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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.
21

N,C-verknüpfte Arylisochinoline: Synthese und Optimierung der biologischen Aktivitäten sowie Strukturaufklärung von Naturstoffen durch HPLC-NMR- und HPLC-MS/MS-Kopplung / N,C-coupled arylisoquinolines: synthesis and optimization of the biological activities and structure elucidation of natural products using HPLC-NMR and HPLC-MS/MS

Albert, Christian Robert January 2012 (has links) (PDF)
Tropische Infektionskrankheiten wie Malaria, Leishmaniose oder auch die Afrikanische Trypanosomiase sind aufgrund von zunehmenden Resistenzen der Erreger, globaler Erwärmung, aber auch von Versäumnissen in der Vergangenheit bei der kontinuierlichen Weiterentwicklung bestehender sowie der Erforschung neuer Medikamente auch im 21. Jahrhundert noch eine große Bedrohung für Millionen von Menschen. Die Suche nach neuartigen Wirkstoffen und deren Weiterentwicklung zu potenziellen Medikamenten ist daher zwingend erforderlich. Insbesondere Produkte des Sekundärstoffwechsels wie etwa die Alkaloide bilden wichtige Grundlagen als Leitstrukturen für pharmazeutische Wirkstoffe. Eine solche Klasse phytochemischen Ursprungs sind die Naphthylisochinolin-Alkaloide mit interessanten strukturellen Eigenschaften sowie pharmakologischen Wirksamkeiten. Einige Vertreter zeigen ausgeprägte In-vitro-Aktivitäten gegen protozoische Erreger wie Plasmodien, Leishmanien und Trypanosomen. Besonders die neuartige Unterklasse ionischer N,C-verknüpfter Naphthylisochinolin-Alkaloide, wie z.B. Ancistrocladinium A und Ancistrocladinium B, zeichnen sich durch gute antileishmaniale Wirkungen aus. In Vorarbeiten zeigten erste Studien zu Struktur-Aktivitäts-Beziehungen (SAR-Studien) mit vereinfachten N,C-gekuppelten Arylisochinolinen, dass sich durch gezielte Strukturvariation die Aktivität gegen einen Erreger verbessern lässt. Zusätzlich wurde mit ersten Untersuchungen zum Wirkmechanismus dieser interessanten Verbindungen begonnen. Darüber hinaus ermöglicht die kontinuierliche Verbesserung der analytischen Methoden inzwischen die schnelle und gezielte Suche nach neuen Verbindungen aus der Natur. Durch die Anwendung von Online-Analyse-Verfahren, wie z.B. die Kopplung von HPLC mit NMR und MS, gelingt die Aufklärung der Konstitution von Substanzen direkt aus Extrakten. Ziel der vorliegenden Arbeit war die Verbesserung der biologischen Aktivitäten der N,C-verknüpften Arylisochinoline durch strukturelle Derivatisierung sowie Beiträge zur Aufklärung des Wirkmechanismus mittels markierter Verbindungen. Zusätzlich sollten Naturstoffe unter Verwendung moderner HPLC-Kopplungstechniken untersucht und strukturell aufgeklärt werden. / Even in the 21st century still tropical infectious diseases like malaria, leishmaniasis or human African trypanosomiasis constitute a big threat for millions of people due to increasing resistances of the pathogens, global warming and failures in the past considering the continuing development of already existing and the research of new drugs. The search for new active agents and their further development to potential drugs is therefore still stringently required. Especially secondary metabolites like the alkaloids present important basics as well as lead structures for pharmaceutical drugs. One class of active plant-derived agents are the naphthylisoquinoline alkaloids bearing interesting structural properties and pharmacological activities. Some representatives show distinct in vitro activities against protozoan pathogens such as plasmodia, leishmania, and trypanosoma. In particular the novel type of ionic N,C-coupled naphthylisoquinoline alkaloids like ancistrocladinium A and ancistrocladinium B exhibit good antileishmanial activities. First structure-activity relationship studies (SAR studies) from previous work with simplified N,C-coupled arylisoquinolines showed that by changing particular structural parameters the activity against a given parasite was improved. Additionally, first investigations on the mode of action of these interesting compounds were started. Furthermore, the continuous improvement of analytical methods enables the fast and directed search for new compounds from natural sources. By the application of online analytical methods, e.g., the hyphenation of HPLC with NMR and MS, it is possible to elucidate the configuration of substances directly from extracts. The aim of the present work was the improvement of the biological activities of N,C-coupled arylisoquinolines by structural derivatization and contributions to the elucidation of the mode of action using labeled compounds. In addition, natural products were to be investigated and structurally elucidated by modern HPLC hyphenation techniques.
22

