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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.
41

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...
42

Alkaloidy Vinca minor L. a jejich biologická aktivita VIII. / Vinca minor L. alkaloids and their biological activity VIII.

Hojgrová, Veronika January 2021 (has links)
V. Hojgrová: Alkaloids of Vinca minor L. and their biological activity VIII. Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany. Number of pages 69. This diploma thesis deals with the isolation of alkaloids from Vinca minor L. from the family Apocynaceae. Separation of alkaloids from the selected fraction (VM 215-258) or from their subfractions (VM 34-41, VM 86, VM 87-113) was performed by preparative TLC. Two pure alkaloids were isolated from the subfraction (VH 34-41). The first VH-1 alkaloid not yet isolated and the second VH 2 alkaloid: (-)-raucubainin. Alkaloids were identified by EI-MS, LC-MS, NMR and optical rotation and were compared with data in the literature. Isolated alkaloids were tested for acetylcholinesterase (AChE), butyrylcholinesterase (BuChE) and prolyloligopeptidase (POP) inhibitory activity and for cytotoxicity. Both substances did not show significant cholinesterase inhibitory activity IC50 against AChE after measurement, only (-)-raucubainin showed a slight activity against BuChE (IC50 = 94 ± 7 μM), VH-1 was found to be inactive (IC50 > 100 μM). POP inhibitory activity has so far only been tested for (-)-raucubainin; was found to be inactive (IC50 > 1000 µM). The results of the cytotoxic activity of the alkaloids...
43

Studium biologické aktivity alkaloidů izolovaných z Argemone grandiflora (Papaveraceae)I. / Study of biological activity of isolated alkaloids from Argemone grandiflora (Papaveraceae)I.

Adamcová, Markéta January 2015 (has links)
Adamcová, M.: Study of biological activity of alkaloids isolated from Argemone grandiflora (Papaveraceae) I. Diploma thesis, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové 2015. The aim of this study was isolation of substances from total diethyl ether alkaloid extract of Argemone grandiflora Sweet, their identification and assessment of their inhibition activity towards acetylcholinesterase, butyrylcholinesterase and prolyl oligopeptidase. Using common chromatografic methods, four alkaloids were isolated, that was identified as (+)-laudanosine, protopine, (-)-argemonine a (-)-platycerine. These substances was tested for their inhibition activity IC50: (+)-laudanosine (IC50 AChE = 617,00 ± 46,55 μM, IC50 BuChE = 644,77 ± 55,52 μM, IC50 POP = not mesured yet); protopine (IC50 AChE = 229,98 ± 21,02 μM, IC50 BuChE = 208,87 ± 17,67 μM, IC50 POP ˃ 1000 μM); (-)-argemonine (IC50 AChE = 4677,75 ± 1241,08 μM, IC50 BuChE = 885,45 ± 119,50 μM, IC50 POP = 337 ± 83,1 μM); (-)-platycerine (IC50 AChE = 223,65 ± 19,61 μM, IC50 BuChE = 1651,25 ± 327,7 μM, IC50 POP = 687 ± 74 μM). In comparison with the standards galanthamine (IC50 AChE = 1,710 ± 0,065 μM, IC50 BuChE = 42,30 ± 1,30 μM) and huperzine A (IC50 AChE = 0,033 ± 0,001...
44

Biologická aktivita obsahových látek rostlin XXVIII. Alkaloidy vybraných odrůd taxonu Narcissus cyclamineus REDOUTÉ a jejich účinek na acetylcholinesterasu a butyrylcholinesterasu. / Biological activity of plant metabolites XXVIII. Alkaloids from selected cultivars of Narcissus cyclamineus REDOUTÉ and their influence on acetylcholinesterase and butyrylcholinesterase

Janura, Michal January 2015 (has links)
Biological activity of plant metabolites XXVIII. Alkaloids from selected cultivars of Narcissus cyclamineus REDOUTÉ and their influence on acetylcholinesterase and butyrylcholinesterase. JANURA M.: Diploma work, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové 2015, Czech Republic. Abstract: The summary extracts of alkaloids from bulbs of N. cyclamineus esp. N. cyclamineus cv. Jenny, N. cyclamineus cv. Little Witch, N. cyclamineus cv. Rapture, N. cyclamineus cv. Surfside, N. cyclamineus cv. Peeping Tom, N. cyclamineus cv. Warbeld and N. cyclamineus cv. Skater's Waltz were obtained by the procedures common for this type of compounds. The alkaloid extracts were analyzed by GC/MS and the probable occurrence of individual alkaloid substances was observed. These extracts were also assayed for HuAChE and HuBuChE inhibitory activity. N. cyclamineus cv. Surfside with IC50 = 61,26 ± 6,42 µg/ml and N. cyclamineus cv. Warbeld with IC50 = 85,43 ± 11,13 µg/ml have the best results in inhibition of HuBuChE. The best inhibitory activity on HuAChE has N. cyclamineus cv. Warbeld with IC50 (HuAChE) = 36,82 ± 4,50 µg/ml. Key words: Narcissus, Acetylcholinesterase, Butyrylcholinesterase, GC/MS, Alzheimer's disease.
45

Studium biologické aktivity alkaloidů izolovaných z Fumaria officinalis L. (Fumariaceae) II. / Study of biological activity of alkaloids isolated from Fumaria officinalis L. (Fumariaceae) II.

