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Recipe of a food supplement based on bioactive substances isolated from Prunus spinosa
Červinková, Zuzana ; Hudečková, Helena (referee) ; Kovalčík, Adriána (advisor)
Blackthorn fruits (Prunus spinosa) are small blue-purple drupes containing a range of bioactive substances that give them diverse biological effects. They are traditionally used not only in folk medicine, as they are attributed with many preventive and therapeutic effects. The presented master´s thesis deals with the preparation and characterization of an ethanol extract and dietary supplements based on bioactive substances isolated from the fruits of blackthorn. The ethanol extract was prepared by maceration fresh Prunus spinosa fruits in 40% alcohol. The extract was analyzed for the polyphenols (2111.39±11.32 mg GAE/l), flavonoids (903.89±5.08 mg CAE/l) and anthocyanins (165.24±0.38 mg CGE/l) content, antioxidant (11.99±0.40 mmol TE/l) and antimicrobial activity, phenolic compounds profile and sugars profile. The ethanolic extract exhibited antibacterial effect against the gram-positive bacterium Micrococcus luteus and gram-negative bacterium Escherichia coli but was not effective against the yeast Candida glabrata. After gentle concentration on a vacuum evaporator, the extract was used to prepare a dietary supplement. Two types of dietary supplements were prepared, namely gelatine candies with blackthorn fruit extract and gelatine capsules filled with lyophilized fruit powder. The nutritional profile of these products, content of bioactive substances (i.e. total polyphenols, flavonoids, and anthocyanins), phenolic compound profile and antioxidant activity were characterized. Additionally, the release of polyphenols was monitored during a simulated in vitro digestion. The gelatine candies with different extract concentrations (5, 10, 15 and 20 %) were subjected to sensory evaluation, where the aim was to optimize the addition of the extract to the gelatine matrix. According to the preferences of the evaluators, the sample with 15 % extract was rated as the best in terms of overall taste. In the ranking test, this sample was ranked second, behind the sample with 5 % extract, which, on the other hand, received a worse sensory profile rating. The thesis also included monitoring the effect of freezing, lyophilization, and drying on the bioactive compounds content (i.e. total polyphenols, flavonoids, anthocyanins) and antioxidant activity of Prunus spinosa fruits. The highest contents of total polyphenols (57.49±0.33 mg GAE/g DW), flavonoids (45.75±0.12 mg CAE/g DW) and anthocyanins (6.41±0.19 mg CGE/g DW) were quantified in lyophilized fruits, but the highest antioxidant activity (281.72±0.70 mol TE/g DW) was observed in frozen fruits. A statistically significant moderately strong positive correlation (0.641) of antioxidant activity and total flavonoids was observed for the analyzed samples. The results of the thesis showed a great potential for the use of blackthorn berries in the nutraceutical industry, where they can contribute as active additives to increasing both the bioactive and nutritional quality of dietary supplements.
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Analytical approaches to study group interactions of azole pesticides with important biological active compounds
Kovač, Ishak ; Jaklová Dytrtová, Jana (advisor) ; Száková, Jiřina (referee) ; Navrátil, Tomáš (referee)
This dissertation presents a developed capillary electrophoresis method for analysing residues of triazole fungicides (TAF) from real samples ("Sweet cherry" tomato - Solanum lycopersicum L) and shows its potential application in environmental analysis. The developed method was validated in-house and characterised by a relatively short analysis time and low cost with sufficient LOD and LOQ. As an additional part of this dissertation, which rose from the tomato plants' treatment with TAF, we studied the impact of triazole fungicides on plant development and their impact on biologically active compounds. Determination of TAF residues from tomato peel carried out with capillary electrophoresis. Capillary electrophoresis is a versatile technique with minute amounts of sample required, with high efficiency in separating small molecules, such as selected TAF. The developed method, cyclodextrin-modified micellar electrokinetic chromatography, accomplished a baseline separation of the TAF mixture from tomato peel. The optimal conditions for separation were in the background electrolyte comprised of phosphoric acid and Tris (100 mM concentration, respectively), 20% v/v methanol, with apparent p[H+ ] 4.8. The constituents of the mixed micellar pseudo-stationary phase were ionic detergent sodium dodecyl...
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Atmospheric CO2 concentration, light intensity and nitrogen nutrition affect spring barley response to drought and heat stress
Findurová, Hana ; Veselá, Barbora ; Opoku, Emmanuel ; Klem, Karel
The aim of this study was to compare physiological responses of two spring barley varieties,\ndiffering in their oxidative stress tolerance, to drought and heat stress after pre-treatment under different\nirradiation regimes, CO2 concentrations, and nitrogen fertilisation levels. High light intensity, elevated\nCO2, and additional UV radiation increased flavonoid accumulation. Moreover, more flavonoids were\ninduced in oxidative stress-sensitive variety Barke. Combined drought and heat stress caused a large\ndecline in CO2 assimilation, whereas heat stress alone caused only minor changes. Under combined\nstress, plants grown under low light intensity and no UV irradiation performed the best despite their\nhigher initial water use efficiency and lower flavonoids content.
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Bioactive compounds in green spices
ARNOŠTOVÁ, Lucie
The bachelor thesis focuses on the determination of the total content of phenolic compounds, individual majority phenolic compounds and vitamin C, contained in sweet basil (Ocimum basilicum), coriander (Coriandrum sativum), dill (Anethum graveolens) and lovage (Levisticum officinale). Firstly, the total content of phenolic compounds was determined by spectrophotometric analysis using Folin Ciocalteau agent in extracts from fresh and dried herb samples. Afterwards, particular representatives of phenolic compounds in the lyophilized material were identified by high-performance liquid chromatography (HPLC). Then the content of vitamin C in fresh samples from all selected plants was measured using high-performance liquid chromatography (HPLC). The highest concentration of phenolic compounds was discovered in lovage. The highest content of particular phenolic substances, quercetin and kaempferol, was also proved in lovage.
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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.
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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.
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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 ±...
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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.
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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.
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