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Alkaloids of leaves of species Liriodendron tulipifera L. and their biological activity II
Matoušová, Kateřina ; Hošťálková, Anna (advisor) ; Chlebek, Jakub (referee)
7 ABSTRACT Matoušová K.: Alkaloids of leaves of species Liriodendron tulipifera L. and their biological activity II. Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmacognosy and Pharmaceutical Botany, Hradec Králové, 2023. Key words: Liriodendron tulipifera, alkaloids, biological activity. Alkaloids isolated from the leaves of Liriodendron tulipifera L. have been described to have a various biological activity. For Alzheimer's disease (AD) treatment is significant primarily the alkaloid's inhibitory activity towards enzymes acetylcholinesterase and butyrylcholinesterase, which contribute to the pathogenesis of AD. Substances affecting these enzymes represent the main accessible approach to AD treatment, therefore plant-based drug screening remains a relevant topic. An alkaloid extract from the leaves of Liriodendron tulipifera was chosen for an isolation and identification of alkaloids due to the positive results of preliminary tests on its cholinesterase inhibitory activity. The extract was separated by using a flash chromatography. The isolation of alkaloids from selected fractions (no. 81-89 and no. 68-89) was done by the use of preparative thin-layer chromatography. The structural analysis (implemented by NMR and MS) of isolated substances was determined and...
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Alkaloids of Papaver rhoeas L. (Papaveraceae) and their biological activity related to Alzheimerʼs disease VI.
Ludvik, Matěj ; Chlebek, Jakub (advisor) ; Šafratová, Marcela (referee)
Ludvik M., Papaver rhoeas L. (Papaveraceae) alkaloids and their activity related to Alzheimer disease VI., diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové 2023, number of pages 69. This diploma thesis was focused on alkaloids from combined fractions 13-15 of diethylether extract from Papaver rhoeas L. The methods used for extraction of the alcaloids include flash chromatography and preparative thin-layer chromatography. The structures of isolated compounds were determined by using mass spectrometric and spectrophotometric methods (GC-MS, NMR and optical rotation). Alkaloids were identified as galanthamine and N,N-dimethyltryptamine. Subsequently, N,N-dimethyltryptamine was tested for its biological activity against human cholinesterases, specifically acetylcholinesterase and butyrylcholinesterase. Galanthamine was not tested on ability to inhibit cholinesterase, since the compound has been already tested on this activity at the Department of Pharmacognosy and Pharmaceutical Botany. N,N-dimethyltryptamine showed mild inhibitory activity against butyrylcholinesterase (IC50 = 44,14 ± 1,76) and no activity against acetylcholinesterase (IC50 = >100). Despite its mild activity towards butyrylcholinesterase, N,N-dimethyltryptamine can't be used in therapy of Alzheimer's disease,...
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Alkaloids of Papaver rhoeas L. (Papaveraceae) and their biological activity related to Alzheimerʼs disease V.
Dušánková, Zita ; Chlebek, Jakub (advisor) ; Hošťálková, Anna (referee)
Dušánková Z.: Alkaloids of Papaver rhoeas L. (Papaveraceae) and their biological activity related to Alzheimerʼs diesease V.; Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmacognozy and Pharmaceutical Botany, Hradec Králové 2023, pages 72. The aim of this diploma thesis was focused on isolation of alkaloids from a combined fraction 7-8 of an alkaloidal diethyl ether (Et2O) extract of aerial parts of Papaver rhoeas L. (Papaveraceae). Column chromatography (flash chromatography), planar chromatography (preparative TLC) and crystallization were used for the isolation of alkaloids. The structures of isolated substances were elucidated using NMR, GC-MS methods and optical rotation. Isolated alkaloids were identified as ZD-1, (+)-3,4-dehydrotheaspirone, (±)-juziphine, (+)-lirinidine and protopine. Alkaloids were tested for biological activity against enzymes (acetylcholinesterase, butyrylcolinesterase and prolyl oligopeptidase). (+)-3,4-Dehydrotheaspirone, (±)-juziphine, and protopine did not show significant inhibitory activities against cholinesterases (IC50 values >100 µM). Protopine was also inactive against prolyl oligopeptidase (IC50 >1000 µM ). (+)-Lirinidine showed a moderate inhibitory activity against BuChE (IC50 value of 23,45 ± 0,55 µM), towards...
