|
|
Isolation of alkaloids of the species Geissospermum vellosii Allemão and study of their biological activity IV.
Emrichová, Eliška ; Šafratová, Marcela (advisor) ; Hradiská Breiterová, Kateřina (referee)
Eliška Emrichová: Isolation of alkaloids of the species Geissospermum vellosii Allemão and study of their biological activity IV. Diploma thesis 2020. Charles University, faculty of Pharmacy in Hradec Králové, Department of Pharmacognosy. Key words: Geissospermum vellosii, bark, alkaloidal extracts, isolation of alkaloids, GC/MS analysis, biological aktivity, acetylcholinesterase, butyrylcholinesterase. The aim of this study was to isolate at least one pure alkaloid from the extract of Geissospermum vellosii Alemão bark. The whole process involved bark processing, to obtain summary and alkaloid extract and subsequent column chromatography. GV-4, one of the 16 obtained fractions, was separated into 5 subfractions. The GV-4bsubfraction was used to isolate pure alkaloids, processed by preparative thin layer chromatography and crystallization of pure compound. The structure of pure compound was determined by using NMR, GC-MS analysis and optical rotation. This compound was identified as anhydropereirine and was tested its inhibitory activity against human cholinesterases, AChE and BuChE. The alkaloids GV-1-a, GV-8-3-B, GV-9-c were isolated in the course of further work on the extract. Their inhibitory activity against GSK-3β was tested as well as their possibility to cross the blood-brain-barieer with...
|
|
|
Isolation of alkaloids of the species Geissospermum vellosii Allemão and study of their biological activity VII.
Strašková, Veronika ; Šafratová, Marcela (advisor) ; Hradiská Breiterová, Kateřina (referee)
Strašková, V.: Isolation of alkaloids of the species Geissospermum vellosii Allemão and study of their biological activity VII. Diploma thesis, Charles University, Pharmaceutical Faculty in Hradec Králové, Department of pharmacognosy and pharmaceutical botany, Hradec Králové 2023, 75 s. Key words: Geissospermum vellosii, bark, alkaloidal extracts, isolation of alkaloids, GC/MS analysis, biological activity, acetylcholinesterase, butyrylcholinesterase. The main goal of this diploma thesis was isolation of pure alkaloids from the stem bark of Geissospermum vellosii and test their biological activity. G. vellosii is a South American tree from the Apocynaceae family. It is used in traditional medicine for various pathological conditions (e.g., bacterial, inflammatory, and fungal diseases). Indole alkaloids isolated from the stem bark of this tree exhibit significant biological activities such as antineoplastic, antimalarial, and anticholinesterase activities. For processing, the GV-2, GV-7-D, and GV-4-F fractions were selected in this diploma thesis. These fractions were obtained in previous studies from the original alkaloid extract of the stem bark, which showed interesting inhibitory activity against AchE and BuChE (AChE: IC50 = 15,19±0,96 µg/ml, BuChE: IC50 = 0,37±0,049 µg/ml). Four alkaloids,...
|
|
|
Isolation of alkaloids of the species Geissospermum vellosii Allemão and study of their biological activity IV.
Emrichová, Eliška ; Šafratová, Marcela (advisor) ; Hradiská Breiterová, Kateřina (referee)
Eliška Emrichová: Isolation of alkaloids of the species Geissospermum vellosii Allemão and study of their biological activity IV. Diploma thesis 2020. Charles University, faculty of Pharmacy in Hradec Králové, Department of Pharmacognosy. Key words: Geissospermum vellosii, bark, alkaloidal extracts, isolation of alkaloids, GC/MS analysis, biological aktivity, acetylcholinesterase, butyrylcholinesterase. The aim of this study was to isolate at least one pure alkaloid from the extract of Geissospermum vellosii Alemão bark. The whole process involved bark processing, to obtain summary and alkaloid extract and subsequent column chromatography. GV-4, one of the 16 obtained fractions, was separated into 5 subfractions. The GV-4bsubfraction was used to isolate pure alkaloids, processed by preparative thin layer chromatography and crystallization of pure compound. The structure of pure compound was determined by using NMR, GC-MS analysis and optical rotation. This compound was identified as anhydropereirine and was tested its inhibitory activity against human cholinesterases, AChE and BuChE. The alkaloids GV-1-a, GV-8-3-B, GV-9-c were isolated in the course of further work on the extract. Their inhibitory activity against GSK-3β was tested as well as their possibility to cross the blood-brain-barieer with...
|
|
|
Isolation of alkaloids of the species Geissospermum vellosii Allemão and study of their biological activity VI.
