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Verf.: Franziska Fuchs Zsfassung in engl. Sprache Wien, Univ. für Bodenkultur, Masterarb., 2012

Ill., graph. Darst.

Tannine sind pflanzliche, polyphenolische Sekundärmetabolite mit Protein-präzipitierenden und –bindenden Kapazitäten, welche offenbar für die antinutritiven und gesundheitsschädlichen Wirkungen der Tannine verantwortlich sind. Jedoch dominieren in der Literatur die gesundheitsfördernden Beschreibungen, für die meist die antioxidative Kapazität verantwortlich gemacht wurde. Der etablierte Modelorganismus Caenorhabditis elegans wurde zur Analyse dieses Kontrastes ausgewählt. Zunächst wurden Lebensdauer und Stressresistenz der mit Tanninsäure und den Tanninbausteinen Gallussäure, Ellagsäure und Catechin behandelten Nematoden ermittelt. Das vermutete Vorliegen eines „Calorie Restriction“ (CR)-Effektes als auch einer hormetischen Dosis-Wirkungs-Beziehung wurde überprüft. Weiterhin wurden antimikrobielle und antioxidative Eigenschaften als potentielle Ursachen der Langlebigkeit untersucht und die Auswirkungen auf die Fitness und Genexpression analysiert. Die Einbeziehung verschiedener Alterungs-Theorien rundete die Analyse der Tanninwirkung ab. Alle Tannin-Substanzen konnten eine Lebensverlängerung erwirken, doch erstaunlicherweise erwiesen sich Langlebigkeit und Stressresistenz als individuelle, nicht zwangsläufig gekoppelte Parameter. Hormesis, CR-nachahmende Eigenschaften, antimikrobielle Kapazitäten als auch verschiedene stressrelevante Gene sind teilweise für die Lebensverlängerung verantwortlich. Die antioxidative Kapazität scheint jedoch irrelevant zu sein. Die differentielle Expression mehrerer hundert Gene durch Tanninsäure unterstreicht zudem die Komplexität der Wirkweise. Hinweise zur Bestätigung der „Disposable Soma Theory“, der „Mitohormesis“-Theorie und der „Green Theory of Ageing“ konnten zum Teil gefunden werden. Diese Arbeit zeigt die individuelle und kontrastreiche Wirksamkeit der Tannine auf. Sie unterstreicht, dass Tannine molekulare Regulatoren sind, welche nicht nur auf ihre antioxidative und antinutritive Kapazität reduziert werden sollten. The polyphenolic tannins are plant-produced secondary metabolites with protein precipitating and binding capacities. This characteristic is seemingly responsible for antinutritional and harmful effects. However, health benefits have also been extensively described in the literature. Indeed, antioxidant properties are believed to be the reason for these beneficial effects. The established model organism Caenorhabditis elegans was chosen to examine this apparent contradiction. The nematodes were exposed to tannic acid and to the tannin building blocks gallic acid, ellagic acid, and catechin and the lifespan and stress resistance were determined. The presence of a calorie restriction (CR) effect and a hormetic dose-response-relationship was verified. Furthermore, antimicrobial and antioxidative capacities were assessed as possible causes of longevity and the impact on fitness parameters and gene expressions was analysed. The consideration of different ageing theories completed the analysis of the tannin action. All tannin-substances were able to prolong the lifespan but against all expectations, longevity and stress resistance were shown to be independent entities, which are not necessarily linked. Hormesis, CR-mimetic properties, antimicrobial capacities as well as several stress relevant genes are partly responsible for the life-extension. The antioxidant capacities, however, appeared to be irrelevant. The regulation of several hundred gene expressions by tannic acid underlined the complexity of the mode of action. Furthermore, the results partly confirm the “Disposable Soma Theory”, the “Mitohormesis Theory” and the “Green Theory of Ageing”. This work dissects the contrasting efficiency of the tannin family and underlines in particular, that tannins are molecular regulators, which should not be reduced to their antioxidative and antinutritional capacities

In der vorliegenden Arbeit wird einStressreduktionsprogramm der Feldenkrais-Methode qualitativ mit Hilfe des "persönlichen Gesprächs" nach einem 4 Tages-Workshop evaluiert. Es konnte eine Stress- und Angst reduzierende Wirkung nachgewiesen werden. Die Teilnehmer erfuhren einen neuen Umgang mit sich selbst, bewerteten bisherige Stressituationen neu und entdeckten neue entlastende Verhaltensmöglichkeiten im Alltag.

