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Application of Mass Spectrometry for the Determination of Oxidative Stress Markers and Mycotoxins
Čumová, Martina ; Večeřa, Zbyněk (referee) ; Hajšlová, Jana (referee) ; Vávrová, Milada (referee) ; Čáslavský, Josef (advisor)
The first topic presented in the dissertation thesis is determination of isoprostanes as markers of oxidative stress and other compounds affected by presence of oxidative stress. Isoprostanes iPF2-III, iPF2-VI, iPF2-VI, astaxanthin and polyunsaturated fatty acids (PUFA), especially arachidonic acid (AA) were monitored in Atlantic salmon eggs (Salmo salar). Methods for the determination of these compounds have been developed and optimized using chromatographic separation coupled to conventional or mass spectrometric detection. Freshly laid eggs, eyed embryos and non-viable eggs were used to test a general hypothesis that egg viability can be affected by susceptibility to oxidative stress, either through the specific fatty acid concentration and/or the antioxidant capacity of the eggs. Levels of isoprostanes and arachidonic acid (AA) were significantly higher in non-viable eggs than in control (eyed embryos) as well as relative abundance of PUFA. While no difference of isoprostanes was found between freshly laid and control those from the Atlantic stock except iPF2-VI which was observed under the LOQ in the control. Higher levels of PUFA and AA in comparison with the control were observed in the freshly laid eggs. However, the only statistically significant difference was observed in the amount of astaxanthin. Different levels of PUFA and astaxanthin may be related to their biochemical consumption during the development of eggs. This work evaluated potential effect on the viability of eggs Salmo salar due to the presence of oxidative stress. The monitoring of mycotoxins in food and feed was the subject of the second topic. Mycotoxins are secondary metabolites produced by fungi. They are ubiquitous undesirable natural contaminants that are toxic for humans and animals. Today are known more than 500 mycotoxins. However, only few of them are regulated by the European Union. The European Food Safety Authority (EFSA) was asked by the European Commission to provide a scientific opinion on other mycotoxins for which statutory limits could be developed. In this study is proposed simultaneous screening allowing fast, reliable and sensitive approach, identification and quantification of 17 mycotoxins in food and feed sample. The method includes both mycotoxins regulated by the EU and selected mycotoxins required by the EFSA (aflatoxins, deoxynivalenol, nivalenol, zearalenone, fumonisin, ochratoxin A, T-2 toxin, HT-2 toxin, enniatins and beauvericin). Analytes are isolated by the modified QuEChERS method. For separation and target mycotoxins detection, ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC –MS/MS) was employed. The method also allows determination of ergot alkaloids (ergocornine, ergosine, ergocryptine, ergocristine and their respective epimers). The developed method was used either for monitoring mycotoxins and ergot alkaloids in feed and raw materials and barley and malt prepared from it.
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VÝVOJ NOVÝCH RYBÍCH PRODUKTŮ PRO PŘEDŠKOLNÍ DĚTI
KALICOVOVÁ, Veronika
The aim of the diploma thesis was to develop newly innovative fish products. The intention is to increase fish consumption through new developed innovative fish products and proposed recipes. Fish supply healthy polyunsaturated fatty acids (PUFAs) and highly unsaturated fatty acids (HUFAs) to the human body, including eicosapentaenoic (EPA) and docosahexaenoic acid (DHA), which are essential for the proper development of the human organism. 11 new products and 13 new recipes were developed, which were subsequently sensory evaluated by the main target group of consumers. Preschool children were chosen as the target group of consumers, because their consuming habits are established in this life period. The new fish products have met all legislative standards and limits of food safety. Nine products were positively evaluated by the target group. Five products were selected for further analyses (fish balls, fish burgers, fish ham, fish mistura, fish sausages). The issue was theoretically studied according to worldwide research studies. In practice, the project was implemented with coordinated comprehensive cooperation with nutritionists, fish product technologists, but also with preschool facility employees, children and their families. The output of this work are new fish products which are available on the market. Fish products were made from the muscle of African catfish (Clarias gariepinus). The market offer of nutritionally high-quality foods which have a positive impact on human health has been increased. At the same, time several recipes from the African catfish (Clarias gariepinus), the common carp (Cyprinus carpio) and the rainbow trout (Oncorhynchus mykiss) have been proposed as a guide for easy preparation of healthy dishes.
