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Isolation of active compounds from algae and their application in cosmetic products
Nováková, Laura ; Byrtusová, Dana (referee) ; Skoumalová, Petra (advisor)
The bachelor thesis is dedicated to the study of active substances and antioxidant effects of cultivated microalgae. We compared the results with a commercial alga that is freely available. In the theoretical part we focused on description of algal metabolites in cosmetics and a brief description of the methods used in their testing. In the experimental part there were analyzed three types of extracts (aqueous, alcohol and oil) from 4 species of algae. It is mainly the content of polyphenols, flavonoids and antioxidant activity that is determined. According to the results, the highest content of active substances was found in oil extracts. All extracts were encapsulated into liposomes. The average size of the nanoparticles was in range of 200 nm to 300 nm. The particles were stable enough also for long-term stability. The largest decrease was observed in the oil extract of the cultivated algae Chlorella vulgaris. The cytotoxicity of oil extracts was realized by MTT test on human cell cultures HaCaT. Finally, we concluded that the prepared liposomal particles could be used for anti-aging cosmetics.
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Influence of Storage Conditions on Metabolic Profile of Apples
Duroňová, Kateřina ; Vávrová, Milada (referee) ; Kráčmar, Stanislav (referee) ; Márová, Ivana (advisor)
The goal of presented dissertation has been complex analysis of changes in content of fatty acids, enzymatic and low-molecular antioxidants in apples and related evaluation of perception of originators of storage diseases for apples stored in various conditions. Main part of the work has been dedicated to study of the impact of storage of apples in modified atmosphere with reduced amount of oxygen and in reference “normal” atmosphere for six months. Next part of the work has been dedicated to study how apple storage in common, consumer affordable, conditions (storage in a cellar, in a refrigerator, and in room temperature) affects content of low-molecular antioxidants. For testing has been selected apple kinds Jonagored, Golden Delicious, Idared, Šampion, and Granny Smith. Within the scope of this work has been optimized the method for determination of fatty acids in plant material with higher content of wax. The measured values imply the apples are valuable source of many important nutrition substances like vitamins, provitamins and antioxidants. During the storage process these substances exhibit considerable protective function. Long-term storage, mainly in the atmosphere with reduced amount of oxygen (FAN), enables preservation of majority of these important nutrition substances depending on the kind of apple and conditions of storage. Freezing process is conservative to apples (mainly in the presence of protective substances), while in the process of drying the values of all monitored antioxidants decrease depending on temperature and conditions of drying. Upon the choice of the storage method one must consider nutrition, sensoric characteristic and consumer demands.
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Kyselina kávová jako nový fluorescenční marker kvality nápojů
Vodová, Veronika
The work was focused on the study of the photochemical behaviour of caffeic acid (KK) with focus on the evaluation of quality of beverages. This organic acid is found in various beverages of natural origin, such as grape wines, juices, or teas. KK shows a very interesting photochemical behaviour, which is influenced by the environment in which it is found. If the quality of drinks changes, for example from the point of view of punching, the concentration of KK and the reaction conditions will naturally change as well. If such samples are exposed to UV radiation (starting photochemical reactions) and then is recorded fluorescence, which can be used to distinguish the sample from each other. Due to the complexity of this issue, this work is divided into two parts. The first (overview) part of this work contains important information about KK from different perspectives (occurrence, metabolism, effects etc.). The second (practical) part this work focused on fluorescence monitoring of KK standard under different conditions after UV irradiation (effect of UV exposure time, effect of pH of the environment and effect of phosphate buffer concentration). Based on the results, it was clearly demonstrated that the fluorescence properties of KK (photochemical behaviour) are strictly dependent on the pH, UV radiation time, the concentration of KK used and the chemical composition of the drink. These results suggest that KK can be considered as a fluorescent marker of beverage quality. To test this hypothesis will need to be analysed a larger number of real samples and statistically evaluated.
