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Biologically active compounds of selected model trematodes
Kurečka, Martin ; Kameník, Zdeněk (advisor) ; Mikeš, Libor (referee)
Trematoda are parasites known for their ability to manipulate their host for survival and reproduction. They have complex life cycles with the intermediate host represented by mollusks and the definitive host, represented by vertebrates. This work focuses on three medically important genera of trematodes: Schistosoma, Fasciola and Opisthorchis. The aim of this work is to summarize biologically active low molecular weight substances that parasites modulate or produce in order to manipulate their host. The result of the work is a literature research of a comparative change in the concentration of metabolites of infected and uninfected trematode hosts with a focus on the analytical method used. Metabolomics deals with a comprehensive analysis of the metabolism of biological samples. It uses spectrometric analytical methods such as nuclear magnetic resonance and mass spectrometry combined with gas or liquid chromatography. Part of the work is also a summary of the importance, development and perspectives of metabolic profiling in parasitology. Current research in this area focuses mainly on vertebrate hosts. In addition, for vertebrate hosts, the sum of studied substances is still much broader than that in intermediate hosts. In intermediate host studies also focus on different types of substances,...
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Study of the presence of phenolic substances and their antioxidant activity in food products containing rosehip (Rosa canina L.)
Hronová, Vendula ; Mikulíková, Renata (referee) ; Kovalčík, Adriána (advisor)
This bachelor's thesis monitored the content of bioactive substances and antioxidant activity in the jams made of the fruit of rose hips (Rosa canina L.). The jams were sweetened with various sweeteners such as cane sugar, beet sugar, erythritol and stevia. Moreover, the rheological properties of jams were determined. The properties of home-made jams prepared from rosehip fruit were compared with the commercial jam. Another aim was to determine whether the by-products received after the production of jams could serve as beneficial sources of bioactive substances after the preparation of water extracts. The content of carbohydrates, polyphenols, flavonoids, and antioxidant activity were determined in jams and extracts spectrophotometrically. Next, the spectrophotometric detection of pectin, the chemical characterization of jams by infrared spectrometry, and the spectrophotometric determination of the jam colour were performed. The concentration of bioactive substances in jams was influenced by the geographical location and the time and weather conditions of harvest. The rheological properties and pectin content of the jams depended on the type of the used sweetener. The assessment of the water extracts prepared from the by-products after jam production and from the dried fruits of rosehip showed the high content of bioactive substances and high antioxidant activity in all tested extracts. The presented work points out that it is possible to prepare jams with superfood properties from the fruit of rose hips and extracts with high antioxidant activity.
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Analysis of streptomycete isolates carrying a cyclizing aminolevulinate synthase gene
Rašmanová, Petra ; Petříčková, Kateřina (advisor) ; Felsberg, Jurgen (referee)
Streptomyces bacteria are well-known producents of many bioactive metabolites. Its secondary metabolism is a source of many important groups of active compounds that are recently investigated by means of many new methods based on bioinformatic analyses of genome data, modern LC-MS techniques, and metabolic modeling methods. This thesis originates from the genetic screening for a specific gene (als) for cyclizing 5-aminolevulinate synthase. Based on earlier studies, we consider this gene as a genetic tag of the producers of secondary metabolites containing the C5N unit (2-amino-3-hydroxycyklopent- 2-enon). Such metabolites include several groups with variable structures and biological activities, which include manumycins as well. Manumycins are small polyketides with a weak antibiotic aktivity, especially against gram-positive bacteria. However, its cancerostatic and anti-inflammatory effects are of greater importance. Streptomyces monomycini BCCO10 1552 and Streptomyces capoamus BCCO10 1636 strains were found positive for the presence of the als gene in the targeted genetic screening. By the als phylogeny, they cluster near the producents of manumycin compounds. This thesis aimed to determine whether these new natural isolates produce any compounds containing C5N unit, and to characterize them in...
