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Impact of honey enrichment on its antimicrobial activity by bioactive substances against Escherichia coli
ŠEBESTOVÁ, Lucie
The main aim of this bachelor's thesis is to determine the Minimum Inhibitory Concentration (MIC) and the Minimum Bactericidal Concentration (MBC) of both native honeys and honeys enriched with selected essential oils on the growth of Escherichia coli. In the theoretical part of the bachelor's thesis, bacteria Escherichia coli is briefly characterized, including its pathogenic strains and antibiotic resistance. Furthermore, honey is described, including its chemical composition and physiological effects. Additionally, essential oils are generally described, including their antimicrobial properties, along with a brief description of each selected oil. In the methodological part of the bachelor's thesis, procedures for preparing mediums, agar, inoculum, and the determination of their minimum inhibitory and bactericidal concentrations are described. MIC was measured spectrophotometrically in 96 well microtiter plates. MBC was determined by inoculation from the plate onto Mueller-Hinton agar followed by a 24hour incubation. A total of 3 native honeys were tested, which were then enriched with 8 selected essential oils. Essential oils with the addition of dimethyl sulfoxide (DMSO) were also tested. The results of the obtained data are statistically evaluated, graphically presented, and compared with scientific sources.
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Effect of honey fortification by selected bioactive substances on its antimicrobial activity against Staphylococcus aureus.
BOHDALOVÁ, Natálie
Staphylococcus aureus is a Gram-positive bacterium that can cause a wide range of infections, from mild skin infections to serious and life-threatening diseases. One of the main problems associated with this bacterium is still increasing to develop resistance to various types of antibiotics. Honey is a natural product made from the nectar of flowers collected by bees and stored in their combs. Honey has a wide range of ways it can be used for medicinal purposes, thanks to its beneficial effects. The main aim of this bachelor's thesis was to determine the minimum inhibitory and bactericidal concentrations of honeys, whether native or enriched with selected plant essential oils, or the plant essential oils themselves, on the growth of Staphylococcus aureus. The theoretical part focuses on basic information about the bacterium, the diseases it causes, and their treatment. Subsequently, the theoretical part delves into honey and its characteristics. Finally, plant essential oils and their properties are described. The methodological part of this thesis describes the individual tools and instruments that were used. The procedure for the preparation of honeys, plant essential oils and bacterial inoculum is also explained. Finally, the process of determining the minimum inhibitory and bactericidal concentrations is described. The determination of minimum inhibitory and bactericidal concentrations was carried out in 96-well microtiter plates, which were then measured spectrophotometrically. The results showed that the enrichment of honey with bioactive substances has in most cases positive properties on its antimicrobial activity against Staphylococcus aureus.
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Analysis of hazardous metals in rPET granulate
Souček, Elena ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
Production of polymer products has increased rapidly in recent decades. Especially in food industry as a packaging it gained a dominant position when it replaced previously used materials. Due to the direct risk for human health it is necessary to be careful and pay attention to their composition. It is also necessary to develop methods to properly recycle and reuse already used material, not only produce new products. This thesis deals with the study of the content of risk elements in PET regranulate. The samples were completely decomposed by microwave radiation in an environment of concentrated sulfuric and nitric acid. They were subsequently analyzed by atomic absorption spectrometry (AAS). Flame atomization technique (FAAS) was used to determine Sb and Zn and electrothermal atomization (ETAAS) to determine Cd, Cr, Pb, Cu and Ni. This method was also used to study migration of antimony from samples to food simulant under different conditions (temperature, pH). This thesis follows up on the thesis of Mrs. Kryštofová who studied recycled PET flakes.
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The study of PET bottles in terms of the content of risk elements
Kryštofová, Petra ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
This bachelor thesis deals with the issue of PET bottles in terms of the possible content of risk elements. The contents of antimony, copper and lead were determined in the PET packaging material and in the beverages contained in the bottles. A total of 15 samples of bottled still and infant water available in the Czech sales network were analyzed. The PET material was decomposed in an acidic medium under the action of microwave radiation under optimized conditions. Atomic absorption spectrometric methods with flame or graphite cuvette atomization were used to determine selected risk elements based on the predicted analyte concentrations. In the PET packaging material, 159.35 to 265.68 mgkg-1 of antimony were determined, the determined values of lead concentration were in the range of 10.96-20.23 mg·kg-1 and the copper concentration in the range of 0.11-7,52 mg·kg-1. In bottled water and in bottled infant water, antimony was identified only in samples labeled 6a, 8a, 9a and 15a, all lead concentrations were measured below LODPb, copper was determined only in samples 2a, 6a and 8a. In none of the samples did the concentrations given by the valid legislation be exceeded. The limits of these metals are not set in legislation in the packaging materials, only specific migration limits and they have not been exceeded. However, the high concentration of antimony in PET poses a potential risk of contamination of the contents of these packages.
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Temperature Profile in Reflow Soldering and Influence of Different PCBś and ComponentsThermal Capacities
Procházka, Martin ; Špinka, Jiří (referee) ; Starý, Jiří (advisor)
This thesis mainly deals with the prediction of temperature on the components and the PCB during reflow soldering. The theoretical part describes the particular solder reflow process, types of heat transfer and temperature profiles. The practical part is divided into forecasting temperatures if the conveyor is stopped and the temperature predictions when the conveyor is in motion. In both parts of the measured temperature is compared with the predicted temperatures, which show the success rate of prediction. The last part of this work is part of the simulation, which helps in proper understanding of the issues discussed.
