To see the other types of publications on this topic, follow the link: Polyfenoles.
Dissertations / Theses on the topic 'Polyfenoles'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Polyfenoles.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Haidarian, Behroz, and Christina Lidborg. "Extraktion av polyfenoler från pressrester av röda vindruvor." Thesis, Högskolan i Borås, Institutionen Ingenjörshögskolan, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-20414.
Full textAbstract:
Antioxidanter är kemiska ämnen som är kapabla till att förhindra oxidation av andra molekyler. Dessa ämnen återfinns i djur- och växtriket och tycks ha en skyddande effekt på cellvävnad genom att motverka skadliga oxidativa reaktioner. Antioxidanter används bland annat industriellt som tillsater i livsmedel och andra produkter i syfte att förhindra oxidativ degradering och bibehålla näringsvärdet i livsmedel. I vindruvor återfinns höga koncentrationer av naturliga antioxidanter, främst i form av fenoliska ämnen. På grund av att vinindustrin bidrar till stora mänger avfall, främst i form av druvrester, är det önskevärt att hitta en effektiv metod för att återvinna fenoliska antioxidanter från avfallet.I detta arbete användes lösningsmedel-extraktion för att extrahera fenoliska ämnen från pressrester av röda vindruvor av varianten Tempranillo. Syftet var att uvärdera effekterna av extraktionsmetod, typ av lösningsmedel, extraktionstemperatur samt extraktionstid på fenol-innehåll och antioxidant aktivitet i extrakten. Två typer av extraktionsmetoder jämfördes; Soxhlet-extraktor och direkt-kontakt-extraktion (DCE), samt tre olika lösningsmedel; en blandning av etanol och vatten (1:1), ren etanol samt etyl acetat. Koncentrationen av fenoliskt innehåll i extrakten erhölls med hjälp av Folin-Ciocalteu's metod, och antioxidant aktivetet med FRAP (Ferric reducing ability of plasma) metoden.Utifrån erhållna data kunde det ses att extraktion med en blandning av etanol och vatten (1:1) som lösningsmedel gav högst fenolisk koncentration och antioxidant aktivitet för alla testade parametrar, medans etyl acetat gav de lägsta värdena. Soxhlet-extraktorn visade sig vara den bästa metoden då den gav högre värden i extrakten jämfört med DCE metoden. För DCE metoden kunde det ses att en extraktionstid på 2½ timmar vid 55 grader var mest optimalt då etanolbaserade lösningsmedel användes.Program: Högskoleingenjörsutbildning i kemiteknik
2
Critén, Sladjana. "POLYFENOLER, VITAMINER OCH PARODONTALA SJUKDOMAR - en systematisk litteraturstudie." Thesis, Malmö högskola, Odontologiska fakulteten (OD), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-19866.
Full textAbstract:
Syftet med denna systematiska litteraturöversikt var att utreda om det finns stöd i litteraturen avseende vilken betydelse kostens innehåll av polyfenoler och vitaminer kan ha för parodontala sjukdomar. Material och metod: En sökning i PubMed gjordes i mars 2012. Sökningen begränsades till humana studier på engelska och publicerade mellan januari 1990 och mars 2012. Kriterier för inkludering var: “randomized controlled trial”, “clinical controlled trial”, “clinical trial” och “”humans. Referenslistorna i de selekterade studierna granskades för att finna ytterligare studier som kunde inkluderas i analysen.Resultat: Femton studier identifierades som relevanta för syftet och som uppfyllde inklusionskriterierna. Fem av dessa behandlade polyfenolers effekt på parodontit och resultaten av dessa indikerar att polyfenoler kan påverka parodontal sjukdom. Till exempel rapporteras reducerad blödning vid sondering (BOP) och fickdjupsreducering. Fem studier studerade effekten av vitamin D. Man fann en förbättrad effekt på bennivån om vitamin D tillskottet kombinerades med kalcium. Två studier undersökte effekten av vitamin C och konstaterade att parodontal sjukdom var associerad med minskad nivå av total antioxidativ kapacitet samt med reducerad blödning. Tillskott av vitamin B – komplex resulterade i bättre läkning efter parodontal operation och multivitamintillskott resulterade i reducerad BOP och fickdjupsreducering.Slutsatsen av denna litteraturöversikt är att kunskapen avseende kostens innehåll av polyfenoler och vitaminers påverkan på parodontala sjukdomar och/eller effekten av kosttillskott på läkningen efter parodontal behandling är begränsad och att mycket forskning krävs för att några mera långtgående slutsatser kan dras.Objective of this systematic literature review was to investigate whether there is support in the literature regarding the role of dietary content of polyphenols and vitamins may have for periodontal diseases.Material and methods: A PubMed search was performed in March 2012 to identify appropriate studies. The search was limited to studies published in English between January 1990 and March 2012. For studies on the effects of polyphenols and vitamins on periodontal diseases the search was limited to studies in humans. The search was limited to: “randomized controlled trial”, “clinical controlled trial” “clinical trial” and “humans”. Additionally the reference lists of selected articles were hand searched for the possible inclusion of additional references.Results: Fifteen studies were identified as relevant to the purpose and fulfilling inclusion criteria. Five clinical studies treated the effects of polyphenols on periodontitis and results indicate that polyphenols can affect the periodontal disease. For example reduced bleeding on probing (BOP) and pocket depth (PPD) reduction was reported. Five studies were found evaluating the effect of vitamin D on periodontal disease. It was concluded that the best effect to reduce periodontal disease was observed if vitamin D supplementation was combined with calcium. Two studies looked at the effect of vitamin C on periodontitis and demonstrated that periodontal disease was associated with decreased level of the total antioxidant capacity (TAOC) and reduced bleeding on probing (BOP) after treatment with vitamin C. Vitamin B – complex supplementation resulted in improved healing after periodontal surgery and multivitamin supplements reduced BOP and PPD.Conclusion: Knowledge concerning dietary content of polyphenols and vitamins effect on periodontal diseases and/or the effect of supplements on the healing after periodontal treatment is limited and that much research is needed to some far-reaching conclusions can be drawn.
3
Dostálová, Blanka. "Stanovení celkového obsahu bílkovin, polyfenolů a sacharidů v pivu." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2016. http://www.nusl.cz/ntk/nusl-240548.
Full textAbstract:
This master‘s thesis deals with the analysis of 65 different beers, with a focus on finding differences between Czech tap ales, lagers Czech, Czech special beers and foreign beers. Czech beers were compared by the results of analysis among beers bearing the indication "Czech beer" and the group without this indication. The total amount of proteins, polyphenols and carbohydrates was determined using UV-VIS spectrometry. The history of brewing, the nature and types of Czech beers and protected geographical indication "Czech beer" were described. Raw materials for beer production and brewing technology have been listed and described. In the last part of the research, components of beer and the principle of the UV-VIS spectrometry have been specified. Th determination of total protein was performed using Hartree-Lowry method, which is based on two-component reagent. The first component is the biuret agent, the second component is the Folin-Ciocalteau reagent for phenols. Determination of the polyphenols has been carried out by the Folin-Ciocalteau reagent and total carbohydrates were determined spectrophotometrically according to the Analytica EBC using anthron agent. The results were statistically processed and evaluated in the final part.
