National Repository of Grey Literature 38 records found  1 - 10nextend  jump to record: Search took 0.01 seconds. 
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...
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...
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...
Screening of biological activity of various species of the genus Kalanchoe
Mai, Thanh Tam ; Šafratová, Marcela (advisor) ; Hošťálková, Anna (referee)
Mai T. T.: Screening of biological activity of various species of the genus Kalanchoe, Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmacognosy and Pharmaceutical botany, Hradec Králové 2023. The content of this diploma thesis was the screening of the biological activity of dried flowers, stems and roots of four species from plants of the genus Kalanchoe: Kalanchoe delagoensis Eckl. & Zeyh., Kalanchoe fedschenkoi Raym.-Hamet & H.Perrier, Kalanchoe blossfeldiana Poelln. and Kalanchoe manginii 'Wendy' Raym.-Hamet & H.Perrier. By boiling the dried parts of the plants with ethanol, the summary ethanolic extracts were obtained, which were subjected to control TLC to detect the presence of alkaloids using Dragendorff's reagent. The presence of alkaloids was confirmed in the species Kalanchoe blossfeldiana Poelln, Kalanchoe manginii 'Wendy' Raym.-Hamet & H.Perrier and Kalanchoe delagoensis Eckl. & Zeyh. Furthermore, they were subjected to evidence reactions to identify the substances contained on TLC. In comparison with the literature, the presence of flavonoids, steroids substances, coumarins, triterpenes and alkaloids was confirmed in most plant extracts. Plants extracts of Kalanchoe blossfeldiana Poelln (AL-756 - extract from flowers and stems) and...
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...
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...
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.
Pyrazine derivatives as potential drugs III
Hošťálková, Anna ; Doležal, Martin (advisor) ; Kopecký, Kamil (referee)
Deriváty pyrazinu jako potanciální léčiva III. Tuberkulóza je problém v celosvětovém měřítku. Rostoucí počet nakažených lidí, vznik lékově rezistentních kmenů Mycobacterium tuberculosis a ko-infekce HIV vedly k naléhavé potřebě nových antituberkulotik. Tato diplomová práce referuje o současných léčivech používaných při léčbě tuberkulózy a některých nových potenciálních antituberkuloticích. Také bylo v rámci diplomové práce syntetizováno deset nových látek, derivátů anilidů kyseliny pyrazin-2-karboxylové, které byly charakterizovány jejich fyzikálními vlastnostmi a poté byla zkoušena jejich antimykobakteriální a antifungální aktivita in vitro. Abstract Pyrazine derivatives as potential drugs III. Tuberculosis is a health problem worldwide. The increasing number of infected people, emergence of drug resistant strains Mycobacterium tuberculosis and HIV co-infection have resulted in the urgent need for new antituberculosis drugs. This degree work reviews drugs used in current treatment for tuberculosis and some of new potential anti-tuberculosis drug candidates. Within the task of this work were also synthesized ten new compounds, derivatives of anilides of pyrazin-2-carboxylic acid, which were characterized by physical properties and then was assayed their antimycobacterial and antifungal activity in...
Isolation of alkaloids of the species Magnolia soulangeana Soul.-​Bod. and study of their biological activity
Baková, Izabela ; Hošťálková, Anna (advisor) ; Opletal, Lubomír (referee)
Baková I.: Isolation of alkaloids of the species Magnolia soulangeana Soul.-Bod. and study of their biological activity. Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové, 2017. Key words: Magnolia solulangeana, secondary metabolites, alkaloids, biological activity. Secondary metabolites of plants are responsible for various biological activities. Alkaloids were described as a potentially suitable for Alzheimer's disease therapy (AD) through their inhibition activities against cholinesterases. Nowadays, these substances are important medicine for AD, therefore a screening of herbal drugs is still a current topic. An alkaloid extract of Magnolia × soulangeana flowers was tested in a preliminary testing on anticholinesterase activity. Because of the promising results, it was chosen for an isolation and identification possible effective alkaloids. The extract was separated by a column chromatography using aluminium oxide and a step gradient elution. Alkaloids were isolated by a repeated preparative thin-layer chromatography. Individual alkaloids were identified by a structural analysis (NMR, MS) and then their optical activity was measured. Substances were tested for an inhibition activity against human...
Biological activity of plant metabolites XXXIV. Alkaloids from the herb of Glaucium flavum CRANTZ and their impact on human cholinesterases
Puzyrevská, Jana ; Hošťálková, Anna (advisor) ; Cahlíková, Lucie (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Botany and Ecology Candidate: Jana Puzyrevská Supervisor: PharmDr. Anna Hošťálková, Ph.D. Title of Thesis: Biological activity of plant metabolites XXXIV. Alkaloids from the herb of Glaucium flavum CRANTZ and their impact on human cholinesterases. Key words: Glaucium flavum Crantz, cataline, N-methyllaurotetanine, norchelidonine, protopine, AChE, BuChE. Alzheimer's disease, the most widespread neurodegenerative disease, causes decrease of cognitive functions and dementia. The most effective therapeutic approach is the application of central cholinesterase inhibitors, which alleviate cholinergic deficit in brain and thus improve memory. Currently, intensive investigation of new active compounds including natural substances is carried on. Within the preliminary testing, alkaloid extract from Glaucium flavum Crantz herb showed promising inhibition of human cholinesterases, so it was selected for further examination. The primary alkaloid extract was acquired from dried flowering herb by extraction with ethanol and subsequent liquid extraction at different pH. This extract was treated by preparative thin layer chromatography. The structure of alkaloids was determined by spectrometric methods (MS, NMR) and their optical...

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