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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.
61

Antioxidativer und Stoffwechselstatus bei Sauen im peripartalen Zeitraum unter besonderer Berücksichtigung des Mastitis-Metritis-Agalaktie-Komplexes

Derkx, Sina 12 May 2009 (has links)
Der Mastitis-Metritis-Agalaktie-Komplex (MMAK) zählt in der Schweineproduktion zu den wichtigsten Puerperalerkrankungen der Sau. Es existieren verschiedene Prophylaxe- und Therapiekonzepte. Diese können jedoch nicht verhindern, dass es zu wirtschaftlichen Verlusten durch erhöhte Ferkelmortalität und herabgesetzte Fruchtbarkeitsleistung der Sauen kommt. Ziel dieser Untersuchung war es zu ermitteln, wie sich der antioxidative und Stoffwechselstatus von Sauen eines Betriebes mit vermehrtem Auftreten vom MMAK im peripartalen Zeitraum verhält und ob Unterschiede zwischen gesunden und am MMAK erkrankten Sauen bestehen. Des Weiteren wurde geprüft, ob Unterschiede zwischen Jung- und Altsauen existieren und ob er antioxidative Status saisonalen Schwankungen unterliegt. Versuchsanordnung: Im Versuchszeitraum von September 2004 bis Oktober 2005 wurden insgesamt 67 zu Beginn der Untersuchung klinisch gesunden Sauen im peripartalen Zeitraum je vier Blutproben entnommen: (1.) eine Woche vor dem Abferkeln, (2.) 1. Tag nach der Abferkelung, (3.) 8. Tag nach der Abferkelung und (4.) 15. Tag nach der Abferkelung. Die Blutentnahme erfolgte jahreszeitlich gestaffelt. Es wurden die Trolox equivalent antioxidant capacity (TEAC), die Antioxidant capacity of water soluble substances (ACW), die Aktivitäten der Superoxid-Dismutase (SOD), der Glutathion-Peroxidase (GPX), die Selen- und Vitamin E-Konzentration sowie ausgesuchte klinisch-chemische Parameter bestimmt. Parallel dazu wurden Futtermittelproben und eine Brunnenwasserprobe im Labor der Thüringer Landesanstalt für Landwirtschaft untersucht. Die Beurteilung der Sauengesundheit erfolgte nach den Kriterien Fieber, vaginaler Ausfluss, Mastitis und/oder Agalaktie. Es wurde zwischen Jungsau (inklusive 2. Wurf) und Altsau (ab dem 3. Wurf) unterschieden. Ergebnisse: Die TEAC-Konzentration lag bei den am MMAK erkrankten Sauen eine Woche vor dem Abferkeln mit 196 (1. Quartil: 192; 3. Quartil: 224) µmol/l signifikant unter der Konzentration bei den gesunden Sauen mit 246 (192; 275) µmol/l. Bei der folgenden Messung am ersten Tag nach der Abferkelung kam es bei den am MMAK erkrankten Sauen zu einem signifikanten Anstieg der TEAC-Konzentration auf 239 (191; 268) µmol/l. Bei den gesunden Sauen unterlag die TEAC-Konzentration im Untersuchungszeitraum nicht signifikanten Schwankungen. Die ACW-Konzentration lag in fast 70 % der Proben unterhalb der Nachweisgrenze. Die SOD-Aktivität bei den am MMAK erkrankten Sauen lag eine Woche vor dem Abferkeln mit 2725 (2479; 2936) U/g Hb signifikant höher, als die Aktivität bei den gesunden Sauen mit 2366 (2158; 2663) U/g Hb. Bei den gesunden Sauen nahm die Aktivität der SOD bis zum achten Tag nach der Abferkelung signifikant zu und sank am 15. Tag nach der Abferkelung signifikant ab. Bei den am MMAK erkrankten Tieren unterlag die SOD-Aktivität von einer Woche vor dem Abferkeln bis zum achten Tag nach der Abferkelung nicht signifikanten Schwankungen, am 15. Tag nach der Abferkelung sank sie signifikant. Die GPX-Aktivität lag bei den am MMAK erkrankten Sauen eine Woche vor dem Abferkeln mit 267 (207; 298) U/g Hb signifikant niedriger als bei den gesunden Sauen mit 286 (255; 316) U/g Hb. Bei der anschließenden Untersuchung am ersten Tag nach der Abferkelung sank die GPX-Aktivität bei den am MMAK erkrankten Sauen auf 239 (178; 277) U/g Hb signifikant ab, im weiteren Untersuchungsverlauf blieb sie auf einem Niveau. Die Selenkonzentration stieg bei den gesunden und am MMAK erkrankten Sauen während der Untersuchung signifikant an. Die CK- und AST-Aktivitäten stiegen bei den am MMAK erkrankten Sauen am ersten Tag nach der Abferkelung signifikant an und näherten sich bei den folgenden Untersuchungen wieder der Ausgangsaktivität eine Woche vor der Abferkelung an. Der antioxidative Status von gesunden und am MMAK erkrankten Jung- und Altsauen zeigte signifikant höhere Selenkonzentrationen eine Woche vor dem Abferkeln bei den am MMAK erkrankten Altsauen im Vergleich zu den am MMAK erkrankten Jungsauen, sowie eine signifikant höhere TEAC-Konzentration am 15. Tag nach der Abferkelung bei dem am MMAK erkrankten Altsauen im Vergleich zu den an am MMAK erkrankten Jungsauen. Im jahreszeitlichen Vergleich lagen in erster Linie Parameter der September/Oktober Kontrolle signifikant erniedrigt vor. Wobei mit Ausnahme der Selenkonzentration diese signifikanten Unterschiede nicht während des gesamten Probenzeitraumes bestanden. Schlussfolgerungen: In dieser Untersuchung wurden die größten Unterschiede im antioxidativen Abwehrsystem zwischen den gesunden Sauen und am MMAK erkrankten Sauen eine Woche vor dem Abferkeln sowie am ersten Tag nach der Abferkelung festgestellt. Dies lässt vermuten, dass das antioxidative Abwehrsystem der kranken Sauen schon vor der Abferkelung stärkeren Belastungen ausgesetzt war als das der gesunden Sauen. Im Alters- und jahreszeitlichen Vergleich lagen vereinzelt signifikante Unterschiede im antioxidativen Status vor. / The mastitis, metritis, agalactia syndrome (MMAS) counts among the most prominent diseases of sows in pig breeding. Several prophylactic and therapeutic concepts exist but those cannot prevent economical losses due to an increased mortality of piglets and decreased fertility of sows. This examination aims at showing how the sows antioxidant and metabolic status in farms with increased cases of MMAS during the periparturient period behaves and whether differences between young and elder sows exist and whether the antioxidative status is liable to seasonal fluctuations. Test arrangement: During the period from september 2004 to october 2005, four blood samples of 67 peripartal sows which were clinically healthy at the examination’s outset were taken: (1.) one week before littering, (2.) one day after littering, (3.) 8 days after littering and (4.) 15 days after littering. Blood withdrawal occurred seasonally equated. Trolox equivalent antioxidant capacity (TEAC), antioxidant capacity of water-soluble substances (ACW), activity of superoxide dismutase (SOD) glutathione peroxidase (GPX), concentrations of selenium and vitamin E as well as assorted clinical and chemical parameters were analysed. In addition, feeding stuff and water sample were analysed in the laboratories of the Thüringer Landesanstalt für Landwirtschaft. Appraisal of the sows’ health was based on the criteria fever, vaginal discharge, mastitis and/or agalactia. Young sows (including second litter) an elder sows (third litter and up) were distinguished. Results: Concentration of TEAC in sows afflicted with MMAS one week before littering was at 196 (1. quartile: 192; 3. quartile: 224) µmol/l significantly lower than the concentration in healthy sows at 246 (192; 275) µmol/l. The following measurement taken on the first day after littering showed a significant rise to 239 (191; 268) µmol/l in the concentration of TEAC in sows afflicted with MMAS. Healthy sows TEAC concentration showed no significant fluctuations for the duration of the examination. ACW concentration was below detection limit in almost 70 % of the samples. SOD activity one week before littering in sows afflicted with MMAS was significantly higher at 2725 (2479; 2936) U/g Hb than activity in healthy sows at 2366 (2158; 2663) U/g Hb. SOD activity in healthy sows decreased significantly until the 8 day after littering and decreased significantly on day 15 after littering. No significant fluctuations in SOD activity was detected in sows afflicted with MMAS during the period between one week before littering until 8 day after littering, 15 days after littering it decreased significantly. GPX activity was significantly lower in sows afflicted with MMAS than healthy sows one week before littering at 286 (255; 316) U/g Hb. Following examinations one day after littering showed that GPX activity in sows afflicted with MMAS sank significantly to 239 (178; 277) U/g Hb and held that level during the remainder of the examination period. The concentration of selenium rose significantly in healthy and afflicted sows during the examination. CK and AST activities rose significantly in afflicted sows one day after littering and went back to its basic value of one week before littering. The antioxidant status of healthy and afflicted young and elder sows showed significantly higher selenium concentrations a week before littering in elder sows afflicted with MMAS compared to afflicted younger sows, as well as a significantly higher TEAC concentration on day 15 after littering in elder sows afflicted with MMAS compared to younger afflicted sows. During seasonal comparison, parameters of the september/october group were significantly lower, although it must be considered that with exception of selenium concentrations those significant differences were not detected during the entire examination period. Conclusions: The largest differences in the antioxidant defence system between healthy sows and those afflicted with MMAS were detected on e week before and one day after littering. This leads to assumption that the antioxidant defence of afflicted sows was subjected to more stress before littering than that of healthy sows. Sporadic significant differences of the antioxidant status were detected in age and seasonal comparisons.
62

