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Srovnání čiřicí schopnosti vybraných čiřidelMarko, Valéria January 2016 (has links)
Diploma thesis was drawn up at Mendel University in Brno, Faculty of Horticulture in Lednice, the Institute of Post-Harvest Technology of Horticultural Products in 2014 - 2016. The purpose of this work was to observe and analyse the influence of selected fining agents on protein stability changes, the concentration of the certain important substances in wine such as polyphenols and anthocyanins before and after their application. Furthermore, organoleptically evaluated clarity and colour changes before and after their wine clarification. During fining process some important substances for the wine are eliminated. Within the analysis of complex polyphenols and anthocyanins after fining process of white, red and rosé wines, the statisticaly significant losses of these substances were recorded in the range of 13 - 33 % of their original value. After comparison the ability of fining agents for white wine can be recommended bentonite Majorbenton B and mixed product Vinosil Plus, for red wines albumin Albuvin and for rosé wines albumin Albuvin.
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Vybrané alkoholové extrakty bezu černého pro využití v kosmetologii / Selected alcohol extracts of Sambucus nigra for use in cosmetologyBalonková, Daniela January 2019 (has links)
This thesis focuses on the preparation of selected alcohol extracts of elderberry and their use in cosmetology. In the theoretical part are described the botanical properties of the elderberry (Sambucus nigra). There are introduced and characterized bioactive compounds and toxic compounds contained in all vegetative parts of the plant. Attention is mostly focused on compounds with antioxidant properties. The theoretical part also contains a description of basic analytical methods, which are used in the practical part to characterize compounds contained in elder flowers. The practical part focuses on the optimization of the preparation of alcohol extracts with the aim to prepare the extract with the greatest possible content of polyphenols with respect to economy and production costs. Factors such as selection of the appropriate solvent, solvent to plant material ratio, solvent temperature, and extraction time are examined. Based on the total polyphenol concentration measured spectrophotometrically by the Folin-Ciocalteu method, the most suitable solvent is 60% ethanol, the ratio of plant material to solvent is 1:8, the laboratory temperature of solvent and the extraction time of 24 hours.Under these conditions, an ethanol extract is prepared, analyzed and determined selected properties, such as refractive index and density. Rutin, chlorogenic, caffeic and ferulic acids are identified by HPLC with a DAD detector. The pH value of alcohol extract is 5.743 ± 0.006, the refractive index is 1.365 ± 0.02 at 22.7 ° C and the density is 0.9288 gcm-3. By liquid chromatography the concentration of chlorogenic acids is quantified as 0.104 gl-1, caffeic acid as 0.086 gl-1 and ferulic acid as 0.060 gl-1. The extract is incorporated into cosmetic products, that are used in balneology. Prepared products are toilet soap and bath salt.
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Izolace antibakteriálních sloučenin z kávové sedliny / Isolation of antimicrobial compounds from spent coffee groundsKurzová, Pavlína January 2020 (has links)
Coffee grounds are one of the very valuable lignocellulosic wastes that have been able to be processed and used for isolated phenolic substances. Many phenolic substances isolated from lignocellulosic wastes have antimicrobial properties. Aim of this thesis is isolation phenolic substances from spent coffee grounds extract and their available antimicrobial properties. Two isolation ways were applied to receive phenolic substances from spent coffee grounds: 1) solvent extraction (hexane, 75% ethanol, 70% acetone, diethyl ether, and ethyl acetate) and 2) release of active substances by alcoholic fermentation. All isolated materials were characterized by the viewpoint of concentration of reducing sugars, polyphenols and flavonoids. Subsequently, their antimicrobial activity was determined by using agar diffusion and broth dilution methods. Two gram-positive bacteria (Bacillus subtilis and Micrococcus luteus), one gram-negative bacteria (Serratia marcescens) and two yeasts (Candida glabrata and Saccharomyces cerevisiae) were used for antimicrobial testing. High-performance liquid chromatography (HPLC) was used to identify phenolic substances in the extracts. First, the results showed that the isolated sample with the highest antimicrobial activity was 70% acetone extract. This extract contained chlorogenic acid, gallic acid, caffeic acid and coumaric acid according to HPLC. The ethyl acetate extract showed the lowest antimicrobial activity. Second, after lyophilization, the isolated materials also revealed high antimicrobial activity. The highest antimicrobial activity displayed the materials obtained by the extraction with 70% ethanol. This sample contained chlorogenic acid, gallic acid and caffeic acids. Next, samples with phenolic compounds were obtained by the alcoholic fermentation of spent coffee grounds. These samples showed similarly to the previous solution extracts significant antimicrobial activity. Interestingly, the unfiltered samples received directly after alcoholic fermentation also showed antifungal properties. The characterization of phenolic compounds by HPLC showed similarly as in previous examples that chlorogenic, caffeic and gallic acids were present in these samples.
