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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Využití mikroenkapsulace při vývoji hydrogelových nosičových systémů / Application of microencapsulation techniques in development of novel controlled-release systems.

Karásková, Iva January 2017 (has links)
This diploma thesis deals with application of microencapsulation techniques in development of hydrogel controlled-release systems in which the main role is played by humic acids, biopolymer chitosan, compound fertilizer NPK and 3-indoleacetic acid. This paper continues my bachelor thesis topic about utilization of polyelectrolyte complexes. The aim of this work was to develop a literature review focusing on the microencapsulation techniques and according to its results optimize the method. Microencapsulation was performed with a commercial encapsulator BUSCHI B-395 Pro and a release of individual components into a water was measured. An amout of released substances was measured by UV-VIS method and HPLC analysis. Practical part also included testing of repeated swelling and drying. It was found that suitable composition and combination of ingredients form hydrogels for further use in agriculture.
72

Monitoring obsahu mastných kyselin v průběhu výroby sýrů / Monitoring of fatty acids content during cheese production

Rajnochová, Veronika January 2017 (has links)
This master thesis deals with the monitoring of fatty acids during production of natural Edam cheeses, i.e. natural hard cheeses with low heat curd, and of processed cheeses, which were produced from them. The theoretical part briefly characterizes the natural Edam cheese and processed cheese, the main attention is paid to lipids, fatty acids and the possibility of their determination. In the experimental part the content of fatty acids in the model samples of natural and processed cheese produced at Tomas Bata University in Zlín was determined. The method according to ISO 1735 was chosen for extraction of lipids from the samples, the method according to ISO 5509 using methanol solution of potassium hydroxide was chosen for the esterification of fatty acids. The resulting methyl esters were determined by gas chromatography with FID detection.
73

Stanovení neesterifikovaných mastných kyselin v krevní plasmě / Determination of non-esterified fatty acids in plasma

Lacinová, Petra January 2014 (has links)
The determination of non-esterified fatty acids (NEFA) in plasma is possible by many routine biochemical methods. For more detailed metabolic studies it is required to analyse the fatty acid (FA) profile. The NEFA profile determination is usually performed by the capillary gas chromatography (GC), but the sample preparation is not uniform. NEFA may be isolated by the extraction process or by the preparative thin-layer chromatography (TLC). The aim of this study was to compare these two separation procedures. The samples of pooled plasma from volunteer donors were analyzed by capillary GC after previous separation procedure by the TLC and the liquid-liquid extraction. The results were compared by the t-test for both the absolute concentration of individual FA provided by the internal standard (margaric acid) method and the relative abundance (Rel%). The reproducibility of the results was significantly better for the liquid-liquid extraction method than the TLC. The relative standard deviations (RSD) of the FA groups (unsaturated, monosaturated and polysaturated) were from 4.3 to 11.3 % vs. 8.6 to 33.8 % for the relative abundance and from 16.5 to 25.5% vs. 15.4 to 47.4% for the absolute concentration. For each FA, which were represented by more than 0.1 Rel %, RSD ranged from 4.5 to 47.8% vs. 9.5 to...
74

Hydroxyskořicové kyseliny v moštových odrůdách révy vinné

Brzobohatá, Anna January 2017 (has links)
In the thesis the author observes a progression of volume of hydroxycinnamic acids in grapes of a grapevine. Ten brands of grapevine originating from Mikulov vine subregion village Lednice were selected for the experiment that proceeded in September and October 2016. The development of hydroxycinnamic acids during a process of maturing was observed with four out of these brands as well as relation of their volume to basic analytic variables of a must. The remaining six vine brands were compared for volume of hydroxycinnamic acids as an attribute of a given brand in two takings. Literary part of the thesis approaches matters of fenolic substances with focus on hydroxycinnamic acids, their structure and forms. This part also contains a brief characteristics of the ten types of grapevine selected for the experiment.
75

Úloha huminových látek ve zmírňování negativních dopadů působení solí na rostliny ječmene jarního

Jarošová, Markéta January 2015 (has links)
Salinity induced by various sodium salts (NaCl and Na2SO4) led to changes in growth parameters that differs depending on used cultivar and pH of applied salt solution. Cultivar Radegast showed the highest sensitivity to salinity that was reflected in a reduction of shoot and root growth, a decrease of tissue water content, an excessive sodium accumulation in shoots and a radical formation of ROS in the root tips. Subsequent experiment using various types of humic acids revealed that technical humic acid (HA; 6.0 mg . l-1), unlike Lignohumát Max, stimulates NaCl-treated plant growth and simultaneously reduces accumulation of sodium in their tissues.HA applied into culture solution is able to induce an enhancement of certain metabolites(syringic acid and lactic acid in shoots, quinic acid and malic acid in roots, andascorbic acid, reduced glutathione, phytochelatin 2 and free amino acids in shoots). However, NaCl caused a decrease of majority free amino acids (except for proline and histidine), phenolic acids and antioxidants in leaves. On the other hand, an increase of lactic acid and quinic acid was observed in roots. Salinity significantly induced oxidative stress; it is evident from the increased activity of antioxidant enzymes (APX, CAT, GR and SOD). HA was able to mitigate NaCl-induced oxidative stress, as also evidenced by fluorescence microscopy. Simultaneously, HA was also able to reduce NaCl-induced excessive accumulation of sodium content in cultivar Radegast.
76

