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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.
1

Změny v obsahu proteinů gliadinové frakce u čtyř odrůd pšenice při různých teplotách a stresu suchem. / Changes in gliadin content in four varieties of wheat at different temperatures and drought stress.

Cigánková, Michaela January 2019 (has links)
This diploma thesis deals with an influence of increasing temperature and water shortage on the content of gliadin proteins in four varieties of wheat: Bohemia, Pannonia, Tobak and RGT Reform. Samples were cultivated at 26, 29, 32, 35, 39 and 41 ° C. Due to the lack of culture samples at 41 ° C, these samples were not used for our experiment. Cultivation took place during flowering with sufficient moisture (with soil moisture higher than 70%) or under drought stress (with humidity below 30%). The A-PAGE method was used to separate gliadin fractions. Quantification was performed by computer densitometry. Significant influence of water availability on gluten protein content was found. The lack of moisture in the stress environment caused a relative increase in gliadin fractions compared to conventional conditions, especially in the Pannonia and RGT Reform varieties. The Pannonia and RGT Reform varieties responded most to the temperature, while Bohemia. The Tobak variety responded to the temperature in interaction with water scarcity. Due to the rising temperature, virtually all gliadin fractions in the Pannonia and RGT Reform varieties increased. The effect of drought often manifests itself in interaction with the influence of temperature. The most dramatic effect was the drought in interaction with temperature in the Tobak variety, where the gliadin content increased. In general, the temperature and drought were most affected by -gliadin fractions of all four varieties of wheat.
2

Změny v obsahu gliadinových frakcí bílkovin u dvou genotypů ozimé pšenice s rozdílnou délkou vegetační doby v závislosti na dusíkatém hnojení v interakci se suchem. / Changes in the content of gliadin protein fractions in two genotypes of winter wheat with different lengths of vegetation time depending on nitrogen fertilization with drought interaction.

Francová, Marie January 2019 (has links)
In this diploma thesis the influence of the nitrogen fertilization and drought on the change in the content of gliadin protein fractions in two genotypes of winter wheat Avenue and Tobac was studied. These two genotypes differ in vegetation time length. Half of the plants were fertilized using nitrogen fertilizer at 200 kg N/ha. One third of the plants were cultured under the conditions of early drought (in bloom season), other one third was grown under the conditions of of late drought (grain filling season), and last third was grown under the conditions of natural irrigation. Individual gliadin fractions were separated by using A-PAGE method and their content quantified by computer densitometry. Our results have shown increase in gliadin fractions content after nitrogen fertilization. Early drought itself caused significant increase in the levels of -gliadin fractions in Tobac genotype. Early and late drought in combination with nitrogen fertilization increased levels of gliadin fractions in Tobac genotype. Early drought in combination with nitrogen fertilization had no effect on Avenue genotype, except of -gliadin fractions which decreased significantly. Late drought in combination with nitrogen fertilization caused significant increase in gliadin content in Avenue genotype. The highest increase in gliadin content was observed in fraction -5 of the Tobac variety during interaction nitrogen fertilization with late drought.
3

Změny v obsahu gliadinových frakcí bílkovin u dvou genotypů ozimé pšenice s rozdílnou délkou vegetační doby v reakci na zvýšenou koncentraci oxidu uhličitého. / Changes in the content of gliadin protein fractions in two genotypes of winter wheat with different lengths of vegetation time in response to an elevated concentration of carbon dioxide.

Janíčková, Vlasta January 2019 (has links)
This diploma thesis deals with an influence of elevated concentration of carbon dioxide (700 mol·mol-1) on the protein content of gliadin fraction in winter wheat (Triticum aestivum) early var. Avenue and late var. Tobac. To separate gliadin, the A-PAGE method was used, proteins were quantified by computer densitometry. Signitificant influence of genotype on the gliadin fraction of the gluten proteins was found. Due to the increased concentration of CO2, the content of the gliadin fraction of the Avenue variety was reduced, while the content of the gliadin fraction of the Tobac variety increased. Effect of elevated CO2 concentration was at var. Avenue showed a significant difference in total content of gliadin fraction and fraction 1,2-gliadins. A significant difference was found in the var. Tobac only in the fraction 1,2-gliadin.
4

