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Alkaloids of the family Amaryllidaceae and their biological aktivity I.
Puskásová, Dominika ; Šafratová, Marcela (advisor) ; Chlebek, Jakub (referee)
Puskásová Dominika: Alkaloids of the Amaryllidaceae family and their biological activity I. Diploma thesis 2019. Charles university in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmacognosy. The aim of this thesis was to isolate alkaloids from herbal extract, which was obtained from Narcissus pseudonarcissus 'Dutch Master' plant. The preparation and column chromatography of the extract were performed by PharmDr. Daniela Hulcová, Ph.D. as a part of her doctoral study. Using the preparative TLC method, 2 alkaloids marked as No.2.1 and 2.2.2 were isolated from the fraction No.4. Their structure was determined by using the NMR, GC-MS analysis and optical rotation. After comparing the data obtained with literature, the compounds were identified as (+)-homolycorine and (+)-masonine. Both homolycorine and masonine were subsequently subject to testing of inhibitory activity against acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), prolyloligopeptidase (POP) and glycogensynthase kinase 3β (GSK-3β). The activity was expressed as IC50 and was compared to IC50 of the reference substances. Galanthamine (IC50 AChE = 1,7 ± 0,1 μM, IC50 BuChE = 42,3 ± 1,3 μM) and huperzine A (IC50 AChE = 0,033 ± 0,001 μM, IC50 BuChE > 500 μM) were used as standards to compare the inhibitory activity...
Vinca minor L. alkaloids and their biological activity I.
Jurkaninová, Martina ; Chlebek, Jakub (advisor) ; Opletal, Lubomír (referee)
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...
Biological aktivity of secondary plants metabolites X. Alkaloids of Vinca minor L.
Šípková, Pavla ; Hošťálková, Anna (advisor) ; Chlebek, Jakub (referee)
Šípková, P.: Biological activity of secondary plants metabolites X. Alkaloids of Vinca minor L. Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany, Hradec Králové, 2019, 66 s. Key words: Apocynaceae, Vinca minor, alkaloids, isolation, biological activity, screening Alzheimer's disease is a progressive neurodegenerative disease. The number of affected patients is constantly increasing. This disease cannot be treated casually, therefore discovering and testing new substances that could potentially be used in a treatment is very important. The Vinca minor L. fraction after column chromatography was separated by flash chromatography. Isolation of the individual alkaloids was performed by preparative TLC. Based on NMR and MS analyses and comparison with literature, alkaloids were identified as vincarubine and (-)-vinoxine. Modified Ellman's method was used to test cholinesterase inhibitory activity of isolated alkaloids. Acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) are enzymes, that play a very important role in the pathofysiology of Alzheimer's diasease. (-)-Vinoxine showed relatively high activity against BuChE (IC50 = 24,61 ± 1,71 µM), inhibitory activity against AChE was insignificant (IC50 > 1000µM). Vincarubin did not...
Cytotoxic and cholinesterase inhibitory activity of extracts from selected species of the Centaurea L. genus
Faschingbauer, Jakub ; Chlebek, Jakub (advisor) ; Šafratová, Marcela (referee)
Faschingbauer J.: Cytotoxic and cholinesterase inhibitory activity of extracts from selected species of the Centaurea L. genus. Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany, Hradec Králové, 2019. During the screening of biologically active secondary metabolites of plants carried out at the Department of Pharmaceutical Botany FAF UK, selected taxa of the genus Centaurea (Asteraceae) were investigated. This study is focused on a basic phytohemical research of extracts prepared from Centaurea cyanus, Centaurea jacea, Centaurea scabiosa, Centaurea pseudophrygia, Centuarea stoebe, Centaurea solstitialis a Centaurea benedicta. Extracts were prepared for evidence of the proof reactions of TLC and MS analysis (EI, ESI) to clarify a potential presence of alkaloids. EtOAc and ethanol extracts were evaluated for potential inhibitory activity against human erythrocyte acetylcholinesterase (AChE) and plasma butyrylcholinesterase (BChE) and cytotoxicity against selected 9 tumor lines. C. cyanus alkaloid extract had interesting cholinesterase activity which selectively inhibited BChE (IC50 BChE = 22.62 ± 3.62 μg / ml, IC50 AChE = 221.50 ± 44.56 g / ml). Other EtOAc extracts of selected Centaurea species were considered inactive (IC50 > 100 μg/ml)....