4
Pařilová, Kateřina. "Studium vybraných aktivních látek v českém pivu." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2009. http://www.nusl.cz/ntk/nusl-216475.
Full textAbstract:
The aim of this work was to study phenolics and other active compounds in 22 kinds of lager beer and especially to find some differences between Czech beer and beers made in foreign countries. In theoretical part the most useful methods for phenolic and protein analysis are discussed. Further, basic steps of brewery technology are introduced and main beer components with regard to Czech beer specificity are presented. Analysis of total phenolics, total flavonoids, antioxidant activity and most of basic technological characteristics was performed spectrophotometrically. To identification and quantitative analysis of individual phenolics on-line liquid chromatography with photo-diode array (PDA) and mass spectrometry (MS) detection was used. Protein analysis was performed by vertical electrophoresis SDS-PAGE and by Experion microfluidic electrophoresis (BioRad). From the total of 22 samples, 15 Czech beers and 7 beers of foreign marks were enrolled into this study. In these samples levels of brewery characteristics, group antioxidants and individual phenolics were compared. Flask and can beers as well as alcoholic and non-alcoholic beers were compared too. As a model comparative sample the Czech hop of Sládek variety was used. Finally, usefulness of tested parameters to differentiation composition and technology of individual beer samples was evaluated and parameters suitable for Czech beer authenticity analysis were proposed.
5
Měřínská, Radana. "Analýza flavonoidů v pivu metodou LC-MS." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2010. http://www.nusl.cz/ntk/nusl-216608.
Full textAbstract:
Presented diploma thesis is focused on analysis of phenolic compounds in various types of beers. The aim of this work was to find possible differences among several types of beers and also between Czech beers and beers of foreign production. Theoretical part contains detailed description of beer technology, review of important analytical methods for determination of phenolic compounds and total antioxidant activity. The main attention is focused on instrumental technique LC/MS. In the experimental part values of total phenolics and total flavonoids and results of antioxidant status in analyzed beers were determined spectrophotometrically. Basic brewing characteristics were determined by pycnometry. On-line liquid chromatography with photo diode array detection and mass spectrometry detection was used for identification and quantification of individual phenolic compounds. Spectrophotometric analysis of phenolic and flavonoid levels seems to be less specific, that is consistent with findings in accessible literature. It was proved, that iso- bitter compounds exhibit about 65.44 – 90.93 % of the total bitter substances. These components are responsible for the main part of beer bitterness. The HPLC/PDA/ESI-MS was necessary to use for determination of characteristic phenolic compounds in individual types of beer. Within our measurement three columns were tested, the most favourable results were obtained using the column Restek C18. When compared with foreing beers, in Czech beers higher level of majority of phenolic compounds was detected and specific distribution of individual derivatives was found as well.
6
Omerdic, Nermina. "Syreupptag i öl vid filtrering med kiselgur." Thesis, Linnéuniversitetet, Institutionen för kemi och biomedicin (KOB), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-82520.
Full textAbstract:
Öl är en dryck som i ökande grad framställs av mindre bryggerier. För bryggarna är ett av målen att producera öl med så lång hållbarhet och en så jämn kvalitet som det är möjligt utifrån resurser, ekonomi och engagemang. En av svårigheterna vid ölbryggning är oönskad förekomst av syre efter jäsning. Syre i produkten kan förstöra ölets karaktär och ge upphov till oönskade smakämnen. Det här projektet har handlat om att mäta koncentrationen löst syre(O2) i öl efter filtrering med kiselgur och med några olika metoder försöka minimera syreupptag under filtreringsprocessen. Detta för att säkerställa god kvalitet på Nils Oscars öl. Resultatet visar på att det finns skillnad i syrekoncentrationen i alla ölsorter när metoderna med kallt- och varmt förträngningsvatten har använts samt när koldioxidgenombubblingen tillförts i kiselgurublandaren. Det skulle behöva ses över på andra delar av bryggeriprocessen för att utesluta syrekontakt med öl genom att kontrollera ventiler, rör, ledningar för att försäkra sig om att syretillförsel inte sker. Det finns också åtgärder under filtreringen som skulle behöva förbättras. Om varmare vatten används i produktionen och koldioxid tillsätts i kiselgurblandaren kommer det att minska syrekoncentrationen i filtrerad öl.Beer is a drink that increasingly is produced in smaller brewers. For the brewers the most important is to make the beer long lasting, and that requires resources, economy and commitment. Many things can go wrong when making beer, and one concern is the oxygen levels in beer that can change its taste and character and produce off flavors that are not wanted in the product. In this project the levels of oxygen was measured in the beer after filtration with kisel- gur, and using different methods attempting to minimize oxygen uptake during the filtering process to insure a good quality of Nils Oscars beer. The results showed that there are differences in oxygen levels between all beer types when using the three methods with cold- and hot water as a narrowing water and using carbon dioxide in the kiselgur mixer. It would be necessary to lock at other parts of the brewing process to exclude oxygen contact with beer. By ensuring valves, pipes and lines, quality of the equipment, and exclude any contact with oxygen. There are workarounds during filtration that can be improved. Like using hot water for a longer time. It would also need a stable and prolonged solution for induction of carbon dioxide to bubble in the kiselgur mixer. The induction of carbon dioxide has been shown to minimize oxygen pick up in filtrated beer.
7
Jelénková, Zuzana. "Stanovení aktivních látek v medu." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2008. http://www.nusl.cz/ntk/nusl-216227.
Full textAbstract:
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.
8
Trčková, Marie. "Využití metody LC/MS k analýze vybraných přírodních fyziologicky aktivních látek." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2008. http://www.nusl.cz/ntk/nusl-216232.
Full textAbstract:
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.
9
Smělá, Margita. "Stanovení některých nutričních faktorů ve vybraných druzích ovoce." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2011. http://www.nusl.cz/ntk/nusl-216776.
Full textAbstract:
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.
10
Kurzová, Pavlína. "Izolace antibakteriálních sloučenin z kávové sedliny." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2020. http://www.nusl.cz/ntk/nusl-433498.
Full textAbstract:
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.
11
Balonková, Daniela. "Vybrané alkoholové extrakty bezu černého pro využití v kosmetologii." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2019. http://www.nusl.cz/ntk/nusl-401938.
Full textAbstract:
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.
12
Jašková, Martina. "Stanovení aktivních látek v instantních nápojích určených pro dětskou výživu." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2011. http://www.nusl.cz/ntk/nusl-216755.
Full textAbstract:
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.
13
Kalábová, Jana. "Studium antimikrobiálního účinku vybraných druhů koření." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2013. http://www.nusl.cz/ntk/nusl-216977.
Full textAbstract:
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.
14
Krůzová, Sabina. "Extrakce antioxidantů z bezových květů a úchova extraktu pro další možné využití." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2018. http://www.nusl.cz/ntk/nusl-376833.
