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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

Physiological and Biochemical Responses of Three Echinacea Species to Salinity Stress

Sabra, Ali 04 1900 (has links)
To determine the level of salt tolerance of the medicinal plant Echinacea, the physiological and biochemical characteristics of E. purpurea, E. pallida and E. angustifolia exposed to different NaCl levels (0, 50, 75, and 100 mM) were evaluated under hydroponic culture. Dry weights of shoots and roots were not affected by salinity; however E. purpurea and E. pallida exhibited higher survival rate than E. angustifolia, which also showed high salt injury index and electrolyte leakage compared to the other two species. Gas exchange (photosynthetic rate, stomatal conductance, and transpiration rate) showed a decline with increasing salt concentrations in all species with a more pronounced reduction in E. angustifolia. E. purpurea was able to retain more Na+ in the roots than the other two species showing its capacity to regulate Na+ translocation to shoots (Na+ exclusion). Moreover, the activities of two major antioxidant enzymes; superoxide dismutase (SOD) and ascorbate peroxidase (APX) were increased by salinity in E purperea, while the activities were decreased in E. angustifolia. The characteristic phytochemical profiles of caffeic acid derivatives (CADs) and alkamides/ketones were obtained for the three species, and quantitative changes were determined. Cichoric acid, the major CAD in E. purpurea, was increased with salinity up to 75 mM NaCl. A relative increase in alkamides and CADs was recorded in E. angustifolia, while in E. pallida, the level of echinacoside and major ketones (22 and 24) decreased, suggesting that the medicinal value of this species was compromised by salt stress. First evidence of salt-induced changes in alkamides and ketones in Echinacea was demonstrated in this study. Activity of phenylalanine ammonia-lyase (PAL), the major enzyme involved in the biosynthesis of CADs, was increased only in the roots of E. purpurea, further reflecting the differences in salt tolerance between species. It can be concluded that Echinacea species exhibited a limited degree of salt tolerance; however, E. purpurea showed a higher tolerance than E. pallida and E. angustifolia. This tolerance was mainly attributed to the increase in Na+ exclusion capacity, antioxidant activities and PAL activity.
2

Physiological and Biochemical Responses of Three Echinacea Species to Salinity Stress

Sabra, Ali 04 1900 (has links)
To determine the level of salt tolerance of the medicinal plant Echinacea, the physiological and biochemical characteristics of E. purpurea, E. pallida and E. angustifolia exposed to different NaCl levels (0, 50, 75, and 100 mM) were evaluated under hydroponic culture. Dry weights of shoots and roots were not affected by salinity; however E. purpurea and E. pallida exhibited higher survival rate than E. angustifolia, which also showed high salt injury index and electrolyte leakage compared to the other two species. Gas exchange (photosynthetic rate, stomatal conductance, and transpiration rate) showed a decline with increasing salt concentrations in all species with a more pronounced reduction in E. angustifolia. E. purpurea was able to retain more Na+ in the roots than the other two species showing its capacity to regulate Na+ translocation to shoots (Na+ exclusion). Moreover, the activities of two major antioxidant enzymes; superoxide dismutase (SOD) and ascorbate peroxidase (APX) were increased by salinity in E purperea, while the activities were decreased in E. angustifolia. The characteristic phytochemical profiles of caffeic acid derivatives (CADs) and alkamides/ketones were obtained for the three species, and quantitative changes were determined. Cichoric acid, the major CAD in E. purpurea, was increased with salinity up to 75 mM NaCl. A relative increase in alkamides and CADs was recorded in E. angustifolia, while in E. pallida, the level of echinacoside and major ketones (22 and 24) decreased, suggesting that the medicinal value of this species was compromised by salt stress. First evidence of salt-induced changes in alkamides and ketones in Echinacea was demonstrated in this study. Activity of phenylalanine ammonia-lyase (PAL), the major enzyme involved in the biosynthesis of CADs, was increased only in the roots of E. purpurea, further reflecting the differences in salt tolerance between species. It can be concluded that Echinacea species exhibited a limited degree of salt tolerance; however, E. purpurea showed a higher tolerance than E. pallida and E. angustifolia. This tolerance was mainly attributed to the increase in Na+ exclusion capacity, antioxidant activities and PAL activity.
3