Alkaloids from the wood of the species Liriodendron tulipifera L. and their activity against human cholinesterases
Hrušková, Magda ; Hošťálková, Anna (advisor) ; Chlebek, Jakub (referee)
Hrušková M.: Alkaloids from the wood of the species Liriodendron tulipifera L. and their activity against human cholinesterase. Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany, Hradec Králové, 2018. Key words: Liriodendron tulipifera, alkaloids, biological activity. The alkaloids from the wood of the species Liriodendron tulipifera L. were isolated and their inhibitory activity against acetylcholinesterase, butyrylcholinesterase and propyl oligopeptidase, which are enzymes involved in the pathophysiology of Alzheimer's disease (AD), was investigated. The search and testing of new substances, which are used in AD treatment, is very relevant, as this disease cannot be casually treated yet. An alkaloid extract of Liriodendron tulipifera L. wood was tested in a preliminary testing for inhibitory activity against human cholinesterase. Because of the promising results, it was chosen for an isolation and identification of possible effective alkaloids. The extract was carried out by column chromatography with a step gradient elution. A preparative TLC was used to isolate alkaloids. The identification of alkaloids was done by structural analyses (NMR and MS). Optically active substances were measured for their optical rotation. A modified...
Alkaloids of the family Amaryllidaceae and their biological aktivity I.
Puskásová, Dominika ; Šafratová, Marcela (advisor) ; Chlebek, Jakub (referee)
Puskásová Dominika: Alkaloids of the Amaryllidaceae family and their biological activity I. Diploma thesis 2019. Charles university in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmacognosy. The aim of this thesis was to isolate alkaloids from herbal extract, which was obtained from Narcissus pseudonarcissus 'Dutch Master' plant. The preparation and column chromatography of the extract were performed by PharmDr. Daniela Hulcová, Ph.D. as a part of her doctoral study. Using the preparative TLC method, 2 alkaloids marked as No.2.1 and 2.2.2 were isolated from the fraction No.4. Their structure was determined by using the NMR, GC-MS analysis and optical rotation. After comparing the data obtained with literature, the compounds were identified as (+)-homolycorine and (+)-masonine. Both homolycorine and masonine were subsequently subject to testing of inhibitory activity against acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), prolyloligopeptidase (POP) and glycogensynthase kinase 3β (GSK-3β). The activity was expressed as IC50 and was compared to IC50 of the reference substances. Galanthamine (IC50 AChE = 1,7 ± 0,1 μM, IC50 BuChE = 42,3 ± 1,3 μM) and huperzine A (IC50 AChE = 0,033 ± 0,001 μM, IC50 BuChE > 500 μM) were used as standards to compare the inhibitory activity...