Vliv zvýšené koncentrace oxidu uhličitého a dusíkatého hnojení na obsah proteinů gluteninové a gliadinové frakce u ozimé pšenice / Impact of elevated carbon dioxide concentration and nitrogen nutrition on protein content of glutenin and gliadin fraction in winter wheat

Chadimová, Klára January 2016 (has links)
The present study investigates effects of elevated atmospheric carbon dioxide concentration, different nitrogen fertilization levels, drought and UV radiation on protein content of wheat gluten fractions glutenins and gliadins. Winter wheat cultivar Bohemia was grown under ambient CO2 concentration (AC; 400 mol CO2.mol-1) and elevated CO2 concentration (EC; 700 mol CO2.mol-1). Half of the samples was fertilized with 200 kg N.ha-1 (N+) and the other part stayed unfertilized (N–). Other environmental factors were UV radiation exclusion (UV–, UV+) and drought (DRY, WET). Gliadins were separated by A-PAGE, glutenins by SDS-PAGE. Proteins were quantified by computer densitometry. Nitrogen fertilization caused an significat increase of gliadins and glutenins. While some gliadins subfractions were significantly lowered by drought, HMW glutenin subunits showed significant increase. UV radiation exclusion resulted in significant decrease of some gliadin subfractions and glutenin subunits. CO2 enrichment caused significant increase of glutenin subfractions HMW 1 and 2, while gliadin subfractions -5 1 and 1 were significantly decreased by elevated CO2 concentration.
5

Vliv zvýšené koncentrace oxidu uhličitého na obsah proteinů gliadinové frakce u ozimé pšenice / Impact of elevated carbon dioxide concentration on protein content of gliadin fraction in winter wheat

Hamříková, Dominika January 2015 (has links)
In this diploma thesis protein content of gliadin fractions in winter wheat (Triticum aestivum) var. Bohemia was studied. The crop was cultivated in conditions with ambient (AC) and elevated (EC; 700 mol•mol-1) carbon dioxide concentration. Moreover, half of the samples was fertilized with nitrogen in an amount of 200 kg•ha-1. Other observed environmental factors were drought and UV radiation. The gliadin proteins were separated by A PAGE method and quantified by computer densitometry. Generally the protein content within , and gliadin fractions varied, while the protein content of gliadins remained unchanged or almost unchanged. Clearly the nitrogen fertilization had the most pronounced impact on the gliadin protein content and it significantly increased the protein content in wheat grain. Most subfractions reacted in conditions of AC, drought and without UV radiation and in conditions of EC with natural rainfall and UV radiation. The interaction of nitrogen fertilization with UV radiation (AC, drought) was significant and so was the interaction of nitrogen fertilization excluding UV radiation (EC, drought). The interaction of nitrogen fertilization and natural rainfall significantly increased the protein content in conditions of AC without UV radiation and in conditions of EC with UV radiation. EC alone and the interaction of EC with other factors had only a small impact. The impact was the most pronounced in interaction with nitrogen fertilization. EC with nitrogen fertilization (drought without UV radiation) increased the gliadin protein content and EC excluding nitrogen fertilization (drought and natural rainfall with UV radiation) decreased the protein content.
6

Vliv teploty a sucha na obsah proteinů gliadinové a gluteninové frakce u čtyř odrůd pšenice / Impact of temperature and drought on gliadins and glutenins contents in four varieties of wheat