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Utilization of bees products in cosmetics
Kobza, Martin ; Bednář, Michal (referee) ; Zemanová, Jana (advisor)
This bachelor thesis is focused on the problem of utilization of bees products in cosmetics. The aim of this thesis was to elaborate a literature review focused on individual bee products, their properties and their utilization in cosmetics. Honey, beeswax, propolis, pollen, royal jelly, apisin are said to be the bee products. Properties, utilization, determination of kvalitative properties and aplication into cosmetic products of individual bee products are mentioned in this thesis. Beeswax is used in production of lipsticks, creams and for basis of smears (oily creams). Royal jelly is aplicated into lotions, face masks, lipsticks, night creams, hair waters, hydration preparations etc. Honey is used for preparation of shower gels, soaps, body milks, hydration creams. Propolis is added into creams, body milks, body lotions, shampoos, lipsticks, soaps and mouth sprays. Pollen has significant content of vitamins, aminoacids and other substances in nature form for cosmetics. These substances are important for nutrition, regeneration and hydration of skin. Apisin is used in pharmacologic preparations, like healing creams and smears.
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The study of vertical mobility of heavy metals and their transfer to mushrooms
Jurnečka, Roman ; Doležalová Weissmannová, Helena (referee) ; Komendová, Renata (advisor)
This bachelor thesis deals with the issue of contamination of forest soils and edible mushrooms with lead, cadmium, copper and zinc in the Jeseníky Mountains, specifically in the Domašov and Vápenná forests. Sampling took place at 12 localities, divided into spruce and beech stands. Atomic absorption spectrometry AAS ContrAA 800D was chosen to determine the content of selected heavy metals. Based on the measured values of the concentrations of the studied metals and other soil properties, dependences were created to determine the vertical mobility of selected metals in the soil profile. Vertical mobility depends on the physico-chemical properties of the soil (pH, C and S content). The dependence of the content of selected heavy metals in the soil on the pH value of the soil was found. In the case of lead, the sorption capacity of the soil organic component was confirmed. The risk and above-limit content of Pb, Cd and Cu was found on the yellow-boletus mushroom. Cadmium shows the highest bioavailability. Lead was evaluated as the element with the lowest mobility.
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Thick-film sensors for heavy metals detection
Gajdoš, Libor ; Majzlíková, Petra (referee) ; Prášek, Jan (advisor)
This project describes the possibilities of heavy metals detections in solutions using differential pulse voltammetry with tree-electrode electrochemical thick-film sensors. In the theoretical part, the thick-film technology is described as well as thick-film pastes’ types and compositions, followed by introduction to electrochemistry and electro-analytical methods of measurement. This project also describes the three measured heavy metals – cadmium, lead and copper. In the practical part, heavy metals’ ions detection in solutions using carbon working electrode and determination of the detection limit and sensitivity are described and discussed. Finally the evaluation of obtained results and results comparison to hygienic limits are included.
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Corrosion layers removal in low-pressure plasma
Kujawa, Adam ; Grossmannová, Hana (referee) ; Krčma, František (advisor)
A plasmachemical reduction of corrosion layers on copper was studied. In this case two series of copper samples were prepared and putted in two corrosive environments for one week. The first corrosive environment contained a concentrated nitric acid and the second environment contained a concentrated sulfuric acid. Samples thus prepared were ready to be plasmachemicaly treated. The plasmachemical reductions took place in low-temperature, low-pressure, non-isothermal, high-frequency-inducted hydrogen plasma on the Faculty of Chemistry in University of Technology in Brno. The discharge was generated in continual or pulse mode with changeable pulse ratio. To monitor the reduction process an optical emission spectroscopy was used. The radiation from plasma discharge was measured by an optical spectrometer in the intervals of 1 to 10 minutes. An object of our concern in collected spectrum was the radiation of OH radicals with electromagnetical wavelenght in a range of 305 – 330 nm, and which were produced in a reaction between the hydrogen radicals and the oxygen atoms, contained in the corosion layers. A rotation temperature of plasma was calculated from the spectrums of OH radicals in a dependence of discharge conditions. Gathered findings will give us a better knowing of this conservation technique, that is used for treatment of the corroded surfaces of the archeological artifacts, and will also allow more provident appliance of this method on a copper historical objects.
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Reconstruction of the town spa in Malé Svatoňovice
Macek, Štěpán ; Špiller, Martin (referee) ; Guzdek, Adam (advisor) ; Kalousek, Lubor (advisor)
The aim of the bachelor thesis was to prepare a documentation for building permits and a part of the documentation for the building construction on the basis of an architectural study, developed in the „AG35 – Monuments Restoration Studio“ module. The topic of the studio work was to think about the appropriate use of a listed building in the historic center of the village of Malé Svatoňovice and to create an architectural study. I have proposed the following concept. The building should serve as a municipal house, so I have concentrated the corresponding functions here: the municipal office, the ceremonial hall, the museum, doctors labs, cosmetics, the pharmacy and finally the spa, which had a long tradition here. When restoring an object, I proceed synthetically. I examine the quality and preservation of individual layers. Then I highlight the best of each one. If some layer have not been preserved, but still have had its qualities, I remind it in a new language. I think it was Tadao Ando who said, "If the genius loci is to be legible, it must be revived and provoked by inventive inputs." I combine modern with historical using timelessness.
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