Alkaloids of Vinca minor (Apocynaceae) and their biological activities
Klátilová, Anežka ; Cahlíková, Lucie (advisor) ; Chlebek, Jakub (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical botany Candidate: Anežka Klátilová Supervisor: doc. Ing. Lucie Cahlíková Ph. D. Title of diploma thesis: Alcaloids of Vinca minor (Apocynaceae) and their biological activities The aim of this diploma thesis was to process the assigned fraction isolated from the Vinca minor L. plant and to isolate at least one alkaloid to test its biological activity. Using preparative TLC, the alkaloid was sequentially isolated from the fraction, which was then subjected to a structural analysis. NMR and EI-MS methods were used herein. Thanks to these analyzes, the alkaloid was identified as venoterpine. Furthermore, the alkaloid was prepared to test for biological activity. Thus, the isolated alkaloid was identified as venoterpine and tested for biological activity. The observed inhibitory concentration (IC50) to HuAChE and HuBuChe was more than 500 μM, indicating that venoterpine does not rank as a significant inhibitor of cholinesterase. Likewise, the value of cytotoxic activity, when this activity was found to be greater than 10 μM to colorectal cancer cells as well as to healthy cells, is not significant. Key words: Vinca minor, Apocynaceae, alkaloids, biological activities
Alkaloids from wood of the species Liriodendron tulipifera L. and their biological activity
Klíčová, Anna ; Hošťálková, Anna (advisor) ; Chlebek, Jakub (referee)
Klíčová A.: Alkaloids from wood of the species Liriodendron tulipifera L. and their biological activity. Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department: Pharmaceutical Botany, Hradec Králové, 2018. Supervisor: PharmDr. Anna Hošťálková, Ph.D. Key words: Liriodendron tulipifera, secondary metabolites, alkaloids, biological activity Alzheimer's disease (AD) is the most common type of dementia. It is neurodegenerative disorder. Patients suffer from cognitive disorder in combination with aphasia, apraxia or disorders of executive functions, which leads to exacerbation of working or social skills. Nowadays, there exist no casual treatment for AD, and that is why the intense research is still waging. Currently there are available remedies, which can slow down progress of AD. These drugs includes also natural substances. An alkaloid extract of Liriodendron tulipifera L. wood showed promising inhibition of human cholinesterases in a preliminary testing. These results were the reason why this extract has been chosen for further isolation of single alkaloids and identification of their biological activity. Isolation was made by column chromatography with step gradient elution. Then was used preparative TLC to isolate single alkaloids. Identification of alkaloids was...
Purification of phlorizin from Malus domestica Borkh. leaves by solid-phase extraction and semi-preparative high performance liquid chromatography.
Prachařová, Eva ; Chlebek, Jakub (advisor) ; Chocholouš, Petr (referee)
DIPLOMA THESIS Purification of phlorizin from Malus domestica Borkh.by solid-phase extraction and semi-preparative high-performance liquid chromatography Eva Prachařová Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Botany The aim of this diploma thesis was to find the best conditions for purification of a flavonoid extract from leaves of Malus domestica Borkh., and obtaining the purest fraction of phlorizin. Phlorizin may be used in the treatment of diabetes mellitus type 2 in the future, it has the ability to reduce glycemia by reducing the absorption of glucose in the small intestine and by increasing urinary glucose excretion. The first step was to find an SPE cartridge with a suitable sorbent and a suitable eluent for solid phase extraction. The DPA-6S cartridge and 100% methanol as an eluentwerefound to be the most suitable for SPE. The next step was to find the best possible conditions for semi-preparative HPLC using an ACE 5 C18 column (5 μm, C18, 150 x 10 mm i.d., 150 mm length). The mobile phase consisted of 1% (v/v) acetic acid in water (solvent A) and ethanol 100% (v/v) (solvent B), and a linear gradient elution was used (10-100% B), 0-60 min, the flow: 1mL/min. This method resulted in the 91.05% purity of phlorizin. Keywords: phlorizin, SPE,...
Alkaloids from the wood of the species Liriodendron tulipifera L. and their activity against human cholinesterases
Hrušková, Magda ; Hošťálková, Anna (advisor) ; Chlebek, Jakub (referee)
Hrušková M.: Alkaloids from the wood of the species Liriodendron tulipifera L. and their activity against human cholinesterase. Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany, Hradec Králové, 2018. Key words: Liriodendron tulipifera, alkaloids, biological activity. The alkaloids from the wood of the species Liriodendron tulipifera L. were isolated and their inhibitory activity against acetylcholinesterase, butyrylcholinesterase and propyl oligopeptidase, which are enzymes involved in the pathophysiology of Alzheimer's disease (AD), was investigated. The search and testing of new substances, which are used in AD treatment, is very relevant, as this disease cannot be casually treated yet. An alkaloid extract of Liriodendron tulipifera L. wood was tested in a preliminary testing for inhibitory activity against human cholinesterase. Because of the promising results, it was chosen for an isolation and identification of possible effective alkaloids. The extract was carried out by column chromatography with a step gradient elution. A preparative TLC was used to isolate alkaloids. The identification of alkaloids was done by structural analyses (NMR and MS). Optically active substances were measured for their optical rotation. A modified...

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