Tomasz, Teresa January 2017 (has links)
This diploma thesis deals with an influence of high temperature and water shortage on the protein content of gliadin and glutenin fractions in four varieties of winter wheat: Bohemia, Tobak, Pannonia and var. Syria with designation S46 (IG142780). The crop was grown at 26, 29, 32, 35, 38 and 41 °C during anthesis under control irrigation treatment (with soil moisture higher than 70 %) or under drought stress (with soil moisture lower than 30 %). To separate gliadins, the A-PAGE method was used, and glutenins were separated by SDS-PAGE method. Proteins were quantified by computer densitometry. Significant influence of genotype on the gluten proteins was found. Variety Pannonia has high content of -, 5-gliadins, LMW and HMW glutenins, but low content of other gliadin fractions. It was the opposite in the other varieties. Due to temperature, as well as drought, there was an increase in the content of all gluten fractions, especially of HMW glutenins, 1,2-gliadins and total gliadins. The largest increase in the gluten fractions due to drought was observed in Syria variety. In other varieties simultaneous exposure to drought and heat caused decrease in gliadin content, but increase in glutenin content. Drought at high temperatures reduced gliadin-to-glutenin ratio, mostly in Bohemia variety. This ratio has increased due to the temperature, especially in Tobak variety. For Syria variety, no effect of stress conditions was found on gliadin-to-glutenin ratio.
7

Vliv dusíkatého hnojení a sucha na obsah proteinů gliadinové frakce u ozimé pšenice / Impact of nitrogen fertilization and drought on gliadins content in winter wheat

Odstrčilová, Eva January 2017 (has links)
In this diploma thesis the impacts of both nitrogen fertilization and drought on the content of proteins of the gliadin fraction in case of a winter wheat variety Tiguan were observed. Selected samples were cultivated at two locations in a total duration of two years. Two different conditions were selected: one without the nitrogen fertilization (0 kg N/ ha) and the other with the nitrogen fertilization in 140 kg N/ ha concentration. Second observed factor was the drought which was ensured by roofs above the crops and their cultivation in common climatic environment. Gliadin fraction was separated by the A-PAGE method and the protein quantification carried out by a computer densitometry. Such nitrogen fertilization caused a significant increase of gliadins, especially -1,2 and -5 fractions. Stress induced by the drought caused an increase of gliadin content compared to the control sample, particularly in case of - and - fractions. The most important factor influencing the gliadin content in grains was therefore the nitrogen fertilization in a dry environment. The observed increase of gliadin content was lower in case of the sample which was fertilized in a humid environment than in case of the sample which was fertilized in the dry one.
8

Perfil protéico e uso de marcadores moleculares relacionados à qualidade de panificação em trigo / Protein profile and use of molecular markers related to baking quality of wheat