Full textAbstract:
The thesis deals with the extraction of antioxidants from elder flowers and the way of storage obtained extract. The elder flowers which are obtained by cutting trees as a waste product and after their processing it could be used as an ingredient to cosmetics products for body and face skin or in a spa like additive to baths. In theoretical part are information about black elder, its botanical characteristics, utilization and about substances contained in it. There is also a chapter about lyophilization as a method which was used for concentration of extract. The last chapter describes theoretical information about liquid chromatography because this method was used for analysis of contents of extract. Experimental part describes optimalization steps in preparation of extract. It was found that the biggest content of polyphenolic compounds was when the proportion between flower and water was 1:10, optimal temperature of water for extraction is 100 °C and it was also found that the time of extraction don´t have any influence on content of polyphenols. Thanks to the lyophilization it was obtained dry light brown powder which is stable for long time. The lyophilizate was tested for some physical properties like pH, refractive index, solubility etc. There was also determined antioxidant activity by DPPH method and there was found quenching activity is 64,9 %. In determining of heavy metals in sample was found trace amounts of lead and chrome. By liquid chromatography was determined content of polyphenols, caffeic acid was in an amount 59,6 mgl1, chlorogenic acid 398 mgl1 and ferulic acid wasn´t detected. All of analysis was for 1% solution of extract because to cosmetic it could be just this amount to addition. In the last step was prepared a skin lotion with elder flower extract and it was tested for stability also was prepared an ointment from pork lard.
15
Boberová, Jana. "Optimalizace technologie výroby echinaceových kapek." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2020. http://www.nusl.cz/ntk/nusl-433148.
Full textAbstract:
This diploma thesis deals with the production of herbal drops from Echinacea and the determination of the content of selected active substances. In the theoretical part, the taxonomic classification of echinacea, its botanical characteristics and growing conditions are mentioned. The history of cultivation and uses of this plant are also mentioned. An important chapter of the theoretical part is the chemical composition of the plant and differences in composition between individual cultivars of Echinacea. Methods for obtaining active substances and their determination are also mentioned. The last chapter is devoted to the technology of production of echinacea drops. In the experimental part, the extraction was optimized for dried flowers and roots of E. purpurea. The following extraction system was determined for the flowers: 40% ethanol, time 6 hours, weight to solvent ratio 1:10 and room temperature. For the roots, 20% ethanol and a time of 24 hours, a ratio of 1:10 and room temperature were evaluated as the best conditions. Furthermore, the best extracts were prepared, in which the content of total phenolic substances was set at 0.799-0.839 mg/ml, then the antioxidant activity was determined in the range from 116 to 242 µg T/ml, and finally the analysis of aromatic substances was performed by HS-SPME-GC-MS. Two commercial samples were also tested to compare the prepared extracts.
16
Pelikánová, Blanka. "Stanovení vybraných chemických parametrů v plodech nových odrůd rybízů." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2014. http://www.nusl.cz/ntk/nusl-217090.
Full textAbstract:
Presented diploma thesis is dedicated to the determination of selected chemical parameters of fruits of new currant varieties. The theoretical part is focused on the characteristics of currant, the biologically active substances of its fruits and also the utilization of current in the food industry. Further part of the theory deals with the main chemical parameters which were examined: polyphenols, anthocyanins, ascorbic acid and antioxidant activity. In the practical part there were determined selected chemical parameters in six white, twelve red and thirteen black varieties of currant. Anthocyanins and polyphenols have been determined spectrophotometrically. The content of ascorbic acid in selected varieties of currant was determined by HPLC. As a technique for the determinationof the antioxidant activity was selected the method of free radical DPPH.
17
Vysoká, Marie. "Vývoj energetických nápojů nového typu s obsahem přírodních aktivních složek." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2017. http://www.nusl.cz/ntk/nusl-316171.
Full textAbstract:
The aim of this thesis is the development and preparation of a new energy drink. The theoretical part of the thesis focuses on the comparison of the drinks available in market, the presentation of the main active ingredients and the proposal of enriching the new energy drink. It also describes the possibility of using an encapsulation and the method used to determine specific compound in energy drink or encapsulated particles. In the experimental part of the work, at the beginning, the main content of energy drinks were characterized, for instance caffeine, sugar, polyphenol and vitamin C. Subsequently the energy drink based on selected types of loose teas that were enriched with the encapsulated extract of acai, acerola, maca, goji and ginseng was designed. All extracts contained large amounts of polyphenols and antioxidants. In addition, acerola extracts contained very high amounts of vitamin C. Two types of particles, alginate particles and liposomes were prepared for encapsulation. For all particles, encapsulation efficiency, size, stability, and antioxidant activity were determined. Long-term stability was then monitored within three months. The particles were also exposed to artificial gastric, pancreatic and bile juice. All tested particles showed very good encapsulation efficiency. In terms of long-term storage stability in an aqueous environment. Particularly liposome particles, which also showed high stability by zeta potential measurement, were suitable. On the contrary, in case of alginate particles, when stored in an aqueous medium, the release of active substances occurred. Finally, an energy drink was created and subjected to sensory analysis. The best energy drink was based on black or green tea with alginate particles acai, goji and ginseng.
18
Konderla, Patrik. "Studium bioaktivních látek růže šípkové." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2017. http://www.nusl.cz/ntk/nusl-316235.
Full textAbstract:
Purpose of this thesis was research the content of biologically active substances in herbal rosehip extracts and also determination of antimicrobial and antioxidant activity of these extracts. Teoretical part describes informations about Rosa canina L., detailed specification of biologically active substances, specification of antioxidation and overview of methods determine antioxidant compound and antimicrobial activity. In the practical part was by combination of different solvents, procedures and herbal materials, made 21 extracts of Rosa canina L.. From measuring of these extracts, was made extraction curves and also was determined antimicrobial efficiency against bacterial strains Serratia marcescesns, Bacillus subtilis, Bacillus cereus and Micrococcus luteus. Results shows, that also all extracts has some antimicrobial activity, but only against microorganisms Micrococcus luteus and Bacillus cereus. Also was found that bud extracts contains more bioactive compounds soluble in ethanol, meanwhile rose hip extracts contains more bioactive compounds soluble in water.
19
Hilli, S. (Sari). "Carbon fractions and stocks in organic layers in boreal forest soils—impacts of climatic and nutritional conditions." Doctoral thesis, Oulun yliopisto, 2011. http://urn.fi/urn:isbn:9789514293979.
