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Stevia rebaudiana - food and pharmaceutical industry applications
Rücker, Matěj ; Drastík, Martin (advisor) ; Kuchařová, Monika (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Candidate: Matěj Rücker Supervisor: Ing. Martin Drastík, Ph.D. Title: Stevia rebaudiana - food and pharmaceutical industry applications The first part of this thesis deals with the description of the plant and its substances, the most important are steviolglycosides, especially stevioside and rebaudioside A. In the following chapter, the toxicity and safety are evaluated, which is directly related to the use of stevia and steviolglycosides in food and pharmaceutical practice. In the next part, the utilization in the food industry and connected legislation is described. The harmfulness of the refined sugar is outlined as well. Application in the pharmacy is not so widespread, therefore this chapter deals primarily with the effects of steviolglycosides. Stevia rebaudiana Bertoni and steviolglycosides have great potential to replace sugar and other sweeteners. Due to their beneficial effects, they are very popular among researchers, so we can look forward to their widespread application in food and pharmaceutical industry in the near future. Key words: steviolglycosides, stevioside, rebaudiosede A, sugar, pharmaceutical industry, food industry
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SPE in steviol glycosides analysis
Dalecká, Karolína ; Drastík, Martin (advisor) ; Kubíček, Vladimír (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Candidate: Karolína Dalecká Supervisor: Ing. Martin Drastík, Ph.D. Title: SPE in steviol glycosides analysis In the first part of this diploma thesis, the solid phase extraction method is described. The topics like the workflow, usability of sorbents and their formats and interactions with analytes are covered. The second part of this thesis is focused on utilization of solid phase extraction on samples containing steviol glycosides. An overview of solid phase sorbents their forms; solvents used for extraction and elution of steviol glycosides is provided in the discussion section at the very end of this work. Taking into account the fact that stevia has been used more and more on the European market in recent years, and is found in more food and other products, the frequency of determination of steviol glycosides and the use of solid phase extraction is on rise. The most commonly extracted samples include food products with steviol glycosides used as sweeteners or extracts of dried stevia leaves. The main sorbents used for solid phase extraction include silica gel with octadecyl and divinylbenzene-co-vinylpyrrolidine copolymer. This type of extraction is most often connected with high...
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Determination of steviol glycosides by HPLC
Hollá, Marcela ; Drastík, Martin (advisor) ; Kubíček, Vladimír (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Candidate: Marcela Hollá Supervisor: Ing. Martin Drastík, Ph.D. Title of Diploma Thesis: Determination of steviol glycosides by HPLC A new HPLC method was developed and validated for simultaneous detemination of major steviol glycosides stevioside and rebaudioside A in food supplements. Separation took place in hydrophilic interaction chromatography mode on column with core-shell particles. The method was aplicated on analysis of steviol glycosides in products Valosun, SlaDIA, Solia and extract from dried stevia leaves. Isocratic separation was performed using Kinetex 2,6u HILIC 100A, (100 x 2,1 mm; 2,6 µm), Phenomenex analytical column with mobile phase consisted of acetonitrile/0,05 M ammonium formate adjusted with formic acid to pH=3 in ratio 90:10, with flow rate 0,7 ml/min, column temperature set at 30 řC, pressure 19,8 MPa, UV detection at 203 nm and injection volume 1 µl. We compared the results of the analyzes with content of stevioside glycosides declared by the manufacturer. The new developed method allows rapid analysis of food supplements and plant extract containig steviol glycosides. Key words: steviol glycosides, stevioside, rebaudioside A, Stevia rebaudiana Bertoni, high...
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