Ověření použití sekundárních produktů po lisování oleje v kosmetickém průmyslu

Huláková, Lenka January 2019 (has links)
The thesis describes the pressing of oils from fruit species, presents their selected quality parameters and evaluates the possibilities of their application in the production of cosmetics. The oil was pressed from almond, hazelnut, royal, apricot, peach, currant and rosehip seeds. Particular oils were obtained by cold pressing to produce the secondary products used. Selected substances such as fatty acid content. It also included the identification of qualitative parameters such as peroxide number, acidity number, oil acidity, oil saponification and iodine content in oils. Results show high MUFA content. Oil with its highest content is walnut (85.97%). The predominant acid in oils is oleic acid. Plum oil has the best antioxidant stability. The highest acid number is apricot oil (3.55 mg KOH.g-1). Peach oil (351,60 mg KOH / g oil) has the highest saponification number. The highest iodine number has almond oil (54,50 g.l2.100 g-1). Oils and secondary products have been used in the manufacture of cosmetic products. The choice of cosmetic products was based on market research. They were inspired by current cosmetic trends.Formula clause:The reason for postponing the publication of final thesis entitled Verification of using the secondary products after oil pressing in the cosmetic industry is the use of results of work for application output, cooperation with the commercial sector and further possible commercialization. Estimated delay is three years.
77

Hodnocení změn kyselin v hroznech a vínech

Sládečková, Vanesa January 2019 (has links)
The diploma thesis “Evaluation of acid changes in grapes and wines” is divided into theoretical and practical part. In the theoretical part were described individual acids, possibilities of their regulation in musts and wines and selected methods of their determination. In the practical part of diploma thesis, the parameters of the grapes (pH, total titratable acids, tartaric acid and malic acid) were observed during the ripening period. The varieties Müller Thurgau, Pálava, Frankovka and Svätovavrinecké were studied. Berries were taken at regular weekly intervals from 2.8. to 20.9. 2018. In the second part of the experimental part of the work, the wines were monitored in three stages of vinification. The pH, total titratable acid, tartaric, malic and lactic acid parameters were monitored. The results were interpreted using tables and graphs. Subsequently, they were statistically evaluated and described.
78

Studium složení palmového oleje z hlediska autenticity

Heinz, Petr January 2018 (has links)
The palm oil is the most desirable raw material in a wide range of industry in the 21st century. It is a basic material for food, cosmetics, biodiesel and many other products. However, it’s production has a negative impact on the environment. In this thesis the palm oil authenticity is judged according to the differences in composition depending on the conditions of cultivation, which is related to the certification of this raw material. The fatty acid spectrum in the samples of palm oil was determined by method of gas chromatography coupled with flame ionization detection. In terms of total fatty acids content, the non-certified palm oil (fat sample 1) containing 0.969 g.g-1 fat (after three months storage 0.880 g.g-1 fat) is better than certified palm oil (fat sample 2) containing 0.648 g.g-1 fat (after three months storage 0.533 g.g-1 fat).
79

Nový polymorfizmus genu apolipoprotein A2 a jeho asociace s obsahem mastných kyselin u prasat

Sukhov, Oleg January 2018 (has links)
This thesis studies the problematic of the new polymorphism APOA2 gene and that association with fatty acids contain in a group of Czech Large White pigs. APOA2 gene (ID: 100153243) is a candidate gene for porcine meat quality. The aim of thesis was to analyze the influence of selected polymorphisms on fatty acids and intramuscular fat contain. Among fatty acids was observed a contain of: tetradecenoic acid, palmitic acid, palmitoleic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, arachidonic acid, arachidic acid a eicosapentaenoic acid (EPA). Have been used molecular-genetic methods such as primers design in the OLIGO software, PCR, gel electrophoresis a sequencing by Sanger method. The results were processed by form of genotype frequency and followed by associative analysis with a mixed linear model. The values of the relative alleles frequency of polymorphism APOA2 T>A rs80803879 were as follows: A = 0,086, T = 0,914 and relative alleles frequency of APOA2 G>A rs331415849: A = 0,068 a G = 0,948. Polymorphism associations were found for fatty acids: myristoleic acid, acid palmitoleic acid, oleic acid, arachidonic acid, and arachidic acid.
80

Vliv přídavku vybraných olejů na depozici mastných kyselin ve tkáních pokusných živočichů

Vymazalová, Pavla January 2018 (has links)
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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