Dias, Renata de Oliveira 06 July 2010 (has links)
Made available in DSpace on 2015-03-26T13:42:15Z (GMT). No. of bitstreams: 1 texto completo.pdf: 503594 bytes, checksum: 9404a8d4266a856855a02a401fdb8a03 (MD5) Previous issue date: 2010-07-06 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Wheat is one of the principal cereals in the world and is processed into a wide range of products. In recent decades researchers have shown concern over acquisition of cultivars with good baking quality, a characteristic which initially refers to the protein composition of the endosperm, composed principally of the proteins making up gluten. Various methodologies have been employed in the evaluation of this characteristic, including SDS-PAGE (polyacrylamide gel electrophoresis), SE-HPLC (size exclusion high performance liquid chromatography), baking tests and employment of genetic markers. In an attempt to compare the different existing methodologies and propose a strategy for wheat genetic improvement programs based on industrial quality, four different techniques were tests with 45 national cultivars. Six allele-specific markers were used for verification of the presence of the HMW subunits: Glu-D1-1d (5+10) and Glu-B1-2a (7+8), one LMW subunit: Glu-A3d, the presence or absence of 1B/1R translocation: by the presence of Glu-B1 (long arm of the wheat chromosome) or ω- secalin (gene of the short arm of rye) and puroindoline (Pinb-D1b). Also employed where SDS-PAGE, SE-HPLC and baking test methods. As a result of applying the markers, the presence in the genotypes observed was: 71% for subunit Glu-D1-1d (5+10), 16% for Glu-B1-2a (7+8), 60% for Glu-B1 (absence of translocation) and 8% for Pinb-D1b and Glu-A3d. The results of SDS-PAGE suggested a prevalence of the subunits 2* and 1 in chromosome 1A; 7+8, 7+9 and 17+18 in 1B; and 5+10 in 1D. The average values of SE-HPLC were 35.99% and 44.99% for the polymeric protein in protein (PPP) and unextractable polymeric protein (UPP), respectively, and 1.29 for the ratio between gliadins and glutenins (GLI/GLU), with significant variation among the genotypes (p≤0.05). The baking test also showed a significant difference (p≤0.05) between the cultivars under the same conditions. The UPP data were independent of the PPP percentage data, signifying that a portion of the unextractable polymeric protein (UPP) does not depend on the greater percentage of total polymeric proteins. However there was a positive correlation between the score of HMW subunits, evaluated by SDSPAGE, and the UPP values; this indicates that scoring has apparently been efficient in classifying the genotypes of greatest quality. The cultivars without translocation with rye also showed better results for UPP, PPP and GLI/GLU in relation to those possessing translocation. The GLI/LGU ratio is correlated with the specific volume of the bread, but apparently does not guarantee quality of the qualitative characteristics, which may indicate the action of gliadins in extensibility, but with a lack of structure in the gluten network. These results corroborate for the selection of HMW subunits 5+10, cultivars without translocation with rye, with high values of UPP and an appropriate GLI/GLU ratio with the objective of obtaining greater wheat baking quality. / O trigo é um dos principais cereais em todo o mundo, sendo processado para uma gama de produtos. Surgiu nas últimas décadas a preocupação dos pesquisadores com a obtenção de cultivares com boa qualidade de panificação, característica que refere-se primordialmente a constituição protéica do endosperma, composta principalmente pelas proteínas formadoras de glúten. Várias metodologias vêm sendo empregadas na avaliação dessa característica, dentre as quais, estão o SDS-PAGE (eletroforese em gel de poliacrilamida), SE-HPLC (cromatografia líquida de alta eficiência por exclusão molecular), teste de panificação e o emprego de marcadores genéticos. Buscando comparar as diferentes metodologias existentes e propor uma estratégia a programas de melhoramento de trigo voltados à qualidade industrial, testaram-se quatro diferentes técnicas em 45 cultivares nacionais. Usaram-se seis marcadores alelo-específicos direcionados à verificação da presença das subunidades de HMW: Glu-D1-1d (5+10) e Glu-B1-2a (7+8), uma subunidade de LMW: Glu-A3d, a presença ou ausência de translocação 1B/1R: pela presença de Glu-B1 (braço longo do cromossomo de trigo) ou de ω-secalin (gene do braço curto do centeio) e puroindolina (Pinb-D1b). Também foram empregadas as metodologias de SDS-PAGE, SE-HPLC e teste de panificação. Como resultado da aplicação de marcadores obteve-se presença nos genótipos de: 71% para subunidade Glu-D1-1d (5+10), 16% para Glu-B1-2a (7+8), 60% para Glu-B1 (ausência de translocação) e 8% para Pinb-D1b e Glu-A3d. Os resultados de SDS-PAGE apontam uma prevalência das subunidades 2* e 1 no cromossomo 1A; 7+8, 7+9 e 17+18 no 1B; e 5+10 no 1D. Enquanto, os valores médios de SE-HPLC foram de 35,99% e 44,99% para as frações de proteínas poliméricas totais (PPP) e não-extraíveis (UPP), respectivamente, e 1,29 para a relação entre gliadinas e gluteninas (GLI/GLU), com variação significativa entre os genótipos (p≤0,05). O teste de panificação também apontou diferença significativa (p≤0,05) entre as cultivares nas mesmas condições. Os dados de UPP foram independentes dos dados da proporção de PPP, significando que a porção de proteínas poliméricas não-extraíveis (UPP) não depende de maior proporção de proteínas poliméricas totais. Enquanto houve correlação positiva entre o escore dado às subunidades de HMW, avaliadas por SDS-PAGE, e os valores de UPP; isto indica que a pontuação aparentemente vem sendo eficaz em classificar os genótipos de melhor qualidade. As cultivares sem translocação com centeio também obtiveram melhores resultados para UPP, PPP e GLI/GLU em relação as que a possuem. A relação GLI/GLU está correlacionada ao volume específico dos pães, mas aparentemente não garantiu boa qualidade nas características qualitativas, o que pode indicar a ação de gliadinas na extensibilidade, mas com falha na estruturação da rede de glúten. Esses resultados corroboram para uma seleção a favor das subunidades 5+10 de HMW, de cultivares sem translocação com centeio, com alto valor de UPP e razão apropriada de GLI/GLU, quando se objetiva melhorar a qualidade de panificação do trigo.
9

