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,...

1 9 ABSTRACT Jurkaninová, M.: Vinca minor L. alkaloids and their biological activity I. Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany, Hradec Králové, 2019 The aim of this thesis was the isolation of alkaloids from selected fraction 3 (joined fractions (15 - 36), which was a sub-fraction of the fraction VM 323 - 327. It was obtained from the previous processing of an alkaloidal extract from the Vinca minor L at the Department of Pharmaceutical Botany as a part of elaboration of diploma thesis of Aneta Vítavcová.[78] The fraction VM 323-327 was separated by column chromatography on silica gel and a totally, of 7 subfractions were obtained. Subsequent repeated processing of the selected sub-fraction 3 (15 - 36) by preparative TLC on silica gel resulted in the isolation of (-)-vinoxine and its racemate (±)-vinoxine. Identification of their structure was determined based on MS, NMR and optical rotation. The inhibitory activity against acetylcholinesterase, butyrylcholiesterase and prolyl oligopeptidase were determined for the isolated substances. Inhibitory activity against selected enzymes was measured by spectrophotometric methods. Isolated alkaloids were required to be inactive against AChE and POP (IC50 >1000 μM), against to BChE showed a...

La flexibilité est une caractéristique intrinsèque des protéines qui doivent, dès le mo- ment de leur synthèse, passer d’un état de chaîne linéaire à un état de structure tridimen- sionnelle repliée et enzymatiquement active. Certaines protéines restent flexibles une fois repliées et subissent des changements de conformation de grande amplitude lors de leur cycle enzymatique. D’autres contiennent des segments si flexibles que leur structure ne peut être résolue par des méthodes expérimentales. Dans cette thèse, nous présentons notre application de méthodes in silico d’analyse de la flexibilité des protéines : • À l’aide des méthodes de dynamique moléculaire dirigée et d’échantillonnage pa- rapluie, nous avons caractérisé les trajectoires de liaison de l’inhibiteur Z-pro- prolinal à la protéine Prolyl oligopeptidase et identifié la trajectoire la plus pro- bable. Nos simulations ont aussi identifié un mode probable de recrutement des ligands utilisant une boucle flexible de 19 acides aminés à l’interface des deux domaines de la protéine. • En utilisant les méthodes de dynamique moléculaire traditionnelle et dirigée, nous avons examiné la stabilité de la protéine SAV1866 dans sa forme fermée insérée dans une membrane lipidique et étudié un des modes d’ouverture possibles par la séparation de ses domaines liant le nucléotide. • Nous avons adapté auproblème de la prédiction de la structure des longues boucles flexibles la méthode d’activation et de relaxation ART-nouveau précédemment uti- lisée dans l’étude du repliement et de l’agrégation de protéines. Appliqué au replie- ment de boucles de 8 à 20 acides aminés, la méthode démontre une dépendance quadratique du temps d’exécution sur la longueur des boucles, rendant possible l’étude de boucles encore plus longues. / Flexibility is an intrinsic characteristic of proteins who from the moment of synthesis into a linear chain of amino acids, have to adopt an enzymatically active tridimensionnel structure. Some proteins stay flexible once folded and display large amplitude confor- mational changes during their enzymatic cycles. Others contain parts that are so flexible that their structure can’t be resolved using experimental methods. In this thesis, we present our application of in silico methods to the study of protein flexibility. • Using steered molecular dynamics and umbrella sampling, we characterized the binding trajectories of the Z-pro-prolinal inhibiter to the Prolyl oligopeptidase pro- tein and we identified the most probable trajectory. Our simulations also found a possible ligand recrutement mechanism that involves a 19 amino acids flexible loop at the interface of the two domains of the protein. • Using traditional and steered molecular dynamics, we examined the stability of the SAV1866 protein in its closed conformation in a lipid membrane and we studied one of its proposed opening modes by separating its nucleotide binding domains. • We also adapted the activation-relaxation technique ART-nouveau which was pre- viously used to study protein folding and aggregation to the problem of structure prediction of large flexible loops. When tested on loops of 8 to 20 amino acids, the method demonstrate a quadratic execution time dependance on the loop length, which makes it possible to use the method on even larger loops.

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...

