National Repository of Grey Literature 117 records found  1 - 10nextend  jump to record: Search took 0.00 seconds. 
The effect of pyrazine derivatives on secondary metabolites content in plant cultures in vitro - III.
Blahnová, Kristýna ; Tůmová, Lenka (advisor) ; Karlíčková, Jana (referee)
One of the possibilities how to increase the production of secondary metabolites (SM) in plant in vitro cultures is the method of elicitation. The aim of this work was to determine the effect of an abiotic elicitor from the class of pyrazine derivatives 1-benzyl-3-(pyrazin-2-yl)urea on the production of flavonolignans of silymarin complex and flavonoid taxifolin in the plant culture Silybum marianum (L.) Gaertn. Pyrazine derivatives are investigated for their herbicidal properties, so elicitation proceeds by the mechanism of stress inducing effect. Tissue cultures were grown on Murashige and Skoog growth medium with the addition of the growth regulator α-naphthylacetic acid. Elicitation was performed on both callus and suspension cultures. The elicitor was used in three different concentrations: c1 = 100.0 mg/100 ml; c2 = 10.0 mg/100 ml; c3 = 1.00 mg/100 ml. Particular samples were taken after 6, 24, 48, 72 and 168 hours of elicitor effect, control samples after 6, 48 and 168 hours. After drying, the callus and suspension tissues were extracted with methanol and the content of the monitored secondary metabolites was determined by HPLC. It was also tested if SM are released into the growth medium. Flavonolignans silybinin A and silybinin B were not detected in any of the analyzed samples. The...
The effect of abiotic elicitors on secondary metabolites content in plant cultures in vitro - II.
Tomaidesová, Barbora ; Tůmová, Lenka (advisor) ; Karlíčková, Jana (referee)
The Effect of Abiotic Elicitors on the Content of Secondary Metabolites in In vitro Plant Cultures - II. The method of elicitation is used for the increased production of secondary metabolites in in vitro plant cultures. In this study, there the effect of pyridine derivate N-(5-chlorpyridin-2-yl)-4-ethylbenzamide in three concentration - 3.845.10-3 mol/l; 3.845.10-4 mol/l and 3.845.10-5 mol/l for the production of flavonolignans in callus and suspension cultures of Silybum marianum was tested. The evaluation of elicitation effect proceeded after 6, 24, 48, 72 a 168 hours against control samples without the elicitor treatment after 24 and 168 hours. In the same intervals the samples of culture medium were taken and assessed. The cells were cultivated on Murashige and Skoog medium with 10 mg/ml of α-naphtylacetic acid as growth regulator. The obtained and adjusted samples were analysed by the HPLC method. From the parts of silymarin complex were detected silychristin, silybin A, isosylibin A, isosilybin B. Flavonoid taxifolin wasn̕ t detected in any case. In callus culture, there was achieved a maximal production of all detected components of silymarin complex (30.508 μg/g DW) after 168 hours of elicitor treatment in concentration of 3.845.10-4 mol/l, it was about only substance - silychristin. The...
Phytochemical analysis and biological activity of the alga Haematococcus pluvialis and Chlorella sp.
Fábryová, Tereza ; Tůmová, Lenka (advisor) ; Mučaji, Pavel (referee) ; Dohnal, Vlastimil (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Department of Pharmacognosy Candidate Mgr. Tereza Fábryová Supervisor doc. PharmDr. Lenka Tůmová, PhD. Title of Doctoral Thesis Phytochemical analysis and biological activity of the alga Haematococcus pluvialis and Chlorella sp. Nowadays, microalgae represent a novel and promising source of various bio-active compounds. This research work focuses on two carotenoids - astaxanthin and lutein, which are attracting interest from various industrial sectors. However, the production methods so far developed for obtaining these two valuable carotenoid pigments from microalgae imply time- and solvent-consuming operations. This work deals with two aspects. Firstly, the investigation and development of efficient and scalable isolation methods for producing the target carotenoids from microalgae biomass using high-performance countercurrent chromatography (HPCCC). Secondly, the investigation of the biological activity of astaxanthin and its esters, which have been little studied. In our study, lutein was isolated from the green microalgae Chlorella vulgaris using the lower phase of the biphasic solvent system composed of n-heptane-ethanol-water (5:4:1.5, v/v/v) (LP4), which served both as a solvent for microalgae biomass extraction and as...
The effect of abiotic elicitors on secondary metabolites content in plant cultures in vitro - I.