New nanostructured supports with signal amplification features for the detection of molecules and biomolecules of interest

Pla Blasco, Luis 17 May 2021 (has links)
[ES] La presente tesis doctoral titulada "New nanostructured suports with signal amplification features for the detection of molecules and biomolecules of interest" se centra en el diseño y preparación de nuevos materiales híbridos orgánicos-inorgánicos constituidos por puertas moleculares soportadas sobre alúmina mesoporosa con el objetivo de desarrollar nuevos sistemas sensores con aplicaciones potenciales en el campo de la diagnosis y del control alimentario. En el primer capítulo de la tesis se introducen los conceptos en los que están basados los estudios realizados y los materiales preparados. A continuación, en el segundo capítulo se describen los objetivos generales de la tesis que serán abordados en los siguientes apartados. En el tercer capítulo se presenta el diseño y optimización de un nanodispositivo para la detección de la bacteria Mycoplasma fermentans. En primer lugar, los poros de una placa de alúmina mesoporosa se cargan con un indicador fluorescente (rodamina B). Seguidamente, la superficie es funcionalizada con una secuencia de ADN complementaria a una región altamente conservada de la subunidad ribosomal 16S de la bacteria Mycoplasma fermentans. El impedimento estérico generado por las secuencias de ADN ancladas al exterior de los poros impide la salida del indicador encapsulado. Únicamente en presencia de DNA de la bacteria Mycoplasma fermentans, se produce la apertura de los poros permitiéndose la difusión de la carga (rodamina B) que es posteriormente medida mediante espectroscopía de fluorescencia. En el capítulo cuatro se diseña de un nanodispositivo capaz de detectar de forma rápida, sensible y selectiva la bacteria Staphylococcus aureus. Para la preparación del material sensor, un soporte de alúmina mesoporosa es, en primer lugar, cargado con el indicador fluorescente rodamina B. A continuación, los poros del soporte son tapados mediante el anclaje de un aptámero que reconoce de forma específica la bacteria. Solamente en presencia de Staphylococcus aureus se produce la liberación del indicador encapsulado, que es posteriormente medido mediante espectroscopía de fluorescencia. Además, la respuesta obtenida es específica para Staphylococcus aureus. Este sistema ha sido ensayado en muestras reales. En el sexto capítulo, diseña un nanodispositivo híbrido orgánico-inorgánico consistente en un material de alúmina mesoporosa cubierto con una secuencia de ADN específica para la detección de ADN del hongo Pneumocystis jirovecii. En este caso, el soporte de alúmina cargado con rodamina B se recubre con una secuencia de ADN específica para el reconocimiento de este hongo. En presencia del organismo, la horquilla hibrida con el ADN del hongo, lo que resulta en una conformación triplex con elevada afinidad y estabilidad que induce, al mismo tiempo, el desplazamiento de este complejo de la superficie. Como consecuencia de este reconocimiento la carga se libera y es cuantificada mediante espectroscopía de fluorescencia. El sistema ha sido satisfactoriamente validado. En el séptimo capítulo, se diseña un sistema sensor con la capacidad de detectar gluten de forma rápida y sencilla en extractos de alimentos procesados y no procesados. Para ello, un soporte de alúmina mesoporosa se carga con rodamina B y los poros se recubren con un aptámero específicamente diseñado para la detección de la proteína gliadina, que constituye el 50 % del total del clúster de elementos que forman el gluten. La elevada afinidad y especificidad entre el aptámero y la proteína en cuestión hacen que en presencia de ésta se produzca un desplazamiento de la puerta molecular que permite la difusión del colorante encapsulado que es finalmente monitorizado mediante espectroscopía de fluorescencia. Finalmente, en el capítulo octavo se discuten de forma conjunta los resultados obtenidos en los capítulos anteriores y la potencial aplicación de los sistemas desarrollados en el actual sistem / [CA] La present tesi doctoral, titulada "New nanostructured supports with signal amplification features for the detection of