Untersuchungen zum myokardialen Sauerstoffradikal-Stoffwechsel am Tiermodell 30 - 36 Stunden und 6 Wochen nach Myokardinfarkt unter medikamentöser Therapie mittels Ramipril, Metoprolol und Kombinationstherapie Metoprolol/Ramipril

Schulz, Sabine-Susan 12 January 2005 (has links)
An Herzinsuffizienz sind in Deutschland weit mehr als 1 Mio. Menschen erkrankt. Ihre Häufigkeit steigt stetig an. Die Herzinsuffizienz wird als dominierende Herz-Kreislauf-Erkrankung des 21. Jahrhunderts angesehen. Die Hauptursache der Herzinsuffizienz ist die koronare Herzerkrankung besonderes nach stattgehabtem Myokardinfarkt. Sowohl für den akuten Myokardinfarkt als auch für die sich auf dieser Basis entwickelnde Herzinsuffizienz werden Veränderungen im Stoffwechsel der Sauerstoffradikale als pathophysiologisch bedeutsam angesehen. Es wird angenommen, dass als Folge der akuten Myokardischämie oxidativer Stress im Myokard hervorgerufen wird. Dieser kann über die akute Infarktphase hinaus prolongieren. Dadurch werden Mechanismen induziert (Hypertrophie und Apoptose, Störung myokardialer Signaltransduktion), die letztlich zur Herzinsuffizienz führen. Folgerichtig sollten therapeutische Maßnahmen, die zu einer Minimierung von oxidativem Stress führen, protektiv wirken. Im Rahmen dieser Arbeit wurde am Modell des Ligaturinfarktes der Ratte gezeigt, dass es in der Akutphase des Infarktes (30-36 h nach Ligatur) zu gesteigertem oxidativen Stress kommt. Dieser ließ sich anhand gesteigerter myokardialer Konzentration an Lipidperoxiden, die mit einer verminderten Konzentration antioxidativer Enzyme im Herz kombiniert war, dokumentieren. Werden solche Tiere 6 Wochen nach Ligatur untersucht, weisen sie im Herz im Vergleich zu scheinoperierten Tieren eine signifikant erhöhte Konzentration von Lipidperoxiden als Zeichen gesteigerten oxidativen Stresses auf. Parallel dazu werden typische Zeichen einer Herzinsuffizienz (Herzhypertrophie, erhöhter LVEDP, verminderte Kontraktilität) beobachtet. Wurden solche Tiere beginnend nach der akuten Myokardphase mit dem ACE-Hemmer Ramipril und dem Beta-Blocker Metoprolol behandelt - von beiden ist bekannt, dass sie protektiv in den Stoffwechsel der Sauerstoffradikale eingreifen können - wurde ein geringerer myokardialer oxidativer Stress beobachtet, der mit einer verminderten Ausprägung der morphologischen und funktionellen Herzinsuffizienzzeichen einherging. Die kombinierte Gabe von Beta-Blocker und ACE-Hemmer erwies sich dabei sowohl in der Reduktion von oxidativem Stress als auch in ihrem Einfluss auf Herzfunktion und Morphologie den Einzeltherapien überlegen. Als wesentlich für die Reduktion von oxidativem Stress durch Beta-Blockade und ACE-Hemmung wurde die kompensatorische Zunahme des enzymatischen antioxidativen Schutzes im Herz (GSH-Px, SOD) ausgewiesen. / In Germany, more than 1 million people suffer from heart failure and the incidence is continuously growing. Consequently, heart failure is accepted to be the dominant disease of the heart and circulatory system in the 21st century. The main reason for heart failure is coronary heart disease in general, and especially myocardial infarction (MI). Changes in the oxygen radical metabolism are thought to be essential in the pathogenesis of myocardial infarction and heart failure as its important consequence. It is supposed that, as a result of myocardial ischemia, oxidative stress arises in the heart, which can activate and prolong mechanisms (hypertrophy, apoptosis, disturbed signal transduction) well documented to result in heart failure. Consequently, treatment, which reduces the myocardial oxidative stress, should be beneficial. Using the model of ligature infarction in rats, our study shows increased myocardial oxidative stress in the acute phase of MI (30-36 h after ligature) documented by increased concentration of lipid peroxides (LPO) combined with reduced activity of the antioxidative enzymes. When the animals were analyzed 6 weeks after ligature in comparison to sham operated animals, increased oxidative stress and in parallel typical signs for heart failure (myocardial hypertrophy, increased LVEDP, reduced contractility) were observed. Treatment of the animals starting after acute myocardial infarction with the ACE-inhibitor Ramipril and the beta-blocker Metoprolol - both are known to interfere protectively with the oxygen radical metabolism - reduced the myocardial oxidative stress and the morphological and functional signs of failing heart. This effect was most impressive after combined treatment with Metoprolol and Ramipril. The elevated enzymatic antioxidative defense (GSH-Px, SOD) which we found in the heart after beta-blockade and ACE inhibition could be the reason.
63