"Analytik von Metabolisierungsprodukten des Dihydrochalkon-C-Glykosids Aspalathin aus Rooibos (Aspalathus linearis) in vivo"

Kreuz, Susanne January 2009 (has links)
Zugl.: Hannover, Univ., Diss., 2009
23

Analyse des modifications de la cytosine après oxydation de l'ADN par digestion enzymatique et HPLC-MS/MS / Analysis of the modifications of cytosine after oxidation of DNA, by enzymatic digestion and HPLC-MS/MS

Samson-Thibault, François January 2012 (has links)
Résumé: Les dommages à la cytosine, spontanés et induits par des oxydants, sont probablement la principale cause des transitions GC vers AT, la mutation du génome la plus commune chez les organismes aérobiques. Ces dommages sont impliqués dans le processus de mutagenèse, dans le vieillissement et dans le cancer. Les dommages à la cytosine par les oxydants et les radicaux libres sont nombreux et ont été découverts et étudiés dans les monomères de cytosines et dans de courts oligonucléotides. Dans cette étude, nous avons développé une méthode d'analyse par HPLC-MS/MS des plus importants produits d'oxydation de la cytosine dans l'ADN. Cette méthode permet l'analyse de la formation de 5-hydroxy-2'-désoxycytidine (5-OH-dC), de 5,6-dihydroxy-5,6-dihydro-2'-désoxyuridine (dUg), de 1-(2-désoxyribose)-5-hydroxyhydantoïne (HdU) et de 3-(2-désoxyribose)-1-carbamoy1-4,5-dihydroxy-2-oxo-imidazolidine (C422-dC) lors d'irradiation aux rayons gamma par réaction de type fenton et par ozonolyse. Les résultats de l'irradiation de l'ADN aux rayons gamma (en modifications/106bases/Gy) sont de 1.62 pour la 5-OH-dC, de 1.48 pour le dUg, de 7.43 pour la HdU et de 1.38 pour la C422-dC. La réaction de type fenton avec le cuivre donne une formation de dommages environ 25 fois plus grande qu'avec le fer et les deux types (cuivre et fer) donnent des ratios de produits semblables à ceux par les rayons gamma avec une augmentation de la 5- OH-dC et une diminution de la HdU. L'exposition .de l'ADN à l'ozone donne une très grande formation de la HdU et une faible formation des autres produits d'oxydation.//Abstract: The damages to cytosine, spontaneous and inducted by oxidants, are probably the principal cause of the GC to AT transition, the most important mutation of the genome for the aerobic organisms. Those damages are involved in the process of mutagenesis, aging and cancer. The damages to cytosine by oxidants and fre radicals are numerous and have been discovered and studied in monomers of cytosine and in short oligonucleotides. In this study, we have developed a analysis method of the most important oxidation products of cytosine in DNA by HPLC-MS/MS. This method allows the analysis of the formation of 5-hydroxy-2'-deoxycytidine (5-OH-dC), de 5,6-dihydroxy-5,6-dihydro-2'-desxyuridine (dUg), de 1-(2-deoxyribose)-5-hydroxyhydantoin (HdU) et de 3-(2-deoxyribose)- 1-carbamoyl-4,5-dihydroxy-2-oxo-imidazolidine (C422-dC) after irradiation by gamma rays, by fenton type reaction and ozonolysis. The results of the irradiation of DNA by gamma rays (in modifications10[indice supérieur 6] bases/Gy) are of 1.62 for 5-OH-dC, of 1.48 for dUg, of 7.43 for HdU and of 1.38 for C422-dC. The fenton type reaction with copper gives a formation of damages about 25 times higher than with ferrous and both kind gives a ratio of formation similar to the the ones by gamma rays with a increase of 5-OH-dC and a decrease of HdU. The exposition of DNA to ozone gives a strong formation of HdU and a small formation of the other modifications. [symboles non conformes]
24

