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The content of selected biologically active substances in wild plants traditionally used as vegetables
ŠUSTEROVÁ, Simona
A balanced diet should contain, in addition to essential nutrients, enough minority biologically active substances, such as essential vitamins and minerals. This group of substances include, for example, plant polyphenols, which act as effective antioxidants. A diet rich in natural antioxidant substances contributes to the prevention of serious civilization diseases, especially heart and blood vessels. People have always tried to enrich their diet with the resources of the biologically active substances. Particularly in spring, when stored foods lost their nutritional value, several wild plants came in. These have traditionally been used as a source of vitamins and other necessary substances. In our regions, they are traditionally a young nettle, but also some members of the family of crucifers. The aim of the bachelor thesis will be to select a set of suitable wild growing plants, to take samples for analysis and to determine the content of selected biologically active substances. A liquid chromatographic technique will be used to analyze the selected biologically active polyphenols contained in the plant material. It is a modern separation analytical technique, with which selected biologically active compounds are determined with high reliability.
Biologicky aktivní látky v netradiční listové zelenině.
FRIEDBERGEROVÁ, Markéta
Flavonoids are now increasingly coming to the forefront of interest not only from the scientific community but also of the public. They were found to be very beneficial in the field of prevention of cardiovascular or cancer diseases. In addition, they have proven to have antioxidant, anti-allergic or anti-inflammatory effects. In this bachelor 's thesis, the contents of substances, namely quercetin, kaempferol, morin, myricetin, apigenin and luteolin, were investigated using HPLC method. Lyophilized material of four varieties of Asian leafy vegetable from the cruciferous family was selected for analysis: Namenia, Sagami, Golden Lion and Tatsoi. All samples were grown in spring and autumn sowing period. Only two of the monitored aglycones, quercetin and kaempferol, were determined. The highest content of total quercetin was registered in the autumn sowing period of Namenia 1360 mg/kg of dry matter, the content of total kaempferol 1300 mg/kg of dry matter in the Golden Lion variety, also in autumn sowing period. After conversion to fresh mass, the highest concentrations of both aglycones were measured in Namenia during autumn sowing period. The amount of quercetin was determined to be 157 mg/kg of fresh weight, while the kaempferol content was 114 mg/kg of fresh weight.
STUDIES OF THE EFFECT OF ELICITORS TO AMOUNT OF CERTAIN ACTIVE INGREDIENTS IN WILD CHAMOMILE (CHAMOMILLA RECUTITA L. RAUCHERT)
ŠALÁT, František
This work is focused to prove effect of elicitors as stimulators of plant immunity on amount of biologically effective compounds in plant Matricaria recutita. For two years the field culture of Matricaria recutita was grown. As elicitor was used Acetylsalicylic acid (ASA) in different dose of elicitor (low, medium, high, neutral). Concentration of selected biological active substances in floss of Matricaria recutita plant was measured to prove the elicitation of the leaf application of elicitors.
Evaluation of flavonoids content in various species of Bergenia genus
Marková, Almíra ; Tůmová, Lenka (advisor) ; Karlíčková, Jana (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmacognosy and Pharmaceutical Botany Author: Almíra Marková Supervisor: Assoc. Prof. PharmDr. Lenka Tůmová, CSc. Title of diploma thesis: Evaluation of flavonoids content in various species of Bergenia genus Originally an Asian genus Bergenia from the family Saxifragaceae includes 32 species described so far and many hybrids that were created by crossing them. The leaves and rhizomes of bergenia used widely in folk medicine of China, India, Mongolia, and Russia are rich in a wide range of chemical constituents. The most important secondary metabolites of this plant are tannins, arbutin, bergenin, but also flavonoids. The drug is valued for its litholytic, antioxidant, anti-inflammatory, antipyretic, or antitussive properties. This work aimed to determine flavonoid content in red and green leaves of Bergenia crassifolia (L.) Fritsch, Bergenia ciliata (Haw.) Sternb. and Bergenia x ornata Guill. and their comparison with each other depending on the harvest period and climatic conditions. The samples were obtained from the botanical garden of the Faculty of Horticulture of Mendel University in Lednice. Flavonoid content was determined spectrophotometrically. The highest flavonoid content was measured in B. ciliata (1.1829 ±...
