National Repository of Grey Literature 8 records found  Search took 0.00 seconds. 
Biologicky významné látky v bylinných čajích u čeledi hvězdnicovité
Stejskalová, Lenka
The importance of herbs and herbal teas is a frequently researched topic due to the content of biologically active substances. Plant material is a source of a large number of diverse components, which are proven to have a beneficial effect on the human organism. These substances are able to help in the prevention and possibly treatment of some human diseases. To fully understand the function of individual plants, it is necessary to know the content of individual groups of biologically active substances. The first part of this master's thesis named Biologically Important Substances in Herbal Teas of the Family Asteraceae escribes and defines herbal teas and organic farming. It also describes the Asteraceae family and focuses more specifically on selected species within this family, including marigold (Calendula officinalis), chamomile (Matricaria chamomilla L.), coltsfoot (Tussilago farfara L.) and coneflower (Echinacea purpurea). The consumption of herbal teas is currently high and still growing, therefore it is necessary to know the composition of the used plants. Representatives were chosen for their popularity and abundant use in the preparation of herbal teas. For each representative, there is a short botanical description and description of the contained substances. In the next chapter of the theoretical part, phenolic substances, their determination and effect on human health are presented. The group of flavonoids, which is a subgroup of phenolic substances, is described in more detail. The last section of the theoretical part explains the concepts of antioxidants, free radicals and methods of determining antioxidant activity. These groups were selected for measurement because they are substances showing effect on human health. In the practical part of this work, the total content of polyphenols, the total content of flavonoids and the total antioxidant capacity are determined in selected species. All these groups are determined spectrophotometrically. The essence of this work was to find out whether the content of these compounds in the same in samples from different productions. For each representative, one sample originating from organic farming (known as “BIO“) and one sample originating from conventional agriculture are examined. These two samples were statistically compared.
Species and cytotype diversity of invasive Symphyotrichum species in Central Europe
Varvažovská, Adéla ; Slovák, Marek (advisor) ; Hodálová, Iva (referee)
The cytotypic variability of Aster species of the genus Symphyotrichum is relatively well-explored within the territory of North America, where this species originates. Unfortunately, in Europe, where Asters were originally introduced as ornamental plants, they have received limited attention in terms of their overall as well as cytotypic variability. The number of publications and data concerning cytotypic variability and karyology in Europe is very limited, with some reporting the occurrence of several species and higher ploidy level species complexes. Asters naturalize in many places, capable of reproducing both vegetatively and generatively, and primarily colonize habitats disturbed by human activities. As a result, they have been classified as invasive plant species. From a biosystematic perspective, Asters constitute a highly complex group due to their high morphological and karyological variability. This situation is further complicated by the phenomenon of polyploidy and intense interspecific and intraspecific hybridization. These factors contribute to the challenging task of identifying individuals and populations and assigning them to specific taxa. The aim of this thesis was to clarify the cytotypic variability of wild-growing Aster species of the genus Symphyotrichum (Asteraceae) in the...
The relationship between genetic and ploidy variation in the context of differing ecological conditions of two species of the genus Pteronia (Asteraceae) in the Cape
Havlíčková, Eliška ; Chumová, Zuzana (advisor) ; Záveská, Eliška (referee)
The genus Pteronia is an example of a recently radiated and taxonomically complicated genus of the family Asteraceae (sunflower family) with endemic connection to southern Africa. Most of the species are associated with the Cape region, an area characterised by a Mediterranean type of climate, which is comparable in species richness to the flora of tropical areas, especially on smaller geographical scales. The factors behind the high diversity of the Cape are environmental heterogeneity, climatic stability (low extinction and accumulation of species) and regular disturbance by fire. Polyploidization, one of the main mechanisms of plant evolution, has been an overlooked and denied phenomenon in the Cape for a long time. Individual cases of polyploidy are being revealed, but the causes of their emergence and extent of their occurrence are unknown. The presented work focuses on polyploidization in the genus Pteronia from the perspective of two species with different ecological valence. On the widespread to invasive species Pteronia incana and, on the contrary, on the endemic species of succulent karoo and deserts, Pteronia glabrata. Using flow cytometry, genome size variation was investigated and ploidy levels determined. The obtained cytometric data were used to compare climatic, topographic,...
Centaurea cyanus L. (Asteraceae) alkaloids and their biological activity related to Alzheimer's disease
Drabbová, Adriana ; Chlebek, Jakub (advisor) ; Opletal, Lubomír (referee)
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...
The cytotype diversity and population demography of invasive aster from Symphyotrichum lanceolatum a S. novi-belgii groups in Central Europe.
Varvažovská, Adéla ; Slovák, Marek (advisor) ; Chrtek, Jindřich (referee)
Asters from Symphyotrichum lanceolatum and S. novi-belgii a species complexes are native to North America from where they were imported to Europe as ornamental plants during the 19th century. They were naturalized and later became invasive in the humid habitats along rivers and lakes. Both species groups are karyologically and morphologically highly variable what is reflected in their complex taxonomy. A crucial role in the formation of their intricated diversity play inter- and intraspecies hybridization, polyploid evolution as well as phenotypic plasticity. The biological and ecological diversity of Asters was thoroughly studied in their natural environment in North America, however only little is known about their variability in their new, invaded European habitats. Numerous polyploid cytotypes were reported from their native distribution range in North America, however, only a single cytogeographic study in Europe has been published to date. The outcomes of this study accompanied by occasional chromosome counts indicated the existence of higher ploidy levels only. Specifically hexaploid and octoploid cytotype was reported for S. lanceolatus while hexaploids in S. novi-belgii. The problem of the karyological variability of these taxa in Europe deserves attention and further research. Key words:...
Centaurea cyanus L. (Asteraceae) alkaloids and their biological activity related to Alzheimer's disease
Drabbová, Adriana ; Chlebek, Jakub (advisor) ; Opletal, Lubomír (referee)
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...
Seasonal variability of plant secondary metabolism (Artemisia sp.)
Koutská, Barbora ; Weiser, Martin (advisor) ; Dostál, Petr (referee)
Plant secondary metabolites (SM) are widely used by humans in many ways (pharmacy, biotechnology etc.). For making their use even more effective, it is important to know the seasonality of these chemicals in plants and what affect those changes. Three Artemisia species (Artemisia annua, A. absinthium, A. vulgaris) were cultivated during one vegetation season (from April to September 2016). Plant growth parameters and the beginning of their generative stages were observed, and leaf samples were collected regularly. Samples of some plants were collected repeatedly. A generalist herbivore (migratory locust), was used as a proxy for studying changes in plant secondary metabolism during the vegetation season. The results proved presence of defence secondary metabolites in plants except A. vulgaris species where the role of SM in defence was not shown. Levels of SM changed nonlinearly during the vegetational season and were time-dependent. Plant size did not influence the levels of SM in plants. Levels of SM were low at the beginning of the experiment followed by rapid increase and remaining on maximal levels. The plants which lost their biomass repetitively grew slowly and bloomed later than the plants which were clipped only once. A delay trend showing seasonality of the plant SM was not proved. In...

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