Identification by HPLC-MS of new detected compounds in sugar beet root exudates for soil P mobilization

Khorassani, Reza January 2008 (has links)
Zugl.: Göttingen, Univ., Diss., 2008
25

Die Aufklärung der Biogenese strukturell ungewöhnlicher Alkaloide aus Triphyophyllum (Dioncophyllaceae) und Antidesma (Euphorbiaceae) und Entwicklung und Einsatz der "Triade" zur phytochemischen Online-Analytik: HPLC-MS-MS, HPLC-NMR und HPLC-CD

Wohlfarth, Michael. January 2002 (has links) (PDF)
Würzburg, Univ., Diss., 2002.
26

Studium antioxidačních látek u hroznových semen

Tomášková, Lenka January 2014 (has links)
It is known, that grape seeds are rich in significant antioxidant. The issue of dealing with the analysis and comparison of antioxidant components in the seeds of Vitis vinifera in the individual varieties has not been sufficiently studied, yet. In the first part of the thesis is an extensive literature focused on a summary of the work, which study substances in the vine seeds and their effect on human health. Experimental work is focused on the study of antioxidant components in the seeds of Vitis vinifera. The experiment was used extracts of the three "normal" (Frankova, Ryzlink vlašský and Cabernet Moravia) and three interspecific varieties (Nativa, Marlen and Kofranka). Spectrometric, using three fundamentally different methods - DPPH, ABTS and FRAP was determined antioxidant activity . Spectrophotometry was further investigated the content of total polyphenolic compounds and total content of flavanols . Technique of high- performance liquid chromatography with mass spectroscopy were analyzed nine major flavonoids (apigenin, astragalin, hyperoside, isorhamnetin, kaempferol, myricetin, quercetin, quercitrin and rutin) and two procyanidins (procyanidin A2 and procyanidin B1). The highest values of antioxidant reached interspecific varieties Marlen and Nativa, at the least antioxidant components were recorded in the variety Cabernet Moravia. However, in complex evaluation, between studied of varieties were not significant differences.
27

Stanovení flavonoidních látek ve vybraných druzích léčivých rostlin používaných v potravinářství

Bačová, Romana January 2015 (has links)
In plant and food research the functional significance of herbs, spices and other plants, including their components is very popular topic. Plant material contains many components that are beneficial to human health by reducing the risk of chronic degenerative diseases. It is necessary to define the individual substances to understand and explain their biological effects. The first part of thesis describes the selected plants (elderberry, nettle, marigold, milk thistle, sea buckthorn, sage, purple coneflower and thyme) and also describes their medicinal properties and uses. The second part of thesis deals with phenolic and flavonoid substances. In the third (experimental) part, of thesis there were qualitatively and quantitatively determined flavonoid compounds in selected plant species. For identification the technique combining liquid chromatography and mass spectrometry - HPLC/MS was used. Extraction was carried out by vortexing and Soxhlet method, using two different concentrations of metanol. These metods were then statistically compared.
28

Avaliação das concentrações plasmáticas e teciduais de vildagliptina em ratos diabéticos e sadios através de microdiálise

