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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Možnost dalšího využití bezinkových výlisků / Possibility of further use of elderberry marc

Sedláčková, Lucie January 2019 (has links)
This Diploma thesis talks about the production of concentrates and lyophilisate from the extract of elderberry moldlings (elderberry, Sambuvus nigra L.) and by determination by chosen chemical characteristics of these products. The theoretical part includes the botanical characteristics of the plant species Sambucus nigra L. Next is the part that is dedicated to biologicaly active substances found in elderberry and it‘s possible usage in the food industry. Next is the part where the extraction, purification and indentification of anthocyanic dyes are described. In the next part is the analyrical method HPLC described, including the description of instrumentation. The last part talks about the description of the used methods: methods for the concentration of the extract, UV-VIS spectrophotometry, determination of phenolic compounds, determination of dry matter, determination of active acidity and the overall titrating acidity. The experimental part contained the optimalization of the process of producing the extract from elderberry moldings. The extract obtained was then concentrated for preservation and characterization purposes based on selected chemical properties. The total content of anthocyanin dyes was chosen as a quality parameter. The most suitable process for the preparation of the extract was chosen to be the ratio of moldings and solvent 1:2, 4 (m/V). The most suitable solvent was chosen to be a mixture of water and ethanol in a ratio of 1:1 (V/V). According to the needs of the submitter, an extract with the use of water as the extraction agent is also provided. The prepared extract was then concentrated on a vacuum evaporator or lyophilized for storage purposes. The dye degradation while using the evaporator was the lowest in a 40 ° C water bath. The final products were characterized by the determination of soluble solids, pH, titration acidity, total phenolic compounds and total anthocyanin dyes. The anthocyanin pigments contained identified by liquid chromatography are: cyanidine-3-sambubioside, cyanidine-3-glucoside, cyanidine-3-sambubioside-5-glucoside, and cyanidine-3,5-diglucoside The total content of anthocyanins in the concentrate was determined to be equivalent to cyanidine-3-glucoside at 2.8 gl-1 and in the lyophilisate 2.5 gl-1.
22

Antioxidační vlastnosti květů Sambucus nigra. II / Antioxidant properties of Sambucus nigra flowers. II

Kozoňová, Pavlína January 2016 (has links)
Drug Sambuci nigrae flos - Sambuci nigrae flos is obtained from the wild plants. The drug is primarily used to help reduce the symptoms of colds and flu. Elder flower provides antioxidant, anti-inflammatory, anticancer and diuretic effects. The main substances are flavonoids and hydroxycinnamic acid. Elderflowers from bred cultivars are not used to obtain drug so far. The aim of this work was to determine antioxidant acitivitiy of extracts of eldeflower cultivars. Cultivars ′Albida′, ′Allesö′, ′Aurea′, ′Bohatka′, ′Dana′, ′Haschberg′, ′Heidegg 13′, ′Juicy′, ′Korsør′, ′Mammut′, ′Pregarten′, ′Riese aus Voßloch′, ′Sambo′, ′Sambu′, ′Samdal′, ′Sampo′, ′Samyl′, ′Tulbing′ and ′Weinhenstephan′ were analyzed. Antioxidant activity was measured spectrophotometrically using DPPH ((2,2-diphenyl-1-picrylhydrazyl) radical method. Results of antioxidant activity were expressed as IC50 (concentration required for 50% reduction of the DPPH radical). The measured values are in the range 0.0419 - 0.0772 mg/ml. Cultivars 'Heidegg 13', 'Albida', 'Tulbing' showed the highest antioxidant activity, whereas the lowest activity was found in 'Pregarten','Korsør' and 'Allesö' clutivars.
23

Experimental study on the utilisation of substitute food resources by parasitic wasps and syrphid flies attacking the rosy apple aphid Dysaphis plantaginea (Passerini) (Homoptera :Aphididae)

