National Repository of Grey Literature 41 records found  1 - 10nextend  jump to record: Search took 0.00 seconds. 
The problems of interaction testing compounds in ecotoxicology.
Pavlíčková, Ivana ; Pavlovský, Jiří (referee) ; Doležalová Weissmannová, Helena (advisor)
Bachelor thesis summarizes current knowledges of the problems of interaction of tested compounds and the determination of ecotoxicity. The work deals with the evaluation of ecotoxicity of binary mixtures of substances, toxic metals, or biologically active substances. The work is a brief summary of ecotoxicity tests used.
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.
Adsorption of biologically active substances in colloidal solutions of aminoclay
Málková, Ivana ; Pekař, Miloslav (referee) ; Mravec, Filip (advisor)
This paper builds on a previous study of magnesium aminoclay and its interactions with biological compounds. The theoretical part deals with the research of the usage of aminoclay as a carrier in medical applications, the method of its formulation, the selection of biologically active compounds and a suitable method of varification. The experimental part deals with the synthesis of aminoclay, samples preparation and study of the adsorption behavior of the selected bioactive compounds under different conditions. The experimental part of the paper also includes varification of the suitability of the selected UV VIS spektrometry to determine the adsorption behavior of the biologically active compounds in colloidal aminoclay solutions.
Characterization of active substances in several kinds of beer
Benešová, Pavla ; Obruča, Stanislav (referee) ; Márová, Ivana (advisor)
The aim of this bachelor thesis is to analyse biologically active compounds, especially of phenolic character, in 10 kinds of alcohol-free beer in comparison with alcoholic beer. In theoretical part basic steps of brewery technology are described including alcohol-free beer production. Characteristic compounds occurring especially in Czech beer e.g. proteins, phenolics, bitter substances and also methods for their analysis are discussed as well. Microfluidic electrophoresis (Experion, BioRad) was used to beer protein analysis. Phenolic compounds, flavonoids, technological characteristics and antioxidative activity were measured by spectophotometry. Individual phenolics of selected beers were identified and quantified by LC/ESI-MS analysis too. In alcohol-free beers similar concentrations of biologically active compounds were found in comparison with alcoholic beers, especially in the case of beer phenolics.
The Usage of Separation Methods for Research of Biologically Active Substances in Waters
Vydrová, Lucie ; Friedl, Zdeněk (referee) ; Opatřilová, Radka (referee) ; Chýlková,, Jaromíra (referee) ; Vávrová, Milada (advisor)
Pharmaceuticals are biological active compounds with different functional groups, physico-chemical and biological properties. These chemical compounds are called as “new contaminants” which cumulate in various environmental components. These contaminants input to environment from industrial processes, hospitals and health care institutions or household sources and these pollutants can to negatively interact with environmental components. Pharmaceuticals are separated according to structure and their effects to live organisms. On the basis of drug consumption in Czech Republic the non-steroidal anti-inflammatory drugs are the most using pharmaceuticals, because these drugs can be obtain without prescriptions. The choosing analgesics for study were monitored in waste water from waste waters treatment plant (WWTP Brno – Modřice) and in surface water from two sampling sites of river Kretinka. Pharmaceuticals were monitored in surface waters in Czech Republic, in Scotland (river Thurso) and in Taiwan (river Erren, Agongdian, Yanshuei and canal of Tainan) Solid phase extraction (SPE) is used for extraction of study pharmaceutical from water system. The high performance liquid chromatography (HPLC) with diode array detection or mass spectrometry was used for determination of drugs in surface waters from Czech Republic. The water samples from Scotland and Taiwan were analysed and the high performance liquid chromatography with mass spectrometry (HPLC/MS) was used for determination of pharmaceuticals. The method of HPLC/MS enables the determination of study compounds in the very low range of concentrations (ng ? l-1). All monitored pharmaceuticals were identified and quantified in water samples from river Kretinka in Czech Republic, river Thurso (Scotland) and rivers Erren, Agongdian, Yanshuei and canal of Tainan in Taiwan and the obtained data were compared.
Vliv zpracování borůvek na obsah biologicky aktivních látek
Balaščáková, Viktória
This thesis deals with the influence of blueberry processing on the content of bioactive compounds. The aim of the study was to determine and compare the content of bioactive compounds in six types of storage and processing of blueberries. Spectrophotometric analysis was used to determine the content of polyphenols, flavonoids, total antioxidant capacity determined by the TEAC method, and total antioxidant capacity determined by the DPPH method in frozen, oven-dried, freeze-dried, stored at 6 °C, and poorly stored blueberries of the Brigitta variety. The highest content of flavonoids was found in the freeze-dried samples and the lowest content was found in the frozen samples. The highest content of antioxidant capacity determined by the TEAC method was found in the freeze-dried samples. The second highest content of antioxidant capacity by the TEAC method was found in the oven-dried samples. Stored samples in the freezer had the lowest antioxidant capacity content determined by the TEAC method. Samples that were oven-dried had the highest antioxidant properties against free radicals, as determined by the DPPH method. The second-highest content of antioxidant capacity by the DPPH method was found in the freeze-dried samples. Conversely, the lowest value of antioxidant capacity determined by the DPPH method was found in samples frozen at -80°C and -20°C. The difference in values between the freeze-dried and oven-dried samples was very small when determined by the DPPH method. The results indicate that the lyophilization process was identified in this study as the most suitable for preserving bioactive compounds in blueberries.