Plants are able to emit flavours over their flowers, leaves and fruits. These flavours serve them as attractants, repellents or signal molecules. Many plants show a constitutive emission of a series of different mono- and sesquiterpenes. Futhermore plants have also inducible emissions. The influence of stressors like e.g. predators, bacteria, fungi or ozone yield to novel synthesis and emission of repellents and signal molecules. They originate mainly form octadecanoid and sikimate pathway. The octadecanoid pathway yields in the formation of alcohols and aldehyds (predominatly C6-compounds). Starting form free fatty acids they were generated and emitted via an enzyme cascade (lipase, lipoxygenase, hydroperoxidelyase). The Shikimat pathway is important for the formation of the important plant hormone salicylic acid (SA). After methylation SA can be emitted as the volatile methylsalicylate MeSA) into the atmosphere. The main task of the work was to approve if it is possible to draw conclusions from stress induced emissions to certain plant internal enzyme activities or substrate concentration in the model plant tomato (cv. Moneymaker). The would allow a non invasive measurement of such endogenous parameters. On the one hand it should be proved if the emission of green leave aldehyds and alcohols (GLAs) can be suitable for the prediction of the enzyme activities lipase, lipoxygenase and hydroperoxidelyase or the substrate concentrations in the octadecanoid pathway. The GLAs were measured by online GC/MS, the intermediates (free fatty acids, hydroperoxy fatty acids)by HPLC and the enzyme activities by UV/VIS spectroscopy. A good correlation between a certain enzyme activity/substrate concentration should then be a hint to the rate-determining step in the cascade. On the other hand it should be proved if emission of MeSA can be suitable for the prediction of endogenous free SA concentration. Also in this case I looked for a correlation between the MeSA emission and the plant internal SA concentration. The measurement of MeSA were measured by online GC/MS as well and the endogenous SA concentrations by HPLC. Ozone exposure and infection by fungi (Botrytis cinerea) were used as abiotic/biotic stressors respectively. The stress response on ozone exposure of the tomato plants started with varying lag times between 1 and 3 hours. The plants reacted with the emission of methanol, GLAs and MeSA as well as increasing of the emissions of mono- and sesquiterpenes. The plants were removed from the chamber, snap frozen and homogenised with pistil and mortar and stored at -80°C until the extraction and measurement of the enzyme activities/SA concentrations respectively. Whereas the GLA emissions showed no good correlations with lipase and hydroperoxidelyase activities (0.19 and 0.41) the correlation with the lipoxygenase activity was quite good (0.82). This points to the lipoxygenase to be the rate-determining step for the GLA emission. Free fatty acids were found in similar concentrations both in control plants and stressed plants. Substrate limitation by low availability of free fatty acids hence seems not to be ratedetermining. The concentration of hydroperoxy fatty acids were always beyond the detection limit, therefore the lack of substrate for the hydroperoxidelyase may be the "bottle neck" for the GLA emission strength. Also this substrate limitation should lead to a good correlation between GLA emission and lipoxygenase activity. Due to this good correlation it is in cases of Botrytis infection and ozone fluxes between 3•10-8 and 8•10-8 mol m-2 s-1 possible to predict internal enzyme activities by measurement of the GLA emissions. However the GLA emission are not in all cases sufficient to predict the lipoxygenase activity without restrictions. In particular high ozone fluxes into the plant yielded in very high GLA emissions and strong variances form the linear correlation between emission and lipoxygenase activity occurred. Also the emission of MeSA and the internal concentration of free SA showed a good correlation (0.91). Though it should possible to estimate the endogenous free SA concentration by measuring the MeSA emission. All in all this work shows that it is possible to conclude different plant internal enzyme activities and amounts of substances using the measurement of volatile compounds. Though these emissions allow the not invasive determination of these parameters in a good demand interval.

Ill., graph. Darst.

Ill., graph. Darst.