Teplá, Klára ; Tůmová, Lenka (advisor) ; Siatka, Tomáš (referee)
Plants are a source of a wide range of secondary substances, which due to their effects find use in many areas of focus. By a method called elicitation, we can achieve their higher and thus more efficient production. This diploma thesis aimed to determine whether the abiotic elicitor 2-(4-chlorophenyl)-N-(5-chloropyridin-2-yl)acetamide can positively affect the production of the flavonoid hyperoside in callus and suspension culture of Hypericum perforatum L. The elicitor was added to the in vitro cultures in three concentrations: C1 = 3,571.10-3 mol/l; C2 = 3,571.10-4 mol/l and C3 = 3,571.10-5 mol/l. A sample was taken at regular intervals after 6, 24, 48, 72 and 168 hours of elicitor treatment. Control samples were taken after 24 and 168 hours. The content of hyperoside produced was subsequently determined using High Performance Liquid Chromatography. Simultaneously, the amount of hyperoside released into the nutrient media of both plant cultures was also monitored. Maximum hyperoside production was recorded in suspension culture after 6 (17,7 µg/g DW) and 48 hours (3,69 µg/g DW) of elicitor treatment with the lowest concentration of C3 (3,571.10-5 mol/l). The content of hyperoside in the first case was 1770 % higher compared to the control sample. There was a significant release of hyperoside...
Can essential amino acids be considered as copper chelators?
Holotíková, Nikola ; Karlíčková, Jana (advisor) ; Tůmová, Lenka (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Botany Candidate: Nikola Holotíková Supervisor: PharmDr. Jana Karlíčková, Ph.D. Title of Thesis: Can essential amino acids be considered as copper chelators? Copper is a trace element playing an important role in the human organism. Copper levels in the body have to be carefully controlled because disruption of copper homeostasis can cause oxidative damage which may lead to various pathologies. Chelation of copper can potentially be used as a therapeutic tool. Medical chelators should ideally mimic chelators, especially peptides and proteins which are important for regulation of copper homeostasis. Their structure is formed by amino acids linked by peptide bonds. For this reason, the study is focused on selected amino acids. Proteinogenic amino acids are classified into essential and nonessential. Essential amino acids must be obtained from the diet. The aim of this study was to compare the copper chelation and reduction activity of essential amino acids L-histidine and L-methionine, and nonessential amino acids L-cysteine, its dimer L-cystine, L-aspartic acid and L-glutamic acid. Also a L-cysteine-derived compound, N-acetylcysteine, was tested. All of them were tested using spectrophotometric methods at pHs which...
Screening of New Iron - and Copper - Chelating Substances - in vivo and in vitro Studies
Říha, Michal ; Mladěnka, Přemysl (advisor) ; Patočka, Jiří (referee) ; Tůmová, Lenka (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Candidate: Michal Říha, MSc. First Supervisor: Assoc. Prof. Přemysl Mladěnka, Ph.D. Second Supervisor: Prof. Radomír Hrdina, M.D., Ph.D. Title of Doctoral Thesis: Screening of new iron- and copper-chelating substances - in vivo and in vitro studies Iron and copper are essential trace elements which play a role in a series of physiological processes in human organism. Homeostasis of these transition metals is meticulously regulated since free or loosely bound iron and copper can catalyse the production of free radicals. Hereditary hemochromatosis, transfusion hemosiderosis and Wilson's disease are associated with absolute iron and copper overload in the organism. Transition metal chelators have crucial significance for the treatment of these states. There are several other diseases with documented involvement of iron and/or copper in their pathophysiology. Examples are primarily neurodegenerative diseases, cardio- vascular diseases, tumours and diabetes mellitus. Various chelating compounds are examined in these possible indications. The aim of this doctoral thesis was to perform a screening of iron- and copper- chelating substances and to study their properties in detail using in vitro and...
Interactions of alkaloids with transition metals III.
Cymbál, Martin ; Macáková, Kateřina (advisor) ; Tůmová, Lenka (referee)
Charles University Pharmaceutical Faculty in Hradec Králové Department of Pharmaceutical Botany Candidate: Bc. Martin Cymbál, DiS. Supervisor: doc. Ing. Kateřina Macáková, Ph.D. Diploma thesis 2019/2020: Interactions of alkaloids with transition metals III., pp. 86. Copper is one of the important trace elements in the body. It regulates various enzymatic pathways. This work monitors the chelating and reducing activity of isochinoline alkaloids of the family Amaryllidaceae. The alkaloids of Amaryllidaceae have a large number of effects such as analgesic, narcotic, antiarrhythmic, antihypertensive, bronchodilatory, chemotherapeutic, antiparasitic, uteretonic, locally anesthetic, mydriatic and many other significant effects. An important representative is galanthamine hydrobromide, which is therapeutically used and is an inhibitor of acetylcholinesterase. Galanthamine type alkaloids (galanthamine, galanthamine hydrobromide, chlidanthine), lycorine type (lycorine, galanthine), haemanthamine type (haemanthnamine, vittatine) and montanine type (montanine) were studied. The methodology of the work was to determine the chelating and reducing activity with the use of the hematoxylin indicator and bathocuproindisulfonic acid, at different pH or in dimethylsulfoxide. Of the alkaloids studied, galanthamine and...