Andrade, Cristiane de January 2013 (has links)
Objetivo: Avaliar a farmacocinética da vildagliptina em animais sadios e diabéticos, através da análise dos níveis plasmáticos totais e livres teciduais, empregando-se a técnica de microdiálise. Metodologia: A doença foi induzida nos animais através da administração de 42mg/kg de aloxano através da via intravenosa (i.v.). A vildagliptina foi administrada nas doses de 50 mg/kg (n = 6) e 75 mg/kg (n = 6) via i.v. nos animais diabéticos e na dose de 50 mg/kg (n = 6) nos animais sadios. As concentrações plasmáticas foram quantificadas por CLAE-EM-EM em método desenvolvido e validado. A ligação às proteínas plasmáticas foi determinada por microdiálise, assim como a avaliação tecidual. As sondas de microdiálise foram calibradas in vitro através de diálise e retrodiálise e in vivo utilizando retrodiálise. Para determinação das concentrações teciduais, uma segunda metodologia foi desenvolvida e validada em CLAE-EM-EM. Avaliações compartimentais (software Scientist ®) e não compartimentais (software Excel ®) foram realizadas. Resultados e Discussão: A ligação as proteínas plasmáticas apresentou um valor médio de 9,44 % ± 3,23, condizente com valores encontrados na literatura. Os valores de Ke, clearance, tempo de meia vida, MRT e VDss não apresentaram diferença estatística significativa entre as diferentes doses administradas nos animais diabéticos e entre os animais sadios. As calibrações in vitro por diálise e retrodiálise apresentaram uma recuperação média de 30%, sem diferença estatística entre as duas metodologias empregadas (α = 0,05). A recuperação in vivo também apresentou o mesmo valor médio de recuperação. A penetração tecidual do fármaco em animais diabéticos para as diferentes doses estudadas apresentou mesmo valor nos tecidos estudados, uma média de 0,20. A penetração tecidual semelhante no animal diabético pode ser devido ao dano similar entre os órgãos sofrido durante a indução da doença. Já os animais sadios apresentaram penetração tecidual similar no músculo sem diferença estatística significativa em relação aos diabéticos, entretanto no fígado foi observada uma penetração quarenta e quatro vezes inferior a observada no músculo. Essa disparidade pode ser atribuída a diferença de expressão de proteínas transportadoras no fígado do animal diabetico quando comparado ao sadio. O perfil farmacocinético plasmático foi semelhante entre os dois grupos avaliados, sendo que os parâmetros não diferiram estatisticamente (α = 0,05). Foi empregado o modelo de dois compartimentos para prever as concentrações teciduais. A previsão supõe concentrações superiores as encontradas experimentalmente, contradizendo dados de literatura. Esses dados são inéditos na literatura e demostram a importância da determinação do fármaco em tecidos alvo, uma vez que nem sempre modelos matemáticos conseguem prever a realidade fisiológica. Conclusões: As metodologias analíticas para quantificação da vildagliptina em microdialisado e plasma foram desenvolvidas e validadas, seguindo os requisitos do FDA. O perfil farmacocinético plasmático foi adequadamente descrito pelo modelo de 2 compartimentos. Os perfis teciduais obtidos nesse trabalho podem contribuir para o melhor entendimento dos mecanismos farmacológicos envolvidos e contribuir para futura otimização de terapias. / Objective: To evaluate the pharmacokinetics of vildagliptin in healthy and diabetic animals using a microdialysis technique. Methodology: Diabetes was induced in animals by administration of 42 mg/kg of alloxan intravenously (iv). Vildagliptin was administered intravenously as 50 mg/kg (n = 6) and 75 mg/kg doses (n = 6) in the diabetic animals and as a 50 mg/kg dose (n = 6) in healthy animals. Plasma concentrations were quantified by a HPLC-MS-MS method developed and validated. The plasma protein binding was determined by microdialysis and tissue evaluation. Microdialysis probes were calibrated in vitro using dialysis and retrodialysis and in vivo using retrodialysis. A second method was developed and validated using HPLC-MS-MS to determine tissue concentrations. Results and Discussion: Mean plasma protein was 9.44% ± 3.23, consistent with values reported in the literature. The values of Ke, clearance, half-life, MRT and Vdss showed no statistical difference between the evaluated doses in diabetic animals and between healthy animals (α = 0.05). Calibrations in vitro by dialysis and retrodialysis showed mean recovery of 30%, with no statistical difference between the two methodologies. Mean recovery in vivo also showed the same value. The tissue penetration of the drug in diabetic animals for the different doses studied showed the same value in both tissues studied, an mean of 0.20. The tissue penetration similar in diabetic animals could be due to the similar damage suffered between organs during induction of the disease. The healthy animals showed similar muscle penetration, compared with diabetics animals, although the liver showed a penetration forty four times lower than muscle. This discrepancy can be attributed to differential expression of transporter proteins in the liver of diabetic animals, when compared to the healthy group. The plasma pharmacokinetic profile was similar between the investigated groups, and the parameters did not differ. The two-compartment model was employed to describe the data and used to predict the concentration in the tissues. This is the first study to present these tissue profiles, which presented concentrations below the estimated by the model. These data demonstrate the importance of determining the drug inside the target tissue, as the mathematical models sometimes cannot predict physiology. Conclusions: The analytical methods for the quantification of vildagliptin in microdialysate and plasma were developed and validated by following the requirements of the FDA. The plasma pharmacokinetic profile was correctly described by the model of two compartmental models. The novel tissue profiles obtained in this study may contribute to a better understanding of the pharmacological mechanisms involved and contribute to optimization of future therapies.
29