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Chlorofyl a jeho význam pro zdraví
Hübnerová, Amálie
This bachelor thesis deals with chlorophyll and its importance for health. It focuses on describing the structure of chlorophyll as a plant pigment and the organelle chlo-roplast in which it located. Properties that are important for photosynthesis are described here. Its application in the food industry and effect on health as an antio-xidant or use in the prevention of chronic diseases such as cancer, Diabetes mellitus and Trimethylaminuria have been investigated. Chlorophyll has even been found to act as a new antiviral against COVID-19.
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Fosfolipidy v potravinách
Zahradníková, Nikol
The main goal of this thesis is to highlight the benefits of phospholipids, which are currently underappreciated. The first part is devoted to a description of their basic characteristics, digestion and biological importance in living organism. Phospholipids differ in the benefits they provide to our organism. The next part focuses on the importance of their use in the food industry. In this sector, phospholipids are widely used as additives. Further, the work highlights the main sources and manufacturing animal and vegetable lecithin. Produced lecithin then undergoes a changing process of its chemical structure called modification. The modified lecithins produced this way have various applications in food. Subsequently, the thesis deals with methods for the determination of phospholipids in food. Specifically described is the most popular method for detection phospholipids in egg yolk and soy, HPLC-ELSD. The conclusion is devoted to the explanation of phospholipid fortification and functional foods. The increasing popularity of nanoliposomes in the food industry and the legislative requirements for lecithin are also mentioned.
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The impact of benzoic acids, metabolites of flavonoids, on the iron-catalysed Fenton reaction
Klenovičová, Alexandra ; Mladěnka, Přemysl (advisor) ; Karlíčková, Jana (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Alexandra Klenovičová Supervisor: Prof. Přemysl Mladěnka, PharmDr., Ph.D. Consultant: Zuzana Lomozová, Ph.D. Title of diploma thesis: The impact of benzoic acids, metabolites of flavonoids, on the iron-catalysed Fenton reaction Oxidative stress is a condition in which there is an increased production of free radicals that exceeds endogenous antioxidant activity and leads to damage of biomolecules. A number of human diseases are associated with oxidative stress. However the use of antioxidants has failed in clinical trials, but it is possible that the fact that antioxidants may preferentially exhibit prooxidant activity under elevated antioxidant concentrations in various pathophysiological conditions. Various in vitro and epidemiological studies have confirmed the presence of antioxidant and prooxidant properties in flavonoids. However, on the basis of their pharmacokinetics, it is evident that after their oral intake, significant metabolism in the colon takes place, where small phenolic substances are formed in interaction with the intestinal microflora. There is a possibility that the antioxidant and harmful prooxidant properties that have been attributed to flavonoids are in fact a...
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The influence of benzoic acids (metabolites of flavonoids) on the copper-triggered Fenton reaction and hemolysis
Harčárová, Patrícia ; Lomozová, Zuzana (advisor) ; Karlíčková, Jana (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacognosis and Pharmaceutical Botany Student: Patrícia Harčárová Supervisor: Zuzana Lomozová, MSc., Ph.D. Title of diploma thesis: Effect of benzoic acids (flavonoid metabolites) on copper catalyzed Fenton reaction and hemolysis Keywords: flavonoids, benzoic acids, copper, Fenton reaction, hemolysis Copper is a biogenic trace element that is present in several enzymes and proteins in the human body. The ability of copper to change its oxidation state is essential for its biological functions and enables enzymatic redox reactions in the organism. Homeostasis of copper is strictly regulated in the human body as its disruption can lead to the toxic effects of copper. Flavonoids are secondary plant metabolites that are a common part of our diet and their consumption has positive effects on our bodies. However, under certain conditions, they can also have a pro-oxidative effect, which is related to their ability to reduce transition metal ions. Flavonoids are massively metabolized in the human body before reaching systemic circulation into small phenolic substances including benzoic acids. Seven benzoic acid derivatives were tested as part of this thesis. Their influence on the production of hydroxyl radicals arising during the...