Thermisch induzierte Veränderungen von Inulin: Strukturelle und funktionelle Konsequenzen

Trabs, Kathrin 14 May 2013 (has links) (PDF)
Die trockene, offene Erhitzung von Inulin im Bereich zwischen 100 und 220 °C resultiert in einem Abbau der Fructanketten. Dabei entsteht in Abhängigkeit vom pH-Wert ein weites Spektrum an Abbauprodukten, primär Mono- und Disaccharide, vorrangig Fructose und verschiedene Di-D-Fructose Dianhydride (DFDA). Da bisher nur ein DFDA als kommerzieller Standard erhältlich ist, wurden aus einem Inulinkaramell nach Aufreinigung per Flash-Chromatographie und semipräparativer HPLC-RI vier DFDA isoliert und identifiziert. Dabei handelt es sich um α-D-Fruf-1,2´:2,3´-β-D-Fruf (DFA III), α-D-Fruf-1,2´:2,1´-α-D-Fruf (DFA VII), β-D-Fruf-1,2´:2,1´-β-D-Fruf und α-D-Fruf-1,2´:2,1´-β-D-Fruf (DFA I). Eine fünfte Verbindung wurde als α-D-Fruf-1,2´-β-D-Fruf identifiziert, welches vermutlich aus α-D-Fruf-1,2´:2,6´-β-D-Fruf (DFA V) freigesetzt wird. Während unter sauren Bedingungen vor allem Fructose bestimmt wurde, kommt es unter basischen Erhitzungsbedingungen verstärkt zur Bildung löslicher, farbiger Verbindungen. Durch einen basischen Zusatz kann außerdem die antioxidative Wirksamkeit der Inulinkaramelle gesteigert werden, wobei wahrscheinlich besonders die farbigen Verbindungen für die antioxidative Wirkung verantwortlich sind. Die präbiotische Wirkung kann durch die Erhitzung nicht gesteigert werden, wird jedoch bei moderaten Erhitzungsbedinungen (etwa 160 °C) nicht verrringert. Durch eine gezielte Erhitzung kann Inulin so verändert werden, dass sich neue Eigenschaften und damit auch neue Einsatzmöglichkeiten in der Lebensmittelindustrie ergeben.
64

Efeitos do peróxido de hidrogênio sobre a germinação e na aclimatação de plantas de milho à salinidade / Hydrogen peroxide effects on the germination and the acclimation of maize plants subjected to salinity