Full textAbstract:
Abstract The SOM in boreal forests contains non-living heterogeneous components resulting from microbial and chemical transformations of organic debris from plant litter. The major components in the plant biomass all decompose at different rates and therefore, contribute variably to the stable storages of soil C. The aims of the current thesis were 1) to explore how climate, soil fertility and initial litter quality affect the decomposition rate of litter, 2) to study how the different carbon fractions found in the plant litter relate to the quality and quantity of SOM in forest soils, 3) to determine whether the recalcitrant fraction of litter is derived from lignin and other polyphenols or from lipophilic compounds and carbohydrates, and 4) to determine whether the litter originating from different plant growth forms affects SOM formation in a similar way. The study was conducted in six north boreal and six south boreal study sites, half of which were mesic and half were sub-xeric. The overall initial litter quality and decomposition rate of carbon fractions did not differ between the two fertility levels and climate regimes. Litter with high initial water-soluble extractives (WSE) and nitrogen (N) decomposed at a faster rate than litter with lower initial WSE and N concentration irrespective of the soil fertility or climate conditions. Although decomposition rate varies among litter types, decomposition rate cannot explain differences in SOM quality or quantity between the northern and southern boreal forests. The organic matter accumulation and relative proportion of acid-insoluble residue (AIR) in SOM was higher in south boreal sites both in sub-xeric and mesic sites. Detailed characterization of the AIR fraction using pyrolysis-GC demonstrated that in the litter layer the concentration of AIR contains lignin and other insoluble polyphenols, but in the F and H layers, lignin-derived and chemically modified polyphenolics and decomposition products of resin acids. Although the concentration of the AIR fraction varies among litter types, its composition varied very little among the litter types, and between a sub-xeric and a mesic site. The results of this study suggest that the differences in plant community structure and quantitative differences in the litter input by various growth forms has more impact on OM accumulation than decomposition conditions in coniferous soilsTiivistelmä Metsämaan orgaaninen aines koostuu eriasteisesti hajonneesta karikkeesta sekä pitkälle maatuneesta, hajottajien muokkaamasta humuksesta. Tutkimuksessa selvitettiin 1) kuinka ilmasto, maaperän ravinteisuus ja karikkeen kemialliset ominaisuudet vaikuttavat karikkeen hajoamisnopeuteen, 2) kuinka kasvien sisältämät erilaiset hiilifraktiot vaikuttavat maaperän orgaanisen aineen laatuun ja määrään, 3) millaiset hiiliyhdisteet muodostavat vaikeimmin hajoavan hiilifraktion karikkeessa ja pidemmälle maatuneessa orgaanisessa aineessa ja 4) onko erilaisten kasvien vaikutus orgaanisen aineksen muodostumiseen samanlainen kuusikoissa ja männiköissä pohjois- ja eteläboreaalisella havumetsävyöhykkeellä. Tutkimuksessa havaittiin, että karikkeen maatumisnopeudessa ei ollut eroja pohjois- ja eteläboreaalisella kasvuvyöhykkeellä eikä kuusikoiden ja männiköiden väillä. Karike, joka sisälsi runsaasti vesiliukoisia yhdisteitä ja typpeä maatui nopeammin kuin vähän vesiliukoisia yhdisteitä tai typpeä sisältävä karike. Karikkeen maatumisnopeus ei kuitenkaan kyennyt selittämään eroja pidemmälle maatuneen orgaanisen aineksen määrässä ja laadussa pohjois- ja eteläboreaalisella kasvuvyöhykkeellä. Orgaanisen aineksen määrä oli suurempi eteläboreaalisella kasvuvyöhykkeellä verrattuna pohjoisboreaaliseen. Lisäksi vaikeasti hajoavia hiiliyhdisteitä (AIR-fraktio) kertyi eteläboreaaliseen metsämaahan enemmän kuin pohjoiseen. Karikekerroksessa ligniini ja polyfenolit muodostivat suuren osan AIR-fraktiosta. Maatumisen edetessä AIR-fraktion muodostavat lähinnä ligniinin hajoamisesta peräisin olevat ja muut modifioituneet polyfenolit sekä pihkahappojen hajoamistuotteet. Vaikka AIR-fraktion konsentraatio vaihteli kariketyypeittäin, sen kemiallinen koostumus oli hyvin samanlainen karikelajista riippumatta. Tutkimuksen perusteella vallitseva kasvillisuus ja sen tuottaman karikkeen määrä ja laatu vaikuttavat enemmän metsämaahan kertyvän orgaanisen aineen määrään kuin maatumisolosuhteet
20
Tomková, Martina. "Obsah antioxidačních látek ve vybraných druzích ovocných a bylinných čajů." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2008. http://www.nusl.cz/ntk/nusl-216228.
Full textAbstract:
This diploma project deals with antioxidant and antimutagenic properties of selected herbal and fruit teas commonly used in Czech population. Influence of different tea packaging (bag teas and loose leaf teas) on bioactive compound content was compared. Further, effect of long-term storage in common household conditions was studied. Antioxidant properties of teas were characterized using some group parameters - total antioxidant activity ("Randox Total Antioxidant Status Kit"), total phenolics and total flavonoids - as well as some individual representatives of low molecular weight antioxidants. Higher antixidant content was found in herbal teas than in fruit teas. Comparing bag teas with loose leaf teas higher antioxidant activity was shown in loose leaf teas. Individual antioxidants were analyzed using HPLC method with spectrophotometric detection and verified by on-line LC/MS. IN all tea samples catechins - catechin, epicatechin, epicatechin gallate and other flavonoids - rutin, morin, quercetin, kaempferol, myricetin and luteolin were determined. In most of teas high level of catechin and rutin was detected. The highest level of flavonoids was determined in herbal poured teas. Ascorbic acid content was also determined by HPLC method. Higher vitamine C level was found in most of fruit teas and in rose hip tea. Antimutagenicity of tea extracts was tested by in vitro test using Saccharomyces cerevisiae D7 yeast. High antimutagenic activity showed mainly nettle tea, tutsan tea and most of fruit teas. During long-term storage (1 year, 20°C, darkness) a significant decrease of all analyzed antioxidant parameters was followed. Higher lost of antioxidants was found in fruit teas when compared with the herbal ones.
21
Jančíková, Simona. "Charakterizace jedlých obalů pro potenciální použití při balení potravin." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2019. http://www.nusl.cz/ntk/nusl-401908.
Full textAbstract:
In the last years, the edible packaging has been gaining popularity due to the potential usage as the packaging for food instead of synthetic materials. The edible packaging can positively affect the packaged food by the active properties or due to its intelligent properties can monitor the changes in food. In theory, the legislation about the packaging of food and edible packaging was described. The substances for edible films preparation and additives, which can improve the properties of the edible films, were described too. In this part, the undesirable microorganisms occur in food and the chapters about active and intelligent properties of the edible films were summarized. The main aim of the thesis was the practical preparation of edible packaging/films made from furcellaran, gelatin hydrolysate with the addition of water dried or fresh rosemary extracts in concentrations 5 %, 10 %, and 20 %. In the experimental part, the physical analysis was done – textural parameters such as tensile strength and elongation at break, water content, and thickness. In the chemical analysis the total polyphenols content, determination of polyphenols by HPLC, antioxidant activity, optical properties and antimicrobial activity of the prepared edible films were done. There were found out, that the total polyphenols content and antioxidant activity were the highest in the 20%DR (TPC: 6,79 ± 0,06 mg gallic acid/g; DPPH: 87,84 ± 0,07 %). Also, the 20%DR and 20%FR changed color in different pH (3 and 12). The antimicrobial activity was negative. The thesis showed that the addition of natural extracts to edible films can increase the polyphenols content and they can also work as the UV protector.
22
Tomíšek, Martin. "Charakterizace rostlinné složky vybraných potravin pomocí technik molekulární biologie a instrumentálních metod." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2020. http://www.nusl.cz/ntk/nusl-432719.
Full textAbstract:
The aim of this work was to compare authenticity analysis in selected food products with fruit component by using, instrumental and molekular methods. Particularly, the presence of blueberries in fruit–based foodstuffs was verified. The theoretical part is focused on the characterization, chemical composition and botanical classification of blueberries (European blueberry and Canadian blueberry). It also contains an overview of instrumental and molecular diagnostic methods that can be used for the analysis of these fruits. The experimental part focuses on the selection of a suitable method of DNA isolation, and primers for the detection of blueberries in commercial products. DNA analysis was performed by qPCR and HRM analysis. In the experimental part, DNA was isolated in sufficient quality for PCR and the presence of blueberries in foodstuffs was verified by qPCR. Using HRM analysis, we were able to differentiate between bilberry (Vaccinium myrtillus) and blueberry (Vaccinium corymbosum) in control samples and in some commercial products. Certain phenolic acids and some flavonoids specific for blueberries were detected by HPLC. The total content of polyphenols and flavonoids was determined by UV / VIS spectrophotometry.
