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Alkaloids of Narcissus'Dutch Master ' (Amaryllidaceae) and their biological activity. II.
Dvořáková, Zdeňka ; Chlebek, Jakub (advisor) ; Ločárek, Miroslav (referee)
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...
Study of biological activity of alkaloids isolated from Fumaria officinalis L. (Fumariaceae) II.
Malý, Lukáš ; Chlebek, Jakub (advisor) ; Opletal, Lubomír (referee)
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...
Study of biological activity of alkaloids isolated from Fumaria officinalis L. (Fumariaceae) II.
Malý, Lukáš ; Chlebek, Jakub (advisor) ; Opletal, Lubomír (referee)
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...
Vinca minor L. alkaloids and their biological activity (inhibition of human cholinesterases) V.
Vašíčková, Alžběta ; Chlebek, Jakub (advisor) ; Hošťálková, Anna (referee)
Vašíčková A.: Alkaloids of Vinca minor L. and their biological activity (inhibition of human cholinesterases) V. Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany, Hradec Králové 2020. From the selected fraction VM 215-258 were isolated 3 alkaloids by flash chromatography followed, preparative thin layer chromatography and crystallization. Their structure was determined by mass spectroscopy, NMR and optical rotation, and the obtained data were compared with those in literature. Strictamine and minovincinine belong to alkaloids previously isolated, the alkaloid AV-3 has not been isolated yet. These alkaloids were tested for their ability to inhibit human cholinesterases and their inhibitory activity was compared to standards galanthamine and physostigmine. Compound AV-3 showed mild inhibitory activity against BChE (IC50 μM > 86.3 ± 2.3), other alkaloids were considered inactive, their IC50 values against cholinesterases were > 100 μM. Key words: Vinca minor L. (Apocynaceae), vinca alkaloids, minovincinine, strictamine, Alzheimer's disease, acetylcholinesterase, butyrylcholinesterase.
Vinca minor L. alkaloids and their biological activity III.
Valová, Dominika ; Chlebek, Jakub (advisor) ; Breiterová, Kateřina (referee)
Valová D.: Vinca minor L. alkaloids and their biological activity III. Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany, Hradec Králové, 2020, 75 p. Alzheimer's disease (AD) is a progressive, neurodegenerative disorder and it's the most common form of dementia. Because we're still not able to treat the cause of disease, searching for a new substance is relevant. This thesis is focused on isolation of alkaloids from a Vinca minor L. alkaloidal extract as a potential drug. The preparation and column chromatography of the summary extract were performed by Ing. Miroslav Ločárek as a part of his doctoral studies. Subsequent preparative TLC led to the isolation of three compounds. The chemical structures of the isolated alkaloids were elucidated by means of optical rotation, NMR and MS analyses and by comparison of the obtained data with those in the literature. One of the compounds was determined as(-)-vincine, other two compounds have not been isolated yet. Isolated compounds were also tested for their biological activity. Vincine, DV-1 a DV-3 were tested for their ability to inhibit acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). Additionally, vincine and DV-3 were also tested for their inhibitory activity on prolyl...
Alkaloids of Papaver rhoeas L. (Papaveraceae) and their biological activity related to Alzheimerʼs disease II.
Čakurdová, Marta ; Chlebek, Jakub (advisor) ; Hošťálková, Anna (referee)
Čakurdová, M.: Alkaloids of Papaver rhoeas L. (Papaveraceae) and their biological activity related to Alzheimer's disease II. Diploma thesis, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové, 2017. The aim of this work was focused on isolation of alkaloids from the fraction 1 (joined fractions 20-27), which was obtained from the summary alkaloid extract of Papaver rhoeas L. (Papaveraceae). The alkaloids were identified by structural analysis NMR, GC-MS, optical activity and melting point. Two alkaloids were identified as (-)-stylopine and (+)-rhoeadine. Isolated substances were tested on ability to inhibit the enzymes acetylcholinesterase, butyrylcholinesterase and prolyloligopeptidase. Obtained data were expressed as IC50 values: (-)-stylopine (IC50 AChE = 522 ± 67 µM, IC50 BuChE = >1000 µM, IC50 POP = >790 µM); (+)-rhoeadine (IC50 AChE = 915 ± 64 µM, IC50 BuChE = >1000 µM, IC50 POP = >790 µM). None of the isolated substances showed so potent cholinesterase inhibitory activity as the alkaloids galanthamine (IC50 AChE = 1.71± 0.065 µM, IC50 BuChE =42.30 ± 1.30 µM) and huperzine A (IC50 AChE = 0.033 ± 0.001 µM, IC50 BuChE = >1000 µM) or rivastigmine (IC50 AChE = 0.037 ± 0.001 µM, IC50 BuChE = 3.3 ± 0.3 nM)....
Study of biological activity of isolated alkaloids from Argemone grandiflora (Papaveraceae)II.
Michal, Vojtěch ; Chlebek, Jakub (advisor) ; Ločárek, Miroslav (referee)
Michal, Vojtěch: STUDY OF BIOLOGICAL ACTIVITY OF ISOLATED ALKALOIDS FROM ARGEMONE GRANDIFLORA (PAPAVERACEAE) II. Diploma thesis 2015. Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology. Supervisor: PharmDr. Jakub Chlebek, PhD. Key words: Argemone grandiflora Sweet, Papaveraceae, alkaloids, isolation, acetylcholinesterase, butyrylcholinesterase, prolyloligopeptidase, Alzheimerʼs disease, in vitro assay. Diethylether alkaloid extract obtained from stem and roots of Argemone grandiflora Sweet was chromatografically analyzed. Using common chromatografic methods, three alkaloids were isolated in clean form. These substances were identified as allocryptopine, (-)-munitagine and (-)-norargemonine by structural analysis (MS, NMR). These obtained alkaloids were tested for their inhibitory activity against human erythrocyte acetylcholinesterase (AChE) and human plasma butyrylcholinestrase (BuChE) by Ellman's method. The results were represented as IC50 values (allocryptopine: IC50 AChE = 250,0 ± 2,52 μM, IC50 BuChE = 530 ± 28,2 μM; (-)-munitagine: IC50 AChE = 62,29 ± 5,81 μM, IC50 BuChE = 837,4 ± 23,03 μM; (-)-norargemonine: IC50 AChE = 205,17 ± 11,6 μM, IC50 BuChE = 4158,20 ± 495,78 μM). Inhibition against prolyloligopeptidase was tested for...