molecules and biomolecules of interest", es centra en el disseny i preparació de nous materials híbrids orgànics-inorgànics constituïts per portes moleculars suportades sobre alúmina mesoporosa amb l'objectiu de desenvolupar nous sistemes sensors amb potencials aplicacions en el camp de la diagnosi i del control alimentari. En el primer capítol de la tesi s'introdueixen els conceptes en què estan basats els estudis realitzats i els materials preparats. A continuació, en el segon capítol es descriuen els objectius generals de la tesi que seran abordats en els següents apartats. En el tercer capítol es presenta el disseny i optimització d'un nanodispositiu per a la detecció de la bactèria Mycoplasma fermentans. Primerament, els porus d'una placa d'alúmina mesoporosa són carregats amb un indicador fluorescent (rodamina B). Seguidament, la superfície és funcionalitzada amb una seqüència d'ADN complementaria a una regió altament conservada de la subunitat ribosomal 16S de la bactèria Mycoplasma fermentans. L'impediment estèric generat per les seqüències d'ADN ancorades a l'exterior dels porus impedeix l'alliberament de l'indicador encapsulat. Únicament en presencia d'ADN de la bactèria Mycoplasma fermentans, es produeix l'obertura dels porus permetent la difusió de la càrrega (rodamina B) que és posteriorment mesurada mitjançant fluorescència. En el capítol quatre es dissenya un nanodispositiu capaç de detectar de forma ràpida, sensible i selectiva la bactèria Staphylococcus aureus. Per a la preparació del material sensor, el suport d'alúmina mesoporosa és, primerament, carregat amb l'indicador fluorescent rodamina B. A continuació, els porus del suport són tapats mitjançant l'ancoratge d'un aptàmer que reconeix de forma específica a la bactèria. Solament en presència de Staphylococcus aureus es produeix l'alliberament de l'indicador encapsulat, que és posteriorment mesurat mitjançant espectroscòpia de fluorescència. A més a més, la resposta obtinguda és específica per Staphylococcus aureus. Aquest sistema ha sigut validat amb mostres reals de pacients. En el sisè capítol, es dissenya un nanodispositiu híbrid orgànic-inorgànic consistent en un material d'alúmina mesoporosa cobert amb una seqüència d'ADN específica per a la detecció de l'ADN del fong Pneumocystis jirovecii. En aquest cas, el suport d'alúmina carregat amb l'indicador fluorescent rodamina B és recobert amb una seqüència d'ADN específica per al reconeixement d'aquest fong. En presència de l'organisme, la forquilla hibrida amb l'ADN del fong, resultant en una conformació triplex amb elevada afinitat i estabilitat, que indueix, al mateix temps, el desplaçament d'aquest complex de la superfície. Com a conseqüència d'aquest reconeixement la càrrega és alliberada i quantificada mitjançant espectroscòpia de fluorescència. El sistema ha sigut validat com a mètode diagnòstic mitjançant l'anàlisi de mostres reals de pacients. En el seté capítol, es dissenya un sistema sensor amb la capacitat de detectar gluten de forma ràpida i senzilla en extractes d'aliments processats i no processats. Per a això, un suport d'alúmina mesoporosa es carrega amb indicador fluorescent rodamina B i posteriorment és recobert amb un aptàmer específicament dissenyat per a la detecció de la proteïna gliadina, que constitueix el 50 % del total del clúster d'elements que formen el gluten. L'elevada afinitat i especificitat entre l'aptàmer i la proteïna en qüestió fa que en presència d'aquesta es produesca un desplaçament de la porta molecular que permet la difusió de la càrrega encapsulada i que serà finalment monitoritzada mitjançant espectroscòpia de fluorescència. Finalment, en el capítol vuité es discuteixen de manera conjunta els result / [EN] The PhD thesis hereby presented and entitled "New nanostructured supports with signal amplification features for the detection of molecules and biomolecules of interest", focuses in the design and preparation of new hybrid organic-inorganic materials constituted by molecular gates supported over mesoporous alumina with the aim of developing new sensor probes of potential applications in the fields of diagnosis and food control. In the first chapter, the concepts in which studies and prepared