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Optimization of methods for the analysis of pharmaceuticals residues in different crops
Súkeníková, Kamila ; Zlámalová Gargošová, Helena (referee) ; Mravcová, Ludmila (advisor)
Aim of this thesis is to optimize the extraction method for extracting pharmaceuticals from various types of matrices. Presence of pharmaceuticals in the environment represent an increasing problem, even though they are only found in low concentrations. Therefore, great emphasis is placed on their analysis. Since the concentration of pharmaceuticals is often low and their chemical diversity is large, their analysis presents a significant challenge. For this reason, this thesis is focused on optimizing the extraction method from plant matrices. This optimization is carried out in order to obtain the best possible extraction method, and thus ensuring the highest possible yield of pharmaceuticals from radish, carrot, and mustard matrices. The optimization of the extraction method involved finding the parameters for individual steps of the QuEChERS extraction method that showed the best average yield for all pharmaceuticals.
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Determination of Natural Compounds in Select Plant Materials and Less Obvious Kinds of Fruit
Hohnová, Barbora ; Márová, Ivana (referee) ; Ventura, Karel (referee) ; Omelková, Jiřina (advisor)
Flavonoids are natural compounds widely distributed in plant kingdom. They are inseparable from human diet because they showed a protective effect against cancer, stroke and coronary heart diseases related to their antioxidant properties. Therefore, rapid and efficient extraction procedure prior to chromatographic analysis is required. The liquid extraction at elevated temperature and pressure – Pressurized fluid extraction (PFE) and Pressurized hot water extraction (PHWE), present fast, effective and environmentally friendly extraction methods for the determination of flavonoids in plant materials. PFE and PHWE followed by reversed phase high-performance liquid chromatography with UV-visible detection have been utilized for the determination of a group of flavonoids (rutin, myricetin, quercetin, luteolin, apigenin and kaempferol) in the leaves and berries of less common plants. The matrices were extracted by methanol, ethanol and water at higher temperature 40-120 oC and pressure 15 MPa during 15 minutes. The obtained results were compared with conventional Soxhlet extraction and ultrasound-assisted extraction, the same solvents were used. The most effective extraction of selected flavonoids was achieved by PHWE. PFE showed the extraction yields comparable to those of the Soxhlet extraction, and the lowest extraction power was displayed by ultrasound-assisted extraction.
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Determination of Natural Compounds in Select Plant Materials and Less Obvious Kinds of Fruit
Hohnová, Barbora ; Márová, Ivana (referee) ; Ventura, Karel (referee) ; Omelková, Jiřina (advisor)
Flavonoids are natural compounds widely distributed in plant kingdom. They are inseparable from human diet because they showed a protective effect against cancer, stroke and coronary heart diseases related to their antioxidant properties. Therefore, rapid and efficient extraction procedure prior to chromatographic analysis is required. The liquid extraction at elevated temperature and pressure – Pressurized fluid extraction (PFE) and Pressurized hot water extraction (PHWE), present fast, effective and environmentally friendly extraction methods for the determination of flavonoids in plant materials. PFE and PHWE followed by reversed phase high-performance liquid chromatography with UV-visible detection have been utilized for the determination of a group of flavonoids (rutin, myricetin, quercetin, luteolin, apigenin and kaempferol) in the leaves and berries of less common plants. The matrices were extracted by methanol, ethanol and water at higher temperature 40-120 oC and pressure 15 MPa during 15 minutes. The obtained results were compared with conventional Soxhlet extraction and ultrasound-assisted extraction, the same solvents were used. The most effective extraction of selected flavonoids was achieved by PHWE. PFE showed the extraction yields comparable to those of the Soxhlet extraction, and the lowest extraction power was displayed by ultrasound-assisted extraction.
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