Malý, Lukáš January 2014 (has links)
Malý, L.: Study of biological activity of alkaloids isolated from Fumaria officinalis L. (Fumariaceae) II. Diploma Thesis, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové 2014, 49 pp. Obtained diethylether extract of Fumaria officinalis L. was separated to fractions in column chromatography with petrol, chloroform and ethanol. Preparative TLC and crystalisation led to isolation of five alkaloids from fraction. Alkaloids were identified by GC-MS and NMR specters, optical rotation and melting point as protopine, cryptopine, (-)-fumaricine, (+)-fumariline and (+)-parfumidine. Isolated alkaloids were tested for their inhibition activity towards acetyl- and butyrylcholinesterase and towards prolyloligopeptidase. Activities were compared with standards. Natural inhibitor galanthamine showed IC50 AChE 1.710 ± 0.065 µM, IC50 BuChE 42.30 ± 1.30 µM. Best inhibition activity showed protopine (IC50 AChE 345.4 ± 24 µM, IC50 BuChE 239.6 ± 22.3 µM) and cryptopine (IC50 AChE 477.71 ± 47.33 µM, IC50 BuChE 270.82 ± 39.12 µM). The highest prolyloligopeptidase inhibition activity showed (+)-parfumidine with IC50 POP 99.2 µM, which was more active than used natural inhibitor baicaline (IC50 POP 605.9 ± 0.021 µM). Synthetic POP...
46

Biologická aktivita obsahových látek rostlin XXIX. Alkaloidy vybraných odrůd taxonu Narcissus triandrus L. a jejich účinek na acetylcholinesterasu a butyrylcholinesterasu / Biological activity of plant metabolites XXIX. Alkaloids from selected cultivars of Narcissus triandrus L. and their influence on acetylcholinesterase and butyrylcholinesterase

Farkašovský, Marek January 2015 (has links)
Farkašovský M.: Biological activity of plant metabolites XXIX. Alkaloids of selected cultivars of Narcissus triandrus L. and their influence on acetylcholinesterase and butyrylcholinesterase. Diploma thesis. Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of pharmaceutical botany and ecology, Hradec Králové 2015, 70 pages Screening of seven bulb samples of Narcissus genus was performed. It included cultivars Narcissus triandrus cv. Hawera, Narcissus triandrus cv. Ice Wings, Narcissus triandrus cv. Stint, Narcissus triandrus cv. Tresamble, Narcissus cyclamineus cv. February Gold, Narcissus cyclamineus cv. Greenlet and Narcissus cyclamineus cv. Itzim. Primary extract was prepared by boiling crushed bulbs in ethanol 95% and then it was condensated. After extraction in diethyl ether and ethyl acetate was pure alkaloid extract dried with air flow in water bath. Isolated alkaloid extracts were tested for their inhibition activity on acetylcholinesterase and butyrylcholinesterase. Also GC-MS analysis was provided to identify alkaloids. These alkaloids were identified with GC-MS analysis - epinorgalanthamine, galanthamine, galanthine, haemanthamine, hippeastrine, homolycorine, cherylline, incartine, lycoramine, lycoramine-acetate, lycorine, narwedine, neruscine, sanguinine...
47

Studium biologické aktivity alkaloidů izolovaných z Fumaria officinalis L. (Fumariaceae) I. / Study of biological activity of alkaloids isolated from Fumaria officinalis L. (Fumariaceae) I.

Kostelník, Jan January 2014 (has links)
Kostelník, J.: Study of biological activity of alkaloids isolated from Fumaria officinalis L. (Fumariaceae) I. Diploma thesis, Charles University in Prague,Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové 2014, 63 p. The aim of this study was to isolate alkaloids from joined fraction no. 55-67 (A2) obtained from the total alkaloid fraction of extract of Fumaria officinalis L. (Fumariaceae) plant. Using chromatography methods three alkaloids were isolated and then identified by structural analysis (GC-MS, NMR). Three alkaloids were isolated by using common chromagografic methods and then identified by structural analyses optical rotation and melting point as (-)-O- methylfumarophycine, (-)-sinactine a (-)-stylopine. Inhibitory activity of isolated alkaloids was assessed against human erythrocyte acetylcholinesterase, human butyrylcholineesterase and prolyl oligopeptidase. The results were expressed as IC50 values ((-)-stylopine: IC50 AChE and IC50 BuChE > 1000 μM, IC50 POP > 1000 mM; (-)-O-methylfumarophycine: IC50 AChE = 963.10 ± 135.98 µM, IC50 BuChE = 1771.0 ± 380.94 µM, IC50 POP - unmeasured; (-)-sinactine IC50 AChE = 632.0 ± 68.12 µM, IC50 BuChE = 8154.3 ± 981.42 µM, IC50 POP = IC50 POP = 52.9 ± 1.8 µM). None of alkaloids isolated showed...
48

