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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.
1

Možnosti využití výlisků z bezinek / The possibility of using of elderberry fruit pomace

Ondrušová, Pavlína January 2018 (has links)
This diploma thesis concerns the determination of anthocyanin pigments in the elderberry pomace (Sambucus nigra L). The theoretical part describes in general the plant specification, its chemical composition, botanical characteristics and the possibility of utilization of elderberry in food processing industry and in pharmacy. However, the main concern of this thesis are the anthocyanins. This part is closely focused on chemical structure and factors that have significant influence over their stability. There are briefly summarized the positive effects of these colourants and their use in the food industry. In the experimental part, the elderberry juice and the extracts from the rhizomes were prepared. Two different solvents, a 1: 1 water / ethanol mixture and a mixture of water and methanol in the same ratio were used as extractors. To identify and quantify the dyes in the prepared samples, a chromatographic separation system (HPLC) with a Kinetex EVO C18 column and isocratic elution of the combined mobile phases of water of acetonitrile and formic acid was developed. The analysis only took 12 minutes. Two major dyes cyanidin-3-glucoside and cyanidin-3-sambubioside were identified and quantified by HPLC. The largest amount of anthocyanins was obtained by extracting mixture methanol / water (594.6 ± 0.42 mg.100 g-1). The content of anthocyanin dyes in dry extracts and juice was also determined by the often-used pH-differential method. Both results were compared. The HPLC method provided very accurate results against the less demanding pH-differential assay method, which proved to be suitable for the indicative measurement of anthocyanin content in real samples.
2

Mikroskopická charakteristika květů z kulturních odrůd Sambucus nigra L. / Microscopic characterization of flowers from culivars of Sambucus nigra L.

Andělová, Veronika January 2015 (has links)
Sambucus Nigra belongs to the most favourite plants of our national folk medicine. It has important place in pharmacy and food industry. It is know in our environment mainly in wild form however increasing interest and demand for qualitative balanced drug contributed to cultivation of cultural varieties in plantations. Flower of Sambucus Nigra contains mostly flavonoids. For receiving of the most quality drug is necessary to follow the rules of harvesting and drying. Currently is drug obtained only just from the plants in wild nature. The goal of thesis was valorising of all characteristic features of flowers Sambacus Nigra and differentiation between cultural varieties and wild forms with using microscopic test of identity stated in Czech Pharmacopoeia 2009. Characteristic flower features of Albida, Alleső, Aurea, Bohatka, Dana, Haschberg, Juicy, Kőrsőr, Madona, Pregarten, Riese aus Vobloch, Tulbing and wild form of Sambuca Nigra were examined. All samples were brightened in solution of chloral hydrate and afterwards microscopic preparations were created. Results were photographically documented. Among the observed features belongs: cells containing sand of calcium oxalate, stomata and epidermal cells of crown leaf. Besides were observed pollen grains, flowers venation or cuticle corrugation of...
3

Stanovení rutinu v plodech bezu černého / Assessment of rutin in elderberries

Kaňová, Kateřina January 2013 (has links)
This work is focused on determination of the concentration of rutin in the fruits of elderberry (Sambucus nigra L.). The theoretical part provides an overview of the properties, occurrence and use of elderberry in natural healing, medicine and food industry. Furthermore, important substances contained in elderberry, especially flavonoids, including rutin, are mentioned. Properties, biological effects and the possibility of determination of rutin are briefly described. In the experimental part the optimization and validation of the method of high performance liquid chromatography (HPLC), which is used for identification and quantification of rutin in fruits of 18 elderberry species, was performed. The pressurized hot water extraction was used for the preparation and solid phase extraction (SPE) for purification of the sample. The largest amount of rutin was found in a variety of elderberry Albida, 6,70 mg per 1 g of dry matter. High concentrations of rutin included varieties Haschberg, Sambu, Pregarten, Sambo and Sampo. On the other hand, the lowest concentration was found in variety Aurea, 1,24 mg.g-1. Finally, rutin content in elderberries was compared with the content of rutin in elder leaves and branches andwith significant sources of rutin – buckwheat and rue.
4

The health of blue elderberry (Sambucus mexicana) and colonization by the Valley elderberry longhorn beetle (Desmocerus californicus dimorphus) in restored riparian habitat

Gilbart, Meghan. January 2009 (has links)
Thesis (M.S.)--California State University, Chico. / Includes abstract. "Located in the Chico Digital Repository." Includes bibliographical references (p. 67-73).
5

Stanovení kovů v ovocných šťávách / Determination of selected metals in fruit squashs

Drobilová, Marcela January 2011 (has links)
The theoretical part of the thesis deals with the technology of fruit juices production and characteristics of the known varieties of elderberry. There are also summarized available information on the presence and properties of minerals in food. In the practical part of the thesis 17 different varieties of elderberry juice and commercially available juice sold as food supplements were analyzed using ICP-MS technique. The concentrations of 15 selected essential and toxic elements were determined in these juices.
6

Flavonoidy v květech vybraných kultivarů Sambucus nigra L. / Flavonoids in some cultivars of Sambucus nigra L. flowers.