Gondim, Franklin Aragão January 2008 (has links)
GONDIM, Franklin Aragão. Efeitos do peróxido de hidrogênio sobre a germinação e na aclimatação de plantas de milho à salinidade, Fortaleza - CE, 2008. 116 f. Dissertação (Mestrado em Bioquímica) - Centro de Ciências, Universidade Federal do Ceará, Fortaleza, 2008. / Submitted by Eric Santiago (erichhcl@gmail.com) on 2016-05-20T12:26:03Z No. of bitstreams: 1 2008_dis_fagondim.pdf: 2614140 bytes, checksum: 6acc0bd93625516278dbfcd0d8714f5d (MD5) / Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-05-20T12:38:05Z (GMT) No. of bitstreams: 1 2008_dis_fagondim.pdf: 2614140 bytes, checksum: 6acc0bd93625516278dbfcd0d8714f5d (MD5) / Made available in DSpace on 2016-05-20T12:38:05Z (GMT). No. of bitstreams: 1 2008_dis_fagondim.pdf: 2614140 bytes, checksum: 6acc0bd93625516278dbfcd0d8714f5d (MD5) Previous issue date: 2008 / The aim of this work was to evaluate the effects of the hydrogen peroxide (H2O2) on germination and acclimation of maize plants subject to the saline stress, in order to better understand the physiological and biochemical mechanisms involved. In the three experiments the triple hybrid of maize (Zea mays L) BRS 3003 was used. In the first experiment, the effects of H2O2 on germination of the maize seeds were evaluated; in the second, the effects of pre-treating by soaking maize seeds in H2O2 solution on the activities of antioxidative enzymes and isoenzymes; and as, the effects of the pre-treatment of maize seeds with H2O2 on acclimation of the plants to salinity and the possible mechanisms involved with this process. In the first experiment, which was carried out in a growth room, H2O2 accelerated the germination rate of maize seeds at 100 mM, but, not at 500 mM. In the second experiment, also carried out in growth room, it was observed that the pre-treatment of the seeds induced a pronounced increase in the activities of the enzymes ascorbate peroxidase (APX) and catalase (CAT), after 30 h of soaking in H2O2. It was also observed that the activity of the Guaiacol peroxidase (GPX) was smaller in the seeds soaked in H2O2 for 12, 24, 30, 36 and 42 h, in relation to those soaked in distilled water (control). However, H2O2 treatment for 48 h showed no significant differences as compared with control. The superoxide dismutase (SOD) activity was not affected by the pre-treatment of the seeds, except for the 24 h treatment. In the seeds, it was detected only one isoform of CAT and six of SOD. The pre-treatment of the seeds did not cause great changes in those isoforms, except for the intensity of the band of activity of CAT visualized in the polyacrylamide gel, which was very superior to that of the control, when the seeds were soaked by 36 and 48 h with H2O2. The increases in the activities of APX and, especially, of CAT, could be associated with the acceleration of the germination process. In the third experiment, which was carried out initially at growth room and, later, at the glasshouse, maize seeds were pre-treated for 36 h by soaking in solution of H2O2 100 mM or in distilled water. Those seeds were germinated on filter paper moistened with nutrient solution in the presence or absence of NaCl 80 mM, in a growth room. After six days, the seedling were transferred to the glasshouse and cultivated in trays containing only nutrient solution (control treatment) or nutrient solution with NaCl at 80 mM. Plants were harvest with 6, 11 and 16 days old. The results showed the pre-treatment of the seeds with H2O2 induced acclimation of the plants to the salinity. It decreased the deleterious effects of salt stress on the growth (biomass production and leaf area) of maize. This fact was associated with a higher efficiency of the antioxidative system of plants pre-treated with H2O2. CAT was the most important among the H2O2 scavenging enzymes in leaves, but, its activity was strongly reduced by salinity in plants 6 and 11 days old, however, this effect was totally reverted in the stressed plants originated from seeds pre-treated with H2O2. On the other hand, in the roots of plants submitted to saline stress, the activity of SOD was stimulated by the pre-treatment of the seeds with H2O2, in the three periods of harvest. In general, salinity reduced the photosynthetic parameters (stomatal conductance, net CO2 assimilation rate, transpiration and intracellular CO2 concentration) and the H2O2 pre-treatment of seeds was not capable to revert that effect. In terms of osmotic adjustment, the contents of organic solutes were not positively correlated to the process of acclimation to salt stress of the plants pre-treated with H2O2 to the salinity. However, the smallest values of the Na+/K+ ratio in roots and in leaves were found for the pre-treated plants submitted to salinity, when compared to those originated from of seeds pre-treated with water (control) and submitted to that same treatment, and it may also be a responsible factor for the acclimation of the maize plants to the salinity. / Este trabalho teve como objetivo avaliar os efeitos do peróxido de hidrogênio (H2O2) sobre a germinação e a aclimatação de plantas de milho ao estresse salino, estudando os mecanismos fisiológicos e bioquímicos envolvidos. Nos experimentos, em número de três, foi utilizado o híbrido triplo de milho (Zea mays L), o BRS 3003. No primeiro experimento, foram avaliados os efeitos do H2O2 na germinação das sementes de milho; no segundo, foram avaliados os efeitos do pré-tratamento de embebição das sementes de milho com H2O2 nas atividades das enzimas e isoenzimas antioxidativas e, no terceiro, foram avaliados os efeitos do pré-tratamento de sementes de milho com H2O2 sobre a aclimatação das plantas de milho à salinidade e os mecanismos possivelmente envolvidos. No primeiro experimento, o qual foi realizado em sala da germinação, observou-se que o H2O2 na concentração de 100 mM acelerou o processo de germinação das sementes de milho, o mesmo não ocorrendo na concentração de 500 mM. No segundo experimento, o qual também foi realizado em sala de germinação, observou-se que o pré-tratamento das sementes induziu forte aumento nas atividades das enzimas peroxidase do ascorbato (APX) e catalase (CAT), desde o tempo de embebição de 30 h das sementes com H2O2. Já com relação à peroxidase do guaiacol (GPX), observou-se que a atividade dessa enzima foi menor nas sementes embebidas com H2O2 nos tempos de 12, 24, 30, 36 e 42 h, em relação àquelas embebidas em água destilada (controle), porém, nas pré-tratadas por um tempo de 48 h não foram observadas diferenças significativas entre os tratamentos. A dismutase do superóxido (SOD), por sua vez, não foi afetada pelo pré-tratamento das sementes, exceto no tratamento de embebição das sementes com H2O2 por 24 h. Nas sementes, foi detectada apenas uma isoenzima de CAT e seis de SOD. O pré-tratamento das sementes não provocou alterações nessas isoformas, exceto com relação à intensidade da banda de atividade da CAT visualizada no gel de poliacrilamida, que se mostrou muito superior àquela do controle, quando as sementes foram embebidas por 36 e 48 h com H2O2. É possível que os aumentos nas atividades da APX e, especialmente, da CAT, tenham sido responsáveis pela aceleração do processo de germinação. No terceiro experimento, o qual foi conduzido inicialmente em Sala de germinação e, em seguida, em casa de vegetação, foram utilizadas sementes de milho prétratadas por 36 h de embebição em solução de H2O2 a 100 mM ou em água destilada. Essas sementes foram postas para germinar em folhas de papel de filtro umedecidas com solução nutritiva em presença ou ausência de NaCl a 80 mM em sala de germinação. Decorridos seis dias, as plântulas foram transferidas para a casa de vegetação e cultivadas hidroponicamente em presença ou ausência de NaCl a 80 mM, sendo feitas coletas das plantas aos 6, 11 e 16 dias de idade. Como resultado, observou-se que o pré-tratamento das sementes com H2O2 induziu a aclimatação das plantas à salinidade, reduzindo parcialmente os efeitos deletérios da salinidade na produção de matéria e na área foliar. Esse resultado pode ser atribuído, pelo menos em parte, a uma maior eficiência do sistema antioxidativo das plantas oriundas de sementes pré-tratadas com H2O2. A CAT, que se mostrou a principal enzima eliminadora de H2O2, teve sua atividade nas folhas fortemente reduzida pela salinidade, nas plantas com seis dias de idade, sendo este efeito totalmente revertido nas plantas provenientes de sementes pré-tratadas com H2O2. Por outro lado, nas raízes das plantas submetidas ao estresse salino, a atividade da SOD foi estimulada pelo pré-tratamento das sementes com H2O2, nos três tempos de coleta. De modo geral, a salinidade reduziu os parâmetros fotossintéticos (condutância estomática, transpiração, fotossíntese e concentração interna de CO2) e o pré-tratamento das sementes não foi capaz de reverter esse efeito. Não foi possível estabelecer-se uma correlação precisa entre os teores de solutos orgânicos e o processo de aclimatação das plantas pré-tratadas com H2O2 à salinidade, em termos de ajustamento osmótico. No entanto, os menores valores da razão Na+/K+ nas raízes e, especialmente, nas folhas das plantas pré-tratadas e submetidas à salinidade, em relação àquelas oriundas de sementes pré-tratadas com água (controle) e submetidas a esse mesmo tratamento, aos 16 dias de idade, pode também ter sido um fator responsável, pelo menos em parte, pela aclimatação das plantas de milho à salinidade.
65