Stanovení obsahových látek rostliny Echinacea / Analysis of Echinacea content compounds

Michalíček, Jan January 2008 (has links)
Rostliny rodu Echinacea jsou léčivé byliny stimulující imunitní systém. Používají se zvláště v boji proti chřipce a infekcím horních cest dýchacích. V této práci bylo analyzováno 7 komerčních výrobků obsahujících výtažky z rostliny Echinacea vysokoúčinnou kapalinovou chromatografií. Bylo provedeno kvantitativní stanovení derivátů kyseliny kávové, jež jsou látky zodpovědné za léčivé účinky rostliny. Zjištěné obsahy kyseliny chlorogenové, kávové, cichorové a echinakosidu byly porovnány v jednotlivých výrobcích. Dále byly připraveny extrakty z kořene, listů a květů třapatky nachové pomocí extrakce za zvýšeného tlaku extrakčního rozpouštědla při různých podmínkách, aby se z obsahu účinných látek v nich přítomných zjistilo, které extrakční podmínky jsou nejlepší. Z naměřených dat bylo zjištěno, že největší celková koncentrace obsahových látek je přítomna ve výrobku Imunit Echinaceové kapky firmy Simply You. Jako nejlepší extrakční podmínky se ukázaly teplota 80 °C v kombinaci s rozpouštědlem ve složení EtOH/voda = 40/60, a to jak při extrakci kořene, tak i listů a květů.
4

Intraspezifische Variabilität und Einflüsse von Anbaumaßnahmen auf den Inhaltsstoffgehalt und Ertrag von Solidago virgaurea L.