Avaliação das concentrações plasmáticas e teciduais de vildagliptina em ratos diabéticos e sadios através de microdiálise

Andrade, Cristiane de January 2013 (has links)
Objetivo: Avaliar a farmacocinética da vildagliptina em animais sadios e diabéticos, através da análise dos níveis plasmáticos totais e livres teciduais, empregando-se a técnica de microdiálise. Metodologia: A doença foi induzida nos animais através da administração de 42mg/kg de aloxano através da via intravenosa (i.v.). A vildagliptina foi administrada nas doses de 50 mg/kg (n = 6) e 75 mg/kg (n = 6) via i.v. nos animais diabéticos e na dose de 50 mg/kg (n = 6) nos animais sadios. As concentrações plasmáticas foram quantificadas por CLAE-EM-EM em método desenvolvido e validado. A ligação às proteínas plasmáticas foi determinada por microdiálise, assim como a avaliação tecidual. As sondas de microdiálise foram calibradas in vitro através de diálise e retrodiálise e in vivo utilizando retrodiálise. Para determinação das concentrações teciduais, uma segunda metodologia foi desenvolvida e validada em CLAE-EM-EM. Avaliações compartimentais (software Scientist ®) e não compartimentais (software Excel ®) foram realizadas. Resultados e Discussão: A ligação as proteínas plasmáticas apresentou um valor médio de 9,44 % ± 3,23, condizente com valores encontrados na literatura. Os valores de Ke, clearance, tempo de meia vida, MRT e VDss não apresentaram diferença estatística significativa entre as diferentes doses administradas nos animais diabéticos e entre os animais sadios. As calibrações in vitro por diálise e retrodiálise apresentaram uma recuperação média de 30%, sem diferença estatística entre as duas metodologias empregadas (α = 0,05). A recuperação in vivo também apresentou o mesmo valor médio de recuperação. A penetração tecidual do fármaco em animais diabéticos para as diferentes doses estudadas apresentou mesmo valor nos tecidos estudados, uma média de 0,20. A penetração tecidual semelhante no animal diabético pode ser devido ao dano similar entre os órgãos sofrido durante a indução da doença. Já os animais sadios apresentaram penetração tecidual similar no músculo sem diferença estatística significativa em relação aos diabéticos, entretanto no fígado foi observada uma penetração quarenta e quatro vezes inferior a observada no músculo. Essa disparidade pode ser atribuída a diferença de expressão de proteínas transportadoras no fígado do animal diabetico quando comparado ao sadio. O perfil farmacocinético plasmático foi semelhante entre os dois grupos avaliados, sendo que os parâmetros não diferiram estatisticamente (α = 0,05). Foi empregado o modelo de dois compartimentos para prever as concentrações teciduais. A previsão supõe concentrações superiores as encontradas experimentalmente, contradizendo dados de literatura. Esses dados são inéditos na literatura e demostram a importância da determinação do fármaco em tecidos alvo, uma vez que nem sempre modelos matemáticos conseguem prever a realidade fisiológica. Conclusões: As metodologias analíticas para quantificação da vildagliptina em microdialisado e plasma foram desenvolvidas