PrÃ-tratamento foliar com H2O2 como estratÃgia para minimizar os efeitos deletÃrios da salinidade em plantas de milho / H2O2 leaf spray pretreatment alleviates the deleterious effects of salinity on maize plants

Franklin AragÃo Gondim 19 September 2012 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Este trabalho teve como objetivo avaliar os efeitos do prÃ-tratamento de pulverizaÃÃo foliar das plantas de milho com perÃxido de hidrogÃnio (H2O2) sobre a aclimataÃÃo ao estresse salino, estudando os mecanismos fisiolÃgicos e bioquÃmicos envolvidos. A presente tese foi dividida em trÃs experimentos independentes que resultaram na produÃÃo de trÃs capÃtulos, cada um correspondendo a um artigo cientÃfico. Os experimentos foram conduzidos em casa de vegetaÃÃo, sob condiÃÃes hidropÃnicas, utilizando o hÃbrido triplo de milho (Zea mays L), BRS 3003. Oito dias apÃs a semeadura, as plÃntulas foram pulverizadas com Ãgua destilada (controle) ou soluÃÃo aquosa de H2O2 na concentraÃÃo de 10 mM e, 48 h apÃs o inÃcio da pulverizaÃÃo, foram submetidas ao tratamento com NaCl a 80 mM. No primeiro trabalho, foram estudados os efeitos da aplicaÃÃo foliar de H2O2 no crescimento e nos teores de solutos orgÃnicos e inorgÃnicos de plantas de milho crescendo sob condiÃÃes salinas. Verificou-se que o prÃ-tratamento de pulverizaÃÃo das plantas de milho com H2O2 induziu aclimataÃÃo das plantas de milho ao estresse salino, revertendo parcialmente os efeitos deletÃrios da salinidade no crescimento. Este efeito foi atribuÃdo, pelo menos em parte, a um maior acÃmulo de proteÃnas solÃveis, carboidratos solÃveis e NO3-, bem como a um menor acÃmulo de Ãons tÃxicos (Na+ e Cl-) nas folhas. O segundo trabalho avaliou os efeitos da aplicaÃÃo foliar de H2O2 no crescimento, na atividade das enzimas antioxidativas, na peroxidaÃÃo dos lipÃdios (teores de malondialdeÃdo-MDA) e na expressÃo da enzima catalase (CAT) em plantas de milho sob condiÃÃes de estresse salino. Constatou-se que a salinidade reduziu o crescimento das plantas e que a aplicaÃÃo foliar de H2O2 minimizou este efeito. Observou-se tambÃm que as enzimas antioxidativas estudadas (catalase, peroxidase do guaiacol, perdoxidase do ascorbato e dismutase do superÃxido) tiveram suas atividades aumentadas pela aplicaÃÃo foliar de H2O2. A CAT se mostrou a principal enzima responsiva ao H2O2 e seu aumento de atividade parace estar relacionado à regulaÃÃo da expressÃo gÃnica. Sob condiÃÃes salinas, a menor peroxidaÃÃo de lipÃdios foi encontrada nas plantas que apresentaram maiores atividades da CAT. De modo geral, concluiu-se que a pulverizaÃÃo foliar das plantas de milho com H2O2 foi capaz de reduzir os efeitos deletÃrios da salinidade no crescimento das plantas e na peroxidaÃÃo dos lipÃdios. Essas respostas podem ser atribuÃdas, pelo menos em parte, à capacidade do H2O2 de induzir aumento na atividade e/ou expressÃo das enzimas antioxidativas, especialmente a CAT. O terceiro trabalho analisou os efeitos da aplicaÃÃo foliar de H2O2 na Ãrea foliar, nos teores relativos de clorofila, nos teores relativos de Ãgua, nas trocas gasosas e nos teores de H2O2, ascorbato e glutationa de plantas de milho crescendo sob condiÃÃes salinas. De modo geral, a salinidade reduziu a Ãrea foliar, os teores relativos de clorofila e os teores relativos de Ãgua e a pulverizaÃÃo foliar com H2O2 foi eficaz em minimizar esse efeito. A salinidade reduziu os parÃmetros fotossintÃticos (condutÃncia estomÃtica, transpiraÃÃo, fotossÃntese e concentraÃÃo interna de CO2) e o prÃ-tratamento de pulverizaÃÃo das plantas com H2O2 foi capaz de reverter parcialmente esse efeito. Os teores de H2O2 foram aumentados pela salinidade tanto nas folhas como nas raÃzes e a pulverizaÃÃo foliar com H2O2 mostrou-se eficiente em reduzir este efeito, sem, contudo, alterar o estado redox dos antioxidantes analisados (ascorbato e glutationa). / This study evaluated the effects of H2O2 leaf spraying pretreatment on the maize plant acclimation to salt stress, studying the physiological and biochemical mechanisms involved. The present thesis was divided into three independent experiments that resulted in three chapters, each one corresponding to a scientific article. The experiments were conducted under hydroponic conditions and maintained in greenhouse, the plant model used was triple hybrid of maize (Zea mays L.), BRS 3003. Eight days after sowing (DAS), the seedlings were sprayed with 10 mM H2O2 solution or distilled water (as a control). Forty-eight hours after the spraying beginning, the seedlings were subjected to treatment with NaCl at 80 mM. In the first study, we analyzed the effects of H2O2 leaf spraying pretreatment on the growth and on the levels of organic and inorganic solutes in maize plants under salt stress. It was observed that H2O2 leaf spraying pretreatment promoted plant acclimation to salt stress, reducing the deleterious effects of salinity on the maize growth. This effect can be attributed, at least partially, to a great production of proteins, and soluble carbohydrates and NO3- as well as lower levels of Cl- and Na+ in leaves. The second study evaluated the effects of H2O2 leaf spraying pretreatment on growth, antioxidative enzymes activity, lipid peroxidation (levels of malondialdehyde - MDA) and on the catalase expression (CAT) in maize plants under salt stress. It was observed that salinity reduced maize seedling growth when compared to control conditions, and H2O2 foliar spraying was effective in minimizing this effect. Analysis of the antioxidative enzymes (catalase, guaiacol peroxidase, ascorbate peroxidase and superoxide dismutase) revealed that H2O2 leaf spraying increased antioxidant enzyme activities. CAT was the most responsive of these enzymes to H2O2, with higher activity since the beginning of the treatment (48 h), while guaiacol peroxidase and ascorbate peroxidase were responsive only at later stages (240 h) of treatment. Increased CAT activity appears linked to gene expression regulation. Lower MDA levels were detected in plants with higher CAT activity, which may result from the protective function of this enzyme. Overall, we can conclude that pretreatment with H2O2 leaf spraying was able to reduce the deleterious salinity effects on seedling growth and lipid peroxidation. These responses could be attributed to the H2O2 ability to induce antioxidant defenses, especially CAT activity. The third study evaluated the effects of H2O2 leaf spraying pretreatment on leaf area, relative chlorophyll content, relative water content, gas exchange and on the H2O2, ascorbate and glutathione contents in salt-stressed maize plants. In general, the salinity reduced leaf area, relative chlorophyll content and relative water content of the maize plants in comparison to the plants that grew under control conditions, moreover H2O2 leaf spraying was effective in minimize this effect. The salt treatment reduced photosynthetic parameters and, the H2O2 leaf spray was able to partially reverse this effect. The H2O2 content was increased by salinity in both, leaves and roots, and H2O2 leaf spray was effective in reducing this negative effect. The H2O2 foliar application did not alter the redox state of the antioxidants studied (ascorbate and glutathione).
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Efeitos do perÃxido de hidrogÃnio sobre a germinaÃÃo e na aclimataÃÃo de plantas de milho à salinidade / Hydrogen peroxide effects on the germination and the acclimation of maize plants subjected to salinity