Váňová, Lucie ; Šafratová, Marcela (advisor) ; Chlebek, Jakub (referee)
Lucie Váňová: Isolation of alkaloids of the species Geissospermum vellosii Allemão and study of their biological activity IV. Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmacognosy and Pharmaceutical Botany, Hradec Králové 2022. Key words: bark, Geissospermum vellosii Allemão, alkaloids, preparative TLC, GC-MS, NMR, (+)-19,20-dehydrotubifolidine, aspidolimidine, geissoreticulatine, inhibition activity, AChE, BuChE, Alzheimer's disease The aim of this diploma thesis was the isolation of at least 3 alkaloids in pure form from the GV-5 fraction, which was extracted from the bark of the South American tree Geissospermum vellosii Allemão. By using preparative thin layer chromatography (TLC), 9 subfracions (GV-5-A až GV-5-I) were acquired from this fraction. Those that were of sufficient mass were subsequently subjected to further division. Three alkaloids in pure form were isolated through purification using preparative TLC: GV-5-B-3-A, GV-5-C-4-C, GV-5-C-2-B-1. Gained active substances from this plant were analyzed by gas chromatography- mass spektrometry (GC-MS) and nuclear magnetic resonance (NMR). By comparing the obtained alcaloid's spectra with available data and literature, those alkaloids were identified as: (+)-19,20-dehydrotubifolidine...
|
|
|
Isolation of alkaloids of the species Geissospermum vellosii Allemão and study of their biological activity VIII.
Pelnář, Tomáš ; Šafratová, Marcela (advisor) ; Siatka, Tomáš (referee)
ISOLATION OF ALKALOIDS OF THE SPECIES GEISSOSPERMUM VELLOSII ALLEMÃO AND STUDY THEIR BIOLOGICAL ACTIVITY VIII. PELNÁŘ T. 1 , JANOUŠEK J. 2 , HRADISKÁ BREITEROVÁ K. 1 , ŠAFRATOVÁ M. 1 1 Department of Pharmacognosy and Pharmaceutical Botany, Faculty of Pharmacy in Hradec Králové, Charles University in Prague, Czech Republic 2 Biomedical Research Center, University Hospital in Hradec Králové, Czech Republic e-mail: pelnart@faf.cuni.cz The aim of this work was to determine the activity of indole alkaloids, including their separation and purification from the South American tree Geissopsermum vellossi, which is used in traditional medicine to treat various diseases. It shows possible use in the treatment of benign prostatic hyperplasia, tumor treatment, plasmodial diseases, and especially cognitive disorders. The isolated structures were subsequently tested for inhibition of human cholinesterases.1 These substances could be used to treat Alzheimer's disease, which has been increasing in recent years. We are not yet able to stop disease, just slow it down. The starting product was a summary alkaloid extract from crushed tree bark, which showed very interesting activity against AChE and BChE (IC50 = 15,19±0,96 µg/ml for AChE and IC50 = 0,37±0,049 µg/ml for BChE). The GV-4 fraction has been processed using...
|
|
|
Isolation of alkaloids of the species Geissospermum vellosii Allemão and study of their biological activity VI.
Váňová, Lucie ; Šafratová, Marcela (advisor) ; Chlebek, Jakub (referee)
Lucie Váňová: Isolation of alkaloids of the species Geissospermum vellosii Allemão and study of their biological activity IV. Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmacognosy and Pharmaceutical Botany, Hradec Králové 2022. Key words: bark, Geissospermum vellosii Allemão, alkaloids, preparative TLC, GC-MS, NMR, (+)-19,20-dehydrotubifolidine, aspidolimidine, geissoreticulatine, inhibition activity, AChE, BuChE, Alzheimer's disease The aim of this diploma thesis was the isolation of at least 3 alkaloids in pure form from the GV-5 fraction, which was extracted from the bark of the South American tree Geissospermum vellosii Allemão. By using preparative thin layer chromatography (TLC), 9 subfracions (GV-5-A až GV-5-I) were acquired from this fraction. Those that were of sufficient mass were subsequently subjected to further division. Three alkaloids in pure form were isolated through purification using preparative TLC: GV-5-B-3-A, GV-5-C-4-C, GV-5-C-2-B-1. Gained active substances from this plant were analyzed by gas chromatography- mass spektrometry (GC-MS) and nuclear magnetic resonance (NMR). By comparing the obtained alcaloid's spectra with available data and literature, those alkaloids were identified as: (+)-19,20-dehydrotubifolidine...
|
|
|
Isolation of alkaloids of the species Geissospermum vellosii Allemão and study of their biological activity VIII.