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Určení a kvantifikace mastných kyselin ve vybraných rybích produktech
ONDROUCH, Petr
Determination and quantification of fatty acids in chosen fish products This study is dealing with fatty acids, their nutritional value for human health and the prevention of cardiovascular and other civilization diseases. We introduced catfish Clarias gariepinus biology and importance for the aquaculture and also as a candidate for a valuable source of n-3 PUFAS. The chemical-analytical approach was used to determine content of fatty acids in chosen meat products from mentioned extraordinary fish. Extraction of lipids, derivatization of fatty acids and gas chromatography (GC FID) were performed. Furthermore, the meat products from the Clarias gariepinus were compared with classical pork products - sausages. The results showed that fish products seem to be a valuable source of docosahexaenoic and eicosapentaenoic acid, the "classical" sausages, on the contrary, contain none of the desired fatty acids. Additionally, the fish products are designed as sausages and therefore resemble the "classical" ones which could be attractive even for the conservative consumers. Consumption of fish products will lead to elevation of daily intake of n-3 PUFAs and thus positively influence the common health by preventing cardiovascular and other civilisation diseases.
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Analýza mastných kyselin ve vybraných tkáních prasat po aplikaci rybího tuku do krmné dávky
Hrazdilová, Zlata
Literar review of thesis is focused on clasification of lipids, fatty acids characteristics, particularly polyunsaturated acids n3 alpha linolenic, eicosapentaenoic and docosahexaenoic acid; and polyunsaturated acids n6. There is description of metabolic reactions. Degradation by beta oxidation, biosynthesis and conversion to eicosanoids. Function and effect of eicosanoids to organism and health, nutritional representation of this fatty acids, fortification of food sources, feed in interest of improvement health condition and functional foods producing. The practical part is focused on fatty acids analysis in muscular, liver and adipose tissue of pigs after feed fortification by 2,5 % fish oil and 2,5 % palm oil in the diet. Lyofilizated samples were derivatized and determinated by gas chromatography method. Results were evaluated by statistics program.
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Vplyv prídavku vybraných olejov na zastúpenie mastných kyselín v živočíšnych tkanivách a homeostázu cholesterolu u modelového organizmu
Hnatová, Martina
The theoretical part of my thesis is based on the general classification and characterization of dietary lipids, especially fatty acids, cholesterol and lipoprotein particles. Also, their transport and absorption mechanisms are described, as well as medical complications that are closely linked to excessive lipid consumption. One part is used for the description of lipid extractions and determination of fatty acids. The experimental part is focused on the analysis of fatty acids in samples of liver, adipose and muscle tissues of laboratory rats after the addition of palm oil, safflower oil, fish oil and Schizochytrium microalgae oil into their diets. Lyophilized tissue samples were extracted and derivatized, followed by gas chromatography fatty acid determination. The results were then statistically evaluated.
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Depozice dietárních mastných kyselin ve vybraných vnitřních orgánech a tkáních pokusných živočichů
Štumarová, Klára
This diploma thesis deals with the issue of fatty acids containing distribution, metabolism, physiological properties and effects on health. In the experimental part there is detail descripiton of the experiment, where the amount of dietary fatty acids in the liver and visceral fat in rats was determined. Rats were divided into five groups, each of that was fed with mixture with 8% oil addition (palm oil, fish oil, safflower oil and Schizochytrium extract). The last group was fed with the mixture without any oil addition. The results of the experiment point to a high SFA content in feed with 8% fish oil addition. Although fish oil contains a significant amount of n-3 PUFA, high deposition of SFA could have negative effects on plasma lipid and lipoprotein levels. The most suitable oil is Schizochytrium microalga extract, which has a positive effect on EPA and DHA deposition, but does not contain significant amount of SFA, MUFA and PUFA n 6. Regarding the ratio of PUFA n-6/n-3, fish oil appears to be the second most suitable. The least suitable PUFA n-6/n-3 ratio is observed in safflower and palm oil.