Isolation and characterization of beta-glucans of natural origin
Ratsilouskaya, Lizaveta ; Hoová, Julie (referee) ; Márová, Ivana (advisor)
The bachelor thesis deals with the characterization of natural beta-glucans and other active substances isolated from macroalgae and yeasts. The used macroalgae samples differ in the pigment, origin and method of algae processing. The theoretical part focuses on seaweed and yeast species, beta-glucans, their sources and biological effects, other biologically active substances (such as polyphenols and antioxidants) and finally on methods for determining these biologically active substances. In the practical part, samples of selected macroalgae were analyzed, namely samples of Arame, Nori, Kombu, Wakame, Hijiki and Spaghetti. Aqueous, ethanol and acetone extracts of these algae were prepared in this work. The aqueous extracts were used for spectrophotometric determination of phenolic substances, flavonoids and antioxidant activity by the ABTS method. Furthermore, ethanol and acetone extracts of said macroalgae were used to determine total chlorophyll and carotenoid content spectrophotometric. The work also focused on beta-glucan content, analyzing macroalgae and yeast R. toruloides. Arame and Nori algae and R. toruloides were high in beta-glucans. However, beta-glucans were very low in other macroalgae.
Pretreatment of hops for further processing in beer technology
Tichá, Anna ; Štursa, Václav (referee) ; Pořízka, Jaromír (advisor)
This diploma thesis deals with pre-treatment of hops for further processing in beer technology. In the experimental part of the work, the effect of low temperatures, as pre-treatment of hops, on the monitored parameters was observed. Three types of cold pretreatment were used. In two cases, the hop material was frozen using a freezer at -25 ° C and in the second case at -70 ° C. In the third case, the hop material was treated by contact with liquid nitrogen in combination with mechanical treatment. The variety of hop materiál was Žatecký poloraný červeňák, which were in the form of pellets or pressed hop cones. The total bitterness of the samples, the total content of phenolic substances, the total content of flavonoids, the antioxidant activity and the concentration of essential oils, specifically myrcene humulene and geraniol, were examined. The effect of pre-treatment was investigated during conventional worth boiling as well as dryhopping. The experimental part includes descriptions of the hopping process, descriptions of individual analytical methods. A parallel measurement was performed on each sample. Significant advantages or disadvantages of some of the pretreatments were not demonstrable, however, the most significant differences were observed in samples hopped with hops pretreated by freezing at -70 ° C, which had a positive effect on the amount of extracted essential oils during cold hops.
The electrochemical study of the degradation of the natural dyes from historical objects
Ramešová, Šárka ; Schwarzová, Karolina (advisor) ; Navrátil, Tomáš (referee)
The oxidation of quercetin (3,3',4',5,7-pentahydroxyflavone) and luteolin (3',4',5,7-tetrahydroxyflavone) has been studied. These intensively coloured polyphenolic compounds belong to a large group of naturally occuring flavonoid compounds. They were used with advantage as colourants in old tapestries. The study concerns the analysis of degradation processes of the original dyes. Degradation products formed during the ageing process can be used as fingerprints for the determination of the original colours. The degradation processes of flavonoid compounds were studied by electrochemical methods, absorption spectrometry and separation methods in aqueous media. The oxidation mechanism involves electron transfer coupled with chemical reaction and is influenced by the acidobasic properties of quercetin. The dissociation constants pK1 and pK2 of quercetin and pK1 and pK2 of luteolin were determined by combining of independent methods: acid-base titration and UV-Vis spectroscopy. The stability of both compounds significantly depends on the presence of the oxygen. The distribution of the oxidation products of quercetin in aqueous media within the exposure to oxygen was monitored by LC-MS/MS and LC- DAD analysis.
NADP-dehydrogenases of medicinal plants.