Alkaloidy Narcissus 'Dutch 'Master' (Amaryllidaceae) a jejich biologická aktivita. II. / Alkaloids of Narcissus'Dutch Master ' (Amaryllidaceae) and their biological activity. II.

Dvořáková, Zdeňka January 2016 (has links)
Dvořáková Zdeňka: Alkaloids of Narcissus 'Dutch Master' (Amaryllidaceae) and their biological activity II. Diploma thesis 2016, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology. The content of this work was isolation of compounds from the selected fraction ND-6 obtained by column chromatography of Narcissus 'Dutch Master' alkaloid extract. Preparation of extract and its column chromatography was performed by Mrg. Daniela Hulcová as part of her doctoral studies. By the means preparative TLC was from fraction ND- 6 homolycorine type alkaloid (+)-O-methyllycorenine gained. Its structure was determined on the basis NMR, GC-MS analysis and optical rotation. The obtained data were compared with facts in known literature. By the isolated alkaloid was determined its cholinesterase inhibitory activity against acetylcholinesterase and butyrylcholinesterase. Its inhibitory activity was expressed as IC50 (M) and compared with known standards galanthamine, physostigmine, and Huperzine A. This alkaloid is inactive against cholinesterase (IC50 AChE > 1000 M, IC50 BChE > 1000 M). On the basis of gained results, we can evaluate this alkaloid from the point of view of cholinesterase inhibition as potentially unusable in the treatment of AD. Key...
49

Alkaloidy Narcissus 'Dutch 'Master' (Amaryllidaceae) a jejich biologická aktivita. I. / Alkaloids of Narcissus 'Dutch Master '(Amaryllidaceae) and their biological activity. I.

Vacková, Lucie January 2016 (has links)
Vacková, L.: Alkaloids Narcissus 'Dutch Master' (Amaryllidaceae) and their biological activity. I. Diploma thesis, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové 2016. From a selected fraction ND-6, which was obtained by column chromatography of an alkaloid extract of Narcissus 'Dutch Master' (preparation of the alkaloid extract and column chromatography was performed by Mgr. Daniela Hulcová within her doctoral thesis), lycorine alakloid O-acetylpluviin was isolated using preparative TLC. Its structure was determined on the basis of MS, NMR analysis, and optical rotation, the obtained data were compared with the literature. The isolated alkaloid was tested on its possibility to inhibit human acetylcholinesterase and butyrylcholinesterase. The activity was expressed as IC 50 values (IC50 AChE = 648.03 ± 53.95 μM, IC50 BChE = 602.50 ± 48.50 μM) and compared with IC50 values of galanthamine, huperzine A and physostigmine. O-acetylpluviine showed a very low inhibitory cholinesterase activity, and so, the alkaloid does not seem to be a suitable cholinesterase inhibitor for potential use in the treatment of Alzheimer's disease. Keywords: Narcissus 'Dutch Master', Amaryllidaceae, lycorine alkaloids, Alzheimer's disease,...
50

Determination of permeability and active transport of selected butyrylcholinesterase inhibitors in vitro / Determination of permeability and active transport of selected butyrylcholinesterase inhibitors in vitro

Machan, Radek January 2016 (has links)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Radek Machan Supervisor: PharmDr. Lukáš Červený, Ph.D. Title of diploma thesis: Determination of permeability and active transport of selected butyrylcholinesterase inhibitors in vitro European Medicine Agency (EMA) and Food and Drug Administration agency (FDA) emphasise drug membrane permeability and drug-drug interactions on ABC transporters expressed in physiological barriers should be investigated for compounds in preclinical studies or for those already clinically used but evidence free. In this work we aimed to assess the capability of several experimental butyrylcholinesterase inhibitors that had been designed to treat dementia to permeate blood-brain barrier and to elucidate role of ATP-binding (ABC) cassette transporters in this transport. For this purpose, we employed in vitro bidirectional transport study across monolayers formed by polarized and highly differentiated Caco-2 cells. The permeability values gained from measurements were similar to values of several commonly used drugs for treatment of CNS disorders (e.g. antidepressants, antiepileptics). In addition, the compounds showed values of efflux ratio (basolateral- to-apical/apical-to-basolateral) approximately one...

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