National Repository of Grey Literature 145 records found  beginprevious123 - 132nextend  jump to record: Search took 0.01 seconds. 
The influence of elicitation on the production of Trifolium pratense L. suspension culture.
Kyprová, Kateřina ; Siatka, Tomáš (referee) ; Kašparová, Marie (advisor)
Mgr. Kateřina Kyprová The influence of elicitation on the production of Trifolium pratense L. suspension culture. The proces of elicitation makes use of the kapacity of plants and plant cells cultivated in vitro to react to various stress stimuli by a number of protective reactions leading to increased accumulation of secondary metabolites. The paper examined the effect of four concentrations of calcium ions on the production of flavonoids and isoflavonoids by means in the suspension culture of Trifolium pretense L. which was elicited by an abiotic elicitor - 10 µmol solution of lead dichloride. The culture was cultivated on a Gamborg medium with an addition of 2,4-dichlorophenoxyacetic acid and 2 mg.l-1 6- benzylaminopurine. The maximal content of flavonoids found by a photometric determination according to Pharmacopoeia Bohemica 2005 was demonstrated in the suspension culture Trifolium pratense L. (0,355 %) after 6 hour administration of the elicitor and a 1 mmol calcium chloride solution. In comparison with the control and elicited groups, the production was stimulated by 63 % and 25 % respektively. The maximal content of isoflavonoids (genistin, daidzein, genistein, formononetin and biochanin A) found by a HPLC metod was demonstrated in the suspension culture Trifolium pratense L. (variety DO-9)...
The biological activity of compounds contained in plants XVIII. Antimicrobial activity of some secondary metabolites 2.
Váňová, Jana ; Siatka, Tomáš (referee) ; Opletal, Lubomír (advisor)
Váňová, J.: Biological Activity of Plant Metabolites XVII. Antimicrobial Activity of Some Secondary Metabolites 2. Rigorous Thesis, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové 2009, 106 pp. The antibacterial activity of 4 selected plant extracts was evaluated against E. coli O157:H7 and Staphylococcus aureus. Extracts were prepared by extraction in 80% ethanol and subsequent percolation. Two methods were used for determination of minimal inhibitory concentration (MIC). In the first case the values of MIC expected for E .coli on the basis of the other literature studies were not reached. All samples within the concentration range of 5 - 0,005 ppm which were prepared in two series were negative even after 48 hours exposition. In the second case better results were reached for E. coli and S. aureus. Two series of serial twofold dilutions within the concentration range of 25 %-0.02 % were prepared. The lowest values of MIC were exhibited by Thymus vulgaris extract, especially against Gram-positive indicator strain. Nevertheless the values of MIC remain very high (3.13 % for E. coli, 0.2 % for S. aureus). For determination of minimal bactericidal concentration (MBC) in E. coli O157:H7 and E. coli O55 seven essential...
Biological activity of plant metabolites. XVI. Alkaloids of Papaver somniferum L. and their activity to acetylcholinesterase
Filáková, Ivana ; Siatka, Tomáš (referee) ; Opletal, Lubomír (advisor)
Filáková, I.: Biological activity of plant metabolites XIV. Alkaloids of Papaver somniferum L. and their activity to acetylcholinesterase. Diploma thesis, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové 2010, 63 p. Within the screening of plants containing alkaloids potentially inhibiting human erythrocytic AChE and human butyrylcholinesterase was studied poppy (Papaver somniferum L) It was used 30 kg of poppy straw, basic extract was prepared by extraction of 95% alcohol. From this primary extract were prepared extracts with individual types of alkaloids by sequent procedue. In this diploma thesis only one extract was processed (extract type A-ether, pH 9 - 10). Alkaloids from this extract were separated into bases, where its chlorides are soluble and insoluble in chloroform. From each of above mentioned fractions phenolic and non-phenolic alkaloids has been obtained. In this work were separated alkaloids from extact AC1 (chlorides soluble in chloroform, non-phenolic. From this mixture was isolated thebaine by the using of column chromatogramy on alumina and preparative TLC on silica. This compound has been preliminary identified according to data of MS, melting point, optical rotary and by comparison with standard...
Suspension culture of Trifolium pratense L. II
Klabanová, Lenka ; Siatka, Tomáš (referee) ; Kašparová, Marie (advisor)
Lenka Klabanová Suspension Culture of Trifolium pratense L. II A principial precondition for succesful elicitation used to increase the production of secondary metabolities is finding a suitable elicitor, its concentration and the optimal period of time of the action of the elicitor on the plant culture in vitro. It was the aim of the present thesis. The effect was examined of a 6, 24, 48 and 168 hours action of the solution of aluminium trichloride (in concetrations 0,1 µmol, 1 µmol, 10 µmol, 100 µmol) on the production of flavonoids and isoflavonoids in the suspension culture of Trifolium pratense L. variety Tempus and Sprint. Culture was cultivated on a Gamborg medium with an addition of 2 mg.l-1 of 2,4-dichlorophenoxyacetic acid and 2 mg.l-1 of 6-benzylaminopurine, at the temperature of 25˚C and 16 hours light/8 hours dark period. The maximal content of flavonoids found by a photometric determination according to Pharmacopoeia Bohemica 2009 was demonstrated in the suspension culture of Trifolium pratense L. variety Tempus (0,276%) after a 168hour action of the elicitor of the 100 μmol concentration. Compared with the control culture was stimulated production of 283%. In Trifolium pratense L. variety Sprint found a maximal content (0.308%) after a 24hour action of the elicitor of the 10 μmol...