23
Ďubašáková, Mária. "Bioaktivní látky růže šípkové." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2018. http://www.nusl.cz/ntk/nusl-376829.
Full textAbstract:
The aim of this master´s thesis was to determine the concentration of bioactive substances such as total polyphenols and flavonoids as well as the total antioxidant capacity in tea extracts from Rosa canina. In the second part, an experiment was found to detect antimicrobial activity and an effective concentration of ethanol against selected bacteria. The theoretical part is focused on description of natural antioxidants and their effect on free radicals, description of tea, description of rose hazel and possibilities of spectrophotometric determination of natural substances and eventually basic distribution of bacteria. In the experimental part, ethanol and aqueous extracts were prepared in which the total number of polyphenols, flavonoids and antioxidant effects. The results of the determination of polyphenols and flavonoids show that the solvent with ethanol is more suitable for flower fermentation and water is more suitable for dropping the rose. Comparison of the antioxidant activity of macerates showed no significant differences; slightly higher antioxidant activity showed macerates from pink flowers. The extracts showed antimicrobial activity against Micrococcus luteus and slightly against Bacillus cereus. The highest antimicrobial activity was determined for the micrococcus luteus
24
Javorská, Kateřina. "Stanovení vybraných chemických parametrů plodů moderních odrůd angreštů." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2014. http://www.nusl.cz/ntk/nusl-217081.
Full textAbstract:
Diploma thesis deals with determination of individual chemical parameters contained in modern varietes of gooseberries (Grossularia uva-crispa). The theoretical part is focused on the botanical characteristics of the plant, a description of selected varietes, chemical composition and food utilization fruits. The second half of the theoretical part is devoted to the characterization of selected nutritional parameters and methods for determination of total anthocyanins, phenolic compounds, vitamin C and antioxidant activity. Total of 17 varietes of gooseberries, which come from growers Vondráček and the Research and Breeding Institute of Pomology Holovousy Ltd. were analyzed in the experimental part. pH differential method was used to determination total monomeric anthocyanins. Total content of polyphenols were determined by using the Folin-Ciocalteu reagent. Next was determined content of vitamin C in all varieties by HPLC and was evaluated the total antioxidant aktivity using radical DPPH. In conclusion, individual varieties of gooseberries were compared by the contents of the determined chemical parameters.
25
Matějková, Markéta. "Sledování změn vybraných druhů lokálního ovoce v průběhu mražení." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2011. http://www.nusl.cz/ntk/nusl-216759.
Full textAbstract:
This diploma thesis was focused on study of low-molecular antioxidants present in various kinds of fruits, namely berries. In theoretical part detailed characterization of antioxidants studied in presented work and their biological effects are introduced. Further, principals of processing and storage of specified species of fruits are discussed. Changes observed during storage of specific fruits are described too. In practical part changes in content of selected antioxidants in berries were followed. As studied material strawberries, raspberries, blueberries, red and black currants were used. All kind of these fruits was stored in fridge for six months using several different kind of processing. Berries were stored as whole fruits, whole osmotically processed fruits by sucrose, raw pulp and sweetened pulp. At first, starting values of selected antioxidant parameters were measured in fresh fruits (ascorbate, total antioxidant activity, total phenolics, catechins and individual flavonoids). After freezing the same parameters were measured regularly in two month periods. As the most suitable method of fruit processing, with regard to antioxidant content, storage of the whole fruits or pulp can be recommended. Content of ascorbate decreased in all forms and species of the processed fruits during all the time of storage. Oppositely, the content of other studied antioxidants exhibited fluctuations or increasing trend. Sensory analysis was proved for the whole fruits and also for whole sweetened fruits.
26
Juráňová, Jana. "Stanovení vybraných nutričních faktorů v některých druzích minoritního ovoce." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2013. http://www.nusl.cz/ntk/nusl-216913.
Full textAbstract:
The theme of this diploma thesis is an assessment of given nutritional parameters in selected kinds of lesser known fruits, specifically 10 varieties of sea buckthorn (Hippophae rhamnoides L.), 12 varieties of cornelian cherry (Cornus mas L.) and 6 varieties of blue honeysuckle (Lonicera caerulea var. kamtschatica). Harvests of two consecutive years (2011 and 2012) were analyzed in the case of blue honeysuckle. The theoretical part was focused on historical, morphological, taxonomic and nutritional aspects of individual plants and food or pharmaceutical utilization. The considerable part of the thesis is devoted to the characterization and the possibilities of determining the contained substances, namely ascorbic acid and polyphenolic compounds, especially anthocyanins. The content of the experimental part was a description of the methods and the results of the analysis of total solids, titratable acidity, total phenolics, total anthocyanins and ascorbic acid in fruits of the selected varieties of the above mentioned fruit species. Based on the measured results, the different varieties of fruits were compared to each other and evaluated.
27
Vejrostová, Petra. "Studium směsných přírodních antimikrobiálních preparátů a možnosti jejich stabilizace." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2016. http://www.nusl.cz/ntk/nusl-240734.
Full textAbstract:
Present diploma thesis is focused on natural antimicrobial substances. The aim of the experimental part of thesis was testing of antimicrobial activity of selected natural substances in free and encapsulated forms, preparation of particles and monitoring of their long-term stability. Various teas extracts (aqueous, ethanoic and DMSO) and aqueous herbs extracts were used as plant antimicrobial substances. Liposomes and chitosan particles with encapsulated aqueous teas extracts were prepared by ultrasonication. Encapsulation efficiency, size, stability and antioxidant activity for all particles were specified. Consequently, within a two months period, long-term stability for these particles was monitored. Spectrophotometric method for determining total polyphenols was used for evaluating encapsulation efficiency as well as for monitoring of long-term stability. The DLS method was used for determination of size and stability of particles. Antioxidation activity was monitored by using spectrophotometric method using ABTS. For testing antimicrobial activity of various types of teas, herbs extracts and their mixtures and combianitons with lysozyme and antibiotics, broth dilution methods were used while using both Gram positive and Gram negative bacterial test strains. Antimicrobial activity of prepared particles was also monitored, the antimicrobial activity was especially significant with the chitosan particles. Suitable combinations of natural substances whatever with antimicrobial or antioxidation effect either in free or encapsulated form could be used for applications for example in cosmetics industry, food processing or in medicine.
28
Cetkovská, Jitka. "Zhodnocení fyzikálních a chemických parametrů plodů dosud méně využívaných druhů drobného ovoce a návrh nového nealkoholického nápoje z tohoto ovoce." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2016. http://www.nusl.cz/ntk/nusl-263387.