Interactions of alkaloids with transition metals II.
Šilhová, Markéta ; Macáková, Kateřina (advisor) ; Tůmová, Lenka (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical Botany Consultant: Ing. Kateřina Macáková, Ph. D. Student: Markéta Šilhová Title of Thesis: Interactions of alkaloids with transition metals II. Copper is an important component of the human body. It is involved in the right functioning of organ systems and is also a part of many important body enzymes. It is necessary to maintain a balanced amount of copper in the body in order to avoid excess or deficiency, which can lead to various diseases. The aim of this diploma thesis was to determine the copper chelating and copper reducing effects of isoquinoline alkaloids berberine chloride, canadine, corydaline, sculerine, sinactine, stylopine, tetrahydropalmatine, allocryptopine, protopine, corycavamine and cryptopine. In experimental measurements the determination of chelation of copper ions with hemytoxyline and the determination of chelation and reduction of copper ions using disodium salt of bathocuproindisulfonic acid was performed. The highest reducing activity was exhibited by scoulerine, whose structure in comparison with other alkaloids contains hydroxyl groups and which has been exhibited in the past to inhibit the growth of tumour cell. The lowest reducing activity was measured for protopine alkaloids and...
The effect of pyrazine derivatives on secondary metabolites content in plant cultures in vitro II.
Hanzlíková, Tereza ; Tůmová, Lenka (advisor) ; Karlíčková, Jana (referee)
The main purpose of the theses was to find if the abiotic elicitor 2,4,6-trimethyl-N-(pyrazine- 2-yl)benzenesulfonamide has any influence on the secondary metabolites production in callus and suspension cultures of Hypericum perforatum L. The cultivation was taking place in the Murashige a Skoog (MS) nutrient medium enriched by the growth regulator - alpha-naphthyl acetic acid at the concentration of 1 mg.L-1 . The elicitor was added to the cultures at the three levels of concentration: c1= 100.0 mg/100 ml; c2= 10.0 mg/100 ml; c3= 1.00 mg/100 ml. The individual samples were taken after 6, 24, 48, 72 and 168 hours of the elicitor application. The control samples without the elicitor were taken after 6, 48 and 168 hours. The collected samples were dried and subsequently transformed into methanol extracts in order to determine secondary metabolites content (rutin, hyperoside and quercetin) by HPLC method. Release of these metabolites into nutrient media was also subject of this observation. The elicitation has influenced production of the secondary metabolites, particularly in callus cultures, wherein several statistically significant values, characterizing increase in their production, were measured. The highest content of rutin (0.169 mg.g-1 DW) was determined in callus culture after 168 hours when...
Interactions of alkaloids with transition metals III.
Cymbál, Martin ; Macáková, Kateřina (advisor) ; Tůmová, Lenka (referee)
Charles University Pharmaceutical Faculty in Hradec Králové Department of Pharmaceutical Botany Candidate: Bc. Martin Cymbál, DiS. Supervisor: doc. Ing. Kateřina Macáková, Ph.D. Diploma thesis 2019/2020: Interactions of alkaloids with transition metals III., pp. 86. Copper is one of the important trace elements in the body. It regulates various enzymatic pathways. This work monitors the chelating and reducing activity of isochinoline alkaloids of the family Amaryllidaceae. The alkaloids of Amaryllidaceae have a large number of effects such as analgesic, narcotic, antiarrhythmic, antihypertensive, bronchodilatory, chemotherapeutic, antiparasitic, uteretonic, locally anesthetic, mydriatic and many other significant effects. An important representative is galanthamine hydrobromide, which is therapeutically used and is an inhibitor of acetylcholinesterase. Galanthamine type alkaloids (galanthamine, galanthamine hydrobromide, chlidanthine), lycorine type (lycorine, galanthine), haemanthamine type (haemanthnamine, vittatine) and montanine type (montanine) were studied. The methodology of the work was to determine the chelating and reducing activity with the use of the hematoxylin indicator and bathocuproindisulfonic acid, at different pH or in dimethylsulfoxide. Of the alkaloids studied, galanthamine and...

National Repository of Grey Literature : 117 records found   1 - 10nextend  jump to record:
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11 TŮMOVÁ, Lenka
9 TŮMOVÁ, Lucie
2 Tůmová, Linda
9 Tůmová, Lucie
2 Tůmová, Ludmila
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