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Preparation of food supplement containing probiotic bacteria and components with anti-inflammatory effect
Horňáková, Nikola ; Němcová, Andrea (referee) ; Skoumalová, Petra (advisor)
The presented thesis discusses the issues of chronic inflammatory diseases of the digestive system and suggests the possibility of the alternative natural remedies improving the health conditions or prolonging the remission phase of IBD. The main goal is to design a probiotic supplement enriched by natural anti-inflammatory agents. Phytochemicals, concretely phenolic compounds, flavonoids, and carotenoids suppress harmful inflammatory processes by direct targeting the function of the immune cells or by inhibiting damaging oxidative stress in general. Therefore, there were several plants potentially rich for these biologically active substances selected. Concretely, blueberry (Vaccinium myrtillus), lingonberry (Vaccinium vitis-idaea), turmeric (Curcuma longa), peppermint (Mentha piperita), chamomile (Matricaria recutita), cinnamon (Cinnamomum zeylanicum), ginger (Zingiber officinale) and flax (Linum usitatissimum). The suitable parts of these plants were extracted by using a total of three different solvents – water, ethanol, and hexane for obtaining lipidic extracts. The concentration of total polyphenols, total flavonoids, total carotenoids, and the ascertainment of specific polyphenols was determined in the prepared extracts. These characteristics were enhanced by the measurement of antioxidant activity of the aqueous and ethanolic extracts. The interaction of individual samples with probiotic cultures (Bifidobacterium breve, Lactobacillus acidophilus) and the ability of extracts to influence the viability of probiotics in the model digestion process has been examined. The most interesting samples (aqueous extracts of blueberries, mint, chamomile, and cinnamon) were selected for further experiments. The possible cytotoxicity towards human intestinal epithelial cells was tested in vitro by the MTT tests utilizing the CaCo-2 cell line. Extracts showing the highest levels of beneficial phytochemicals and antioxidant activity, supporting the growth of probiotic cultures, and showing minimal cytotoxic effects on human intestinal cells were then co-encapsulated with probiotics into alginate particles of a diameter of 1 mm. Water extracts of mint, chamomile, and cinnamon have been chosen. The encapsulation efficiency of successfully entrapped probiotics and phenolic compounds was determined in prepared particles. Furthermore, the particles were studied during the process of model digestion, when the release of the desired substances in the various parts of the digestive system was observed and assessed whether the components would reach the crucial point of action – the colon. For the use of the proposed probiotic mixture as a dietary supplement, a recommended dose of 1 g has been determined. Lastly, possible adjustments such as lyophilization or sheathing by an extra protective polymerous layer, e.g. chitosan, were suggested to prolong the shelf life of the particles and volatile substances stability.
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Chemical and biochemical transformation of bioactive compounds
Šimášková, Ema ; Sokolová, Romana (advisor) ; Martínková, Markéta (referee)
Xenobiotics, such as pharmaceuticals, food additives, environmental pollutants, and dietary bioactive compounds in organism are metabolized by various enzymes, resulting in their bioactivation or detoxification. Identification of structure of resulting metabolites is important for their detection in bodily fluids and tissues for diagnostic and forensic purposes. This thesis reviews known biochemical processes and enzymes involved in xenobiotic metabolism, including cytochromes 450 (CYP) and flavine monooxygenases (FMO). Given that biochemical reactions are to a major extent composed of electron-transfer reactions (i.e. oxidation and reduction), the thesis includes a section dealing with the practical approaches to determination of the oxidative or reductive mechanism of bioactive compounds.
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Study of antimicrobial substances of ginger
Ciburová, Alena ; Skoumalová, Petra (referee) ; Veselá, Mária (advisor)
For thousands of years ginger rhizomes are used in traditional Chinese medicine. Because of his significant pungent flavour is commonly used in foods and beverages all over the world. Nowadays many of the beneficial pharmacological positive effects of ginger rhizomes are identified. Their occurrence is due to the high concentration of bioactive compounds. This thesis is focused on analysing of occurrence of bioactive compounds such as polyphenols and flavonoids and their influence on antioxidation and antimicrobial properties of samples of fresh and dried ginger. The results show that for extraction of bioactive compounds in different ginger samples is more suitable to use different types of extraction solvents. The highest antioxidation activity was measured for macerate of 100% bio ginger tea from Sonnentor company in 96% ethanol. Antimicrobial properties were showed only for 100% bio ginger tea against gram-positive bacteria Microccocus luteus.