Biological activity of plant metabolites XII. Alkaloids of the family Corydalis DC. (Fumariaceae) and their biological activity
Salačová, Kateřina ; Siatka, Tomáš (referee) ; Opletal, Lubomír (advisor)
Salacova K.: Biological activity of plant metabolites. XII. Alkaloids of genus Corydalis DC. (Fumariaceae) and their biological activities. Diploma thesis, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové 2009, 83 p. The literature search focused on isoquinoline alkaloids of the genus Corydalis was carried out. The summary offers information about the chemical structure of alkaloids and the species of Corydalis (or morphological parts of the mother plant) from which the alkaloids were isolated. The biological activity of alkaloids and extracts from plants of the genus Corydalis was also described. Some species of the genus Corydalis present antifungal effects (C. incisa, C. longipes, C. chaerophylla), cytotoxic effects (C. incisa), hepatoprotective effects (C. saxicola), antithrombic effects (C. koidzumiana, C. ambigua), sedative, hypnotic and spasmolytic effects (C. pseudoadunca), anti-inflammatory and inhibitory effect on allergic reactions (C. turtschaninovii f. yanhusuo), inhibitory effect on acetylcholinesterase (C. bulbosa, C. turtschaninovii f. yanhusuo, C. cava, C. speciosa). Keywords: genus Corydalis, isoquinoline alkaloids, biological activity, acetylcholinesterase
Antiradical activity of Fagopyri herba extracts.
Mikšátková, Petra ; Siatka, Tomáš (referee) ; Spilková, Jiřina (advisor)
0 Abstract Petra Mikšátková Fagopyrum sp. (Polygonaceae), especially Fagopyrum esculentum Moench (common buckwheat) and Fagopyrum tataricum Gaertn (tartary buckwheat), which are most frequently used, contain some substances affecting living organism. They have an anticarcinogenic and hypotensive effect. They reduce fragility of blood vessels and also affect the progress of atherosclerosis. For their nutritional value they are used as food. Most of these properties are result of an antioxidant activity of a group of substances, flavonoids. Antioxidant activity of Fagopyri herba was evaluated by two methods using the free radical 2,2,-diphenyl-1-picrylhydrazyl (DPPH) and superoxide. By the DPPH assay, the methanol extract and the lyophilized water extract were evaluated. Their IC50 were compared with standards and the antioxidant activity decreased in the order: hyperosid (IC50 = 0,004 mg/ml) ≥ rutin (IC50 = 0,005 mg/ml) › methanol extract (IC50 = 0,105 mg/ml) › lyophilized water extract (IC50 = 0,2945 mg/ml). By the superoxide assay the lyophilized water extract was evaluated. When compared with standards, antioxidant activity decreased in this order: rutin (IC50 = 0,0242 mg/ml) › ascorbic acid (IC50 = 0,0692 mg/ml) › trolox (IC50 = 0,1192 mg/ml) › lyophilized water extract (IC50 = 0,3169 mg/ml).
Biologically active metabolites of plants. 3. Alkaloids from Chelidonium majus L. and their inhibiting activity to acetycholinesterase.
Šebestová, Lenka ; Siatka, Tomáš (referee) ; Cahlíková, Lucie (advisor)
Šebestová L.: Biologically active metabolites of plants. 3. Alkaloids from Chelidonium majus L. and their inhibiting activity to acetylcholinesterase. Diploma thesis, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové 2010, 68 p. The thesis aims to process the shake-out of benzophenanthridine alkaloids, of Chelidonium majus, to isolate at least one alkaloid in pure form; consequently the thesis aims to give exact figures for the anti-cholinesterase, anti-protozoal a antioxidant activity of the alkaloid. The method of column chromatography was used to isolate the two alkaloids of the shake-out. The isolated substances were labelled LŠ1 and LŠ2 respectively. The identification of the substances as stylopine.and chelidonine respectively, was based on NMR and MS studies. Both isolated alkaloids were subjected to inhibition study with respect to human erytrocytal acetylcholinesterase and human seral butyrylcholinesterase. Stylopin showed the following set of results: IC50 (AChE) = 114 ± 2.9 µM, IC50 (BuChE) = >1000 µM. The results being considerably higher in comparison with the standard used, no further usage for the treatment of Alzheimer's disease is expected. Chelidonine showed the following set of results: IC50 (AChE)...
Abiotic elicitation of explant culture of Trifolium pratense L.
Fiedlerová, Gabriela ; Siatka, Tomáš (referee) ; Kašparová, Marie (advisor)
Abiotic elicitation of explant culture of Trifolium pratense L. Summary The objective of this dissertation was to observe the effect of the abiotic elicitors of mercuric chloride and cadmium chloride on the production of flavonoids, and also of the effect of the mercuric chloride elicitor on the production of isoflavonoids in the Trifolium pratense L. explant culture (variety DO−8). The cultures were cultivated in the Gamborg nutrient media with the addition of 2,4−dichlorphenoxyacetic acid (2 mg.l-1 ) and 6−benzylaminopurine (2 mg.l-1 ), in the temperature of 25 řC and during a 16-hours light/8-hours dark period. The quantity of flavonoids was determined spectrophotometrically according to The Czech Pharmacopoeia 2005. The quantity of isoflavonoids was determined by the HPLC method. We can see from the results of this dissertation that the concentration 10 μmol of both of the used abiotic elicitors had the greatest positive effect on the production of flavonoids. The largest quantity of flavonoids (0,576 %) was detected during the elicitation of cadmium chloride of a 10-μmol concentration and after 48−hour application when the quantity of flavonoids increased by statistically significant 294 % in relation to the control sample. The quantity of isoflavonoids was determined by the HPLC method during the...

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