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Comparison of aroma profile of selected types of sweets
Polochová, Petra ; Zemanová, Jana (referee) ; Vítová, Eva (advisor)
This diploma thesis focuses on identification of aroma active substances and sensory analysis in samples of non-chocolate sweets. For experimental part jelly candies were chosen as model samples. Specifically gummy bears with strawberry, lemon, apple and orange flavour were used. The theoretical part deals with the legislation and technology of manufacturing non-chocolate sweets, characterization of aroma compounds including those which could be allergenic. Furthermore this thesis describes a method of their determination using solid phase microextraction and gas chromatography with mass spectrometry. The end of the theoretical part is dedicated to methods of sensory analysis that were used. In the experimental part, the chosen method HS-SPME-GC-MS was used to identify volatile aroma active substances in selected samples of jelly sweets. The substances that are potentially allergenic were also quantified. For the evaluation of sensory quality scales, profile test and overall acceptability were used. The single samples differ in number and type of volatile compounds depending on producer and flavour. Altogether 119 compounds were identified including 12 allergenic.
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Verifying of the method for assessment of allergenic aroma compounds in sweets
Maňáková, Adriena ; Diviš, Pavel (referee) ; Vítová, Eva (advisor)
This thesis deals with the assessment of aroma active compounds in non-chocolate confectionery and their influence on sensory quality. In the theoretical part the production technology of non-chocolate confectionery from raw materials to final product is described. Furthermore, aroma active substances, including those potentially allergenic, are characterized, and the method for their determination by solid phase microextraction and gas chromatography with mass spectrometry is briefly described. Sensory analysis and sensory evalutation methods are briefly desribed. Within expermental part of the work selected parametres of the HS-SPME-GC-MS method were optimized, aroma compounds in samples of hard candies were identified, and 24 potentially allergenic aroma substances were identified and quantified. Finally, a sensory analysis of these samples was performed. Differences in the number and type of volatile compounds were found between the samples. Overall 393 compounds were indetified including 19 allergens.
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Mitochondria as a target of anticancer therapy.
Dvořák, Aleš
RK se podílí a prolifera i ádorový h u ěk ve stíže ý h zkrá e é Kre sově klu v tváří reverz í reak í z OG itrát, který ůže ýt e portová do tosolu, kde slouží jako prekurzor ast ý h k seli a další h olekul. )ároveň IDH při RK spotře ovává stej ě tak i při s téze HG NADPH. RK se tak z výzku u zdá ještě zají avější, e oť ůže ovliv it produk i ROS a íru o idač ího stresu. HG ůže ýt s tetizová a IDH i ěkolik další h e z ů. HG regulač í olekul součas é do ě je v užívá Bývá oz ačová jako ož ý i hi itor α DD , jež se pod í a růz ý h epige eti ký h z ě á h a zv šují alig itu rakovi ého fe ot pu spoje ou se z ě ou prolifera e u ěč ý h li ií h kar i o u prsu a další h uňká h, včet ě pri ár í h potka í h fi ro lastů a aktivitě respira e. de o strují, že HG ádorový h uňká h, a aví že ve zdravý h uňká h z ě hladi ovlivňují prolifera i. elkově jeví jako vhod ý íl proti ádorové terapie, zej é a ve světle edáv ý h o jevů, ve který h se ukázalo, že utova á íře s tézu α Klíčová slova: MS, uňk prs ího 6, fi ro last , HG/ OG po ěr, C izotopi ké z ače í, prolifera e fi ro lastů, h po ie
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The content of aroma active compounds in sweets
Paulišová, Sabina ; Hrstka, Miroslav (referee) ; Vítová, Eva (advisor)
This bachelor thesis focuses on identification of aroma active compounds in selected samples of non-chocolate sweets. Based on the results obtained, the aromatic profile of the individual samples is compared. The theoretical part deals with aroma active compounds, legislation and technology of manufacturing non-chocolate sweets. Further experimental technique and the methods used in practical part, namely solid phase microextraction and gas chromatography with mass spectrometry detection are presented. In the experimental part volatile aroma active substances were identified in green colored jelly candy samples available in the common market. For this purpose, the HS-SPME-GC-MS method was used. The individual samples differed in type and number of volatile compounds, depending on the manufacturer. In total 72 different compounds, including 11 aldehydes, 14 alcohols, 27 esters, 1 heterocycle, 8 carboxylic acids, 6 ketones, 4 hydrocarbons and 1 sulfur compound were found.
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Comparison of aroma profile of fruit distillates
Koubek, Miroslav ; Veselá, Mária (referee) ; Vítová, Eva (advisor)
This master thesis deals with the assessment of aroma active compounds in fruit spirits. In the theoretical part the production technology of fruit spirits from raw materials to final product is described. Furthermore, aroma active substances are characterized, and the method for their determination by solid phase microextraction and gas chromatography with mass spectrometry is described. The aim of the experimental part was the identification of volatile substances in different kinds of fruit spirits. Aromatic compounds were identified by the SPME-GC-MS. Domestic fruit spirits obtained from private growers were used as model samples. The differences in the number and type of volatile compounds were found between the samples. Overall 53 volatile compounds were identified. These were composed of 25 esters, 9 alcohols, 5 aldehydes, 4 alkenes, 2 ketones, 1 carboxylic acid and 7 other compounds.