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Srovnání depozice polynenasycených mastných kyselin ve vybraných tkáních dvou živočišných druhů
Papanová, Veronika
The diploma thesis is devided into two parts – theoretical and practical. The theoretical part deals with fatty acids, their nomenclature and chemical composition. Further the diploma thesis focuses on polyunsaturated fatty acids (PUFAs) – their analytical determination, metabolism, important representatives and influence on human nutrition. The practical part deals with the experiment, in which the fatty acids content was determined in mg/100 g using gas chromatography. Testing was carried out using model animals – rats Wistar Albino and pigs Landrace and Large White. By using statistical processing, the differences in the deposition of PUFAs in the livers of these animals, were compared.
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Vliv přídavku oleje do krmiva modelového organismu na zastoupení mastných kyselin ve vybraných tkáních
Kaňoková, Linda
The Master's thesis deals with the effect of feed enrichment with various types of oils on the deposition of fatty acids in selected tissues. Forty male Wistar Albino rats were divided into four groups and fed for 10 weeks daily ad libitum with a basic feed mixture enriched with 8 % palm, 8 % safflower, 8 % fish oil or 8 % microalgae Schizochytrium sp. oil. Rats had also free access to the drinking water. Fat from the tissue samples (liver, muscle, visceral fat) was extracted, converted to methyl esters and analyzed with usage of gas chromatography. The results of the experiment show that the addition of various types of oils to the feed of model organism can influence the deposition of fatty acids in its tissues. The addition of fish oil and microalgae Schizochytrium sp. oil caused statistically significant decrease (p < 0,05) in the ratio of PUFA n-6/n-3 in all observed tissues to a value of 1 or less compared to the addition of palm and safflower oil. Low ratio of n-6/n-3 polyunsaturated fatty acids is considered to be more desirable in reducing the risk of cardiovascular diseases.
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Vliv přídavku vybraných olejů na depozici mastných kyselin ve tkáních pokusných živočichů
Vymazalová, Pavla
The thesis contains a theoretical overview, which has focused on classification of lipids, fatty acids and their metabolisms, with emphasis on polyunsaturated fatty acids inclusive of their conversion to eicosanoids, functions and effects of eicosanoids on human health. Furthermore, the theoretical part of the thesis has focused on a food’s enrichment of polysaturated fatty acids n-3 and several possibilities of analytical determination of fatty acids. The practical part of the thesis has aimed attention at the determination of fatty acids in the liver, fat and muscles’ tissue of the experimental rats. The animals were fed with a standard feed mixture, which contains 5 % of fish oil, 5 % of palm oil, 5 % of safflower oil and 5 % of Schizochytrium algae extract. The obtained fat was extracted from the lyophilized samples followed by derivatization and analytical determination of the fatty acid derivatives by gas chromatography. From the results of the experimental part could be determined, that the addition of 5 % of fish oil to the feed mixture of the experimental animals increased the deposition of EPA and DHA in all examined tissues (p < 0.05). The addition of 5 % of the Schizochytrium extract to the animal’s feed mixture had an impact on the effective deposition of DHA and DTA in the examined tissues of all used oils (p < 0.05). Both of the previously mentioned oils can be considered as the most effective nutraceuticals for reducing the ratio of PUFA n-6/n-3 in the food. Unlike the addition of 5 % of safflower or 5 % of palm oil (as a control), ratios of PUFA n-6/n-3 were many times higher. Therefore, from the healthy point of view, this can be concluded as inappropriate.
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