e validadas, seguindo os requisitos do FDA. O perfil farmacocinético plasmático foi adequadamente descrito pelo modelo de 2 compartimentos. Os perfis teciduais obtidos nesse trabalho podem contribuir para o melhor entendimento dos mecanismos farmacológicos envolvidos e contribuir para futura otimização de terapias. / Objective: To evaluate the pharmacokinetics of vildagliptin in healthy and diabetic animals using a microdialysis technique. Methodology: Diabetes was induced in animals by administration of 42 mg/kg of alloxan intravenously (iv). Vildagliptin was administered intravenously as 50 mg/kg (n = 6) and 75 mg/kg doses (n = 6) in the diabetic animals and as a 50 mg/kg dose (n = 6) in healthy animals. Plasma concentrations were quantified by a HPLC-MS-MS method developed and validated. The plasma protein binding was determined by microdialysis and tissue evaluation. Microdialysis probes were calibrated in vitro using dialysis and retrodialysis and in vivo using retrodialysis. A second method was developed and validated using HPLC-MS-MS to determine tissue concentrations. Results and Discussion: Mean plasma protein was 9.44% ± 3.23, consistent with values reported in the literature. The values of Ke, clearance, half-life, MRT and Vdss showed no statistical difference between the evaluated doses in diabetic animals and between healthy animals (α = 0.05). Calibrations in vitro by dialysis and retrodialysis showed mean recovery of 30%, with no statistical difference between the two methodologies. Mean recovery in vivo also showed the same value. The tissue penetration of the drug in diabetic animals for the different doses studied showed the same value in both tissues studied, an mean of 0.20. The tissue penetration similar in diabetic animals could be due to the similar damage suffered between organs during induction of the disease. The healthy animals showed similar muscle penetration, compared with diabetics animals, although the liver showed a penetration forty four times lower than muscle. This discrepancy can be attributed to differential expression of transporter proteins in the liver of diabetic animals, when compared to the healthy group. The plasma pharmacokinetic profile was similar between the investigated groups, and the parameters did not differ. The two-compartment model was employed to describe the data and used to predict the concentration in the tissues. This is the first study to present these tissue profiles, which presented concentrations below the estimated by the model. These data demonstrate the importance of determining the drug inside the target tissue, as the mathematical models sometimes cannot predict physiology. Conclusions: The analytical methods for the quantification of vildagliptin in microdialysate and plasma were developed and validated by following the requirements of the FDA. The plasma pharmacokinetic profile was correctly described by the model of two compartmental models. The novel tissue profiles obtained in this study may contribute to a better understanding of the pharmacological mechanisms involved and contribute to optimization of future therapies.
30