Bartošová, Martina ; Hýsková, Veronika (advisor) ; Kubíčková, Božena (referee)
Medicinal plants usually contain metabolites formed by secondary biosynthetic pathways for example phenylpropanoid and shikimate pathway, which depend on NAPDH availability. In this work total content of phenolic compounds and flavonoids was determined in 10 medicinal plants common for Czech Republic. Activity of enzymes providing NADPH was determined as well. These enzymes were glucose-6-phosphate dehydrogenase (G6PDH, EC 1.1.1.49), NADP-isocitrate dehydrogenase (NADP-ICDH, EC 1.1.1.42), NADP-malic enzyme (oxalacetate decarboxylating) (NADP-ME, EC 1.1.1.40). The activity of shikimate dehydrogenase (SDH, EC 1.1.1.25), the main enzyme of shikimate pathway, was also determined. Extraction methods were optimized for each assessment. Applicable source for NADP-dependent enzymes are black radish (Raphanus sativus L. var. niger), garlic (Allium sativum L.) and mint (Mentha piperita L). The highest content of phenolic compounds and flavonoids was determined in sage (Salvia officinalis), lemon balm (Melissa officinalis L.) and Mentha citrata. Extraction with methanol was more effective than extraction with hot water. More extraction methods and studies are necessary for characterization of individual compounds and principals on which they work. Key words: medicinal plants, NADP-dependent enzymes, phenolic...
Flavonoids in some cultivars of Sambucus nigra L. flowers.
Krulišová, Markéta ; Spilková, Jiřina (advisor) ; Martin, Jan (referee)
The aim of this work was to find out the content of flavonoids in the flowers of eleven cultivars of black elder (Sambucus nigra L.) and determine if their contents differ according to the statistical significance. Preparing the list of effects and substances that are contained in the flowers was the goal as well. The drug Sambuci nigrae flos is mostly used for its content of flavonoids and hydroxycinnamic acids in the therapy of colds and diseases of the urinary and respiratory tract. Its benefits were confirmed also by studies testing antibacterial and antiviral activity, diabetes and obesity, effects on the immune system and also protection against UV radiance. The content of flavonoids was established by the spectrophotometric method that is listed in the Czech Pharmacopoeia 2009 in the article Sambuci nigrae flos as the method for the determination of content. The statistic evaluation of the differences in the flavonoids content between the cultivars was made by ANOVA and the Bonferroni test. The demand of Czech Pharmacopoeia 2009 on the minimal content of flavonoids is 0,80%. This requirement was fulfilled in the flowers of these cultivars: Albida, Heidegg 13, Riese auß Voßloch, Sambu, Samdal, Sampo and Samyl. On the opposite side, flowers of the cultivars Allesö, Aurea, Dana and Juicy did...
Secondary metabolites of plant tissue culture of Trifolium pratense L.
Novotná, Hana ; Kašparová, Marie (advisor) ; Siatka, Tomáš (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmacognosy Candidate: Hana Novotná Supervisor: PharmDr. Marie Kašparová, Ph.D. Title of diploma thesis: Secondary metabolites of plant tissue culture of Trifolium pratense L. Explant cultures are perspective sources of secondary metabolites. Nevertheless production of flavonoids and isoflavonoids by the suspension culture of Trifolium pratense L. is not high. Elicitation is one of the methods used to enhance the biosynthesis of secondary metabolites. Elicitation induces physiological changes, stimulates defensive or stress-induced reactions in plants and subsequently triggers the synthesis of secondary metabolites. The objective of this study was to observe the influence of two elicitors - abscisic acid and ascorbic acid - on the production of flavonoids and isoflavonoids by the Trifolium pratense L. suspension culture (Sprint variety). The culture was cultivated in Gamborg medium to which 2 mg.l-1 of 2,4- dichlorophenoxyacetic acid and 2 mg.l-1 of 6-benzylaminopurine were added, at the temperature of 25 řC and 16 hours light / 8 hours dark period. The best elicitation effect of abscisic acid on the production of flavonoids and isoflavonoids was observed after a 6-hour application of the highest 500 µmol.l-1...

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