Bribosia, Emmanuel J. 22 December 2004 (has links)
The rosy apple aphid Dysaphis plantaginea (Passerini) (Homoptera: Aphididae) is the most serious pest apple aphid in view of the scale of damages inflicted to the fruits by a small number of individuals. Although numerous natural enemies have been associated with D. plantaginea, they are unable to halt infestations soon enough in most commercial apple orchards obliging fruit growers to control it chemically to prevent severe economic losses. In order to reinforce the contribution of indigenous aphidophaga in regulating rosy apple aphids, the use of insectary plants selected to support two groups of specialist aphid antagonists, notably aphid parasitoids and aphidophagous monovoltine syrphids, was investigated. 1. A first step consisted in selecting appropriate plant species. The rowan tree Sorbus aucuparia L. and the common elder Sambucus nigra L. were selected for their ability to support substitute aphids for the rosy apple aphid parasitoid E. persicae Froggatt (Hymenoptera: Braconidae, Aphidiinae) and monovotine syrphids (Diptera: Syrphidae) respectively. 2. Next, trials were conducted to induce substitute aphid infestations on their host plants by introducing eggs of Dysaphis sorbi Kaltenbach on rowan and small colonies of Aphis sambuci L. on elder. The resulting aphid populations which developed on their respective host plants in spring proved to be exploited by the natural enemies expected, i.e. E. persicae and monovoltine syrphids of the genus Epistrophe. Besides, diapause mummies of E. persicae and diapausing last-instar Epistrophe larvac were recorded on rowan and in the elder litter respectively, indicating the successful settlement of the antagonists in the orchard environment. A complementary investigation devoted to syrphid adults indicated that females of all species recorded ovipositing on the eider shrubs, including Epistrophe spp. had consumed a large majority of apple pollen grains as a protein source required for egg maturation. 3. To comfort our choice in the two groups of aphidophaga considered, a study dedicated to their respective phenology versus the one of D. plantaginea showed that they could both potentially halt rosy apple aphid infestations by attacking the aphids while the latter still occupied the primary, fundatrix-induced rosette leaf colonies, i.e. a critical moment in rosy apple aphid control. 4. Finally, marking methods were tested to label E. persicae internally and the egg load of gravid syrphids. These trials were intended to pave the way towards future mark-release-recapture experiments aimed to evaluate the antagonists’ activity range and thus strategically position the insectary plants for optimal aphid biological control in the whole orchard. The first step of new approach in the biological control of D. plantaginea has been set with this study. Its originality lies in the induction of economically indifferent aphid infestations on selected plants introduced in the orchard to encourage well-targeted groups of specialist aphid antagonists. Further trials are still needed to validate the field efficacy of the insectary plant systems developed and evaluate their possible integration within the whole array of pest management tools in both organic and integrated apple production. / Doctorat en sciences, Spécialisation biologie animale / info:eu-repo/semantics/nonPublished
24

Improvement of Naturally Derived Food Colorant Performance with Efficient Pyranoanthocyanin Formation from Sambucus nigra Anthocyanins using Caffeic Acid and Heat

Straathof, Nicole January 2020 (has links)
No description available.
25

Hemijski sastav, biološke i funkcionalne karakteristike novih proizvoda od zove / Chemical composition, biological and functional characteristics of new elderberry products