Full textAbstract:
This thesis deals with still less expolited species of small fruit, evaluation of its physical and chemical parameters and proposal of a new soft drink from one of the studied species of furit. Firstly, for the characterisation of basic nutrition parameters (dry matter, content of organic acids and saccharides) and biologicaly active substances (vitamin C, anthocyanins and phenolic compounds) suitable titration, spectrophotometric, chromatographic and electrophoretic methods were chosen, optimized and validated. The sample preparation procedure was optimized as well. For three years (2010–2012) the content of listed parameters was monitored in some cultivars of five species of small fruit: in seven cultivars of sea buckthorn, in ten cultivars of cornelian cherry, in twelve cultivars of rowanberry, in two cultivars of chokeberry and in seventeen cultivars of elderberry. By means of Duncan’s test, analysis of principal components (PCA) and cluster analysis (CLU) the main differences between studied cultivars were observed mainly in sea buckthorn and rowanberry, where single cultivars were easily distinguishable from others on the basis of genetic origin. On the basis of comparison of determined parameters in studied species of fruit and with collaboration with fruit processing company the suitable species of fruit for commercial utilization was chosen – elderberry, as a important source of anthocyanins and phenolic compounds. A new soft drink as a proposal of utilization of this fruit was created – fruit juice or nectar with portion of elderberry juice. Mixed juices and nectars with various composition were prepared from elderberry and grape juice and the sensory analysis of these drinks was performed. The best evaluated were 100% fruit juices prepared with 30–50% portion of elderberry juice. The composition was jurally protected. On the basis of this protection the product consisted from 100% fruit juice with 10% of elderberry component mixed with apple and grape juice was introduced to the market by the fruit processing company.
29
Vacková, Hana. "Studium biologických účinků technického konopí a jeho frakcí." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2017. http://www.nusl.cz/ntk/nusl-316189.
Full textAbstract:
Cannabis is the only plant which contains cannabinoids and thanks to these compounds it has enormous potential. This thesis deals with the analysis of technical hemp. Effects of cannabinoids and methods used for cannabis analysis are discussed in the theoretical part. The experimental part includes spectrophotometric characterization of cannabis, it´s antimicrobial effects and thin layer chromatography analysis. Three sorts of Cannabis sativa L. were analyzed, namely Finola, Fedora and Kompolti. Firstly, the content of polyphenols, flavonoids and antioxidant activity in prepared tinctures were determined. Moreover, antimicrobial test were performed using disk test and turbidity determination. Gram-positive and Gram-negative bacteria and yeast organism were tested. It was found that cannabis tinctures possess good antimicrobial effects. Some of them are comparable with synthetic antibiotics. Finally, thin layer chromatography enabled visualization of cannabinoids in prepared tinctures.
30
Štindlová, Jitka. "Možnosti enkapsulace přírodních antioxidantů." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2012. http://www.nusl.cz/ntk/nusl-216837.
Full textAbstract:
In theoretical part of this diploma thesis the basic properties of antioxidants, especially anthocyanins and phenolic compounds are described, as well as the basic features and principles of free radicals formation. The theoretical part also describes some possible ways of encapsulation of antioxidants into polysaccharide and lipid particles. In the experimental part basic characteristics of extracts from selected lyophilized fruits and vegetables (carrots, apples and mixed berries) are described. As group parameters of plant extracts the total antioxidant activity, content of flavonoids and phenolics, carotenoids, anthocyanins and ascorbic acid were determined. In experimental part also various encapsulation techniques were tested, encapsulation effectiveness of each technique was evaluated and the stability and size of the created particles were determined. As the best encapsulation method in terms of encapsulation efficiency in most of samples/parameters ethanol injection was found. On the other hand the particles prepared by ethanol injection are relatively unstable in terms of zeta potential, which is followed by their tendency to aggregate. As the most stable particles prepared by thin layer evaporation (TLE) and reverse phase thin layer evaporation (RP-TLE) were evaluated. Particles prepared by TLE, RP-TLE and chitosan-alginate particles exhibited a negative charge, while particles prepared by ethanol injection stayed uncharged and chitosan particles have a positive charge.
31
Veselý, Ondřej. "Srovnání plodů některých odrůd zimolezů z hlediska obsahu vybraných biologicky aktivních látek." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2015. http://www.nusl.cz/ntk/nusl-217113.
Full textAbstract:
This thesis is focused to the analysis of selected varieties of honeysuckle kamtschatica (Lonicera caerula var kamtschatica) and their comparison in terms of the content of biologically active substances. There were analysed only varieties grown in 2014. Theoretical part elaborates and characterized various parameters of biologically active compounds such as phenolic, anthocyanins and ascorbic acid and possibilities of their determination. Further it briefly surveys Kamchatka honeysuckle, its taxonomic and morphological properties and its nutritional properties. The experimental part of the work was focused on the description of the methods used for the analysis of biologically active substances and their analysis. Polyphenolic compounds and anthocyanin’s were determined spectrophotometrically and vitamin C was determined by high-performance liquid chromatography. The results and varieties were compared with each other. Overall, we can say that the variety with the highest content of all three analysed biologically active substances is a variety Valchová, which had the second highest content of polyphenolic compounds (546.3 mg · 100 g-1 fruits), the third highest contend of ascorbic acid (35.1 mg · 100 g-1 fruits) and the sixth highest content of anthocyanin (170.8 mg · 100 g-1 fruits)
32
Plášková, Anna. "Stanovení autenticity potravin rostlinného původu pomocí molekulárních metod." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2020. http://www.nusl.cz/ntk/nusl-433058.
Full textAbstract:
The aim of presented diploma thesis was to determination of authenticity of fruit baby foods for early infant feeding using molecular methods. In the experimental part, isolation kit was used for isolation of plant DNA from fruits (strawberry, apricot, raspberry, apple) and from six commercial fruit products for children. Isolated DNA was characterized and verified using PCR methods with primers specific for plant rDNA (ITS2). Specific primer pairs were designed to amplify DNA for the detection of one fruit species. Primer specificity was assessed with four fruit species. A mixture of fruit puree from the two fruits was used to determine the sensitivity of the multiplex PCR assay. Six commercial fruit products were evaluated to verify the applicability of the multiplex PCR assay. The methodology of molecular detection of fruit DNA by qPCR and multiplex qPCR (duplex) includes approaches, which enable to detect two fruits (strawberry-raspberry, apricot-apple) in one reaction and thus reduces time and money requirements.
33
Hájková, Tereza. "Přírodní látky v léčbě rakoviny a jejich cytotoxicita." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220049.
Full textAbstract:
The thesis deals with the natural substances in context with the cancer disease. The natural substances have a positive effect on the human organism and they are able to influence the viability and the growth of the cancer cells. The main mechanical device is to influence the mechanisms needed to start the apoptosis of the cancer cells and stopping further proliferation. The cancer cell lines utilization in the cancer disease is discussed in the thesis too. The thesis states common methods of determining the natural substances cytotoxicity. For the experimental part of the thesis it was chosen the MTT test method and the xCELLigence system for monitoring in real time. The mechanical device of the tested substance capsaicin in application on the prostate cell lines, tumorous PC3 and nontumorous PNT1A influence will be observed within the experimental part of the thesis.
34
Jurečková, Zuzana. "Charakterizace odrůd minoritního ovoce z hlediska využití v potravinářském průmyslu." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2021. http://www.nusl.cz/ntk/nusl-438509.
