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Encapsulation of active substances and possibilities of their application in anti-aging products
Horváthová, Iveta ; Němcová, Andrea (referee) ; Skoumalová, Petra (advisor)
The aims of this thesis were encapsulation of selected active substances and their possible application in cosmetic products with anti-aging effects. 6 kinds of active substances were studied – lipophilic vitamin E and vitamin A, hydrophilic vitamin B1 and vitamin B2, and phenolic compounds ferulic acid and chlorogenic acid. In theoretocal part, the general characteristics of active compounds and their use are described. It also includes the description of used methods. Practical part was focused on characterisation of active compounds from the perspective of antioxidant activity and encapsulation into liposomes from soy and sunflower lecithin. Encapsulation effectivity, size, stability and long-term stability of liposomes after four weeks were determined. The most suitable liposomes with active compounds were also tested for safety on human skin cells using the MTT test of cytotoxicity on keratinocytes HaCaT. Furthernore, 3 types of cosmetic products were prepared – day cream, night cream and skin serum. Each kind of cosmetic product was devided into 4 types – the product without any active compounds, the product containing free active compounds, the product with liposomes with active compouds and the product containing empty liposomes. As active compounds all our tested substances were used. Final products were tested 14 days on 15 female volunteers. Before and after products usage parametres of their skin were measured to analyze effect of products on skin rejuvenation. Volunteers were also rating sensory analysis of cosmetic products. The part of this thesis was also creating an online questionnaire about anti-aging cosmetics for publicity to find out the popularity of this kind of cosmetics.
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Developement and optimalization of methods for extraction of selected compounds from Hypericum perforatum
Chytil, Dalibor ; Štursa, Václav (referee) ; Pořízka, Jaromír (advisor)
Bachelor's thesis deals with the optimization of processes for extraction of phenolic compounds from St. John´s Wort (Hypericum perforatum). The theoretical part of the work focuses on characterization of this herb, its botanical classification, traditional use, chemical composition and curative effects. Increased attention is further devoted to a theory of preparation of samples for extraction of phenolic compounds and suitable techniques for extraction and characterization of phenolic compounds from extracts of St. John´s Wort. The experimental part of the thesis deals with application of theoretical knowledge. When optimizing the emphasis was on influence of solvent (water acified to pH 4, pH 5, pH 6), influence of extraction technique (ultrasound extraction, subcritical water extraction, maceration) and influence of extraction period (10, 20, 30 min). Extracts were subjected to determination of selected parameters (total phenolic content, total flavonoid content, antioxidant activity) in leaves of St John´s Wort harvested in June 2016 using UV-VIS spectroscopy. The used extraction techniques are significantly different from each other.
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Optimization of echinacea drops production technology
Boberová, Jana ; Vespalcová, Milena (referee) ; Zemanová, Jana (advisor)
This diploma thesis deals with the production of herbal drops from Echinacea and the determination of the content of selected active substances. In the theoretical part, the taxonomic classification of echinacea, its botanical characteristics and growing conditions are mentioned. The history of cultivation and uses of this plant are also mentioned. An important chapter of the theoretical part is the chemical composition of the plant and differences in composition between individual cultivars of Echinacea. Methods for obtaining active substances and their determination are also mentioned. The last chapter is devoted to the technology of production of echinacea drops. In the experimental part, the extraction was optimized for dried flowers and roots of E. purpurea. The following extraction system was determined for the flowers: 40% ethanol, time 6 hours, weight to solvent ratio 1:10 and room temperature. For the roots, 20% ethanol and a time of 24 hours, a ratio of 1:10 and room temperature were evaluated as the best conditions. Furthermore, the best extracts were prepared, in which the content of total phenolic substances was set at 0.799-0.839 mg/ml, then the antioxidant activity was determined in the range from 116 to 242 µg T/ml, and finally the analysis of aromatic substances was performed by HS-SPME-GC-MS. Two commercial samples were also tested to compare the prepared extracts.
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Antimicrobial effect of plant extracts
Konderla, Patrik ; Vespalcová, Milena (referee) ; Veselá, Mária (advisor)
The purpose of this bachelor thesis was to research the possible antimicrobial activity of various extracts of rosehip tea and also determine the antioxidant activity and the concentration of biologically active compounds (polyphenols and flavonoids) in these tea. Teoretical part describes basic information about plant Rosa canina and chemical composition of rosehips, summary of the natural biologically active compounds and general classification of tea. The practical part is focused on detection of antimicrobial activity of tea extracts against bacterial strains Serratia marcescens and Bacillus subtilis as well as spectrophotometrical determination of concentration polyphenols, flavonoids and overall antioxidant activity of these extracts. From the results flow the testing aqueous extracts rosehips tea analysed antimicrobial effects. Also was found, that these extracts has high content of polyphenols and flavonoids.
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Analysis of phenolics in different kinds of coffee
Jašková, Martina ; Halienová, Andrea (referee) ; Márová, Ivana (advisor)
The aim of this bachelor thesis was examining the quantity of biologically significant substances in selected types of roasted ground coffee, instant coffee and coffee extract. The particular kinds of coffee differed in technological processing, degree of roasting and composition. In the practical part total phenolics and flavonoids by using spectrophotometry methods. The total antioxidant activity in the individual coffee extracts was determined by ABTS method. Qualitative and quantitative analysis of some individual antioxidants and caffeine was performed using RP-HLPC with spectrophotometric detection. As a part of the work sensory analysis of all coffee samples was realized and consumer questionnaires were completed.