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Stanovení aktivních látek v medu / Analysis of active substances in honeyJelénková, Zuzana January 2008 (has links)
This diploma thesis was focused on biologically active compounds determination. 26 samples of honey, one sample of propolis and one sample of royal jelly were analyzed. Honey were harvested in year 2006 and 2007 and bought in retail chain, special shops and directly from bee-keeper. Samples were analyzed by titration, spectrofotometry, LC/MS and RP-HPLC methods. The study was focused on analysis of antioxidants. Followed groups of antioxidants were determined: flavonoids, catechins, carotenoids, vitamins E, C, A. Authenticity of quality was determined by hydroxymethylfurfural analysis. Average values of total antioxidant capacity ranged (12.75-137.49) mmol .100 g-1. Average values of total phenolic ranged (8.51-61.34) mg .100 g-1 and average values of total flavonoids ranged (0.75-6.04) mg .100 g-1. Honey samples contained (41.83-585.10) g .100 g-1 of rutin, (9.30-313.40) g .100 g-1 of myricetin, (6.5-171.90) g .100 g-1 of luteolin, (3.19-436.37) g .100 g-1 of quercetin, (2.10-242.66) g .100 g-1 of apigenin, (0.15-105.12) g .100 g-1 of caempferol and (0.07-17.52) mg .100 g-1 of naringenin. From group of catechins there were measured (5.98-310) g .100 g-1 of catechin, (17.77-486.29) g .100 g-1 of epicatechin, (0.18-64.90) g .100 g-1 of catechin gallate and (0.59-140.56) g .100 g-1 of epicatechin gallate. From lipophilic compounds the most abundant in honey samples was tocopherol, its value ranged (29.20-8531.17) g .100 g-1. Content of ascorbic acid ranged (0.65-4.65) mg .100 g-1. Content of hydroxymethyl.furfural. ranged (0.26-4.06) mg .100 g-1. By LC/MS method luteolin, naringenin, protocatechin acid, coffee acid and p-cumaric acid in honeydew were detected and, furthermore, kyanidin and pinocembrin in floral honey were found. Mono-floral honey contained biologically active compounds the most, imperceptibly less contained multi-floral honey and honeydew honey. Acacia honey contained the lowest amount of biologically active compounds.
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Využití metody LC/MS k analýze vybraných přírodních fyziologicky aktivních látek / Use of LC/MS technique to analysis of some physiologically active natural compoundsTrčková, Marie January 2008 (has links)
Presented work is focused on application of combined instrumental method RP-HPLC/ESI-MS in analysis of several groups of natural compounds with positive physiological activities. Especially some antioxidants were studied in commonly and abundantly consumed food. Moreover some other substances than standard compounds were observed in complex dies. In conclusion the HPLC/ESI-MS method is comparatively advantageous in phenolic analysis, while another type of ionisation would be used in case of carotenoid compound.
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Stanovení aktivních látek v instantních nápojích určených pro dětskou výživu / Analysis of active substances in instant beverages for child´s nutritionJašková, Martina January 2011 (has links)
The aim of presented diploma thesis was to characterize baby beverages for early infant feeding. Theoretical part deals with baby foods and beverages including breast milk. Practical part is focused on analysis of active substances in 21 commercially available fruit and herbal instant granular baby beverages and in 3 packaged tea bags for infant and toddler age. To evaluation of antioxidant properties some group parameters were used - total polyphenols, total flavonoids, total antioxidant activity and anthocyanins. All of them were analysed by using spectrophotometrical methods. For identification and quantification of individual phenolic substances was used RP-HPLC/UV-VIS and HPLC/PDA/LC-MS, identification of individual mono- and disaccharides was performed by HPLC/RI. L-ascorbic acid supplemented to some children's drinks was analysed by HPLC-NH2/UV. Protein analysis was performed by Experion microfluidic electrophoresis system (BioRad) and protein concentration was verified by colorimetric method. In general, the highest content of phenolic compounds was shown in tea bags when compared with instant granular beverages that contain mostly added simple carbohydrates. Using contact microbial tests proved immediately after opening and also during manipulation with tea boxes was verified that analysed baby teas are in agreement with strict hygiene requirements for baby beverages.