Franklin AragÃo Gondim 03 March 2008 (has links)
AssociaÃÃo TÃcnico-CientÃfica Eng. Paulo de Frontin / nÃo hà / Este trabalho teve como objetivo avaliar os efeitos do perÃxido de hidrogÃnio (H2O2) sobre a germinaÃÃo e a aclimataÃÃo de plantas de milho ao estresse salino, estudando os mecanismos fisiolÃgicos e bioquÃmicos envolvidos. Nos experimentos, em nÃmero de trÃs, foi utilizado o hÃbrido triplo de milho (Zea mays L), o BRS 3003. No primeiro experimento, foram avaliados os efeitos do H2O2 na germinaÃÃo das sementes de milho; no segundo, foram avaliados os efeitos do prÃ-tratamento de embebiÃÃo das sementes de milho com H2O2 nas atividades das enzimas e isoenzimas antioxidativas e, no terceiro, foram avaliados os efeitos do prÃ-tratamento de sementes de milho com H2O2 sobre a aclimataÃÃo das plantas de milho à salinidade e os mecanismos possivelmente envolvidos. No primeiro experimento, o qual foi realizado em sala da germinaÃÃo, observou-se que o H2O2 na concentraÃÃo de 100 mM acelerou o processo de germinaÃÃo das sementes de milho, o mesmo nÃo ocorrendo na concentraÃÃo de 500 mM. No segundo experimento, o qual tambÃm foi realizado em sala de germinaÃÃo, observou-se que o prÃ-tratamento das sementes induziu forte aumento nas atividades das enzimas peroxidase do ascorbato (APX) e catalase (CAT), desde o tempo de embebiÃÃo de 30 h das sementes com H2O2. Jà com relaÃÃo à peroxidase do guaiacol (GPX), observou-se que a atividade dessa enzima foi menor nas sementes embebidas com H2O2 nos tempos de 12, 24, 30, 36 e 42 h, em relaÃÃo Ãquelas embebidas em Ãgua destilada (controle), porÃm, nas prÃ-tratadas por um tempo de 48 h nÃo foram observadas diferenÃas significativas entre os tratamentos. A dismutase do superÃxido (SOD), por sua vez, nÃo foi afetada pelo prÃ-tratamento das sementes, exceto no tratamento de embebiÃÃo das sementes com H2O2 por 24 h. Nas sementes, foi detectada apenas uma isoenzima de CAT e seis de SOD. O prÃ-tratamento das sementes nÃo provocou alteraÃÃes nessas isoformas, exceto com relaÃÃo à intensidade da banda de atividade da CAT visualizada no gel de poliacrilamida, que se mostrou muito superior Ãquela do controle, quando as sementes foram embebidas por 36 e 48 h com H2O2. à possÃvel que os aumentos nas atividades da APX e, especialmente, da CAT, tenham sido responsÃveis pela aceleraÃÃo do processo de germinaÃÃo. No terceiro experimento, o qual foi conduzido inicialmente em Sala de germinaÃÃo e, em seguida, em casa de vegetaÃÃo, foram utilizadas sementes de milho prÃtratadas por 36 h de embebiÃÃo em soluÃÃo de H2O2 a 100 mM ou em Ãgua destilada. Essas sementes foram postas para germinar em folhas de papel de filtro umedecidas com soluÃÃo nutritiva em presenÃa ou ausÃncia de NaCl a 80 mM em sala de germinaÃÃo. Decorridos seis dias, as plÃntulas foram transferidas para a casa de vegetaÃÃo e cultivadas hidroponicamente em presenÃa ou ausÃncia de NaCl a 80 mM, sendo feitas coletas das plantas aos 6, 11 e 16 dias de idade. Como resultado, observou-se que o prÃ-tratamento das sementes com H2O2 induziu a aclimataÃÃo das plantas à salinidade, reduzindo parcialmente os efeitos deletÃrios da salinidade na produÃÃo de matÃria e na Ãrea foliar. Esse resultado pode ser atribuÃdo, pelo menos em parte, a uma maior eficiÃncia do sistema antioxidativo das plantas oriundas de sementes prÃ-tratadas com H2O2. A CAT, que se mostrou a principal enzima eliminadora de H2O2, teve sua atividade nas folhas fortemente reduzida pela salinidade, nas plantas com seis dias de idade, sendo este efeito totalmente revertido nas plantas provenientes de sementes prÃ-tratadas com H2O2. Por outro lado, nas raÃzes das plantas submetidas ao estresse salino, a atividade da SOD foi estimulada pelo prÃ-tratamento das sementes com H2O2, nos trÃs tempos de coleta. De modo geral, a salinidade reduziu os parÃmetros fotossintÃticos (condutÃncia estomÃtica, transpiraÃÃo, fotossÃntese e concentraÃÃo interna de CO2) e o prÃ-tratamento das sementes nÃo foi capaz de reverter esse efeito. NÃo foi possÃvel estabelecer-se uma correlaÃÃo precisa entre os teores de solutos orgÃnicos e o processo de aclimataÃÃo das plantas prÃ-tratadas com H2O2 à salinidade, em termos de ajustamento osmÃtico. No entanto, os menores valores da razÃo Na+/K+ nas raÃzes e, especialmente, nas folhas das plantas prÃ-tratadas e submetidas à salinidade, em relaÃÃo Ãquelas oriundas de sementes prÃ-tratadas com Ãgua (controle) e submetidas a esse mesmo tratamento, aos 16 dias de idade, pode tambÃm ter sido um fator responsÃvel, pelo menos em parte, pela aclimataÃÃo das plantas de milho à salinidade. / The aim of this work was to evaluate the effects of the hydrogen peroxide (H2O2) on germination and acclimation of maize plants subject to the saline stress, in order to better understand the physiological and biochemical mechanisms involved. In the three experiments the triple hybrid of maize (Zea mays L) BRS 3003 was used. In the first experiment, the effects of H2O2 on germination of the maize seeds were evaluated; in the second, the effects of pre-treating by soaking maize seeds in H2O2 solution on the activities of antioxidative enzymes and isoenzymes; and as, the effects of the pre-treatment of maize seeds with H2O2 on acclimation of the plants to salinity and the possible mechanisms involved with this process. In the first experiment, which was carried out in a growth room, H2O2 accelerated the germination rate of maize seeds at 100 mM, but, not at 500 mM. In the second experiment, also carried out in growth room, it was observed that the pre-treatment of the seeds induced a pronounced increase in the activities of the enzymes ascorbate peroxidase (APX) and catalase (CAT), after 30 h of soaking in H2O2. It was also observed that the activity of the Guaiacol peroxidase (GPX) was smaller in the seeds soaked in H2O2 for 12, 24, 30, 36 and 42 h, in relation to those soaked in distilled water (control). However, H2O2 treatment for 48 h showed no significant differences as compared with control. The superoxide dismutase (SOD) activity was not affected by the pre-treatment of the seeds, except for the 24 h treatment. In the seeds, it was detected only one isoform of CAT and six of SOD. The pre-treatment of the seeds did not cause great changes in those isoforms, except for the intensity of the band of activity of CAT visualized in the polyacrylamide gel, which was very superior to that of the control, when the seeds were soaked by 36 and 48 h with H2O2. The increases in the activities of APX and, especially, of CAT, could be associated with the acceleration of the germination process. In the third experiment, which was carried out initially at growth room and, later, at the glasshouse, maize seeds were pre-treated for 36 h by soaking in solution of H2O2 100 mM or in distilled water. Those seeds were germinated on filter paper moistened with nutrient solution in the presence or absence of NaCl 80 mM, in a growth room. After six days, the seedling were transferred to the glasshouse and cultivated in trays containing only nutrient solution (control treatment) or nutrient solution with NaCl at 80 mM. Plants were harvest with 6, 11 and 16 days old. The results showed the pre-treatment of the seeds with H2O2 induced acclimation of the plants to the salinity. It decreased the deleterious effects of salt stress on the growth (biomass production and leaf area) of maize. This fact was associated with a higher efficiency of the antioxidative system of plants pre-treated with H2O2. CAT was the most important among the H2O2 scavenging enzymes in leaves, but, its activity was strongly reduced by salinity in plants 6 and 11 days old, however, this effect was totally reverted in the stressed plants originated from seeds pre-treated with H2O2. On the other hand, in the roots of plants submitted to saline stress, the activity of SOD was stimulated by the pre-treatment of the seeds with H2O2, in the three periods of harvest. In general, salinity reduced the photosynthetic parameters (stomatal conductance, net CO2 assimilation rate, transpiration and intracellular CO2 concentration) and the H2O2 pre-treatment of seeds was not capable to revert that effect. In terms of osmotic adjustment, the contents of organic solutes were not positively correlated to the process of acclimation to salt stress of the plants pre-treated with H2O2 to the salinity. However, the smallest values of the Na+/K+ ratio in roots and in leaves were found for the pre-treated plants submitted to salinity, when compared to those originated from of seeds pre-treated with water (control) and submitted to that same treatment, and it may also be a responsible factor for the acclimation of the maize plants to the salinity.
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Vliv působení uranu na metabolismus sacharidů kultivovaných rostlin. / The effect of uranium on carbohydrate metabolism of cultivated plants.

