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Possibilities of preparation combined drinks from selected fruits
Zábranská, Miroslava ; Vránová, Dana (referee) ; Vespalcová, Milena (advisor)
This thesis deals with the preparation of the combined alcoholic beverages based on wine and fruit juices. The fruit juices were obtained from the selected fruits as honeysuckle, mulberry, dogwood, rose hips, elderberry, buckthorn and aronia. Some chemical properties e. g. total fenolics, total anthocyanins, vitamin C and sacharides were determined for characterization of the mentioned juices. As well as chemical parameter of juices, the same chemical parameters were determined on wine. There were prepared three sets of combined beverages from wine and juices. The two best evaluated beverages were chosen on the basis of their sensory evaluation. In the end, the same chemical properties were determined in both particular juices and resulting beverages.
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Incorporation of low molecular weight and high molecular weight substances into vesicular systems
Geistová, Karolína ; Smilek, Jiří (referee) ; Mravec, Filip (advisor)
This master´s thesis deals with the study of the incorporation of low and high molecular weight substances into liposomal systems. The aim of the work was to determine the encapsulation efficiency (EE) of the active substance and the influence of individual components of the liposomal system on EE. Liposomes were prepared from dipalmitoylphosphatidylcholine. They were stabilized by cholesteroland and phosphatidic acid was added to give a negative charge. Stealth properties gain the binding of polyethylene glycol and other trimethyl chitosan we enabled the entry of liposomes into the bloodstream by the paracellular pathway. Vitamin C and the enzyme bromelain were used for incorporation into liposomes. UV-VIS spectrophotometry was used to determine the encapsulation efficiency of liposomes prepared by combining the individual components. It has been suggested that vitamin C and the enzyme can be incorporated into liposomes, but an enzyme with a higher EE. Furthermore, phosphatidic acid and trimethyl chitosan have been found to affect EE, which increases the EE of vitamin C and decreases the EE of the enzyme.
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Study of plasma effects on quinine solutions
Procházková, Michaela ; Dzik, Petr (referee) ; Kozáková, Zdenka (advisor)
This diploma thesis focuses on quinine solutions and quality of these solutions after applying plasma discharge. These electric discharges can be used to destroy some substances from the water. The theoretical part is focused on description of electric discharges in liquids and on the properties of quinine. In the experimental part, the properties of quinine solutions containing different electrolytes were analysed by UV-VIS spectrophotometer and fluorescence spectroscopy. Two different types of configurations of plasma discharges in liquids were used. Solutions were compared on the base of different concentration of quinine, different electrolytes, different configurations of plasma discharges and pH values of the solutions. Furthermore, the experimental work focuses on quinine solutions with the sodium nitrate. The time instability of the solutions was analysed. Also, the influence of the solution age and different types of the plasma discharge on the excitation and emission spectra of quinine were investigated.
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Investigation of the effect of creatine in combination with magnesium and vitamin C on the performance of the individual person
Vlasák, Jan ; Němcová, Andrea (referee) ; Diviš, Pavel (advisor)
Creatine is nitrogen-containing organic acid which naturally occurs in the human body. The aim of this work was to determine the optimal dose of creatine in combination with vitamin C and magnesium for male respondents aged 18-26 years. They were divided into two groups differing in the creatine dosage. Group 1 took smaller dose of creatine (3 g per day) and group 2 higher dose of creatine (10 g per day). Both groups took both magnesium and vitamin C at constant doses throughout the study. The effects of significantly different dose of creatine in the individual groups were compared with each other in terms of the performance of individuals in the powerlifting, the anthropological changes and the overal metabolism of the intakes. In all disciplines of powerlifting, group 1 recorded higher average weight gains, which were not found to be statistically significant at a significance level of alpha 0,05. Anthropological changes were measured using the InBody 160 and a diagnostic measuring tape. In both cases, group 1 recorded better results than group 2, but these results were not statistically significant at a significance level of alpha 0,05. The total metabolism of the accepted dietary supplements was investigated through analytical methods. The urine of each respondent was regularly collected and subsequently analyzed during the research. Determination of creatinine, a creatine waste product, was performed by UV-VIS spectrophotometry using the Jaffe reaction. Vitamin C was analyzed by RP-HPLC. Magnesium was determined by the ICP-OES method. After creatine suplemantion of 3 per day, group 1 showed a slight increase in creatinine in the urine, but still in the physiological range. At the significance level alpha 0,05 there was no statistically significant difference. Group 2 showed an increase above the physiological limit which was already a statistically significant difference. Overall, creatine supplementation of 3 g per day has been found as a sufficient intake of creatine needed to build up muscle mass, increase energy metabolism and overall physical performance. The metabolization itself works very well and within the physiological values.
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Optical properties of protective emulsions
Valasová, Denisa ; Veselý, Michal (referee) ; Zmeškal, Oldřich (advisor)
This bachelor´s thesis is aimed to the study of optical properties of protective commercially available emulsions. Chosen emulsions should be responsible for sun protection. They also may be used in cosmetic industry. In the beginning of the thesis, there are defined theoretical features of emulsions and their interaction with UV radiation. Methods which are used to describe optical properties could be found in this section too. The optical properties were measured in thin layer films, in order to simulate emulsions applied on the human skin. UV-VIS spectrophotometry was mainly used to study the optical properties. The obtained results could serve, purely hypothetically, like sun protective tests of chosen emulsions.
