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Study of compounds influencing the antimicrobial effect of honey
Staňková, Petra ; Solich, Petr (advisor) ; Sklenářová, Hana (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Petra Staňková Supervisor: Prof. RNDr. Petr Solich, CSc. Title of Diploma Thesis: Study of compounds influencing the antimicrobial effect of honey Honey has many beneficial effects, but nowadays the antibacterial effect is the most appreciate one. This activity is due to many factors - the low pH, a small amount of water, high osmolarity, the presence of hydrogen peroxide, methylglyoxal, bee-defensin 1 peptide and other substances. However, all the substances contributing to this effect still have not been found and therefore we do not know the exact mechanism of antibacterial activity. Clarification of this situation could help with solving the problem with antibiotic resistant bacteria. This work aimed to confirm the presumption that substances structurally close to gentamicine are in honey. Seven samples of honey from France and one with German origin were used for this research. It included monofloral honeys and mixed ones, whose nectar was collected from several plant species. The extraction by dichloromethane was performed to eliminate the sugar. After derivatization by fluorescamine these substances were initially separated on a column of high performance liquid chromatography...
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Chemiluminiscenční hodnocení celkové antioxidační kapacity potravin
Vlčková, Jitka ; Polášek, Miroslav (advisor) ; Solich, Petr (referee)
Diplomová práce 2014 Abstract_ENG Jitka Vlčková ABSTRACT An investigation presented was concern to measure and evaluate the total antioxidant capacity (TAC) in samples of red wine clarified with four fining agents (polyvinylpolypyrrolidone and three different types of gelatin). All wine samples were treated by concentrations of 10, 20 and 40 g/hL of finings. The main aim was to discover how the particular agents in different dosages influence the TAC. The second part describes relations between changes in TAC in content of single antioxidant components (total polyphenols, anthocyanins, gallic acid and simple phenols). Total antioxidant capacity in red wine samples was evaluated using the Trolox equivalent antioxidant capacity assay (TEAC). A theoretical part of the thesis briefly summarizes basics about luminescence, focused on chemiluminescent reaction. Theory of free radicals and antioxidants, especially those included in red wine are also described. Process of winemaking aimed at fining is also contained in this part. An experimental part describes techniques of determination of the total antioxidant capacity, principle of chemiluminescent assay based on the luminol/peroxidase system. The results show the different behaviour of gelatin from the polyvinylpolypyrrolidone (PVPP). In general gelatin tends to...
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On-line SPE HPLC method optimization for determination of patulin mycotoxin in apple drinks
Holznerová, Anežka ; Šatínský, Dalibor (advisor) ; Solich, Petr (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Bc. Anežka Holznerová Supervisor: Doc. RNDr. Dalibor Šatínský, Ph.D. Title of Diploma Thesis: On-line SPE HPLC method optimization for determination of patulin mycotoxin in apple drinks The issue of food contamination with mycotoxins is a serious problem worldwide. These substances are highly toxic to humans and chronic effects on the human organism in very low doses may cause long-term medical complications. In our work we focused on one of the most common dietary mycotoxins - patulin, which is found in apples and related products (especially apple juices). High performance liquid chromatography (HPLC) coupled with on- line solid phase extraction (SPE) using a column switching technique for sample treatment was developed for determination of mycotoxin patulin in apple drinks and juices. A volume of 250 µl of juice sample was injected directly into the on-line SPE-HPLC system. After injection of the sample the extraction of patulin from juice matrix was carried out on SPE precolumn. SPE precolumn 25 x 3 mm was filled with Supel MIP Patulin sorbent, which is a specific "molecularly imprinted polymer" (MIP) designated for the selective extraction of patulin from an apple matrix. As the...
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Stanovení acetylcholinu pomocí LC-MS ve vzorcích mozkových mikrodialyzátů LC-MS/MS
Vrobel, Ivo ; Solich, Petr (advisor) ; Kujovská Krčmová, Lenka (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Ivo Vrobel Supervisors: Prof. RNDr. Petr Solich, CSc; Department of Analytical Chemistry, Faculty of Pharmacy, Charles University in Prague Prof. Seppo Auriola, MSc.(Chem.) Marko Lehtonen; Department of Pharmaceutical Chemistry, School of Pharmacy, University of Eastern Finland in Kuopio Title of master's thesis: LC-MS/MS analysis of acetylcholine in brain microdialysis samples Novel fast and simple LC-MS/MS method of ACh quantification in brain microdialysis samples utilizing stable-isotope-labeled IS was developed. The chromatographic step is based on revered-phase mode of pentafluorophenylpropyl (PFPP) column. The satisfactory retention of ACh is achieved with highly aqueous mobile phase containing 0.05% of the ion-pairing agent TFA and 4% of ACN in 4 min analytical run. Ionization of ACh and IS with low background noise and tolerant towards use of TFA was performed with atmospheric pressure thermospray ionization (APTSI). The selectivity of ACh and IS detection was obtained by SRM modes of MS/MS in the linear ion trap mass analyzer. The performance of developed method was cross validated to the validated method used in the laboratory for ACh measurements. The set of microdialysis...