Alkaloids of Papaver rhoeas L. (Papaveraceae) and their biological activity related to Alzheimerʼs disease I.
Bulvová, Leontina ; Chlebek, Jakub (advisor) ; Opletal, Lubomír (referee)
Bulvová, L.: Alkaloids of Papaver rhoeas L. (Papaveraceae) and their biological activity related to Alzheimerʼs disease I. Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové 2017. The aim of this study was to process the summary alkaloidal extract of aerial parts of Papaver rhoeas L.; to isolate contained alkaloids using chromatographical methods; to identify them and to determine their inhibitory activity towards human enzymes acetylcholinesterase, butyrylcholinesterase and prolyloligopeptidase. Two alkaloids (+)-rhoeagenine and LB-2 were isolated, and the structure of LB-2 (its absolute configuration) is being determined nowadays. In vitro biological assays of these alkaloids found the following results: (+)-rhoeagenine (IC50 AChE ˃ 1000 μM, IC50 BuChE = 230 ± 10 μM, IC50 POP = 878 ± 45 μM) and LB-2 (IC50 AChE ˃ 1000 μM, IC50 BuChE = 314 ± 13 μM, IC50 POP = 706 ± 2 μM). The determined IC50 values of isolated alkaloids were compared with inhibitory standards of cholinesterases galanthamine (IC50 AChE = 1,71 ± 0,065 μM, IC50 BuChE = 42,30 ± 1,30 μM), huperzine A (IC50 AChE = 0,033 ± 0,001 μM, IC50 BuChE > 1000 μM, IC50 POP > 1000 μM) and rivastigmine (IC50 AChE = 0,037 ± 0,001 μM, IC50 BuChE = 0,0033 ± 0,0003...
Alkaloids of Narcissus 'Dutch Master' (Amaryllidaceae) and their biological activity III.
Rýdlová, Kateřina ; Chlebek, Jakub (advisor) ; Cahlíková, Lucie (referee)
Rýdlová Kateřina: Alkaloids Narcissus 'Dutch Master' (Amaryllidaceae) and their biological activity III. Diploma thesis 2017. Charles university in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology. The aim of this work was isolation of compounds from the selected fraction ND 3 - 5 obtained by column chromatography of a Narcissus 'Dutch Master' alkaloid extract. Preparation of the extract and its column chromatography was performed by Mgr. Daniela Hulcová as a part of her doctoral study. Two substances NDM-1 and NDM-2 were isolated from fraction ND 3 - 5 by column chromatography and preparative TLC. The structures were determined as (+)-masonine and (+)-homolycorine on the basis of NMR, GC-MS analysis, optical rotation and their comparison with literature data. Isolated alkaloids were tested on inhibitory activity against human erythrocyte acetylcholinesterase, plasma butyrylcholinesterase and prolyloligopeptidase. Activity of alkaloids was expressed as IC50 values: (+)-masonine (IC50 AChE = 305 ± 34 μM, IC50 BuChE = 229 ± 24 μM, IC50 POP = 314 ± 34 μM), (+)-homolycorine (IC50 AChE = 63.7 ± 4.3 μM, IC50 BuChE = 151 ± 20 μM, IC50 POP = 173 ± 41 μM). In comparison with standards of galanthamine (IC50 AChE = 1.710 ± 0.1 μM, IC50 BuChE = 42.3 ± 1.3 μM),...
Alkaloids of Papaver rhoeas L. (Papaveraceae) and their biological activity related to Alzheimerʼs disease II.
Čakurdová, Marta ; Chlebek, Jakub (advisor) ; Hošťálková, Anna (referee)
Čakurdová, M.: Alkaloids of Papaver rhoeas L. (Papaveraceae) and their biological activity related to Alzheimer's disease II. Diploma thesis, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové, 2017. The aim of this work was focused on isolation of alkaloids from the fraction 1 (joined fractions 20-27), which was obtained from the summary alkaloid extract of Papaver rhoeas L. (Papaveraceae). The alkaloids were identified by structural analysis NMR, GC-MS, optical activity and melting point. Two alkaloids were identified as (-)-stylopine and (+)-rhoeadine. Isolated substances were tested on ability to inhibit the enzymes acetylcholinesterase, butyrylcholinesterase and prolyloligopeptidase. Obtained data were expressed as IC50 values: (-)-stylopine (IC50 AChE = 522 ± 67 µM, IC50 BuChE = >1000 µM, IC50 POP = >790 µM); (+)-rhoeadine (IC50 AChE = 915 ± 64 µM, IC50 BuChE = >1000 µM, IC50 POP = >790 µM). None of the isolated substances showed so potent cholinesterase inhibitory activity as the alkaloids galanthamine (IC50 AChE = 1.71± 0.065 µM, IC50 BuChE =42.30 ± 1.30 µM) and huperzine A (IC50 AChE = 0.033 ± 0.001 µM, IC50 BuChE = >1000 µM) or rivastigmine (IC50 AChE = 0.037 ± 0.001 µM, IC50 BuChE = 3.3 ± 0.3 nM)....

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