Pavuková, S.:Vinca minor L. alkaloids and their biological activity II. Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany, Hradec Králové 2020. Vinca minor L. is a species of species of flowering plant, native mainly to central and southern Europe, which containst more than 50 indole alkaloids. During screening of potential plant inhibitors against human acetylcholinesterase (hAChE) and butyrylcholinesterase (HBChE) at our department, an alkaloidal extract from dried aerial parts of Vinca minor demonstrated strong and selective hBChE inhibitory activity with an IC50 value of 13.60 ± 0.83 μg/mL, however, against hAChE was inactive (IC50 value >100 μg/mL). The fraction VM 323 - 327 (4,72 g) was separated by column chromatography on silica gel again with stepwise elution by using chloroform and ethanol and overall 7 joined fractions were obtained.Subsequently, repeated preparative TLC on silica gel led to isolation of three compounds; the newly isolated substance SP-1, (-)-picrinine (SP-2) and deacetylakuammiline (SP-3). Their structures were elucidated with mass spectrometry (ESI), NMR and optical rotation. Isolated alkaloids were tested on ability to inhibit AChE, BuChE, POP a GSK-3β, which are enzymes playing an important role in...

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The phytochemical study of the crude extract hexane, methanol and fractions (acid ether, basic ether and basic acetate) from the stem bark of E. crista-galli (Fabaceae) resulted in the isolation of four compounds: The phytosterol stigmasterol (70), the triterpene lupeol (71) and the alkaloids erysotrine (1) and epierythratidine (50), usual in the genus Erythrina. The structures of the isolated metabolites were elucidated by 1H and 13C NMR uni and bidimensional, and compared with standard sample and data available in the literature. The extracts, fractions and isolated compounds were tested for their antimicrobial and antitumor front cancer cells HT29 (colorectal) activities, as well as regarding the capacity of inhibition of enzymes prolyl oligopeptidase, dipeptidil peptidase-VI and acetylcholinesterase. The crude methanolic extract, all fractions and individual compounds showed high antimicrobial activity mainly against Gram-positive and Gram-negative bacteria. The results were satisfactory in POP inhibition assays, when the crude methanolic extract and its fractions, mainly acid ether fraction, showed great inhibitor potential against this enzyme. For DPP-IV only the crude hexane extract was active. The in vitro antitumoral activity of the crude methanolic extract, basic fractions and the isolate alkaloids was investigated at different concentrations against the human colon cancer cell line HT-29 (PicoGreen dsDNA assay). The results suggest that the anti-proliferative effect of E. crista-galli extract on HT-29 cancer cells may be attributed, at least in part, to the presence of the erythrinian alkaloids 1 and 50. / O estudo fitoquímico do extrato bruto hexânico, metanólico e frações (éter ácida, éter básica e acetato básica) das cascas do caule de E. crista-galli (Fabaceae) resultou no isolamento de quatro compostos: o fitoesterol estigmasterol (70) e o triterpeno lupeol (71) além dos alcaloides erisotrina (1) e epieritratidina (50) usuais do gênero Erythrina. As estruturas dos metabólitos isolados foram elucidadas através de RMN 1H e 13C, uni e bidimensionais, além de comparação com amostra padrão quando existente e dados disponíveis na literatura. Os extratos, as frações e os compostos isolados foram testados quanto à sua atividade antimicrobiana, antitumoral frente a células cancerígenas HT29 (colorretal) e de inibição das enzimas POP, DPP-IV e AChE. Dentre as amostras testadas, o extrato bruto metanólico (EBM), suas frações (FEA, FEB e FAB) e compostos isolados apresentaram grande potencial antimicrobiano principalmente frente as bactérias Gram-positivas e Gram-negativas. Os resultados obtidos nos ensaios enzimáticos foram satisfatórios para a enzima POP, onde o EBM e suas frações, principalmente a fração éterea ácida (FEA), demonstraram grande potencial inibidor desta enzima. Para a DPP-IV apenas o extrato bruto hexânico (EBH) mostrou-se ativo. O efeito antitumoral da planta em questão também foi investigado e os resultados obtidos indicam que o EBM, a combinação das frações FEB e FAB e o alcaloide epieritratidina (50) possuem um grande efeito antiproliferativo frente às células do colorretal (HT29) após 72 horas de exposição.