Krulišová, Markéta January 2016 (has links)
The aim of this work was to find out the content of flavonoids in the flowers of eleven cultivars of black elder (Sambucus nigra L.) and determine if their contents differ according to the statistical significance. Preparing the list of effects and substances that are contained in the flowers was the goal as well. The drug Sambuci nigrae flos is mostly used for its content of flavonoids and hydroxycinnamic acids in the therapy of colds and diseases of the urinary and respiratory tract. Its benefits were confirmed also by studies testing antibacterial and antiviral activity, diabetes and obesity, effects on the immune system and also protection against UV radiance. The content of flavonoids was established by the spectrophotometric method that is listed in the Czech Pharmacopoeia 2009 in the article Sambuci nigrae flos as the method for the determination of content. The statistic evaluation of the differences in the flavonoids content between the cultivars was made by ANOVA and the Bonferroni test. The demand of Czech Pharmacopoeia 2009 on the minimal content of flavonoids is 0,80%. This requirement was fulfilled in the flowers of these cultivars: Albida, Heidegg 13, Riese auß Voßloch, Sambu, Samdal, Sampo and Samyl. On the opposite side, flowers of the cultivars Allesö, Aurea, Dana and Juicy did...
7

A model of the longterm persistence of the valley elderberry longhorn beetle /

Greenberg, Aaron. January 1900 (has links)
Thesis (M.S.)--Humboldt State University, 2010. / Includes bibliographical references (leaves 59-60). Also available via Humboldt Digital Scholar.
8

Stanovení anthokyanových barviv ve vybraných druzích ovoce / Determination of anthocyanins in selected kind of fruit

Forejtarová, Darina January 2010 (has links)
Contents of this diploma thesis was introduction of method determination of anthocyanin pigments by liquid chromatography. Anthocyanin pigments was determined in various cultivars of elderberry (Sambucus nigra L.) and in selected samples of red wine. In the first part of the theory is described elderberry, its species and chemical composition. Some possibilities of processing and utilization of elderberry in medicine are mentioned here too. The next part of the theory is aimed at chemical agents in wine, characteristics of anthocyanins and their utilization in food processing industry. The methods for determination of anthocyanin pigments with focus on HPLC are also mentioned there. The main objective of the experimental part of this thesis was comparison of content of anthocyanins in various cultivars of elderberry and in selected samples of red wine. In samples of red wine was observed not only cultivars´ influence, but also influence of the crop year on the content of anthocyanin pigments. The separation of the anthocyanin pigments by high-performance liquid chromatography with diode array detection (HPLC/DAD) was performed. The highest content of anthocyanin pigments in elderberry was determined in the cultivar Haschberg. In the case of red wine, the richest source of anthocyanins was the cultivar André 2009 – Rakvice. Higher content of anthocyanins was explicitly proved in young wines rather than in older wines.
9

Obsah rutinu ve vybraných odrůdách bezu černého / Content of rutin in selected elderberry cultivars

Píšťková, Magdalena January 2011 (has links)
The aim of this diploma thesis was to determine the rutin content in springs and leaves of 19 elderberry species (Sambucus nigra L.) with use of liquid chromatography. Furthermore the rutin content was determined in its significant sources – rue and buckwheat. The observed values were compared in order to answer the question whether it is useful to use the elderberry spring and leaves as a new source of rutin. Theoretical part of the thesis describes elderberry in general, its chemical composition and its usage in medicine. Following part concentrates on important substances contained in elderberry – flavonoids. Also principles of extraction techniques and HPLC are discussed. In practice the rutin was gained from plant matrix with use of pressurized hot water extraction (PHWE) which was performed in three five minutes long cycles. Conditions during the PHWE were set up to 80 °C and 150 bars. Obtained extract was purified with use of SPE columns and analyzed by HPLC with DAD detector (wave length – 360 nm). HPLC was performed with SUPELCOSILTMLC-8DB column. The mobile phase was composed of MeOH, H2O, and HCOOH in ration of 36:61,5:2,5. The set up flow of mobile phase was 1 ml/min. In the leaves the highest rutin content was determined in Pregarten – 26,34 ± 0,50 mg/g. On the other hand the lowest rutin content in leaves was determined in Körsör – 3,74 ± 0,13 mg/g. In springs the obtained results were as follow. The highest content was determined in Samyl – 4,87 ± 0,01 mg/g and the lowest content was determined in Heidegg 13 springs – 0,56 ± 0,01 mg/g. Also the HPLC detection limit – 6,3 . 10-5 mg/ml and quantitation limit – 2,1 . 10-4 mg/ml were determined for rutin.
10

Charakterizace plodů bezu černého / Characterisation of elderberry fruits

Christovová, Silvia January 2014 (has links)
This master's thesis deals with the characterization of elderberry fruit (Sambucus nigra L.) with emphasis on the aroma active compounds (AAC) and vitamin C (ascorbic acid (AA), dehydroascorbic acid (DHA)). The theoretical part gives a brief outlook on the chemical composition and attributes of Sambucus berries, its healing properties and the means of processing. The rest of the theoretical part thoroughly examines the AAC and vitamin C. The suitable assessment methods are also discussed. The experimental part of the work consists of two main tasks. The first one was to assess the aroma profile of Sambucus berries using the HS-SPME-GC-FID. 18 samples were examined (the wild elderberry and 17 cultivated varieties). In total, 24 different volatile aroma active compounds were identified and quantified, 12 of which belonged to alcohols, 5 to aldehydes, 4 to esters, 1 to acids and 2 “other” compounds (linalool and -damascenone). The chemical composition of the individual samples was not uniform; no single sample contained all of the identified compounds. The second task was to assess the total vitamin C content (the sum of DHA and AA) using the HPLC. For the purpose of reducing DHA to AA three reducing agents were examined (DTT, TCEP and L-cysteine) at two different pH levels (7 and 4). TCEP at pH 4 turned out to be most efficient and was subsequently applied on the samples of 5 selected elderberry varieties. The measured vitamin C content was within the range of 5,1 – 13,0 mg per 100 g of fruit.

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