Full textAbstract:
The thesis deals with one group of small fruits, the genus Ribes, ie currants, and gooseberries. It assesses their physical and chemical parameters with respect to the possibility of use in these properties for the design of a new type of product – beverages. Titration, spectrometric and other methods were used for the evaluation of these properties. A total of fifteen of these methods were available (total juice yield, juice pH, total dry matter, soluble fruit dry matter, titratable acidity, formolic number, reducing carbohydrate content, D-glucose, D-fructose and sucrose content, total polyphenolic substance content, anthocyanins, vitamin C and total antioxidant capacity) and a total of nine analytes (copper, iron, magnesium, phosphorus, zinc, manganese, potassium, calcium and sodium) were selected for the determination of mineral elements. For two years (harvest 2014 and 2015), these parameters were monitored for color variants of currants (white, red and black) and gooseberries (green-fruited, yellow-fruited and red-fruited). A total of six white varieties were tested in the group of currants - Olin, Jantar, Primus, Blanka, Viktoria and Orion, eleven varieties of red currants - Junnifer, Jesan, Detvan, Rovada, Rubigo, J.V.Tets, Tatran, Losan, Kozolupský raný, Stanca, NŠLS 11/6 and eleven varieties of black currant varieties - Ometa, Démon, Triton, Ben Hope, Ruben, Ben Gairm, Ben Lomond, Moravia, Ben Conan, Fokus and Ceres. A total of five varieties of green-fruited gooseberries were tested - Zebín, Mucurines, Rixanta, Rodnik and Prima. Yellow-fruited gooseberries were available in four varieties - Lemon Giant, Invicta, Golden Fig and Darek. The red-fruited gooseberries included varieties - Rolonda, Alan, Karat, Karmen, Krasnoslawjanskij, Himnomacki Rot, Remarka, Tamara and Black Neguš. Using Tukey's test, an analysis was performed and by scoring individual varieties based on the results of individual analyzes, a list of recommended varieties was compiled for further work on the development of a new beverage. Unfortunately, in 2015 there were very few fruits of green-fruited and yellow-fruited gooseberries, so it was decided that the volume of fruit will fall on the testing of bioactive substances. Therefore, at the end of the work, it is not possible to objectively evaluate these varieties of gooseberries in the whole range of analyzes. Therefore, the point evaluation of varieties was based on the averages of individual varieties. The red-fruited varieties were available in full, and therefore a full evaluation could take place. The most significant differences between red gooseberry varieties were in the content of bioactive substances (the content of polyphenolic substances, anthocyanin dyes, and vitamin C) and antioxidant capacity. These results were provided to the food subject, which continued to work with these values. Based on this project, utility model No. PUV 2016-33171 and the resulting combined drink based on wine and fruit juice were developed.
35
Al, Hariri Raeed. "Olive pruning frequency and mechanization of harvesting: effects on vegetative-reproductive growth,physiology of the trees and oil quality." Doctoral thesis, 2017. http://hdl.handle.net/2158/1080536.
Full textAbstract:
Three trials were carried in order to acquire new knowledge useful for an optimization of olive pruning and mechanization of olive harvesting and for a better understanding of olive floral/fruiting biology.
36
Skarková, Anežka. "Screening polyfenolů v kávě." Master's thesis, 2019. http://www.nusl.cz/ntk/nusl-427648.
Full textAbstract:
The thesis entitled Screening of Polyphenols in Coffee deals with origins and attri-butes of particular types and technologies of coffee making.The theoretical section focuses on occurance and importance of biologically active compounds contained in coffee that might have both positive and negative impact on human´s health. I also mention the legislation related to the issue of defining and labeling the coffee. Regarding the most current lifestyle diseases and various social groups I describe the general influence of coffee on human´s health and the most common methods of determination polyphenols in food.In the practical part I use the High-performance liquid chromatography to identify the spectrum and amount polyphenolic com-pounds at selected samples of coffee of various geographical origin. Overall I tested samples of 10 roasted and 8 unroasted Arabica coffee and 2 samples of Robusta coffee.
37
Kondrashov, Alexey. "Biochemie účinků polyfenolů v léčbě vaskulárních onemocnění." Doctoral thesis, 2011. http://www.nusl.cz/ntk/nusl-297732.
Full textAbstract:
This Ph.D. thesis deals with the deep analysis of polyphenols effects toward vascular disorders. This work provides a number of experimental results of studying both the effects of natural bioactive compounds in red wines and potatoes, and their application to the experiments which includes experimental animal models with spontaneous hypertension. Methods and equipment used in experimental studies allowed us to make several new statements regarding the universal nature of the relationships between the antioxidant capacity and the polyphenolic content in examined foodstuffs. Besides this it is also recognized that food is a source of minerals which also contribute to the total antioxidant capacity and therefore may have influence the endogenous antioxidant enzyme system by providing the essential cofactors. Experimentally we have found that the concentrations of magnesium known for its therapeutic action in wine and red wine extract are comparable to the mineral waters recommended for the treatment and prevention of cardiovascular and metabolic diseases. Moreover, synergistic interactions between selected minerals have been found. The key issue of bioavailability of polyphenols for supporting the idea of the beneficial effects of diet rich in fruits and vegetables toward vascular disease prevention...
38
Vyhnálek, Petr. "Screening antiradikálové aktivity drog s obsahem polyfenolů." Master's thesis, 2007. http://www.nusl.cz/ntk/nusl-287634.
Full text
39
Kvita, Vojtěch. "Účinek polyfenolů ze zeleného čaje na antioxidační enzymy u myší in vivo." Master's thesis, 2014. http://www.nusl.cz/ntk/nusl-339208.
Full textAbstract:
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Vojtěch Kvita Supervisor: PharmDr. Hana Bártíková, Ph.D. Title of diploma thesis: The effect of green tea polyphenols on antioxidant enzymes in mice in vivo Antioxidant enzymes belong to compounds with proven effects on human organism. Their main purpose is to defend cells against oxidative stress. In order to support this process, we are taking substances called antioxidants either in regular diet or as dietary supplements. Recently there are a lot of companies on the market, offering the supplement, promising wight loss or defence against cancer. Green tea contains many natural substances, such as polyphenolic compounds which include catechins, which have proven effects on our bodies, but the specific way they act on selected antioxidant enzymes is still matter of study. The aim of this work was to determine the effect of green tea polyphenols on antioxidant enzymes in mice. We studied 8 groups (4 normal, obese 4) wherein the two groups were left as a control which means without administration of Polyphenon. Three groups were given a Polyphenon enriched diet and for various period of time (28 days, 3 days) and at different concentrations (0.1%, 0.01%). Activity was studied in liver...
40
Prokopcová, Zdeňka. "Variabilita kyseliny ferulové v odlišných odrůdách ječmene." Master's thesis, 2010. http://www.nusl.cz/ntk/nusl-87967.
Full text
41
Kubicová, Marta. "Analýza vybraných polyfenolických látek v pivu technikou HPLC." Master's thesis, 2007. http://www.nusl.cz/ntk/nusl-92574.
Full text
42
Čížek, Milan. "Možnosti zvýšení obsahu nutričně významných látek v bramborách." Doctoral thesis, 2009. http://www.nusl.cz/ntk/nusl-93619.
Full text
43
Strejčková, Aneta. "Biologicky aktivní látky v medu." Master's thesis, 2015. http://www.nusl.cz/ntk/nusl-250232.