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Releasing of the solubilized substances from the phase-separated hydrogels
Havlíková, Martina ; Krouská, Jitka (referee) ; Mravec, Filip (advisor)
This bachelor thesis is focused on releasing of the solubilized substances from the phase separeted hydrogels. The aim of this work is to determine the solubilization capacity of these hydrogels. Preparation of them were based on interaction between hyaluronan and cationic surfactant carbethopendecinium bromide. Hydrogels were prepared by two possible ways, „wet“ and „dry way“. For solubilization experiments were used fluorescein and acridine orange as fluorescent probes. Primarily UV-VIS spectrophotometry was used to determine if these probes are released form hydrogel or not. Hydrogels were monitored after 24, 48 and 72 hours from their preparation. But this method proved to be inappropriate and inaccurate, because of cloudy supernatants over the hydrogels and also because of very low concentrations of fluorescent probe in this solution. For these reasons instead of this metod was used method, which is based on fluorescence. The instrument is called MicroTime 200. It´s very accurate method and results of this are considered like relevant. It was proved that fluorescein as a negatively charged molecule is released less than acridine orange.
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Influence of dispersion parameters on formation of vesicular systems
Vajcíková, Katarína ; Smilek, Jiří (referee) ; Mravec, Filip (advisor)
The work describes a method for the preparation of catanionic vesicular systems using the method of ultrasonic dispersion in order to find the most suitable parameters for the preparation of a system with long–term physical stability. The parameters compared were the amplitude of the ultrasonic wave, the energy used for dispersion, and the volume of deionized water used to prepare a system consisting of the negatively charged surfactant sodium dodecyl sulfate and the positively charged surfactant hexadecyltrimethylammonium bromide. To increase stability and provide a positive charge, the surfactant dimethyldioctadecylammonium chloride was used and cholesterol was also added to increase stability. The individual systems were compared over time because of their size, zeta potential and turbidity of the solution. Particle size and polydispersity coefficient were measurement by the dynamic light scattering method. The zeta potential was determined by electrophoretic light scattering, and the turbidity was monitored by UV-VIS spectrophotometry based on the measurement of turbidity. The results present the most suitable parameters of ultrasonic dispersion using Bandelin SONOPULS UW 3200. The use of these parameters shows the emergence of systems with long–term physical stability, which means that they can be used for other applications.
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Srovnání antioxidačních vlastností a absorbce UV záření u extraktů vybraných bylin, Spiruliny a jejich směsí
Farinasso, Giulia
This study aimed to compare the antioxidant properties and UV radiation absorption of se-lected herbal extracts, blue-green algae spirulina extract and their mixtures. Extracts were ob-tained by ultrasound assisted extraction. The total polyphenol (TPC) and flavonoid contents (TFC) were determined, and the Trolox equivalent antioxidant capacity (TEAC) was meas-ured. The best antioxidant properties has been showed by C. officinalis individual extract and its mixture with spirulina. Additionally, the UV-absorbing substances at 355 nm were quanti-fied. The extracts from C. officinalis and S. nigra were further analysed for their rutin content by HPLC-DAD. The rutin content in S. nigra and C. officinalis extracts was found to be 1935,97 ± 98,39 μg.g-1 and 233,035 ± 8,839 μg.g-1 of dry weight of flos, respectively. The highest content of phenolic compounds was found in the S. nigra extract, and the highest total antioxidant capacity was determined for the C. officinalis extract. Pearson's correlation re-vealed that the overall antioxidant capacity and UV absorption results were significantly cor-related with the total phenolic compound content only for the elderflower extract. The syner-gistic effect of the herbs used in combination with spirulina was evaluated.
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Quantification of the stabilizing effects of cyclodextrins on volatile biocides using spectral methods
Konovalova, Olga ; Jindřich, Jindřich (advisor) ; Smrček, Stanislav (referee)
This bachelor's thesis deals with monitoring the stability of chlorine dioxide of native and methylated cyclodextrins in the presence of hydrogenating agents. It is believed that using cyclodextrins and carboxymethylcellulose can improve the stability of chlorine dioxide and slow its release from the solution. UV spectroscopy was used to monitor any changes in absorbance over time and to determine the concentration of chlorine dioxide in the solution. When the rate of chlorine dioxide loss from solution was monitored, it was found that the presence of native and permethylated cyclodextrins slowed the loss of chlorine dioxide from solution, with the slowest decomposition observed in the presence of permethylated cyclodextrin. The addition of carboxymethylcellulose to the chlorine dioxide solution slows the rate of chlorine dioxide loss from the open vial the most, by almost three times, compared to ClO2 itself. This study's results can help optimize chlorine dioxide product formulation for various applications and contribute to the development of more stable and effective chlorine dioxide- based products that can be used to control or eliminate harmful microorganisms in different environments. Key words: chlorine dioxide, CDS, cyclodextrins, carboxymethylcellulose, biocides, UV-Vis...
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The fate of phosphorus in root wastewater treatment plants
Veselá, Klára ; Sobotníková, Jana (advisor) ; Nováková, Eliška (referee)
This bachelor's thesis deals with the determination of phosphorus in constructed wetlands. Phosphorus in wastewater must be eliminated effectively because there is a government regulation that permits maximal permissible concentration of phosphorus on the exit of wastewater treatment plants. Increased concentration in water leads to eutrophication, which causes the death of aquatic animals and plants. The aim of this bachelor's thesis is the validation of an easy and functional method for the determination of phosphorus in the water matrix. This method uses a complex with malachite green. The next aim was the determination of phosphate in the samples from model constructed wetlands. It's possible to make conclusions about the efficiency of model constructed wetlands out of this. For the determination UV-VIS spectrophotometry was used. The measured absorbance was recalculated to a concentration of phosphorus and after that to the concentration of phosphate. During the validation calibration, accuracy measurement, repeatability measurement, and measurement of absorbance dependence on time were performed. Sensitivity (by comparing the malachite green method with the normed method using phosphomolybdate blue), linearity, trueness, robustness, the limit of detection, and the limit of quantification were...
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