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Evaluation of modifications in content of selected bioactive substances in flax (\kur{Linum usitatissimum} L.) seeds during germination
HAŠKOVÁ, Kateřina
This thesis focus on analysing effect of germination on some groups of bioactive compounds in flaxseed. We used flaxseed variety named Libra. Its germination was 10 days long, done in two different conditions: in the dark and fully iluminated for 24 hours daily. Samples were taken on 2nd, 4th, 6th, 8th and 10th day. Following analyses were performed: determination of dry matter content, lipid content, content of nitrogenous compounds, content of proteins and protein spectrum, chlorophyll content, content of total polyphenolic compounds and antioxidant activity. Content of dry mater was proved to decrease during germination as well as lipid content regardless of light conditions. Amount of nitrogenous compounds stayed relatively unchanged during germination. Whereas amount of proteins increased depending on duration of germination and light conditions. Hydrolysis of proteins during germination was proved by protein spectrum analysis. Content of chlorophyll inreased in light-germinated seeds only. Increasing effect of germination on total polyphenolic compounds content and antioxidant activity was proven as well. Moreover aproximately two-fold rise of values was reported after defatting of samples.
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The nutritional importance of legumes in human diet
Chalánková, Veronika ; Bušová, Milena (advisor) ; Dostálová, Jana (referee)
This Bachelor's thesis is focused on the nutritional importance of different kinds of legumes, their favorable and unfavorable nutritional properties and their effects on the human organism. Legumes (or pulses) are a very valuable food because of the content of many nutritionally important substances and are clearly a part of healthy diet. They are the most important plant source of protein and fiber and are classified as foods with a low glycemic index. Consumption of legumes is not too high among ordinary population. Doubts about legumes can be caused by the content of so-called antinutrients, which, for example, reduce the use of nutrients and may cause digestive problems. However, these substances can be eliminated by appropriate treatment. In addition, they are biologically active substances that also exhibit positive effects on human health, especially antioxidant and anti-carcinogenic, and thus can play a role in the prevention of both tumor and metabolic diseases. Nowadays they are still the subject of research. The practical part of this thesis includes a field survey of the offer of legumes and products with their contents in stores. The range of these products is very rich nowadays and greatly simplifies including legumes into diet. However, the consumers must be careful about the...
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Influence of some super-foods and their active components on human cells
Maslonková, Ivana ; Skoumalová, Petra (referee) ; Márová, Ivana (advisor)
The presented diploma thesis is focused on the study of composition and biological effects of some super-foods. Theoretical part deals with basic information about chosen superfoods and their bioactive substances. Further, theoretical part describes the overview of vesicular systems used for encapsulation and the most common methods of particle characterization. A brief review of cell cultures and cultivation of human cells is presented as well as methods for cytotoxicity a genotoxicity testing. In the experimental section, aqueous and ethanol extracts of super-foods were prepared. These extracts were then encapsulated into liposomal and combined PHB particles. Super-food extracts were characterized by spectrophotometrical methods in order to determine the content of polyphenols, flavonoids, anthocyanins, carotenes, chlorophyll, tannins, and antioxidant activity. The physico-chemical characteristics of prepared liposomal and combined particles were determined too. The particles with encapsulated extracts were further tested using the MTT assay and SOS chromotest to describe their potential cytotoxic and genotoxic effects.
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Aronia – the source of bioactive compounds
Štumarová, Klára ; Vespalcová, Milena (referee) ; Veselá, Mária (advisor)
The aim of this bachelor thesis is to research the possible antimicrobial activity of aqueous and ethanolic extracts of aronia berries and tea mixture containing aronia. Also, the antioxidant activity and the concentration of the biologically active substances - polyphenols, flavonoids and anthocyanins was determined. Theoretical part contains a summary of basic information about Aronia melanocarpa, chemical composition, use and health effects of substances contained in its fruits. The experimental part focuses on the antimicrobial activity of the extracts on microorganisms Bacillus subtilis, Serratia marcescens and Micrococcus luteus. Farther there is spectrophotometrical determination of antioxidant activity, polyphenolic compounds, flavonoids and anthocyanins. From the experiment results flow that the extracts have almost none antimicrobial ability except tea mixture extracted with hot water. This extract has inhibitory effect on M. luteus and growth supportive effect on B. subtilis. It has been found that aronia fruits and tea mixture are rich in polyphenols and flavonoids.
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