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Uses of active compounds from honey in cosmetic products
Balášová, Patricie ; Langová, Denisa (referee) ; Skoumalová, Petra (advisor)
The bachelor thesis was focused on the preparation and characterization of extracts and liposomes with active substances from chosen types of honey with the aim to apply these extracts to the cosmetic products. The extraction of active substances from chosen material was optimized during the work. As the most suitable organic solvent for extraction was chosen diethyl ether. All the extracts were tested on the content of total polyphenols, sugars and antioxidation activity. The final samples were also tested on the content of flavonoids. Extracts were encapsulated to the liposomes, which were tested especially for their antioxidation activity, size and stability. Then, extracts and liposome particles were applied to the cosmetic products. Cosmetic creams and gels were prepared and tested for antioxidation activity and antimicrobial activity against the strains Serattia marcescens and Micrococcus luteus. Antimicrobial activity of gels was proved especially against the strain of grampositive bacterias – Micrococcus luteus. From this point of view another one testing strain was chosen – Propionibacterium acnes. Finally, the chosen liposomes were tested for their contact with human cells, immortalized keratinocytes HaCat. No cytotoxic effect was observed and tested materials can be applied to cosmetics against acne.
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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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Complex characterisation of medical herbs and study of their utilization in food industry as a source of functional components
Burdějová, Lenka ; Kráčmar, Stanislav (referee) ; Šilhár, Stanislav (referee) ; Polovka, Martin (advisor)
Presented thesis deals with the complex characterization of extracts from medical plants using spectroscopic and chromatographic techniques, with emphasis on the influence of solvent, post-harvest treatment of the sample, location and year of production on selected parameters. Part of the work is devoted to application of selected extracts from medical plants in suitable form into beverages. The thesis is divided into two parts. At the first part of the work combination of electron paramagnetic resonance, ultraviolet visible spectroscopy, liquid chromatography and inductively coupled plasma optical emission spectrometry was applied for characterization of aqueous, ethanol and dimethylsulfoxide extracts from 10 selected medical plants, which were collected from two different locations during two years (2015, 2016) and post-harvestly treated by two ways (freezing, drying). In total, 39 parameters were determinated: namely total phenolic compounds content, total flavonoids content, 14 specific phenolic compounds, colour characteristics in the CIE L*a*b* system (L *, a*, b *, C*, h°, BI), radical-quenching activity using the cation radical of the 2,2'-azino-bis- (3-ethylbenzothiazoline-6-sulfonic acid), antioxidant/pro-oxidant activity using the spin trapping technique in the presence of 5,5-dimethyl-1-pyrrolin-N-oxide (DMPO)/potassium peroxodisulphate and content of 15 minerals (Al, As, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, P, Pb, Zn). The results confirmed that the studied parameters of medical plants are influenced by the extraction system, post-harvest treatment of samples, year of production, origin of samples (locality) and species composition. It has been shown that the type of extraction solvent significantly affects the composition of the extracts. On the basis of these analyzes, for food application – the isolation of the main functional components (phenolic compounds, flavonoids) –50% ethanol, post harvest treatment by drying and samples of Mentha piperita, Melissa officinalis, Hypericum perforatum and Salvia officinalis were selected. The second part of the thesis was focused on the application of selected extracts of medical plants to beverages (syrups). The above mentioned plants, 25% ethanol instead of 50% ethanol (due to the limitation of the ethanol content in final raw material), were selected for the application. At first, extraction of medical plants was optimized. Suitable ratio of material and solvent (1:10), extraction time (8 h) and herb absorbency (50–62 %) were determined. The prepared extract after filtration was applied to the syrup concentrate in different ratios to produce one-species syrups and further sensorially tested to select the suitable recipe, the best flavour and basis for the production of two-species syrups. The mint syrup was the most tasty and generally the most acceptable one-species syrup, and sage syrup was selected as the basis for two-species syrups. Further, the most appropriate recipes of the two-species syrups were chosen, the most sensorially acceptable one was selected and further tested if it would be appropriate to colour them. Preferentially, it has been found that it is not necessary to colour two-species syrups. On the basis of the sensory analysis, it has been found that peppermint and sage-peppermint syrups were the most tasty and acceptable syrups, which could be, after further testing, produced industrially to enrich the food market.
