|
|
Vitamin C
Juráňová, Jana ; Hrstka, Miroslav (referee) ; Vespalcová, Milena (advisor)
The theme of this diploma thesis is an assessment of given nutritional parameters in selected kinds of lesser known fruits, specifically 10 varieties of sea buckthorn (Hippophae rhamnoides L.), 12 varieties of cornelian cherry (Cornus mas L.) and 6 varieties of blue honeysuckle (Lonicera caerulea var. kamtschatica). Harvests of two consecutive years (2011 and 2012) were analyzed in the case of blue honeysuckle. The theoretical part was focused on historical, morphological, taxonomic and nutritional aspects of individual plants and food or pharmaceutical utilization. The considerable part of the thesis is devoted to the characterization and the possibilities of determining the contained substances, namely ascorbic acid and polyphenolic compounds, especially anthocyanins. The content of the experimental part was a description of the methods and the results of the analysis of total solids, titratable acidity, total phenolics, total anthocyanins and ascorbic acid in fruits of the selected varieties of the above mentioned fruit species. Based on the measured results, the different varieties of fruits were compared to each other and evaluated.
|
|
|
Determination of total protein, carbohydrates and polyphenols in beer
Dostálová, Blanka ; Gregor,, Tomáš (referee) ; Diviš, Pavel (advisor)
This master‘s thesis deals with the analysis of 65 different beers, with a focus on finding differences between Czech tap ales, lagers Czech, Czech special beers and foreign beers. Czech beers were compared by the results of analysis among beers bearing the indication "Czech beer" and the group without this indication. The total amount of proteins, polyphenols and carbohydrates was determined using UV-VIS spectrometry. The history of brewing, the nature and types of Czech beers and protected geographical indication "Czech beer" were described. Raw materials for beer production and brewing technology have been listed and described. In the last part of the research, components of beer and the principle of the UV-VIS spectrometry have been specified. Th determination of total protein was performed using Hartree-Lowry method, which is based on two-component reagent. The first component is the biuret agent, the second component is the Folin-Ciocalteau reagent for phenols. Determination of the polyphenols has been carried out by the Folin-Ciocalteau reagent and total carbohydrates were determined spectrophotometrically according to the Analytica EBC using anthron agent. The results were statistically processed and evaluated in the final part.
|
|
|
Determination of athenticity of plant foods by molecular techniques
Plášková, Anna ; Mikulíková, Renata (referee) ; Němcová, Andrea (advisor)
The aim of presented diploma thesis was to determination of authenticity of fruit baby foods for early infant feeding using molecular methods. In the experimental part, isolation kit was used for isolation of plant DNA from fruits (strawberry, apricot, raspberry, apple) and from six commercial fruit products for children. Isolated DNA was characterized and verified using PCR methods with primers specific for plant rDNA (ITS2). Specific primer pairs were designed to amplify DNA for the detection of one fruit species. Primer specificity was assessed with four fruit species. A mixture of fruit puree from the two fruits was used to determine the sensitivity of the multiplex PCR assay. Six commercial fruit products were evaluated to verify the applicability of the multiplex PCR assay. The methodology of molecular detection of fruit DNA by qPCR and multiplex qPCR (duplex) includes approaches, which enable to detect two fruits (strawberry-raspberry, apricot-apple) in one reaction and thus reduces time and money requirements.
|
|
|
Development of a new type of energy drinks containing natural active components
Vysoká, Marie ; Němcová, Andrea (referee) ; Skoumalová, Petra (advisor)
The aim of this thesis is the development and preparation of a new energy drink. The theoretical part of the thesis focuses on the comparison of the drinks available in market, the presentation of the main active ingredients and the proposal of enriching the new energy drink. It also describes the possibility of using an encapsulation and the method used to determine specific compound in energy drink or encapsulated particles. In the experimental part of the work, at the beginning, the main content of energy drinks were characterized, for instance caffeine, sugar, polyphenol and vitamin C. Subsequently the energy drink based on selected types of loose teas that were enriched with the encapsulated extract of acai, acerola, maca, goji and ginseng was designed. All extracts contained large amounts of polyphenols and antioxidants. In addition, acerola extracts contained very high amounts of vitamin C. Two types of particles, alginate particles and liposomes were prepared for encapsulation. For all particles, encapsulation efficiency, size, stability, and antioxidant activity were determined. Long-term stability was then monitored within three months. The particles were also exposed to artificial gastric, pancreatic and bile juice. All tested particles showed very good encapsulation efficiency. In terms of long-term storage stability in an aqueous environment. Particularly liposome particles, which also showed high stability by zeta potential measurement, were suitable. On the contrary, in case of alginate particles, when stored in an aqueous medium, the release of active substances occurred. Finally, an energy drink was created and subjected to sensory analysis. The best energy drink was based on black or green tea with alginate particles acai, goji and ginseng.
