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Use of LC/MS technique to analysis of some physiologically active natural compounds
Trčková, Marie ; Čáslavský, Josef (referee) ; Kočí, Radka (advisor)
Presented work is focused on application of combined instrumental method RP-HPLC/ESI-MS in analysis of several groups of natural compounds with positive physiological activities. Especially some antioxidants were studied in commonly and abundantly consumed food. Moreover some other substances than standard compounds were observed in complex dies. In conclusion the HPLC/ESI-MS method is comparatively advantageous in phenolic analysis, while another type of ionisation would be used in case of carotenoid compound.
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Determination of tensides in waters by separation methods
Brestovská, Marta ; Řezáčová, Veronika (referee) ; Čáslavský, Josef (advisor)
Surfactants are synthetically made surface-active agents contained in washing and cleaning products. They decrease the surface tension and remove dirt. Surfactants can be divided into three basic classes: anionic, cationic and non-ionic. Thanks to the massive use they penetrate into waste water and can disturb the environment. This diploma thesis deals with the occurrence of surfactants in water and their determination by separation methods, especially LC / MS.
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The Use of Liquid Chromatography for Determination of Drug Residues
Dvořáková, Petra ; Hajšlová, Jana (referee) ; Chýlková, Jaromíra (referee) ; Sokol, Jozef (referee) ; Vávrová, Milada (advisor)
This work is based on the occurrence of drug residues in the environment. This study is focused on the development and optimization methods for determination of selected drugs in the surface water, aquatic sediment and sewage sludge from waste water treatment plant. From the group of drugs were chosen antibiotics. Antibiotics presented in the environment can cause adverse effects including toxic effects, immunity disorders and indirect bioalteration effects. Sulfonamide antibiotics, which are used in the treatment of urinary and respiratory tract infections as well as in the treatment of other infectious diseases, were chosen as a target compounds. Three optimized analytical methods for determination of sulfonamide antibiotics were developed. For the optimization of extraction were tested: solid phase extraction, pressurized solvent extraction, microwave extraction and ultrasonic extraction. For the final analysis was used liquid chromatography with two detectors - diode array detector and mass spectrometer. These optimized methods were applied for the analysis of real samples. The surface water and sediment samples were collected from two Moravian rivers (the Svratka river and the Svitava river). Samples of sewage sludge were collected from waste water treatment plant Brno-Modřice. Fish samples from the Svratka river were also collected. It was observed that all the selected sulfonamide antibiotics are present in real sediment samples (ug.kg-1). Simultaneously presence of some target analytes in real surface water (ug.l-1) and in sewage sludge (ug.kg-1) samples has been confirmed. In samples of surface water from the Svitava river and in fish samples sulfonamide antibiotics were not detected or their concentrations were below the limit of detection.
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Study of Exposure PBDE and Perfluorinated Compounds into Aquatic Ecosystem
Vondráčková, Ilona ; Chýlková, Jaromíra (referee) ; Hroch, Martin (referee) ; Kráčmar, Stanislav (referee) ; Vávrová, Milada (advisor)
In the presented PhD. thesis, problems covering occurrence of polybrominated diphenyl ethers (PBDE) and perfluorinated compounds in the environment were solved. The study was focused on identification and further verification of optimal methods in order to determine PBDEs and perfluorinated compounds sampled from the aquatic ecosystem. Polybrominated diphenyl ethers belong to persistent compounds classified as main pollutants; within the environmental constituents, they have been observed particularly in the last decade. For these studies, there were selected surface water matrices and sediments taken in various localities within the river Svratka basin. The analyses were to demonstrate whether they accumulate and remain in these specific matrices for longer time. There we assessed the congeners of polybrominated diphenyl ethers as follows: BDE-28, 47, 66, 85, 99, 100, 153, 154 and 183. In order to isolate them from matrices, various extraction techniques were used, i.e., ultrasonic extraction, microwave extraction, and pressure solvent extraction. Gas chromatography method with electron capture detection (GC/ECD) was selected for determination. The accomplished studies also assessed basic chemical, physical and environmental characteristics of diphenyl ethers in the environmental constituents. The attention was also paid to perfluorooctanoic compounds (PFOA), (PFOS) and (FOSA); physico-chemical properties of these organic pollutants were characterised and their toxicological and environmental aspects were evaluated. Usability of extraction techniques (ultrasonic extraction, pressure solvent extraction, solid phase extraction) applied to PFCs isolation from sediments samples was assessed. Identification and quantification of these analytes were performed using a high performance liquid chromatography/mass spectrometry method (HPLC/MS). After that, the optimized methods applied to real samples. Surface water and sediments were sampled within the river Svratka basin, in particular, from 19 sampling localities. PBDE occurrence was confirmed in sediments samples from the Svratka river (g.kg-1), PBDE were not detected in the surface water samples, their concentrations were below the detection limit, resp.; perfluorinated compounds were not detected in sediments and water samples at all.
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Use of polarimetry and refractometry for determination of invert sugar concentration in invert syrups
Mrůzková, Karolína ; Šárka,, Evžen (referee) ; Hamtil,, Roman (advisor)
Invert syrup is a liquid sweetener, which is produced by sucrose hydrolysis to form fructose and glucose. Important qualitative parameter of invert syrup is the sucrose inversion – weight percentage of invert sugar (sum of fructose and glucose) in invert syrup dry mass. This diploma thesis presents a possibility of sucrose inversion determination by polarimetry in combination with refractometry in invert syrups of 70–78 % dry mass produced at 80 °C and pH 2,4. New relationship describing the sucrose inversion as a function of polarization and refractometric dry mass was determined. The results of sucrose inversion determined using this new relationship were compared to results obtained by HPLC/RI, which was used as a reference method. The difference between these 2 determination methods was 0,1 ± 0,5 %. The new relationship was detemined with reference to the fact, that under the processing conditions, more glucose than fructose is formed. The fructose : glucose concentration ratio formed under processing conditions was observed to be equal 0,96 ± 0,02.
