National Repository of Grey Literature 36 records found  beginprevious22 - 31next  jump to record: Search took 0.00 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...
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 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)....
Alkaloids of family Amaryllidaceae: genus Zephyranthes
Jánská, Lucie ; Šafratová, Marcela (advisor) ; Hošťálková, Anna (referee)
Author: Lucie Jánská Název: Alkaloids of family Amaryllidaceae: genus Zephyranthes Diploma thesis Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmacognosy 2018, 75 p. The aim of this diploma thesis was to summarize all knowledge about alkaloids izolated from Zephyranthes plants of Amaryllidaceae family. It contains a detail overview of botanical charactericts of phytochemically studied plants of the genus Zephyranthes. Also the overview of alkaloids with bilogical activity was described. Within the genus Zephyranthes 10 species were studied phytochemically and 89 alkaloids were isolated from this plants. This alkaloids are divided in several structural groups. The lycorine-, haemanthamine-, galanthamine- and pancratistatine-type alkaloids occure the most frequently. Acetylcholinesterase-inhibitory, anticancer and antimalarial activity of the alkaloids was described like the most important. The most significant acetylcholinesterase- inhibitory activity was observed in alkaloids from galanthamine sctructural type. Anticancer activity was found the most in lycorine-, pancratistatine- and haemanthamine- type alkaloids. The most notable antimalarial activity was observed in lycorine- and heamanthamine- type alkaloids. Keywords Zephyranthes, Amaryllidaceae,...
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...
Alkaloids of Amaryllidaceae family: isolation, structural identification, biological activity. I
Burkertová, Alice ; Cahlíková, Lucie (advisor) ; Hošťálková, Anna (referee)
Dohnalova A: Alkaloids of Amaryllidaceae family: isolation, structural identification, biological activity. I; Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové, 2017, 64 p. The Amaryllidaceae family includes bulbous, beautifully flowering plants that have been used for thousands of years in traditional medicine. The major chemical compounds found in this particular plant family are alkaloids, namely Amaryllidaceae alkaloids. Until now, more than 500 isoquinoline alkaloids have been discovered, which exhibit a diverse biological activity including antitumor and antibacterial. They are also able to inhibit acetylcholinesterase. The aim of the diploma thesis was to process 34 kg of fresh bulbs of Narcissus cv. PROFESSOR EINSTEIN and to prepare an alkaloidal extract. This extract was further divided by column chromatography to almost 500 fractions which were merged based on TLC into 27 subfractions. The subfractione No. 17 was selected for isolation of at least one pure alkaloid. Preparative TLC was used for the the isolation. One pure compound was obtained in crystalic form which was then subjected to structural analysis by EI-MS and NMR methods. Further studies of biological activities were performed in...
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...
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...
Alkaloids of Amaryllidaceae family: isolation, structural identification, biological activity. I
Dohnalová, Alice ; Cahlíková, Lucie (advisor) ; Hošťálková, Anna (referee)
Dohnalova A: Alkaloids of Amaryllidaceae family: isolation, structural identification, biological activity. I; Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové, 2017, 64 p. The Amaryllidaceae family includes bulbous, beautifully flowering plants that have been used for thousands of years in traditional medicine. The major chemical compounds found in this particular plant family are alkaloids, namely Amaryllidaceae alkaloids. Until now, more than 500 isoquinoline alkaloids have been discovered, which exhibit a diverse biological activity including antitumor and antibacterial. They are also able to inhibit acetylcholinesterase. The aim of the diploma thesis was to process 34 kg of fresh bulbs of Narcissus cv. PROFESSOR EINSTEIN and to prepare an alkaloidal extract. This extract was further divided by column chromatography to almost 500 fractions which were merged based on TLC into 27 subfractions. The subfractione No. 17 was selected for isolation of at least one pure alkaloid. Preparative TLC was used for the the isolation. One pure compound was obtained in crystalic form which was then subjected to structural analysis by EI-MS and NMR methods. Further studies of biological activities were performed in...
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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