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Sequential Injection Analysis with Lab-on-valve Module (SIA-LOV) Technique in the Analysis of Biologically Active Substances
Pavlíček, Ondřej ; Polášek, Miroslav (advisor) ; Solich, Petr (referee) ; Bajgar, Jiří (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Department of analytical chemistry Candidate Mgr. Ondřej Pavlíček Supervisor Doc. RNDr. Miroslav Polášek, CSc. Title of Doctoral Thesis Sequential injection analysis with lab-on-valve module (SIA-LOV) technique in the analysis of biologically active substances. This dissertation is devoted to determination of biologically active substances by means of sequential injection analysis (SIA). The theoretical part gives a recent overview of scientific knowledge concerning non-separative flow methods, focusing especially on SIA with Lab-on-Valve (LOV) module. Regarding applications of the SIA, problems of on-line sample treatment using solid phase extraction columns and of SIA methods employing enzyme reactions including sample pre treatment automationare dealt with. Theoretical background of enzymology, especially enzyme-substrate, enzyme-inhibitor and enzyme- -inhibitor-reactivator interactions are discussed. Theory of cholinesterases is described in more detail, its role in human organism and its application as biomarker in enviromental analysis is emphasized. An overview of detection techniques for determination of cholinesterase activity is also given. The experimental part is split into two issues. The former one deals...
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Using of Separation Methods for Clinical Research
Drastíková, Markéta ; Solich, Petr (advisor) ; Malíř, František (referee) ; Štěrbová, Petra (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of analytical chemistry Candidate: Markéta Drastíková (maiden name Kašparová) Supervisor: Prof. RNDr. Petr Solich, CSc. Title of Doctoral Thesis: Using of separation methods for clinical research This doctoral thesis deals with development and validation of a chromatographic determination of liposoluble vitamins and with optimization of biological materials preparation. The first part of this work is focused on vitamins D, A and E assessment in serum. To separate studied analytes two different methods were developed successively. 1) Separation employing monolithic columns - two different monolithic columns Chromolith Performance RP-18e, 100×4.6 mm and SpeedRod RP-18e, 50×4.6 mm were connected in series. Vitamins 1,25(OH)2D3, 25(OH)D3, retinol, tocol (internal standard), cholecalciferol, ergocalciferol and α-tocopherol were separated within 6.5 minutes using step gradient elution. 2) Separation exploiting a core-shell column - Ascentis Express RP-Amide 75×3.0 mm. To decrease the separation time a linear gradient was employed. The determination of 25(OH)D2, 25(OH)D3, tocol (internal standard) α-tocopherol took 8.5 minutes within separation of impurities. Developed solid phase (SPE) and liquid-liquid extraction (LLE)...
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Vývoj nové pyruvát-selektivní elektrody pro kontrolu kvality vína
Zelená, Lucie ; Solich, Petr (advisor) ; Sklenářová, Hana (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Lucie Zelená Supervisors: Prof. Maria da Conceição Branco da Silva, Dr. Célia Maria Pinto Gomes Amorim; Department of Analytical chemistry, Faculty of Pharmacy, University of Porto. Prof. RNDr. Petr Solich, CSc; Department of Analytical Chemistry, Faculty of Pharmacy, Charles University in Prague. Title of master's thesis: Development of a new pyruvate-selective electrode for wine control Pyruvate and other organic acids can influence the properties of wines as for example flavor, color, aroma or stability. New fast, low-cost, simple and sensitive methods have been developed for wine quality control. A development of a new selective electrode for potentiometric determination of pyruvate in wine samples was the aim of this work. Sensors based on PVC membrane using 5,10,15,20-Tetraphenyl-21H,23H-porphine manganese (III) chloride as ionophore were under study. Several solvent mediators and lipophilic additives were tested in optimization of response characteristics of sensors. The most interesting response showed membrane with 2-Nitrophenyl phenyl ether as a solvent mediator and Potassium tetrakis(2-chlorophenyl)borate as a lipophilic additive. Sensors with the best characteristics are...
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Optimization of HPLC metod for the determination of polycyclic aromatic hydrocarbons in cephalopods
Cyrusová, Tereza ; Solich, Petr (advisor) ; Matysová, Ludmila (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Kralove Department of analytical chemistry Candidate: Bc. Tereza Cyrusová Consultant: Prof. RNDr. Petr Solich CSc., Prof. Angelina Pena, Ph.D. Diploma thesis title: Optimization of HPLC method for the determination of polycyclic aromatic hydrocarbons in cephalopods Polycyclic aromatic hydrocarbons (PAH) are compounds dangerous for both environment and human health. Monohydroxyderivatives of PAH are their very important derivatives that arise in the detoxification process of PAH in the body of human and other organisms. Some monohydroxyderivatives of PAH have been assessed as a marker of PAH exposure. The main goal of this work was to optimize the analytical method for determination of selected PAH monohydroxyderivatives (1-hydroxypyrene, 2-hydroxyfluorene, 1-hydroxynaphtalene, 1-hydroxyacenaphtene) in the bodies of cephalopods. The used method was high-performance liquid chromatography with fluorescence detection. The detection wavelengths and mobile phase composition were selected. A column study, verification of antioxidant application and degradation study were carried out. Subsequently the optimization of conditions for determination of all four substances simultaneously was done. Based on these steps, for the partial experiments ACE...
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