materials are based, are introduced. Next, the second chapter describes the general objectives of this thesis, which will be approached in the following sections. In the third chapter, it is presented in detail the design and optimization process of a nanodevice applied for the detection of Mycoplasma fermentans bacterium. First of all, mesoporous alumina porous films are charged with a fluorescent indicator (rhodamine B). Then, the surface is functionalized with a DNA sequence complementary to a highly conserved region of the 16S ribosomal subunit of the bacterium Mycoplasma fermentans. Steric hindrance generated by DNA sequences on the surface inhibits the release of the encapsulated indicator. Only in the presence of bacterium Mycoplasma fermentans DNA, molecular gates open, allowing payload diffusion to the solution, which is measured by fluorescence spectroscopy. In chapter four, it is carried out the design and optimization of a nanodevice able to detect Staphylococcus aureus bacterium in a fast, sensitive and selective way. For the sensor preparation, alumina mesoporous support is, first, loaded with the rhodamine B fluorescent dye. Then, the mesoporous are blocked through the attachment of an aptamer that recognises specifically this bacterium. Exclusively in the presence of Staphylococcus aureus it is accomplished the release of the encapsulated dye, which is later monitored by fluorescence spectroscopy. The response obtained is specific for Staphylococcus aureus. This system has been validated in real samples. In the sixth chapter, it is detailed the design and optimization process of a hybrid organic-inorganic nanodevice based on a capped mesoporous alumina material for the detection of Pneumocystis jirovecii fungus DNA. In this case, the mesoporous alumina support is loaded with a fluorescent dye and decorated with a specific oligonucleotide sequence designed for the recognition of Pneumocystis fungus. In the presence of the target organism, the fork-like oligonucleotide hybridises with the DNA of the fungus, which results in the adoption of a triplex conformation with high affinity and stability that induces, at the same time, the displacement of this complex from the surface. Consequently, the payload diffused to the solution is quantified through fluorescence spectroscopy. The system has been successfully validated. In the seventh chapter, it was developed a sensor system for gluten detection, in a quick and easy way, in processed and non-processed food extracts. For this, a mesoporous alumina support is loaded with the fluorescent dye rhodamine B, and later was functionalized with an aptamer specifically designed for the detection of gliadin, a protein that constitutes 50 % of average cluster elements that forms gluten. The protein-aptamer high affinity and specificity induce the displacement of the capping aptamer and cargo delivery, which is monitored through fluorescence spectroscopy. Finally, in the eighth chapter, the results obtained in the previous chapters and the potential application of the systems developed as health and food control system are discussed. / We thank the Spanish Government projects MAT2015-64139-C4-1-R, AGL2015-70235-C2-2-R, and TEC2015-71324-R (MINECO/FEDER, UE), the Generalitat Valenciana (project PROMETEOII/2014/047), the Catalan authority (project AGAUR 2014SGR1344), and ICREA under the 2014 ICREA Academia Award for support. This study was supported by the Spanish Government projects RTI2018-100910-B-C41 and SAF2017-82251-R (MCUI/AEI/FEDER, UE), the Generalitat Valenciana (project PROMETEO/2018/024), the Universitat Politècnica de València−Instituto de Investigación Sanitaria La Fe (B02-MIRSA project), CIBER-BBN (NANOPATH and valorization project CANDI-EYE) and co-financed by the EU through the Valencian Community ERDF PO 2014-2020. This research was funded by the Spanish Government, projects RTI2018-100910-B-C41 (MCUI/AEI/FEDER, UE) and CTQ2017-84415-R / Pla Blasco, L. (2021). New nanostructured supports with signal amplification features for the detection of molecules and biomolecules of interest [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/166500

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