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Monitoring of sulfonamides in wastewater from sewage treatment plants with different treatment technologies
Chaloupková, Petra ; Dvořáková, Petra (referee) ; Vávrová, Milada (advisor)
The aim of this thesis is to determine the presence of pharmaceuticals in wastewater from several wastewater treatment plants (WWTPs) with different number of equivalent persons and different treatment technologies. Five sulfonamides were chosen for a determination due to their wide usage in human and veterinary medicine practice. The specific compounds are sulfamerazine, sulfamethazine, sulfapyridine, sulfathiazole a sulfamethoxazole. For the determination of those sulfonamides, an UHPLC/DAD analytical method was chosen and optimized. There was also a need for optimization of SPE extraction method, especially a sample volume optimization. 250 mL was chosen as an ideal volume of wastewater sample for SPE. The optimized method was used for determination of sulfonamides in real wastewater samples from WWTP in Podivín, Pohořelice, Hustopeče, Valtice, Lednice and Mikulov. Average concentrations of pharmaceuticals in influent and effluent wastewater samples were in a range of 0,1 – 1 µg/l. The concentration of sulfonamides was mostly found higher in influent samples and lower in effluent samples. It can be said that a partial recovery of sulfonamides on WWTPs was observed.
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Probiotics and prebiotics and their co-encapsulation
Šnajdarová, Karolína ; Bokrová, Jitka (referee) ; Márová, Ivana (advisor)
This bachelor thesis is focused on study of probiotic cultures and options of coencapsulation with specific substrates called prebiotics. Lactobacillus acidophilus and Bifidobacterium breve were used as encapsulated microorganisms. As the specific substrates inulin, psyllium, apple fiber and hemp fiber were tested. Prebiotics was added to probiotics both in untreated form and in hydrolyzed form. The stability and viability of the cells have been studied by microscopy for the period of 6 weeks. Particles were stored in the enviroment of 2.5% citric acid. As the best substrate for cell growth the hemp fiber was found. The hemp fiber exhibited the highest increase of cells count. During observation of long-term stability in the model digestive conditions, particles with hemp fiber were destroyed in instestinal juices. For that reason, particles with hemp fiber could be used in food supplements with targeted transport. The bachalor thesis is also focused on characterisation of prebiotics components. The highest amount of total sugars in the group of non-hydrolyzed prebiotics exhibited psyllium. The highest content of reducing sugars both in the groups of non-hydrolyzed and hydrolyzed prebiotic had hemp fiber. By the method of thin-layer chromatography was found out that the main components of hydrolyzed prebiotics are glucose and fructose. Further, some disaccharides and oligosaccharides were obtained by TLC analysis. For characterisation of prebiotics by HPLC the column Rezex exhibited better sensitivity. HPLC analysis confirmed that the main components of prebiotics are glucose and fructose, some more complex carbohydrates were found too.
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Study of the medium influence on the pollutants sorption on microplastics
Hamplová, Marie ; Kučerík, Jiří (referee) ; Mravcová, Ludmila (advisor)
With the increasing production of plastic waste, the pollution of the environment by persistent microplastics is increasing simultaneously. Other environmental pollutants, such as various pharmaceuticals, can be sorbed on microplastics. This increases the toxicity of microplastics and their risk to living organisms. Nowadays, the use of so-called biodegradable polymers, which are supposed to degrade spontaneously, is expanding. However, their degradation can also produce microplastics. Therefore, this bachelor thesis deals with the sorption of drugs onto microplastics from biodegradable polyhydroxybutyrate (PHB) and with the influence of the surrounding aqueous environment on the rate and mechanism of sorption. Sorption of drugs onto microplastics made of synthetic polyethylene terephthalate (PET) was also carried out for comparison. The quantity of drugs was analysed by UPLC-ESI-TQ. Sorption was observed from the drug mixture for antibiotics tetracyclines. The pH value of the surrounding environment influenced the sorption rate of tetracyclines, the highest sorption occurred at acidic pH 4. According to the results of evaluation of sorption by Langmuir and Freundlich adsorption isotherms, PHB microplastics have a higher sorption capacity than PET microplastics. Therefore, PHB microplastics could be a risk for living organisms.
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Removal of sulfonamide antibiotics using advanced oxidation processes
Fučík, Jan ; Suková, Petra (referee) ; Tulková, Tereza (advisor)
This thesis deals with a present problem of increasing concentrations of pharmaceuticals and other micropollutants in aquatic environment, because these micropollutants are not treated sufficiently in conventional wastewater treatment plants. It is necessary to develop new technological processes, that are able to treat these pollutants sufficiently. One of the options is that conventional methods would be complementary with advanced oxidation processes (AOP), which would work as a tertiary cleaning process on wastewater treatment plants. The actual knowledge, principle of the plasma discharge and principle of analytical methods is described in theoretical part of the thesis. In experimental part of the thesis, the plasma discharge is used for removal of sulfonamide antibiotics (sulfamethoxazole), as the representative of AOP. Samples were taken during the plasma treatment of the model solution of sulfamethoxazole. These samples were analysed by LC-ESI-MS as the appropriate analytical method. An efficiency of degradation of sulfamethoxazole in different solutions (neutral, acidic and alkaline) was evaluated in this bachelor thesis. A suitability of plasma application on degradation of sulfonamide antibiotics was reviewed by comparing with other AOP.
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