Lábusová, Jana January 2013 (has links)
Nowadays, the environmental pollution by heavy metals is very serious problem all around the world. Radionuclides, including uranium, are heavy metals that cause both chemical and radioactive pollution. Naturally occurring uranium is not so dangerous for living organisms. Human activities, especially uranium ore mining and use of phosphate fertilizers, have increased its concentration in the environment with consequent contamination of soil, water and air. Compared to other countries, the Czech Republic is relatively rich in deposits of uranium ore. Extensive mining results in large contaminated areas, containing not only uranium but also other heavy metals and xenobiotics that need to be removed from the environment. One way how to decontaminate soils and waters is phytoremediation. This eco-friendly and cost-effective technique exploits the ability of plants to take up, translocate, transform and sequester xenobiotics. In order to provide functional phytoremediation, it is necessary to understand the mechanisms of plant responses to stress caused by xenobiotics. Therefore in my master thesis, I focused on the impact of uranium on physiological processes of uranium-stressed plants, with the emphasis on carbohydrate metabolism and antioxidative defense mechanism. Powered by TCPDF (www.tcpdf.org)
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Vliv chronické hypoxie na antioxidační kapacitu myokardu potkana. / Effect of chronic hypoxia on antioxidative capacity of rat myocardium.

Závišková, Kristýna January 2014 (has links)
Adaptation to chronic hypoxia activates endogenous signaling cascades, which lead to cardiac protection against acute ischemia/reperfusion (I/R) injury. The molecular mechanism of this phenomenon has not been fully clarified yet. However, it was proved that reactive oxygen species (ROS) take part in cardioprotective signaling pathway inducted by chronic hypoxia. The high level of ROS must be precisely regulated by antioxidative system of a cell. The aim of diploma thesis was to examine the effect of intermittent hypobaric hypoxia (IHH, 7 000 m) on relative amount of antioxidative enzymes (peroxiredoxin 6 - PRX6, thioredoxin 1 and 2 - TRX1 and TRX2, thioredoxin reductase 1 - TRXR1) and also enzymes of iron metabolism (heme oxygenase 1 and 2 - HO1 and HO2, aconitase 1 and 2 - ACO1 and ACO2), which participate in regulation of cell redox state. Moreover, we studied the effect of adaptation to IHH and an antioxidant tempol on relative amount of calcium-independent phospholipase A2 (iPLA2). iPLA2 can remove peroxidized fatty acids from membrane phospholipids. On the other hand, iPLA2 can damage cell in I/R conditions. All enzymes were studied in homogenates from normoxic and IHH adapted rat left ventricular myocardium by Western blot. Adaptation to IHH caused a decrease of PRX6 and on the opposite an increase of...
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Thermisch induzierte Veränderungen von Inulin: Strukturelle und funktionelle Konsequenzen