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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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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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Evaluation of production parameters of selected beetroot cultivars
ŠINDELKOVÁ, Tereza
This bachelor thesis deals with the evaluation of the production parameters of selected assortment of salad beet varieties. A small-parcel experiment was established in six varieties (Alexis, Betina, Burpee's golden, D'Eggyte, Choggia, Karkulka). In the experiment the yield of boulevues from the area unit, the average bulk weight, the dry matter content, the carbohydrate content, the dry matter content in the dry matter (N x 6.25), the antioxidant activity and the color of the flour were determined.
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Studium zdraví prospěšných látek v semenech Vitis vinifera L.
Popluhárová, Lucie
This bachelor thesis with the topic Study of healthy substances in the seeds of Vitis vinifera L. has been written in the years 2015/2016 at the Department of viticulture and oenology at the Faculty of Horticulture at the Mendel University in Brno. The main purpose of this thesis was reading up some studies which are dealing with the composition of substances in the grape seeds. The attention was on the antioxidant compounds. There was described a composition of the grape (stem and berry, which contain skin, pulp, seeds) and distribution of the phenolics. Next there was described some studies which are focusing on antioxidant activity, polyphenolics, mineral substances, lipids and vitamins. Also there was described some methods which are using for analysis of grape seeds compounds (HPLC and TLC) and some methods using for measurement of antioxidant activity (DPPH, ABTS, FRAP and ORAC).
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Vliv přídavku technického konopí Cannabis sativa na antioxidační aktivitu u laboratorních potkanů
Urbánková, Lenka
This thesis studies an influence of hemp added to feed rations on the organism of tested animals. In this feeding experiment the effect of supplied hemp to weight increments and antioxidant activity was observed. The tested animals were rats of strain Wistar albino. The experiment was performed with 20 male rats which were divided into 4 groups. Two groups were fed with hemp mixture and other two with control mixture. During the experiment subjects were weighed once a week and weight gain and feed consumptions were recorded. Spectrofotometric method Folin-Ciocalteu for determinations of polyphenolic compounds was used. Antioxidant activity was measured for the individual samples of feed and liver tissues of tested animals. They were FRAP and TEAC method used. The results of measurement of antioxidant activity in liver tissue proved inconclusive for both methods. Demonstrable differences were found only in samples of feed. The processing was used ANOVA statistical method using the Scheffe test.
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Studium antioxidantů ve vybraných druzích koření pomocí moderních analytických metod
Lacková, Zuzana
A spice is a natural source of natural substances for humans, containing mainly phenols and flavonoids, which have exceptional antioxidant effects. Presented study described the most advanced analytical technique for evaluation of the presence and concentration of extracted natural antioxidants from ground spices (marjoram, pepper (sweet), black pepper, caraway seeds, anise, thyme, cinnamon, oregano). Subsequently, individual spices were analyzed on the overall efficiency of selected type of extraction. Further, the individual spices were examined on their total antioxidant activity using the DPPH, FRAP and total phenols assays.
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The antioxidant activity of St. John's wort explantate cultures
Vrabec, Rudolf ; Martin, Jan (advisor) ; Spilková, Jiřina (referee)
St. John's wort is a herbal medicine well known for its anti-depressant effect. It contains anthraquinone derivates, prenylated floroglucinols, tannins, hydroxycinnamic acids, and especially flavonoids, which have a wide range of biological effects on the body including antioxidant properties. Antioxidants are one of the possibilities to protect body from harmful influences of free radicals - highly reactive particles that damage biological structures. In this work, two methods (DPPH and superoxide radical) were used to determinate antioxidant activity of methanolic and aqueous extracts of dried St. John's wort - Hypericum Perforatum L. and its callus and suspension explant cultures. The results are processed into tables and graphs which compare the effectiveness of extracts to quench the radicals. EC50 for the methanolic extract was 0,064 mg/ml and for the aqueous extract 0,068 mg/ml. EC50 for the aqueous extract was 16,727 mg/ml, but unfortunatelly the other antioxidant activity values for EC50 were too low to evaluate. Determination of the content of flavonoids hyperoside and quercetin by high performance liquid chromatography shows that their highest content is in the drug extracts and that the explant cultures have negligible content of the flavonoids. There is no content of hypericin in all...
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