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Analysis of biologically active substances in some cereal products
Valentová, Radka ; Starečková, Terezie (referee) ; Márová, Ivana (advisor)
Presented bachelor thesis is focused on study of biologically active substances in cereal products. In theoretical part over view of cereal active substances, predominantly phenolic compounds were introduced. In practical part 15 kinds of cereal products were analyzed. In these materials some group parameters - total phenolics, total flavonoids and total antioxidant activity were measured by spectrophotometry. RP-HPLC/UV-VIS method was performed for analysis of selected individual flavonids. The highest content of phenolic compounds was measured in cereals containing fruits (raspberries, blueberries, tropical and red fruit), cacao, crusty fruits (hazel nuts, sunflower seeds) and buckwheat. All cereal products contain catechine, epicatechine, catechin gallate, epicatechin gallate, chlorogenic and ferulic acid. As a part of bachelor thesis simple sensory analysis was performed and consumer questionnaires were evaluated.
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Study of rose hip bioactive compounds
Konderla, Patrik ; Skoumalová, Petra (referee) ; Veselá, Mária (advisor)
Purpose of this thesis was research the content of biologically active substances in herbal rosehip extracts and also determination of antimicrobial and antioxidant activity of these extracts. Teoretical part describes informations about Rosa canina L., detailed specification of biologically active substances, specification of antioxidation and overview of methods determine antioxidant compound and antimicrobial activity. In the practical part was by combination of different solvents, procedures and herbal materials, made 21 extracts of Rosa canina L.. From measuring of these extracts, was made extraction curves and also was determined antimicrobial efficiency against bacterial strains Serratia marcescesns, Bacillus subtilis, Bacillus cereus and Micrococcus luteus. Results shows, that also all extracts has some antimicrobial activity, but only against microorganisms Micrococcus luteus and Bacillus cereus. Also was found that bud extracts contains more bioactive compounds soluble in ethanol, meanwhile rose hip extracts contains more bioactive compounds soluble in water.
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Modern Approaches in Qualitative Aspects of Foods Assessment
Tobolková, Blanka ; Omelka, Ladislav (referee) ; Rapta, Peter (referee) ; Buňka, František (referee) ; Polovka, Martin (advisor)
Antioxidant properties and some other characteristics of selected organic and conventional products (wine, spelt flours) were evaluated in view of their potential utilization as markers suitable for food unambiguous differentiation according to the affiliation to production system. Beside these, study of fruit juices stability during storage in dependence on different technological procedures of juice processing was performed. In both cases, combination of dominantly EPR and UV/VIS spectroscopy but also other methods (e.g., HPLC, AAS, electrophoresis) was applied to evaluate the stability and antioxidant properties of selected samples. Statistical methods, especially methods of multivariate statistics were used to assess the influence of production and technological-processing operations on antioxidant status of foods and their selected characteristics. Qualitative analysis of Slovak and foreign organic and conventional wines proved that their antioxidant properties are influenced by production system, vintage and variety. On the basis of statistical analysis, descriptors of AAE, kTEMPOL and %RS were selected as the most powerful markers for Slovak organic and conventional wines discrimination. The discrimination of white and red organic and conventional wines possessed 100% and 95.2% correctness, respectively. High correctness of differentiation of Slovak and foreign wines was also achieved. Monitored descriptors of antioxidant activity of spelt flours varied in dependence on season, origin, variety, production system and depend also on way of spelt treatment, although this effect is not so significant. It was also confirmed that the type of extraction agent substantially affects the composition of extracts including polyphenols and flavonoids concentration, affecting thus also their antioxidant activity. Mixture of 50% ethanol/water was selected as the most promising extraction system. Although the results of individual spectroscopic assays revealed high variability and often ambiguous trends, the differences found were sufficient for successful differentiation of both wines and spelt flour samples according to the selected criteria by multivariate statistical processing of the data. Influence of changes in technological procedures of fruit juice processing (nitrogen atmosphere application, utilization of caps with oxygen scavengers) on radical-scavenging properties of 100% pineapples juices with pieces of pineapple and 100% orange juices with pulp was assessed as well. Results obtained proved that antioxidant activity of juices varied in dependence on storage conditions (temperature, storage time, light exposure) and depends also on origin, variety and quality of fruit used. However, the application of nitrogen atmosphere and active packaging materials is not sufficient enough to eliminate the oxidation reactions in juices, but changes in antioxidant activity are better predictable. It can be concluded that EPR spectroscopy could be effectively applied for wines and spelt flours differentiation according to the way of production and to assess the stability of food products, either alone or in combination of UV/VIS spectroscopy and the other methods, utilizing multivariate statistics for processing of experimental data.
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Use of rare oils in cosmetics
Pilipenco, Alina ; Szotkowski, Martin (referee) ; Němcová, Andrea (advisor)
The purpose of this bachelor thesis was to research rare oils. The oils from selected plants (poppy, cannabis, thistle) is characterized by the content of active phenolic compounds, fatty acid composition, antioxidant and antimicrobial effects. First part of the thesis is a literary research on a given topic, which contains the following parts: the universal chemical composition of vegetable oils, the characteristics and effects of selected oils and the ways of their obtaining for cosmetic purposes. The experimental part is focused primarily on the basic analysis of selected oil components and the preparation of the shower oil based on the obtained results. In conclusion are presented an overview of all the properties of selected oils, their practical use and assessment of their application in cosmetics.
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Antioxidant activity of green tea extracts
Šedý, Michal ; Vítová, Eva (referee) ; Veselá, Mária (advisor)
This bachelor thesis focuses on antioxidant and biological active compounds present in green tea extracts. Green tea is a rich source of antioxidants and it has been considered a medicinal beverage in the past. Series of compounds contained in green tea extracts exhibits strong antioxidant effects. The theoretical part of this thesis deals with the history and production process of tea. It also focuses on the description of the most abundant antioxidant and bioactive substances in tea. Three green tea samples from the retail chain were selected in the experimental section, which were further analysed by selected UV-VIS spectrometry methods and then compared.
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