|
|
|
Natural drugs in cancer treatment and their cytotoxicity
Hájková, Tereza ; Raudenská, Martina (referee) ; Provazník, Ivo (advisor)
The thesis deals with the natural substances in context with the cancer disease. The natural substances have a positive effect on the human organism and they are able to influence the viability and the growth of the cancer cells. The main mechanical device is to influence the mechanisms needed to start the apoptosis of the cancer cells and stopping further proliferation. The cancer cell lines utilization in the cancer disease is discussed in the thesis too. The thesis states common methods of determining the natural substances cytotoxicity. For the experimental part of the thesis it was chosen the MTT test method and the xCELLigence system for monitoring in real time. The mechanical device of the tested substance capsaicin in application on the prostate cell lines, tumorous PC3 and nontumorous PNT1A influence will be observed within the experimental part of the thesis.
|
|
|
Characterization of edible films with the potential usage in food packaging
Jančíková, Simona ; Vítová, Eva (referee) ; Veselá, Mária (advisor)
In the last years, the edible packaging has been gaining popularity due to the potential usage as the packaging for food instead of synthetic materials. The edible packaging can positively affect the packaged food by the active properties or due to its intelligent properties can monitor the changes in food. In theory, the legislation about the packaging of food and edible packaging was described. The substances for edible films preparation and additives, which can improve the properties of the edible films, were described too. In this part, the undesirable microorganisms occur in food and the chapters about active and intelligent properties of the edible films were summarized. The main aim of the thesis was the practical preparation of edible packaging/films made from furcellaran, gelatin hydrolysate with the addition of water dried or fresh rosemary extracts in concentrations 5 %, 10 %, and 20 %. In the experimental part, the physical analysis was done – textural parameters such as tensile strength and elongation at break, water content, and thickness. In the chemical analysis the total polyphenols content, determination of polyphenols by HPLC, antioxidant activity, optical properties and antimicrobial activity of the prepared edible films were done. There were found out, that the total polyphenols content and antioxidant activity were the highest in the 20%DR (TPC: 6,79 ± 0,06 mg gallic acid/g; DPPH: 87,84 ± 0,07 %). Also, the 20%DR and 20%FR changed color in different pH (3 and 12). The antimicrobial activity was negative. The thesis showed that the addition of natural extracts to edible films can increase the polyphenols content and they can also work as the UV protector.
|
|
|
Carbon sorbents for biologically active substances
Lanžhotská, Aneta ; Sedláček, Petr (referee) ; Pekař, Miloslav (advisor)
This Bachelor thesis deals with the general characteristics of lignite and its definitions as a material system. Lignite represents geologically the youngest type of coal, and belongs to kaustobiolites, which are masses with varying degrees of carbonification of the original phytomass. The degree of carbonification is roughly between peat and brown coal. Particular attention was paid to the application of lignite as a cheaper and more versatile sorbent to replace activated carbon and for the use of sorption of biologically active substances in biotechnology. The specific structure and composition give the lignite the natural sorption capability. In model experiments, polyphenols were used as significant microbial inhibitors for which lignite had a high sorption and for glucose, which lignite practically did not absorb. A model experiment was carried out with a hydrolyzate of a corn biomass, where the lignite showed optimal sorption.
|
|
|
Polyphenols in nutritions and their effect on DNA
Osorio, Juan ; Černayová, Diana (referee) ; Brázda, Václav (advisor)
Epidemiologické studie prokázaly vliv konzumace rostlinných potravin v prevenci široké škály nemocí. Přírodní antioxidanty přítomné v těchto potravinách, mezi nimiž jsou velmi důležité polyfenoly, mohou být zodpovědné za tuto činnost podporující zdraví. Cílem bakalářské práce je ukázat interakci určitých polyfenolů s genetickým materiálem prostřednictvím různých signálních mechanismů, zejména pokud jde o stabilizaci nekanonické struktury DNA G-kvadruplex a poukázat tak na nejselektivnější látku pro inhibici biochemických procesy. Dále práce obsahuje podrobné informace, které mohou pomoci pochopit, jak mohou polyfenolové sloučeniny interagovat s DNA prostřednictvím epigenetických mechanismů a G4 struktur, a které faktory mohou ovlivnit jejich účinnost. Různé experimenty, biologickým a experimentálním opakováním, byly použity k potvrzení interakce mezi sloučeninami a DNA.
|
|
|
Study of natural substances of ginger
Dobiáš, Vojtěch ; Vespalcová, Milena (referee) ; Veselá, Mária (advisor)
The aim of this study was to determine the quantity of natural substances in ginger. Extracts from organic ginger tea and ginger rhizome were prepared using three different solvents. Antioxidant activity and the content of polyphenols and flavonoids were determined spectrophotometrically. Effects on bacterial growth of the extracts were studied against bacteria Bacillus cereus and Serratia marcescens by agar well diffusion assay. The obtained data showed, that there is a significant amount of difference between the contents of studied compounds in the two extract samples. The highest amount of polyphenols was found in ginger tea with concentration of 0,481 mgml-1, compared to 0,078 mgml-1 found in the ginger rhizome. The tea showed a greater antioxidant activity than the rhizome. Bacterial growth was slightly inhibited only by water extracts of the tea and this was only observed against Bacillus cereus.
|
|
|
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.
|
guest ::