Biologicky významné látky v bylinných čajích u čeledi hvězdnicovité
Stejskalová, Lenka
The importance of herbs and herbal teas is a frequently researched topic due to the content of biologically active substances. Plant material is a source of a large number of diverse components, which are proven to have a beneficial effect on the human organism. These substances are able to help in the prevention and possibly treatment of some human diseases. To fully understand the function of individual plants, it is necessary to know the content of individual groups of biologically active substances. The first part of this master's thesis named Biologically Important Substances in Herbal Teas of the Family Asteraceae escribes and defines herbal teas and organic farming. It also describes the Asteraceae family and focuses more specifically on selected species within this family, including marigold (Calendula officinalis), chamomile (Matricaria chamomilla L.), coltsfoot (Tussilago farfara L.) and coneflower (Echinacea purpurea). The consumption of herbal teas is currently high and still growing, therefore it is necessary to know the composition of the used plants. Representatives were chosen for their popularity and abundant use in the preparation of herbal teas. For each representative, there is a short botanical description and description of the contained substances. In the next chapter of the theoretical part, phenolic substances, their determination and effect on human health are presented. The group of flavonoids, which is a subgroup of phenolic substances, is described in more detail. The last section of the theoretical part explains the concepts of antioxidants, free radicals and methods of determining antioxidant activity. These groups were selected for measurement because they are substances showing effect on human health. In the practical part of this work, the total content of polyphenols, the total content of flavonoids and the total antioxidant capacity are determined in selected species. All these groups are determined spectrophotometrically. The essence of this work was to find out whether the content of these compounds in the same in samples from different productions. For each representative, one sample originating from organic farming (known as “BIO“) and one sample originating from conventional agriculture are examined. These two samples were statistically compared.
Aplication of separation methods for determination of biologically active substances
Bílková, Aneta ; Sklenářová, Hana (advisor) ; Česla, Petr (referee) ; Solich, Petr (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: RNDr. Aneta Bílková Supervisor: assoc. prof. PharmDr. Hana Sklenářová, Ph.D. Consultant: assoc. prof. PharmDr. Petr Chocholouš, Ph.D. Title: Application of separation methods for determination of biologically active substances The submitted dissertation thesis presents an annotated set of three publications, focusing on the application of separation methods for the determination of biologically active phenolic substances, pesticide residues in fruits, with regard to the use of modern storage technologies, and the application result - a utility model based again on monitoring the phenolic substances content with respect to different conditions of plant material drying. In the theoretical part, the target analytes are characterized from an analytical point of view, with respect to their physico-chemical properties, stability, antioxidantion activity. It also describes sample preparation methods for the determination of biologically active phenolic substances, selected extraction procedures and an overview of the methods used for the determination of the described substances in plant material. The main part of the dissertation deals with the development, optimization and validation of a rapid...
Antimicrobial organic nanomaterials containing extracts from microalgae and yeasts
Tushnolobova, Elizaveta ; Szotkowski, Martin (referee) ; Hoová, Julie (advisor)
This bachelor's thesis deals with the development of antimicrobial organic nanomaterials containing extracts of microalgae and yeasts. This work aims to synthesize and characterize these nanomaterials and investigate their biological effects and their potential in various applications, including medicine, food industry, industry, and environment. The basic principles of nanomaterials development are described in the thesis. Furthermore, the biological active compounds contained in microalgae and yeasts extracts and their potential in applications with antimicrobial effects are discussed. In the first experimental phase, biologically active compounds were extracted from microalgae and yeasts using extraction methods. These extracts were then used to prepare organic nanomaterials using synthetic procedures. Subsequently, these materials were characterized using various analytical techniques, including spectrophotometry. The next step was to test the biological effects of these nanomaterials. Their antimicrobial properties against various microorganisms, such as bacteria, were examined. The results of this work show that organic nanomaterials containing extracts of microalgae and yeasts have high potential as antimicrobial agents and can be used in various applications. These results can be beneficial for medical practice, the food industry, and environmental protection.
Use of some fractions of technical hemp in cosmetics
Gregarová, Lenka ; Hudečková, Helena (referee) ; Márová, Ivana (advisor)
Cannabis sativa is a versatile herb which is known for several thousand years and contains a variety of active substances. This thesis is focused on the use of some extracts of hem in cosmetics, specifically in hair cosmetics. The first part focuses on the Cannabis sativa, introducing the active contained substances and the overall processing of the plant. In the second part were experimentally determined the active substances in five extracts from different varieties, that were supplied from industry. Extracts were compared based on the extraction yield of antioxidants, chlorophylls, phenolic compounds, flavonoids and cannabinoids. Subsequently, a hair shampoo was prepared with the addition of hemp extracts and hemp hydrolysate. Lastly, the inhibitory effect against microorganisms was monitored for extracts and shampoos finally. Beneficial biologically active substances were detected in hemp extracts, wherein higher levels were measured in ethanol extracts. The extracts were also able to inhibit the growth of certain microorganisms. Satisfactory results on hair were observed with the prepared shampoo.

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