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Study of chemical reactions products in the prebiotic atmospheres
Manduchová, Ivana ; Slavíček,, Pavel (referee) ; Mazánková, Věra (advisor)
The diploma thesis is focused on the study of chemical reaction products in prebiotic atmospheres. The theoretical part deals with the main theories of composing the atmosphere of the early Earth, hypotheses of the origin of life and genetic code in the form of RNA, the atmosphere of the moon Titan and the basic characteristics of the gliding arc discharge, and the analytical techniques used in the diploma thesis. In the experimental part, study of products was carried out by experimental atmospheric simulations in a special stainless steel reactor in various mixtures of gases N2, CH4, CO2 and O2. The electrical discharge for atmospheric simulation was generated by an electrode configuration for the gliding arc discharge and glow discharge. Detection and identification of chemical reaction products was performed by Gas Chromatography with Mass Spectrometry (GC-MS) and Flame Ionization Detector (GC-FID), Testo 350 M/XL and Proton Transfer Reaction Mass Spectrometry (PTR-MS). A theoretical kinetic model was created to predict and confirm the detected products. During the experiments, the dependence of the product intensity on changes in the composition of the gaseous mixture and the applied value of the electric current was also observed.
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Influence of aroma compounds on sensory quality of sweets
Motúzová, Eliška ; Zemanová, Jana (referee) ; Vítová, Eva (advisor)
This master´s thesis is focused on determination of aroma active compounds in non-chocolate sweets and their influence on sensory quality/flavour. The theoretical part describes production of non-chocolate sweets, characterizes aroma active compounds including allergenic ones, method for their determination by solid-phase microextraction and gas chromatography with mass detection. For experimental part were used as model samples gummy candies purchrased in regular market. Four flavors were used, specifically yellow (lemon), green (apple), red (strawberry) and orange (orange). The HS-SPME-GC-MS method was used to identify volatile aroma active compounds. To evalutate the sensory quality were used scales, a profile test, and a time course evaluation. Owerall 120 volatille compounds were identified including 8 allergens.
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Aroma active compounds of selected types of herbs
Škutová, Pavla ; Hrstka, Miroslav (referee) ; Vítová, Eva (advisor)
This diploma thesis deals with the identification of aroma active compounds in medicinal herbs. The group consists of 5 types of herbs: lemon balm (Melissa officinalis), pot marigold (Calendula officinalis), clary sage (Salvia sclarea), milk thistle (Silybum marianum), goat’s rue (Galega officinalis). These plants are known for their positive effects in folk medicine. The SPME-GC-MS method was chosen to characterize the fragrances. During the identification of volatile compounds, emphasis was put on suspected fragrance allergens listed in EC Regulation 1223/2009 in Annex III. Overall 106 compounds were identified together with 8 allergens in lemon balm, pot marigold contained 104 compounds with 7 allergens included, 82 compounds including 5 allergens in clary sage, 73 compounds were identified in milk thistle including 6 allergens and 110 compounds with 9 allergens included in goat’s rue.
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Mitochondria as a target of anticancer therapy.
Dvořák, Aleš ; Ježek, Petr (advisor) ; Poučková, Pavla (referee) ; Vecka, Marek (referee)
Mitochondrial isocitrate dehydrogenase 2 (IDH2) catalyzes reductive carboxylation (RC, reverse Krebs cycle pathway) and 2HG synthesis (2HG) - metabolite of which many scientists are interested. 2HG may be concurrently synthetized in cytosol by IDH1. RC is involved in anabolic reactions necessary for cell proliferation - produces citrate, fatty acid precursor - especially in hypoxia. IDH2 and IDH1 are not the only enzymes that are involved in 2HG synthesis. Recently, several enzymes, which participate in 2HG production, have been discovered. 2HG is useful in cancer diagnostics due to its overproduction by transformed cells. Moreover, 2HG may cause epigenetic changes via inhibition of 2-oxoglutarate dependent dioxygenase. In this work, the importance of RC and 2HG synthesis in cancer and healthy cells was investigated by gas chromatography with mass spectrometry detection as well as IDH2 influence. We found that IDH2 significantly participates in reverse RC and 2HG synthesis in breast cancer cell lines and uses glutaminolysis as a supplementary anaplerotic pathway. RC is increased by hypoxia, inhibition of respiration, and decreased by activation of respiration or hypocapnia. We confirmed 2HG synthesis and RC in healthy cells (fibroblasts, breast epithelial cells etc.) as well as in cancer cells....
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Natural sources and sinks of volatile chlorinated hydrocarbons in the spruce forest ecosystem
Štangelová, Pavla ; Tesařová, Eva (advisor) ; Pavlík, Milan (referee)
Biogeochemical cycle of chlorine, particularly the formation of organically bound chlorine is still not well understood. In continental ecosystems chlorides act as source of chlorine, and also as a stress factor. Chlorides originate from precipitation of marine cloud masses. Organically bound chlorine in the environment is formed naturally by biotical and abiotical way. The biotical factors are microorganisms, plants, soil enzymes and animals. Volatile chlorinated hydrocarbons (VOCl) represent one group of organically bound chlorines. Several volatile chlorinated hydrocarbons reacts with atmospheric ozone, consequently causing depletion of the ozone layer. The most important known terrestrial source of volatile chlorinated hydrocarbons is the spruce forest ecosystem. Chlorine in the soil can be transformed by microorganisms into organically bound chlorine or translocated by transpiration stream in plants, where they are also transformed enzymatically into organically bound chlorine, and both of them can be emitted into the atmosphere. Too large amounts of chloride can affect the physiological functions of plants. In this thesis experiments were designed for measuring the natural emissions of volatile halogenated hydrocarbons from plants and fungi, with various periods of incubation, and also to...
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