Full textAbstract:
This thesis is concerned with biologically active substances in honey. The first part describes the characteristics of honey, its origin and its composition. It also deals with the polyphenols and importance of honey on human health. Polyphenols are the subject of many studies and was therefore chosen as representatives of the major biologically active substances. It describes their characteristics and representations of honey. The second part deals with the determination of polyphenols. For this purpose were selected 14 phenolic acids, which was determined in 8 kinds of honey. Analysis was performed by liquid chromatography mass spectrometry (HPLC-MS). Extraction was carried out by extraction by liquid-liquid and solid-phase extraction using two solvents, diethylether and ethylacetate. These methods were then statistically compared. The results show that the highest average content of phenolic acids was in honey pine honeydew and honeydew mixed. Generally, honeys contain most p-coumaric acid.
44
Žákovič, Peter. "Využití nanovlákenných struktur ve filtraci." Master's thesis, 2019. http://www.nusl.cz/ntk/nusl-426626.
Full textAbstract:
In this diploma thesis, we focused on the filtration of wine, the type of filtration and the filtration methods currently used in the literary section. Further, filtration materials, which are used in wine filtration and, last but not least, the use of nanoparticles in viticulture and winemaking, have been described. In the practical part, commercial filter types were used, namely Cartridge filter C11 with nanofibrous filter membrane RIFTELEN N15-2 and RIFTELEN N15-5, which we compared with the Zambelli plate filter, in which we used filter plates HOBRAFILT S15N and HOBRAFILT S30N. In particular, we compared the content of free and total sulfur dioxide, wine turbidity, protein turbidity and polyphenols in wine. From each type of unfiltered and filtered wine, we put the samples in bottles of 750 ml and left overnight in the cellar. The next day we analytically measured each variant sample. All results were then statistically processed and evaluated with recommendations for practice and further investigation.
45
Petráň, David. "Stanovení koloidní stability u vybraných druhů piv." Master's thesis, 2014. http://www.nusl.cz/ntk/nusl-179618.
Full textAbstract:
Unlike majority of sorts of alcoholic drinks beer is considered significantly un-stable. This thesis examines the factors influencing the stability of beer, especially phys-ical-chemical, primarily content of polyphenols and potential of components of beer to form haze. Twenty eight samples from differently large breweries were processed (Černá Hora, Poutník Pelhřimov, Pegas, Richard and minibrewery of Mendel University in Brno). The total content of polyphenols was determined using the Folin-Ciocalteu method (spectrophotometrically at 750 nm) and subsequently expressed in the content of ferulic acid, which served as a standard for purposes of this study. The average con-tent of polyphenols was in Černá Hora Sklepní 338,5 mg.l-1, in light lager beer Poutník 370 mg.l-1, in light lager beer Pegas 694,5 mg.l-1, in light lager beer Richard 726,3 mg.l-1, in wheat beer from Mendel University in Brno 562 mg.l-1 and in Rauch from Mendel University in Brno 817 mg.l-1. Turbidity of beer for consumption and potential of beer components to form haze using EBC test was also assessed. Both types of turbidity were measured by turbi-dimeter at 620 nm using Helm BaSO4 standard and based on the measured values were compared with the established range of haze. Finally, the results were discussed and assessed physical-chemical stability of observed beers.
46
Deutscharová, Jitka. "Obohacené nápoje na bázi vína." Master's thesis, 2014. http://www.nusl.cz/ntk/nusl-190282.
Full textAbstract:
This thesis was prepared at the Institute of Post-Harvest Technologies of Horticulture at the Faculty of Horticulture of the Mendel University in Brno in years 2012/2014. The aim of this thesis was to elaborate on the nutritional constitution of wines with emphasis on phenolic components, to deal with methods of determination of the antioxidant activity and to compile the legislative requirements relevant to selected wines. In the experimental part, wine-based beverages with the addition of wood chips or their extracts were designed and prepared. Subsequently, selected quality parameters of the prepared beverages were compared and the prospects of their success in the market place were evaluated.
47
Pelcová, Lucie. "Stanovení přírodních antioxidantů v ovocných džusech." Master's thesis, 2016. http://www.nusl.cz/ntk/nusl-362639.
Full textAbstract:
The objective of this thesis was to investigate the content of polyphenols in these juices: apple from concentrate, apple produced by direct compression, orange with pulp, orange without pulp, grapefruit from concentrate, juice from red grapes, pomegranate and purple carrots. The measurement was taken by high performance liquid chromatography and mass spectrometry. The polyphenol with the highest overall value and also the most important of polyphenols in citrus juices was hesperidin. Significant content of cryptochlorogenic acid and hyperoside was in apple juice. Apple juice produced by direct compression also contained a lot of catechin. Epigallocatechin, epicatechin and gallic acid were substances with the highest value measured in the juice of the pomegranate. Catechin, epicatechin and epigallocatechin were most prevalent in the grape juice. Quantitatively the most important compounds of juice from purple carrots were caffeic and cryptochlorogenic acid.
48
Šajtarová, Pavla. "Použití polyvinylpolypyrrolidonu a možnosti jeho regenerace v nápojovém průmyslu." Master's thesis, 2016. http://www.nusl.cz/ntk/nusl-363264.
Full textAbstract:
This diploma thesis is focused on the topic The use of polyvinylpolypyrrolidone and possibilities of its regeneration in the beverage industry. The thesis was written in years 2015/2016 at the Department of Post-Harvest Technology of Horticultural Products, Faculty of Horticulture at Mendel University in Brno. The theoretical part deals with the polyphenolics compounds in wine, antioxidant capacity and wine defects related to polyphenols. The last chapter offers multiple methods of removing defects, where the highest priority is given to the clarifier PVPP. The experimental part is aimed at the regeneration of single used PVPP with four different ways and the determination of its efficiency throughout suitable analyses after its reuse in the wine. The resulting data are statistically processed and shown in the graphs.
49
Džuppa, Mikuláš. "Štúdium antioxidačných vlastností čajov." Master's thesis, 2019. http://www.nusl.cz/ntk/nusl-426532.
Full textAbstract:
The Diploma Thesis is focused on the analysis of the antioxidant qualities and attributes of different kinds of tea under their specific methods of preparation. Literature overview provides history, processing technology, distribution and the most common means of tea preparation as well as its content substances. The Thesis discusses the overall containment of polyphenols and antioxidant capacity based on the FRAP and DPPH methods but also the amount of vitamin C in the tea samples. The Thesis elaborates on the undertaken sensor analysis of chosen samples and examines the tea content substances during its traditional preparation as well as during its preparation in a non-typical way.
50
Ošťádalová, Ilona. "Metabolický profil biologicky významných látek v medu." Master's thesis, 2017. http://www.nusl.cz/ntk/nusl-430290.
Full textAbstract:
This thesis is introducing us theme of the metabolic profile of biologically important compounds in honey. This thesis is devided into two parts. The first part (the literature review) is introducing characteristic of honey, history of a use for medical purposes, honey content, content of biologically active compounds and their positive effects on human health. There are also described methods of determination polyfenolic compounds in honey. The second part of this thesis (practical part) deals with determination of polyfenols in 11 kinds of honey using the high pressure liquid chromatography mass spectrometry (HPLC-MS). Extraction was carried out by using liquid-liguid extraction using ethylacetate and diethylether as a solvent and solid phase extraction using water as a solvent. These methods were then statistically compared.