines de tournesol n’ont quant à elles pas d’application industrielle concrète, si ce n’est sous la forme de tourteaux dans l’alimentation animale. C’est pourquoi il nous semble pertinent de trouver des nouvelles voies de valorisation pour ce coproduit d’origine agricole. Plusieurs modifications des protéines, telles que l’hydrolyse enzymatique, l’acylation, la réticulation enzymatique et la cationisation ont été étudiées dans le but d’améliorer les propriétés encapsulantes du matériau enrobant. Dans le contexte de la chimie verte, toutes les modifications ont été effectuées sans utilisation de solvants organiques ni de catalyseurs chimiques. L’influence des modifications chimiques et enzymatiques des protéines, et des paramètres du procédé (pression d’homogénéisation, ratio matériau enrobant/matière active et concentration en protéines) sur les différentes caractéristiques des préparations liquides et des microparticules (viscosité, taille des gouttelettes dans le cas des émulsions, morphologie et taille des microparticules), ainsi que sur les paramètres liés au procédé d’atomisation (rendement et efficacité de microencapsulation) a été particulièrement étudiée au cours de ce travail. Les résultats obtenus confirment que l’extrait protéique de tournesol est tout à fait pertinent comme matériau enrobant et permet d’obtenir des efficacités de microencapsulation significativement plus élevées par rapport à celles obtenues avec l’extrait protéique de soja. / Proteins extracted from vegetables are relatively low-cost, non-toxic, biocompatible and biodegradable raw materials. They represent a good alternative to animal-based proteins and petroleum-extracted polymers. In this study, proteins derived from soybean and sunflower seeds were used as wall materials for microencapsulation of hydrophobic (-tocopherol) or hydrophilic (ascorbic acid) active material by spray-drying technique. Soybean proteins are widely used in food and non-food applications, especially in microencapsulation. They were studied in this work as wall material of reference. Sunflower proteins are not actually used in industrial application, but only in the form of oil-cake for animal feeding. That’s why new ways of valorization of this agricultural by-product should be investigated. Several proteins’ modifications such as enzymatic hydrolysis, acylation, cross-linking and cationization were studied in order to improve encapsulating properties of wall material. In the context of green chemistry, all the modifications and preparations were performed without use of organic solvents and chemical catalysts. The effect of protein chemical and enzymatic modifications, and process parameters (homogenization pressure, wall/core ratio and protein concentration) on different characteristics of liquid preparations and microparticles (viscosity, emulsion droplet size, microparticle size and morphology) and on parameters related to the spray-drying process (yield and efficiency of microencapsulation) was particularly investigated in this study. The obtained results confirmed that sunflower proteins are quite suitable as encapsulating agent and provide the microencapsulation efficiencies significantly higher compared to those obtained with soy proteins.
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Remoção de mercúrio e arsênio em cação-azul, Prionace glauca / Mercury and arsenic removal in blue-shark, Prionace glaucaMacedo, Luciene Fagundes Lauer 30 April 2010 (has links)
Os cações são importantes recursos pesqueiros que podem apresentar concentrações de mercúrio (Hg) e arsênio (As) muitas vezes acima do limite de tolerância, o que os tornam impróprios como alimento. No meio aquático estes contaminantes são convertidos em espécies orgânicas, em especial metilmercúrio (MeHg) e arsenobetaína (AB), respectivamente. O MeHg é neurotóxico, sendo o sistema nervoso em desenvolvimento o mais susceptível. A AB é pouco tóxica, no entanto, o As inorgânico está envolvido em processos de estresse oxidativo, mutagênese e principalmente carcinogênese. Neste trabalho, foi avaliada a eficiência da cisteína na remoção de Hg, a ocorência de As total e inorgânico, e a redução de sua concentração com o emprego de borohidreto de sódio e de preparos para o consumo. A redução máxima de Hg, de 59,4%, com cisteína a 0,5% em pH 5,0, não foi reproduzida quando pretendida a reutilização da solução do aminoácido, importante do ponto de vista prático. O cação-azul continha elevados níveis de As total, 1,98 a 22,56 µg/g (base úmida), que foram removidos com borohidreto de sódio em 99%, demonstrando a alta potencialidade do método usado. O As inorgânico, presente na quantidade média de 0,0086 µg/g (base úmida), foi reduzido em 27,7%. O preparo para o consumo, por cozimento em água, do cação-azul em cubos (1-2 cm3), resultou em maior remoção de As total, de 65,9 a 71,2%; no cação grelhado a redução foi de 55,4 a 60,2%. As amostras, grelhadas ou cozidas, adicionadas de sal e limão enriquecido com ácido ascórbico, e as grelhadas contendo sal e sal com limão, apresentaram redução na concentração de As inorgânico de 30,1 a 42,8%. / The shark are important fishery resources that may have concentrations of mercury (Hg) and arsenic (As) often above the limit of tolerance, which makes them unsuitable as food. In the aquatic environment these contaminants are converted to organic species, particularly methylmercury (MeHg) and arsenobetaína (AB), respectively. The MeHg is neurotoxic, and the developing nervous system more susceptible. AB is slightly toxic, however, the inorganic As is involved in processes of oxidative stress, mutagenesis and carcinogenesis mainly. In this study, we evaluated the efficiency of cysteine to remove mercury, the occurrence of the total and inorganic As, and the reduction of their concentration with the use of sodium borohydride and preparations for consumption. The maximum reduction of Hg, 59.4%, with 0.5% cysteine at pH 5.0, was not reproduced when you want to reuse the solution of the amino acid, important practical point of view. The blue-shark contained high levels of the total As, 1.98 to 22.56 µg/g (wet weight), which were removed with sodium borohydride in 99%, demonstrating the high potential of the method used. The inorganic As, present in the average amount of 0.0086 µg/g (wet weight) was reduced in 27.7%. Preparation for consumption by baking in water, the blue-shark into cubes (1-2 cm3) resulted in greater removal of the total As, 65.9 to 71.2%; in the grilled shark the reduction was 55,4 to 60.2%. The samples, grilled or baked, added salt and lemon enriched with ascorbic acid, and the grilled containing salt and salt with lemon, presented reduction in the concentrations of inorganic As from 30.1 to 42.8%.
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