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Screening of biological activity of various species of the genus Narcissus sp. III
Růžičková, Zuzana ; Suchánková, Daniela (advisor) ; Chlebek, Jakub (referee)
CharlesUniversity,FacultyofPharmacyinHradecKrálové Department: DepartmentofPharmacognosyandPharmaceuticalbotany Author: Zuzana Růžičková Supervisor: PharmDr.DanielaSuchánková,Ph.D. Title of thesis: Screeningofbiologicalactivityofvariousspeciesofthe genusNarcissussp.III Key words: Narcissus sp., bulbs, alkaloidal extracts, GC/MS analysis, biological activity, acetylcholinesterase,butyrylcholinesterase Alzheimer'sdiseaseisaseverediseasethatrepresentsthemostcommoncauseofdementiaanddeath. Thedisease ischaracterized bya decrease off nerve cells and brain tissue.Forpatientswith Alzheimer's disease, memory lapses are typical, at the beginning of the disease states of anxiety and depression occur.The main cause isthe formation and deposition of β-amyloid and deficit of the neurotransmitter acetylcholine. Unfortunately, we do not know how to cure the Alzheimer's disease, but we can significantly slow it down by prolonging themild stages of the disease. Treatment is mainly directed to AChEinhibitorstoeliminateACHdeficiency. The main goal of this diploma thesis was to obtain summary alkaloid extracts from bulbs of seven cultivars of the genus Narcissus sp., which could have been a potential source of substances for the treatment of Alzheimer's disease. Cultivars were specifically Narcissus cv. Banana Splash,...
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Alkaloid isolation from Vinca minor and their biological activity II.
Míšek, Vít ; Hošťálková, Anna (advisor) ; Chlebek, Jakub (referee)
Míšek, V.: Alkaloid isolation from Vinca minor and their biological activity II. Diploma thesis, Faculty of Pharmacy in Hradec Králové, Charles University, Department of Pharmacognosy and Pharmaceutical Botany, Hradec Králové, 2023 Supervisor: PharmDr. Anna Hošťálková, Ph.D. Key words: secondary metabolites, Apocynaceae, Vinca minor, cholinesterases, cytotoxicity, alkaloids, isolation, biological activity Alzheimer's disease (AD) is a neurodegenerative disease characterized by the progressive development of cognitive dysfunction, impact on normal daily functions and neuropsychiatric symptoms. There is a limited number of compounds for pharmacotherapy AD, moreover, AD cannot be treated causally. Therefore, research focused on the discovery of new active substances, including natural origin ones, could be one of the possible options for widening the pool of substances used in AD treatment. An extract was prepared by extracting the aerial parts of Vinca minor L. with ethanol and subsequent liquid-luquid extractin at different pH. Using column and preparative thin layer chromatography, this extract was further processed to isolate individual alkaloids. The structure of isolated alkaloids was determined by spectrometric methods (GC/MS and NMR). After comparing the obtained structures with the literature...
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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.
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Vinca minor L. alkaloids and their biological activity III.
Valová, Dominika ; Chlebek, Jakub (advisor) ; Hradiská 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...
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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...
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Screening of selected alkaloids of Fumariaceae and Amaryllidaceae families on Farnesoid X receptor and the G protein-coupled bile acid receptor 1
Hutníková, Miriama ; Pávek, Petr (advisor) ; Chlebek, Jakub (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Miriama Hutníková Supervisor: Prof. PharmDr. Petr Pávek, PhD. Title of diploma thesis: Screening of selected alkaloids of Fumariaceae and Amaryllidaceae families on the farnesoid X receptor and the G protein coupled receptor 1 Farnesoid X receptor (FXR) and bile acid receptor associated with G protein 1 (TGR5) significantly affect metabolic processes in the human body. The role of FXR in neuronal apoptosis in Alzheimer's disease (AD) has also been discovered. The possible structural similarity of the small lipophilic molecules binding to these receptors and the alkaloids found in the plants Corydalis cava and Narcissus pseudonarcissus, as well as the richoften use of these plants in traditional medicine, represent a potential therapeutic intervention for these molecules. In our screening methods, we performed tests using a luciferase gene reporter assay to determine the ability of the alkaloids to interact with FXR and TGR5 in the HepG2 cell line. Many derivatives have shown a strong ability to antagonize FXR and TGR5 activated by obethicholic (OCA) or litocholic (LCA) acids in this assay. Some of the compounds also demonstrated the ability to potentiate the effects of OCA or LCA. Cytotoxicity...
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Biological activity of Peganum harmala L. alkaloids and their semi-synthetic derivatives II.
Fejtková, Martina ; Chlebek, Jakub (advisor) ; Cahlíková, Lucie (referee)
Fejtková Martina: Biological activity of Peganum harmala L. alkaloids and their semi-synthetic derivatives II. Diploma thesis 2022. Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmacognosy und Pharmaceutical botany. This diploma thesis deals with the preparation of semi-synthetic derivatives of the alkaloid harmine and the study of their biological activity. The alkaloid harmine was isolated by preparative TLC from an alkaloid extract, exactly from its subfraction PH-F1. Semi-synthetic derivatives were prepared by incorporation of different substituents in the N9 position of harmine. For the purposes of this diploma thesis were prepared 17 derivatives, which were subsequently identified on the basis of LC-MS, ESI-HRMS and NMR analysis. After structural elucidation of prepared derivatives, their biological activity was studied. The prepared substances were tested for their inhibitory effect on human acetylcholinesterase (AChE), human butyrylcholinesterase (BuChE), glykogen synthase kinase 3β (GSK-3β) and their cytotoxic activity was also measured on selected tumor and leukemia lines and one healthy cell line. Some of the prepared derivatives showed interesting selective inhibitory potencial against human BuChE, the most active derivative was...
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