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Stanovení některých nutričních faktorů ve vybraných druzích ovoce / Determination of some nutrition factors in selected kinds of fruitSmělá, Margita January 2011 (has links)
Diploma thesis is concerned with determination of some nutrion factors and vitamin C in various cultivars of apples (Pirus Malus, L.) and quinces (Cydonia oblonga, Mill.). In theoretical part there are described general characterization in selected kinds of fruits, their medically significant sunstances and utilization of these fruits. Main focus is paid to vitamin C. There are described its chemical properties and effect for human health. Various methods for determination of some nutrion factors with focus on determination of vitamin C by high-performance liquid chromatography. In experimental part, total of 27 various cultivars of aplles and 16 various cultivars of quinces were analyzed. These cultivars are from grower station Faculty of garden of Mendel university. For determitation vitamin C was used by high-performance liquid chromatography. Vitamin C was determination as an ascorbic acid. Some nutrion factors were analyzed in experimental part. There were analyzed dry matter, total flavonoids, total phenolics and titratable acid in various cultivars of apples and quinces. There were compared of some various cultivars after representation and content of significant substances as result. The last part of thesis was sensory analysis of apples.
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Studium antimikrobiálního účinku vybraných druhů koření / Study of the antimicrobial effects of selected spicesKalábová, Jana January 2013 (has links)
The antimicrobial effects of cinnamon, clove and ginger (grand and fresh) extracts against Bacillus subtilis, Aspergillus niger and Pichia fermentans were studied in this thesis. Selected spices were extracted in three solvents (ethanol, water and ethyl acetate) and inhibition effect on tested microorganisms was studied using two methods disc diffusion and broth dilution methods. The antioxidant activity and total polyphenolic compounds from spices were also determined. The results showed that cinnamon and clove extracts in ethyl acetate and ethanol were a promising antimicrobial substances for all tested microorganisms. Combination of cinnamon and clove especially ethyl acetate extracts showed an aditive effect. However, in the case of broth dilution method, fresh ginger inhibited bacterial growth under optimal growth conditions of Bacillus subtilis (35 °C, pH 7, 250 rpm). Minimum inhibitory concentration (MIC) values for all susceptible microorganisms was determined 8,3 mg/ml. The highest amounts of polyphenolic substances were found in cinnamon and clove ethanol extract and this result was in correlation with antioxidant activity.
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Výroba ovocných vín z méně známých druhůFojt, Robin January 2019 (has links)
Diploma thesis called Production of fruit wines from less known species was made at the Institute of Post-Harvest Technology of Horticultural Products. Lesser known fruit species with a focus on selected species for a practical experiment were described in the thesis, as well as the technology of fruit wine production. In the experimental part were made micro-samples of fruit wines from five species and in total in six variants. Selected quality parameters (polyphenol content, antioxidant capacity, titration acid, alcohol and residual sugar) and sensory evaluation were determined from the wines produced. All results were statistically evaluated.
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Hodnocení kvality chmele z tradiční a netradiční oblasti pěstování / Evaluation of hop quality from traditional and non-traditional region of cultivationNOVÁKOVÁ, Renata January 2016 (has links)
In this thesis, "The Evaluation of the Quality of Hops from Traditional and Non-traditional Growing Areas", the quality of three varieties of hop seed cones (Saaz, Sladek and Kazbek) from a non-traditional hop-growing region was analyzed and the data used for comparison. The primary aim of the study was to determine if there is a possibility of growing quality hops in a region that is not considered a hop-growing region. The hops that were tested were harvested in 2015 from a private hopfield located in Obora near Tábor. This hopfield is owned and managed by Ing. Martin Novák. Mechanical and chemical analysis was carried out on samples from Obora. The main goal of the analysis was to determine the alpha and beta acid content of the hop seed cones harvested there. Samples were analyzed with EBC 7.7 (HPLC). Alpha acid content of the tested samples in Saaz hops was 4.06 % w/w, in Sladek 7.14 % w/w and in Kazbek 4.67 % w/w. The content of beta acids in Saaz hops was 3.16 % w/w, in Sladek 3.93 % w/w and in Kazbek 4.51 % w/w. The collected data was then compared to published data for hops grown in traditional hop-growing regions. Alpha acid content was found to be higher in the hops grown in Obora, while beta acid content was lower.
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