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1	Alkaloidy Centaurea cyanus L. (Asteraceae) a jejich biologická aktivita vztažená k Alzheimerově chorobě / Centaurea cyanus L. (Asteraceae) alkaloids and their biological activity related to Alzheimer's disease Drabbová, Adriana January 2020 (has links) Drabbová, A.: Title of Diploma Thesis: Centaurea cyanus L. (Asteraceae) alkaloids and their biological activity related to Alzheimer's disease. Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany, Hradec Králové 2020. Ethyl acetate and chloroform alkaloids extracts were prepared from Centaurea cyanus L. seeds. A novel alkaloid AD-1 (Adrabbin) was isolated from the ethyl acetate extract by common chromatografic methods (column chromatography, preparative TLC). Its structure was elucidated by mass spektrometry, NMR analysis and determination of optical rotation. The alkaloid AD-1 (Adrabbin) possesses a unique structure which consists of a cyclic indole moiety. Also LC-MS analysis of fractions obtained by flash chromatography was performed. In those fractions were detected molecular ions related to compounds previously isolated from other Centaurea species. Alkaloid AD-1 (Adrabbin) was tested on ability to inhibit human cholinesterases, prolyl oligopeptidase and gylcogen synthase kinase 3β. The compound was considered against human cholinesterases inactive (IC50 values > 100 µM). Interestibgly, the alkaloid inhibited prolyl oligopeptidase the same intensity as a standard berberine (AD-1: IC50 143,0 ± 6,0 µM; berberin: IC50 142,0 ± 21,0 µM). The novel compound...
2	Examining the competitive abilities of cornflower (Centaurea cyanus) in a growth chamber experiment. / Studie av den relativa konkurrensförmågan hos blåklint (Centaurea cyanus) odlad i växtkammare. Karlsson, Emil January 2019 (has links) Competition between different species (interspecific competition) is an important factor to consider when estimating population trends, geographic distributions, and management options of species. Many historically common vascular plant species found in agricultural environments have been negatively affected by changes in community composition and in turn, changes in competition pressures. Even so, the relative importance of plant competition in an ecological context is still unclear. In this study I examine the competitive ability of the meadow plant cornflower (Centaurea cyanus L.) when grown together with common oat (Avena sativa) and common poppy (Papaver rhoeas), during a seven-week long growth chamber experiment. Seeds were sown in pots in four different setups; 1) C. cyanus control, 2) C. cyanus + P. rhoeas, 3) C. cyanus + A.sativa, 4) All three species. Six different growth parameters were measured (aboveground dry-weight, belowground dry-weight, root length, leaf area, number of leaves and above/belowground dry-weight ratio). I found that growth rates of C. cyanus were significantly inhibited according to all six growth parameters when C. cyanus competed solely with A. sativa. Competition from P. rhoeas had an insignificant effect on C. cyanus growth in five out of six growth parameters. Finally, I discuss the possibility that historically common meadow plants have declined in abundance in part because of weak competitive abilities, and that rare vascular plant species are negatively affected by growing in proximity with cereal crops. Centaurea cyanus Papaver rhoeas Avena sativa Cornflower Growth chamber Plant competition Plant ecology LAI Root biomass Root length Biomass Dry weight Interspecific competition Blåklint Kärlväxter Konkurrensförmåga Ekologi Ecology Ekologi
3	Multifaceted effects of competition and plant-soil feedbacks on Achillea millefolium grown in soil from a riparian meadow : Emil Karlsson - Umeå University - Thesis project - 60 hp Karlsson, Emil January 2021 (has links) Competition between plant individuals and how plants alter soil properties are key processes which drive changes in plant communities over time. Estimating the relative importance of these processes and how they affect plant growth in different ecological contexts and communities is an active area of research. Furthermore, interdependencies between the two processes have been suggested to occur in many cases, but research in this area is also lacking. In this study, soil conditioned by common yarrow (Achillea millefolium) was collected from field plots and was then used in a growth chamber competition experiment, which controlled for plant-soil feedbacks. Measured soil properties such as soil pH, soil nitrogen, and soil texture were primarily used as background data in the experiment. Field parameters such as light availability, plant density, and grass to forbs ratio were used to predict optimal A. millefolium habitat in relation to other vascular plant species. The results indicate that A. millefolium was a weaker competitor than cornflower (Centaurea cyanus), while a positive plant-soil feedback effect was observed by A. millefolium grown in field soil. Intraspecific competition had a strong negative effect on A. millefolium growth when grown in non-conditioned soil, but not when grown in A. millefolium conditioned soil. Finally, competition and plant-soil feedbacks appeared to be additively affecting A. millefolium growth, meaning the plant-soil feedback effect did not have a disproportionate effect on competitive outcomes, or vice versa. The findings of this study can be of interest to conservationists or farmers who wish to predict how plant communities respond to plant competition and plant-soil feedbacks as processes. Plant Competition Plant soil feedback Yarrow Achillea millefolium Centaurea cyanus Soil pH Nitrate Ammonium Nitrogen Soil texture Light Sweden Height Biomass Field Growth chamber Greenhouse Ecology Relative fitness Stabilizing niche Konkurrens Jordmån Kärlväxter Röllika Blåklint Ecology Ekologi

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