Vujanović Milena 14 December 2020 (has links)
<p>Glavni cilj ove doktorske disertacije je određivanje hemijskog sastava, biolo&scaron;kih i funkcionalnih karakteristika novih proizvoda od zove. Dobijanje proizvoda na bazi zove zasniva se na primeni tradicionalnih i savremenih tehnolo&scaron;kih procesa proizvodnje. Iskori&scaron;ćenje prirodnog potencijala zove započeto je primenom tradicionalne i savremene (liofilizacija) tehnike su&scaron;enja. U cilju dobijanja visoko-vrednih ekstrakata ploda i cveta zove primenjene su tradicionalna (maceracija) i savremene (ultrazvučna i mikrotalasna) ekstrakcione tehnike sa dva ekstragensa (50% etanol i voda). Dobijanje matičnog soka od plodova zove podrazumevalo je primenu tradicionalnog načina ceđenja, dok je vino od plodova zove dobijeno po standardnom postupku proizvodnje vina. Vino je izloženo različitim temperaturnim tretmanima u različitom vremenskom periodu (60 &deg;C u toku 5 minuta, 60 &deg;C u toku 10 minuta, 70 &deg;C u toku 5 minuta i bez toplotnog tretmana) u cilju evaluacije biolo&scaron;ke aktivnosti dobijenog proizvoda. Etarsko ulje ploda i cveta zove je dobijeno hidrodestilacijom. Ispitivanje efikasnosti primenjenih tehnolo&scaron;kih postupaka su&scaron;enja i ekstrakcije je zasnovano na određivanju biolo&scaron;kih i funkcionalnih karakteristika dobijenih ekstrakata ploda i cveta zove. U ispitivanim ekstraktima ploda i cveta zove dominantne fenolne kiseline su hlorogenska i protokatehinska kiselina, a rutin i kvercetin-3-O-heksozid su dominantna flavonoidna jedinjenja. Biolo&scaron;ke i funkcionalne karakteristike su ispitane primenom različitih in vitro antioksidativnih, neuroprotektivnih, antitirozinaznih i antidijabetogenih testova. Primenom liofilizacije kao savremene tehnike su&scaron;enja i mikrotalasne ekstrakcije kao savremene ekstrakcione tehnike povećava se biopotencijal ispitivanih ekstrakata. Matični sok od plodova zove kao potencijalno novi funkcionalni proizvod je analiziran u cilju definisanja hemijskog, fitohemijskog i nutritivnog sastava, biolo&scaron;kog potencijala i senzorskih karakteristika. Ispitivanja dobijenog vina su bila usmerena na utvrđivanje optimalnih uslova za proizvodnju voćnog vina. Definisanjem hemijskog i fitohemijskog sastava i evaluacijom biopotencijala vina određen je optimalan temperaturni profil za dobijanje jednog od novih funkcionalnih proizvoda. Na osnovu utvrđenog hemijskog sastava etarsko ulje ploda i cveta zove se pokazalo kao potencijalno novi prirodni agens za održavanje svežine i produženja roka trajanja prehrambenih proizvoda. Zova je nesumnjivo samonikla biljna vrsta koja u budućnosti osnovano može biti polazna sirovina za kreiranje i dobijanje novih prehrmabenih proizvoda na domaćem i inostranom trži&scaron;tu.</p> / <p>The main goal of this doctoral dissertation is to determine the chemical composition, biological and functional characteristics of new elderberry products. Elderberry products were obtained via traditional and modern technological processes. The exploitation of the natural potential of the elderberry started with the application of traditional and modern (lyophilization) drying techniques. To obtain high-value extracts of fruits and flowers, traditional (maceration) and modern (ultrasonic and microwave) extraction techniques with two solvents (50% ethanol and water) were applied. Obtaining the juice from the elderberry fruits implied the application of the traditional cold pressing method, whereas wine from the elderberry fruits was obtained in accordance with the standard procedure of wine production. The wine was exposed to different temperature treatments in different periods (60&deg;C for 5 minutes, 60&deg;C for 10 minutes, 70&deg;C for 5 minutes and without heat treatment) to evaluate the biological activity of the product. The essential oil of the fruit and flower was obtained by hydrodistillation. The examination of the efficiency of the applied technological procedures of drying and extraction is based on observing the biological and functional characteristics of the obtained extracts of the said fruits and flowers. In the examined fruit and flower extracts, the dominant phenolic acids are chlorogenic and protocatechuic acid, while rutin and quercetin-3-O-hexoside are the dominant flavonoid compounds. Biological and functional characteristics were examined using various in vitro antioxidant, neuroprotective, antityrosinase, and antidiabetic tests. The application of lyophilization and microwave extraction (as modern drying and extraction techniques) increased the biopotential of the analyzed extracts. Elderberry juice, a potentially new functional product, was analyzed to define the chemical, phytochemical and nutritional composition, biological potential, and sensory characteristics. The wine was tested in order to determine the optimal conditions for the production of fruit wine. By defining the chemical and phytochemical composition and evaluating the biopotential of wine, the optimal temperature profile for obtaining one of the new functional products was determined. Based on the obtained chemical composition, it is determined that the essential oil of fruits and flowers is a potentially new natural agent for maintaining freshness and extending the shelf life of food products. Without a doubt, elderberry is a wild plant species that could be used in the future as the starting material for creating and obtaining new food products on the domestic and foreign markets.</p>

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