Pelnář, Tomáš ; Šafratová, Marcela (advisor) ; Siatka, Tomáš (referee)
ISOLATION OF ALKALOIDS OF THE SPECIES GEISSOSPERMUM VELLOSII ALLEMÃO AND STUDY THEIR BIOLOGICAL ACTIVITY VIII. PELNÁŘ T. 1 , JANOUŠEK J. 2 , HRADISKÁ BREITEROVÁ K. 1 , ŠAFRATOVÁ M. 1 1 Department of Pharmacognosy and Pharmaceutical Botany, Faculty of Pharmacy in Hradec Králové, Charles University in Prague, Czech Republic 2 Biomedical Research Center, University Hospital in Hradec Králové, Czech Republic e-mail: pelnart@faf.cuni.cz The aim of this work was to determine the activity of indole alkaloids, including their separation and purification from the South American tree Geissopsermum vellossi, which is used in traditional medicine to treat various diseases. It shows possible use in the treatment of benign prostatic hyperplasia, tumor treatment, plasmodial diseases, and especially cognitive disorders. The isolated structures were subsequently tested for inhibition of human cholinesterases.1 These substances could be used to treat Alzheimer's disease, which has been increasing in recent years. We are not yet able to stop disease, just slow it down. The starting product was a summary alkaloid extract from crushed tree bark, which showed very interesting activity against AChE and BChE (IC50 = 15,19±0,96 µg/ml for AChE and IC50 = 0,37±0,049 µg/ml for BChE). The GV-4 fraction has been processed using...
|
|
|
Isolation of alkaloids of the species Geissospermum vellosii Allemão and study of their biological activity IV.
Emrichová, Eliška ; Šafratová, Marcela (advisor) ; Hradiská Breiterová, Kateřina (referee)
Eliška Emrichová: Isolation of alkaloids of the species Geissospermum vellosii Allemão and study of their biological activity IV. Diploma thesis 2020. Charles University, faculty of Pharmacy in Hradec Králové, Department of Pharmacognosy. Key words: Geissospermum vellosii, bark, alkaloidal extracts, isolation of alkaloids, GC/MS analysis, biological aktivity, acetylcholinesterase, butyrylcholinesterase. The aim of this study was to isolate at least one pure alkaloid from the extract of Geissospermum vellosii Alemão bark. The whole process involved bark processing, to obtain summary and alkaloid extract and subsequent column chromatography. GV-4, one of the 16 obtained fractions, was separated into 5 subfractions. The GV-4bsubfraction was used to isolate pure alkaloids, processed by preparative thin layer chromatography and crystallization of pure compound. The structure of pure compound was determined by using NMR, GC-MS analysis and optical rotation. This compound was identified as anhydropereirine and was tested its inhibitory activity against human cholinesterases, AChE and BuChE. The alkaloids GV-1-a, GV-8-3-B, GV-9-c were isolated in the course of further work on the extract. Their inhibitory activity against GSK-3β was tested as well as their possibility to cross the blood-brain-barieer with...
|
|
|
Isolation of alkaloids of the species Geissospermum vellosii Allemão and study of their biological activity III.
Růžička, Lukáš ; Šafratová, Marcela (advisor) ; Hulcová, Daniela (referee)
Růžička, L. Isolation of alkaloids from Geissospermum vellosii Allemão and study of their biological activity. Diploma thesis, Department of pharmacognosy, Faculty of Pharmacy in Hradec Králové, Charles University, Czech Republic, 2020. The aim of this diploma thesis are alkaloids from Geissospermum vellosii. This tree native in South America is commonly used for treatment of various diseases, including cognitive deficits in elder people1 . The study is based on previous research that was focused on inhibition of human cholinesterases and glycogensynthase 3 β(GSK-3 β), which can be used in treatment of Alzheimer disease. Incidence of this disease is rising up in the last decades and it represents a big burden for both health service and economy of developed countries2 . Isolation was carried out from crude crushed stembark. After extraction and agitation, 50.4 g of thick yellowish ether extract was obtained. This extract showed activity against cholinesterases (IC50 AChE = 15.19 ± 0.96 μg/ml and IC50 BuChE = 0.37 ± 0.049 μg/ml). Later, this extract was separated to 16 fractions by column chromatography. Fraction GV9 was chosen for additional research. Thin layer chromatography was carried out for purification and extraction of white crystalline alkaloid. Structure was determined by...
|
guest ::