Lück, Lorna 03 August 2001 (has links)
Mit den vorgestellten Untersuchungen sollten das Potential der in Europa vorkommenden Echten Goldrute für den Anbau evaluiert und der Einfluß von Erntetermin, Schnitthöhe und Düngungsmaßnahmen sowie der abiotischen Umweltfaktoren Licht und Wasser auf den Ertrag und den Inhaltsstoffgehalt von Solidago virgaurea L. geprüft werden. In vier Feldversuchen wurden Inhaltsstoffgehalte, Ertragsparameter, Entwicklungsstadien sowie morphologische Merkmale untersucht. Die Gehalte an Flavonolglycosiden, Phenolglucosiden und Kaffeesäurederivaten wurden mittels HPLC und nachfolgender DAD-Detektion bestimmt. 45 Akzessionen aus dem europäischen Verbreitungsgebiet wurden anhand ihres Blühtermines gegliedert, den Unterarten virgaurea und minuta zugeordnet, und mit Hilfe von 33 morphologischen Merkmalen charakterisiert. Die Analyse von 452 Einzelpflanzen ergab Spannweiten von 0.4 bis 2.4 % Flavonolglycosiden, 0.7 bis 4.6 % Kaffeesäurederivaten und 0 bis 1.6 % Phenolglucosiden. Die phytochemische Zusammensetzung war innerhalb der einzelnen Akzessionen, insbesondere in der Unterart virgaurea hoch variabel. In einer anbaubezogenen Gesamtbewertung der Akzessionen erwiesen sich Herkünfte der Unterart virgaurea aufgrund hoher Drogenerträge von maximal 109 dt/ha und eines ausgewogenen Inhaltsstoffspektrums als die Wertvollsten. Im Lauf der Ontogenese stieg der Drogenertrag der Echten Goldrute an, während die Inhaltsstoffgehalte schwankten (Kaffeesäurederivate, Flavonolglycoside) oder relativ kontinuierlich absanken (Phenolglucoside). Eine gehaltsorientierte Ernte müßte daher zum relativ frühen Zeitpunkt des mittleren Knospenstadiums erfolgen. Hohe Masse- und Inhaltsstofferträge sind in einem Ernteverfahren mit niedrigen Schnitthöhen von 15 bis 30 cm erreichbar. In voll besonnten Pflanzen wurde im Vergleich zu schattierten eine höhere Anreicherung von Flavonolglycosiden und Kaffeesäurederivaten festgestellt, die durch die UV-Schutzfunktion dieser Stoffgruppen erklärbar ist. Daher muß angenommen werden, daß ontogenetisch bedingte Gehaltsveränderungen der Flavonolglycoside und Kaffeesäurederivate durch unterschiedliche Strahlungsverhältnisse überlagert werden können. Stickstoffdüngung verursachte neben der erwarteten ertragssteigernden Wirkung Unterschiede im Inhaltsstoffgehalt. In der ungedüngten Variante wurden jeweils die höchsten Flavonolglycosidgehalte bestimmt, gefolgt von der organischen Düngung sowie der Mehrnährstoff- und Stickstoffdüngung. Während die ermittelten Stickstoff- (maximal 96 kg/ha N) und Phosphorentzüge (maximal 39 kg/ha P2O5) vergleichsweise gering waren, wurden Kaliumentzüge (maximal 172 kg/ha K2O) festgestellt, die auch im Vergleich zu anderen Blatt- und Krautdrogen relativ hoch ausfielen. Im Gesamtüberblick aller Einflüsse wurde deutlich, daß Flavonolglycoside, gefolgt von Kaffeesäurederivaten am empfindlichsten auf Umwelteinflüsse wie Lichteinstrahlung und Nährstoffverfügbarkeit reagierten, während die Gruppe der Phenolglucoside nur geringe Schwankungen zeigte. Die Ergebnisse aller Versuchsfragen spiegeln das Spannungsfeld von landwirtschaftlichem Ertrag und pharmazeutisch geforderter Qualität wider, die häufig negativ korreliert sind. Bei der Produktion der Droge von Echter Goldrute muß daher eine Balance zwischen beiden Zielgrößen gefunden werden. / The aim of the presented studies was to evaluate the potential for cultivation of the European Goldenrod (Solidago virgaurea L.) and to examine the influences of harvesting date, cutting height, fertilization and of the abiotic environmental factors light and water on drug yield and compound content of the plant. In four field trials a fingerprint of 10 constituents, several parameters of drug yield, development stages and morphological traits were examined. The contents of flavonol glycosides, phenolic glucosides and caffeic acid derivatives were determined by HPLC and UV-detection by DAD. 45 european accession were sorted by their dates of anthesis and subdivided into the subspecies virgaurea and minuta and thereafter characterized by 33 morphological traits. The analysis of 452 individual plants showed ranges of 0.4 to 2.4 % flavonol glycosides, 0.7 to 4.6 % caffeic acid derivatives and 0.0 to 1.6 % phenolic glucosides. Within the examined accessions, especially subspecies virgaurea, a high variability of the phytochemical composition was observed. In an evaluation, accessions of subspecies virgaurea turned out to be most suitable for cultivation due to high drug yields up to 106 dt per ha and well-balanced spectra of constituents. During ontogenesis the drug yield of S. virgaurea increased, while compound contents varied (caffeic acid derivatives, flavonol glycosides) or decreased continuously (phenolic glucosides). Therefore a harvest aiming at high compound contents has to be carried out at a early development stage of mid budding. High mass and constituent yields can be obtained by a harvesting method with low cutting heights of 15 to 30 cm above ground. Plants in a sunny environment accumulated significantly higher amounts of flavonol glycosides and caffeic acid derivatives than shaded plants, which can be explained by the UV-protective function of these compound groups. Therefore it can be concluded that phytochemical variations during ontogenesis could be modified by different light conditions. Beside the expected drug yield increase, fertilization with nitrogen caused differences in the compound contents. The highest flavonol glycosides contents were observed in the unfertilized treatment, followed by treatments with organic fertilization, multinutrient fertilizer and calcium ammonium nitrate. While the nitrogen uptake by the plant (maximal 96 kg/ha N) and phosphorus (maximal 39 kg/ha P2O5) were relatively low, contrary potassium uptake (maximal 172 kg/ha K2O) was relatively high compared to other herbal drugs. In an overview of all influences it became obvious that the reaction of flavonol glycosides and caffeic acid derivatives were relatively sensitive to environmental influences such as light conditions and nutrient availability, while the group of phenolic glucosides showed low variations. The results of all field trials reflect the conflict between agricultural yield and pharmaceutical quality which are frequently negatively correlated. Therefore a balance between these two goals has to be found during drug production of S. virgaurea.

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