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Bacterial cellulose based facial mask with antioxidant property
Borová, Šárka ; Hoová, Julie (referee) ; Kovalčík, Adriána (advisor)
This final thesis deals with the preparation of a cosmetic facial mask based on bacterial cellulose. The motivation of this work was to prepare a cosmetic mask with antioxidant properties. To obtain bioactive substances with antioxidant activity, extracts from the rosehip fruits (Rosa Canina L.) with different weight dosages of rosehips and different preservatives were prepared. These rosehip extracts were subjected to spectrophotometric methods, thanks to which the total contents of polyphenols, flavonoids and total antioxidant activity were determined. It was proven that the content of the determined substances increases with the proportion of weighted rose hips and the highest contents of antioxidant substances were measured in extracts with a weight of 25 g of rose hips. Subsequently, these selected extracts were modified into several samples of bacterial cellulose. After the modification of the substances, it was demonstrated that bacterial cellulose is a suitable material for absorbing bioactive substances into the structure of individual analyzed samples. It was found that bacterial celluloses in the form of hydrogel and lyophilized bacterial cellulose were able to absorb the largest amount, of bioactive substances with antioxidant properties. On the other hand, the samples of dry bacterial cellulose and bacterial cellulose with an alginate component absorbed active substances the least. Furthermore, analysis using a Visioscope device revealed that the facial cosmetic mask based on bacterial cellulose in the form of hydrogel could potentially have not only antioxidant but also hydrating effects on the skin.
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Vliv přírodních aditiv na prodloužení skladovatelnosti chlazených paštik z kapra obecného (Cyprinus carpio)
TUNYS, Ondřej
This diploma thesis evaluates the effects of cranberry, garlic and onion extract on microbiological quality, sensory attributes and oxidative effect of common carp (Cyprinus carpio) pâtés. The evaluation is expressed in comparison with the control sample (no additive). Individual analyzes took place in different terms depending on the analysis performed (usually on day 0, then after 1, 2, 3 and 6 months of storage). Microbiological analysis showed values in the range of 1.71 - 2.05; 1.73 - 2.23; 1.43 - 2.14; 1.36 - 2.21 log CFU*g-1 at individual terms (0, 1, 2 and 6 months). The accessible limit for freshwater fish consumption (7 log CFU*g-1) was not exceeded for any of the samples throughout the testing period. Onion extract reached the best values in microbiological analysis. However the best results in almost all sensory attributes (odour, taste, aftertaste, consistency, color, overall acceptability) were achieved by pate with garlic and cranberry. TBARS analysis evaluating lipid oxidation also proved inhibition of oxidation processes. All the results of this research showed that natural additives have good antioxidant effects extending the shelf life of carp pâtés with suitable storage (preservation and cooling at 4 +- 1 °C) for up to 6 months.
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Testing antioxidant properties of selected acetylcholinesterase inhibitors
Kucková, Jana ; Vopršalová, Marie (advisor) ; Herink, Josef (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Jana Kucková Supervisor: PharmDr. Marie Vopršalová, CSc. Title of diploma thesis: Testing antioxidant properties of selected acetylcholinesterase inhibitors Very widespread Alzheimer's disease is typical by a complex pathology. Its causality is not clearly understood. There is increasing discussion due to the negative impact of free radicals on this disease formation. There are testing new substances that have also antioxidant properties, in addition to their classical effects. The aim of this diploma thesis is spectrophotometric testing of antioxidant properties of selected acetylcholinesterase inhibitors. It is based on DPPH test where the presence of antioxidants with antiradical activity causes the reduction of the color stable 2,2-diphenyl-1- picrylhydrazyl (DPPH) radical to a colorless molecule. The principle of the method is the measurement of decrease in absorbance (decolorization) of selected substances that are directly proportional to the antioxidant (antiradical) efficacy of the analyzed inhibitors. It focuses on twelve samples, Phenothiazine, which is the leader structure of new inhibitors synthesis, and two standards. Antioxidant activity is expressed as the effective...
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