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Supercritical Fluid Extraction of Sesquiterpene Lactones from Laserpitium archangelica.
Sajfrtová, Marie ; Kraus, V. ; Wimmer, Z. ; Cerhová, Marie ; Vlk, M.
The aim of the work was to describe the SFE of two STLs, archangelolide and trilobolide, from seeds of Laserpitium archangelica (Apiaceae). The objectives consisted in: (a) optimizing, investigating the SFE condition (pressure, temperature and concentration ofmodifier in scCO2) effect on the yield and concentration of STLs in extract, (b) \nDetermination of the SFE kinetics of major components in the extracts and (c) comparing the SFE with pressurised liquid extraction (PLE) and Soxhlet extraction.\n\n\n
Fulltext: content.csg -  PDF
Plný tet: SKMBT_C22018100509461 - PDF
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Kinetics of Supercritical Fluid Extraction of Carotenoids from Microalgae and Plants.
Sovová, Helena
This contribution summarizes previous results of our analysis of data on the supercritical fluid extraction of carotenoids from microalgae, adds comparison of the mathematical model with newly available experimental data, and applies the model on CO2 extraction of carotenoids from different plants, where equivalent extraction mechanisms are supposed to be valid.
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Plný tet: SKMBT_C22018100509360 - PDF
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Supercritical Fluid Extraction: A Green Method for the Isolation of Valuable Substances from the Various Biological Matrices.
Topiař, Martin ; Sajfrtová, Marie ; Šolcová, Olga ; Hradecký, J. ; Hůrková, K. ; Hajšlová, J.
Supercritical fluid extraction (SFE) using carbon dioxide is a sophisticated technology suitable for isolation of un-polar, high value biological active substances from the various biological matrices. In this study, it was used for the extraction of Magnolia x pruhoniciana flowers and Japonochytrium marinum fungus. Results obtained from the SFE were compared with those from conventional extraction methods. A total number of 37 compounds were identified in the magnolia isolate, from which α-pinene (18 % of peak area), cymene (14 % of peak area), β-pinene (13 % of peak area) and humulene (6 % of peak area) were its main components. Yield of valuable free fatty acids DHA and EPA obtained by the SFE of Japonochytrium marinum was more than 1.5 times higher in comparison with organic liquid extraction using mixture of methanol and dichloromethane.
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Plný tet: SKMBT_22317120815262 - PDF
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Preparation of Nanostructured Titania Thin Films Using Supercritical Carbon Dioxide
Cerhová, Marie ; Sajfrtová, Marie ; Matějová, L. ; Dřínek, Vladislav ; Daniš, S. ; Jandová, Věra
Extrakce čistým a modifikovaným superkritickým oxidem uhličitým (SFE) a extrakce podkritickou vodou byla využita k získání krystalických a čistých nanostrukturních tenkých filmů TiO2 a současně k odstranění organických prekurzorů ze syntézy solu sol-gel metodou. Při SFE byl sledován vliv teploty a použitého modifikátoru (vody, metanolu, etanolu a acetonu) na čistotu a mikrostrukturu tenkých filmů TiO2. Byl testován i kombinovaný postup extrakce, kdy se střídaly kroky s CO2 modifikovaným vodou a s CO2 modifikovaným organickými rozpouštědly. Čistota a krystalinita tenkých filmů byla zjištěna pomocí Ramanovy spektroskopie. Fázová složení a velikosti krystalů anatasu, žádané krystalické struktury, byly vyhodnoceny rentgenovou difrakční analýzou (XRD).
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Plný tet: SKMBT_C22015111812130 - PDF
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Extraction of beta-Sitosterol from the Stinging Nettle Root with Supercritical CO2
Sajfrtová, Marie ; Bártlová, Milena ; Sovová, Helena
The stinging nettle root contains both polar and non-polar biologically active substances. beta-Sitosterol (BS), the most important component of its neutral lipids, is active in the root extracts used for various alternative medicine treatments, including the reduction of enlarged prostate. Dry roots contaning 0.28 g/kg BS were extracted with CO2 at pressure 12-60 MPa and temperature 40-80 C. Though the maximum yield of BS was only 89 %, its concentration in extract was increased by 13 % compared to the extraction with hexane. Changing vials where the CO2 extract was collected, fractions with double and higher BS concentration could be obtained. The fractionation was simulated using a mathematical kinetic model of multicomponent extraction.
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Plný tet: SKMBT_C22013110513041 - PDF
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Differences in CO2 Extraction of Vegetable Oils, Essential Oils, and Minor Components from Plants
Sovová, Helena
Significant progress in understanding the phenomena that control supercritical fluid extraction from plants was made in the last years and is reflected in the literature. Combination of chemical engineering approach and botanical knowledge has appeared to be fruitful for the choice of extraction model and even for the prediction of extraction kinetics. This contribution refers to the papers utilizing knowledge of plant microstructure and location of extracted substances together with extraction equilibrium and attempts to specify the differences among extraction kinetics of vegetable oils, essential oils, and other substances. The most abundant substances like vegetable oils in seeds can be regarded in first approximation as non-interacting with plant matrix, in contrast to the minor components whose equilibrium concentration in CO2 is affected by their adsorption on matrix and often also by co-extracted substances.
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Plný tet: SKMBT_C22012102414100 - PDF
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