Evaluation of antioxidant properties and assessment of genetic diversity of Capparis spinosa cultivated in Pantelleria Island

Lo Bosco, Fabrizia 21 April 2017 (has links)
Capparis spinosa is a wild and cultivated bush, which grows mainly in the Mediterranean Basin. Unopened flower buds, called capers are used in the Mediterranean cuisine as flavoring for meat, vegetable and other foods. Several studies evaluated bioactive component and antioxidant activity of Capparis spinosa, increasing the market demand and the economic importance of capers. The aim of this work was to evaluate the contents of bioactive compounds in floral buds fermented in salt of C. spinosa collected from different areas of Pantelleria Island (Italy), testing the effect on healthy function as total antioxidant compounds. Hydrophilic extracts of C. spinosa from Pantelleria Island were characterized by high-performance liquid chromatography-electrospray ionization/mass spectrometry. Among 24 compounds were detected and quantified by HPLC-MS technique: several Kaempherol and Quercetin derivate were characterized, based on UV spectra and MSn fragmentation pattern. The antioxidative activity of caper hydrophilic extracts was assessed in a number of chemical assays (ORAC, DPPH and ABTS). In order to determine the genetic diversity within and among populations of Capparis spinosa from Pantelleria Island, AFLPs (Amplified Fragment Length Polymorphism) markers were employed. Moreover, in the present study, a commercial model of an Electronic Nose (EN), EOS835 (Sacmi), was preliminarily used to investigate the flavor profile of capers. The EN technique was comparated with a classical techniques gas chromatography-mass spectrometry (GC-MS) analysis, using Head Space Solid-Phase Microextraction (HS-SPME) as a solvent-free sample preparation method. / Capparis spinosa es un arbusto silvestre y cultivado, que crece principalmente en la cuenca mediterránea. Cuando los botones de las flores aún no están abiertas reciben el nombre de alcaparras y se utilizan en la alimentación. Varios estudios han demostrado la presencia de un número de componentes bioactivos in C. spinosa y su actividad antioxidante, lo que ha provocado un aumento de su demanda y ha incrementado la importancia económica de las alcaparras. El propósito de este trabajo fue evaluar el contenido de compuestos bioactivos en el capullo de la flor de C. spinosa conservado en salmuera, procedente de diferentes zonas de la isla de Pantelleria (Italia). Los resultados se expresan como actividad antioxidante total. La actividad antioxidante de los extractos hidrófilos de alcaparra se evaluó mediante pruebas químicas (ORAC, DPPH, ABTS). Con el fin de determinar la diversidad genética dentro y entre poblaciones de C. Spinosa, se utilizaron marcadores moleculares del tipo AFLP (Amplified Fragment Length Polymorphism). Los extractos hidrófilos de C. spinosa se caracterizaron mediante cromatografía líquida de alta eficacia - ionización electrospray acoplada a espectrometría de masas. Se han identificado y cuantificado aproximadamente 24 compuestos con la técnica de HPLC-MS, y se han caracterizado varios derivados de kaempferol y quercetina, sobre la base de los espectros UV y con el modelo de fragmentación MSn. En el este estudio también se ha utilizado un modelo de nariz electrónica comercial (ES), EOS835 (Sacmi), para un estudio preliminar del perfil de aroma de las alcaparras. La técnica ES se ha comparado con una técnica de análisis clásicos tales como la cromatografía de gases acoplada a espectrometría de masas (GC-MS), utilizando como método de preparación de la muestra el espacio de cabeza de microextracción en fase sólida (HS-SPME) libre de disolventes. / Capparis spinosa és un arbust silvestre i conreat, que creix principalment a la conca mediterrània. Quan els botons de les flors encara no estan obertes reben el nom de tàperes i s'utilitzen en l'alimentació. Diversos estudis han demostrat la presència d'un nombre de components bioactius in C. spinosa i la seva activitat antioxidant, el que ha provocat un augment de la seva demanda i ha incrementat la importància econòmica de les tàperes. El propòsit d'aquest treball va ser avaluar el contingut de compostos bioactius en el capoll de la flor de C. spinosa conservat en salmorra, procedent de diferents zones de l'illa de Pantelleria (Itàlia). Els resultats s'expressen com a activitat antioxidant total. L'activitat antioxidant dels extractes hidròfils de tàperes es va avaluar mitjançant proves químiques (ORAC, DPPH, ABTS). Per tal de determinar la diversitat genètica dins i entre poblacions de C. Spinosa, es van utilitzar marcadors moleculars del tipus AFLP (Amplified Fragment Length Polymorphism). Els extractes hidròfils de C. spinosa es van caracteritzar mitjançant cromatografia líquida d'alta eficàcia - ionització electrospray acoblada a espectrometria de masses. S'han identificat i quantificat aproximadament 24 compostos amb la tècnica d'HPLC-MS, i s'han caracteritzat diversos derivats de kaempferol i quercetina, sobre la base dels espectres UV i amb el model de fragmentació MSN. Al aquest estudi també s'ha utilitzat un model de nas electrònic comercial (ES), EOS835 (Sacmi), per a un estudi preliminar del perfil d'aroma de les tàperes. La tècnica ÉS s'ha acoblat amb una tècnica d'anàlisi clàssics com ara la cromatografia de gasos acoblada a espectrometria de masses (GC-MS), utilitzant com a mètode de preparació de la mostra l'espai de cap de microextracció en fase sòlida (HS-SPME ) lliure de dissolvents. / Lo Bosco, F. (2017). Evaluation of antioxidant properties and assessment of genetic diversity of Capparis spinosa cultivated in Pantelleria Island [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/79872 / TESIS

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