Trabs, Kathrin 02 May 2013 (has links)
Die trockene, offene Erhitzung von Inulin im Bereich zwischen 100 und 220 °C resultiert in einem Abbau der Fructanketten. Dabei entsteht in Abhängigkeit vom pH-Wert ein weites Spektrum an Abbauprodukten, primär Mono- und Disaccharide, vorrangig Fructose und verschiedene Di-D-Fructose Dianhydride (DFDA). Da bisher nur ein DFDA als kommerzieller Standard erhältlich ist, wurden aus einem Inulinkaramell nach Aufreinigung per Flash-Chromatographie und semipräparativer HPLC-RI vier DFDA isoliert und identifiziert. Dabei handelt es sich um α-D-Fruf-1,2´:2,3´-β-D-Fruf (DFA III), α-D-Fruf-1,2´:2,1´-α-D-Fruf (DFA VII), β-D-Fruf-1,2´:2,1´-β-D-Fruf und α-D-Fruf-1,2´:2,1´-β-D-Fruf (DFA I). Eine fünfte Verbindung wurde als α-D-Fruf-1,2´-β-D-Fruf identifiziert, welches vermutlich aus α-D-Fruf-1,2´:2,6´-β-D-Fruf (DFA V) freigesetzt wird. Während unter sauren Bedingungen vor allem Fructose bestimmt wurde, kommt es unter basischen Erhitzungsbedingungen verstärkt zur Bildung löslicher, farbiger Verbindungen. Durch einen basischen Zusatz kann außerdem die antioxidative Wirksamkeit der Inulinkaramelle gesteigert werden, wobei wahrscheinlich besonders die farbigen Verbindungen für die antioxidative Wirkung verantwortlich sind. Die präbiotische Wirkung kann durch die Erhitzung nicht gesteigert werden, wird jedoch bei moderaten Erhitzungsbedinungen (etwa 160 °C) nicht verrringert. Durch eine gezielte Erhitzung kann Inulin so verändert werden, dass sich neue Eigenschaften und damit auch neue Einsatzmöglichkeiten in der Lebensmittelindustrie ergeben.
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Sinteza i fizičko-hemijska karakterizacija N-aromatičnih monosupstituisanih derivata karbohidrazona i tiokarbohidrazona / Synthesis and physicochemical haracterization of N-aromatic monosubstituted carbohydrazones аnd thiocarbohydrazones

Mrđan Gorana 25 September 2020 (has links)
<p>U ovoj doktorskoj disertaciji je radi fizičko-hemijske karakterizacije i ispitivanja potencijalne<br />biolo&scaron;ke aktivnosti sintetisano&nbsp; 40&nbsp; derivata mono(tio)karbohidrazona. Strukture dobijenih jedinjenja su potvrđene&nbsp; NMR&nbsp; i&nbsp; FT&ndash;IR&nbsp; spektroskopijom,&nbsp; elementalnom&nbsp; i&nbsp; rendgenskom&nbsp; strukturnom&nbsp; analizom. Uticaj&nbsp; rastvarača&nbsp; i&nbsp; prisutnog&nbsp; supstituenta&nbsp; na&nbsp; položaje apsorpcionih&nbsp; maksimuma&nbsp; ispitani&nbsp; su&nbsp; po principima LSER i LFER metoda. Teorijski proračuni za sintetisana jedinjenja izvedeni su&nbsp; primenom TD&ndash;DFT&nbsp; metode.&nbsp; Jonizacione&nbsp; konstante&nbsp; derivata&nbsp; mono(tio)karbohidrazona&nbsp; su&nbsp; određene potenciometrijskim&nbsp; titracijama.&nbsp; Antioksidativna&nbsp; aktivnost&nbsp; je&nbsp; određena&nbsp; primenom&nbsp; tri&nbsp; testa:&nbsp; DPPH, ABTS&nbsp; i&nbsp; FRAP&nbsp; testa.&nbsp; Antimikrobna&nbsp; aktivnost&nbsp; je&nbsp; ispitana&nbsp; mikrodilucionom&nbsp; metodom&nbsp; na&nbsp; dva&nbsp; soja bakterija:&nbsp; Staphylococcus&nbsp; aureus&nbsp; i&nbsp; Escherichia&nbsp; coli.&nbsp; Za&nbsp; jedinjenja&nbsp; koja&nbsp; su&nbsp; pokazali&nbsp; antimikrobnu aktivnost je&nbsp; ispitan procenat citotoksičnosti.&nbsp; Sveukupan&nbsp; zaključak o sličnosti i razlikama sintetisanih derivata izveden je na osnovu multivarijatnih metoda klaster analize i analize glavnih komponenti.</p> / <p>In this doctoral dissertation, 40 mono(thio)carbohydrazone derivatives were synthesized for the purpose of physico-chemical characterization and examination of potential biological activity. The structures of the obtained compounds were confirmed by NMR and FT &ndash;IR spectroscopy, elemental analysis&nbsp; and&nbsp; X-ray&nbsp; structural&nbsp; analysis.&nbsp; The&nbsp; influence&nbsp; of&nbsp; solvent&nbsp; and&nbsp; substituent&nbsp; present&nbsp; on&nbsp; the positions&nbsp; of&nbsp; absorption maxima&nbsp; was&nbsp; examined&nbsp; according&nbsp; to&nbsp; the&nbsp; principles&nbsp; of&nbsp; LSER&nbsp; and&nbsp; LFER methods.&nbsp; Theoretical&nbsp; calculations&nbsp; for&nbsp; the&nbsp; synthesized&nbsp; compounds&nbsp; were&nbsp; performed&nbsp; by&nbsp; the&nbsp; TD&ndash;DFT method.&nbsp; The&nbsp; acid&nbsp; constants&nbsp; of&nbsp; mono(thio)carbohydrazone&nbsp; derivatives&nbsp; were&nbsp; determined&nbsp; by potentiometric&nbsp; titrations.&nbsp; Antioxidant&nbsp; activity&nbsp; was&nbsp; determined&nbsp; using&nbsp; three&nbsp; tests:&nbsp; DPPH,&nbsp; ABTS&nbsp; and FRAP test. Antimicrobial activity was examined by microdilution method on two strains of bacteria: Staphylococcus&nbsp; aureus&nbsp; and&nbsp; Escherichia&nbsp; coli.&nbsp; The&nbsp; percentage&nbsp; of&nbsp; cytotoxicity&nbsp; was&nbsp; examined&nbsp; for compounds&nbsp; that&nbsp; showed&nbsp; antimicrobial&nbsp; activity.&nbsp; Overall&nbsp; conclusion&nbsp; about&nbsp; the&nbsp; similarities&nbsp; and differences of the synthesized&nbsp; derivatives was studied by multivariate&nbsp; methods of cluster analysis and analysis of principal components.</p>

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