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Removal of antibiotics from wastewater by advanced oxidation technologies
Macsek, Tomáš ; Rusník,, Igor (referee) ; Bodík,, Igor (referee) ; Hlavínek, Petr (advisor)
Antibiotics are substances that inhibit the growth of microorganisms and are widely used in modern medicine. High consumption of antibiotics correlates with their elevated occurence in sewage systems, from where they are further released into the environment. The threat of their occurrence in the environment is in triggering the formation and spread of antibiotic resistance. This thesis focuses on the removal of selected antibiotics and partly on the antibiotic resistance from wastewater by advanced oxidation processes (AOPs). AOPs are based on the creation of highly reactive hydroxyl radicals, which are able to oxidize even highly persistent substances. The thesis focuses on the purification of effluents from municipal wastewater treatment plants (WWTP), which are identified as the main source of pharmaceutical pollution in the environment, by AOPs mainly based on ozonation. These processes were tested under laboratory conditions on model water as well as under real conditions as the tertiary stage of the treatment at Brno-Modřice WWTP under various operating states. As the results of the performed experiments show, it could be concluded that the studied AOPs are capable of effective degradation of studied antibiotics from the treated medium. Under real conditions, the antibiotics sulfamethoxazole, trimethoprim, azithromycin and clarithromycin were monitored. Output concentrations in each operational state were achieved to be below the limit of detection for all four antibiotics. The application of AOPs based on ozonation as the tertiary step of the treatment also had a positive effect on the reduction of microbial contamination and antibiotic resistance. Within the pilot plant experiments, a reduction of up to 4 orders of magnitude of E.coli, coliform microorganisms and a reduction of their resistant strains in the range of 1.4 - 4.0 logs were observed, compared to the effluent from the WWTP.
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Use of the QuEChERS method for the analysis of fluoroquinolone antibiotics in soil
Brabcová, Kristýna ; Zlámalová Gargošová, Helena (referee) ; Mravcová, Ludmila (advisor)
The content of this master's thesis is an application of frequently used extraction method QuEChERS on soil or other samples like litter or manure containing fluoroquinolone antibiotics. In the theoretical part of this thesis are chapters describing drugs, antibiotics and antibiotic resistance. Fluoroquinolones are described in more details with their properties, appearance and behaviour in the environment. The last chapter is focused on analytical methods. In the experimental part of this thesis is chosen in accordance with available publications the most suitable extraction method. This method is tested and optimized on soil samples. The optimized method is applied on the real soil and poultry litter samples to determine the amount of ciprofloxacine and enrofloxacine. This extraction method is used on other fluoroquinolone antibiotics (norfloxacine, ofloxacine, pefloxacine, moxifloxacine) in soil. All of the samples were analyzed by LC-MS.
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Role of extracellular DNA in microbial biofilms
Gromov, Anton ; Chytilová, Aneta (referee) ; Obruča, Stanislav (advisor)
Abstract This bachelor’s thesis deals with defining the role of extracellular DNA in microbial biofilms. The thesis includes a part about the basic characteristics and functions of biofilms, as well as the characteristics and functions of extracellular DNA. The theoretic part additionally deals with the process of formation of biofilms, and the influence of different types of stresses on it. Also, the paper discusses the role of such stresses. The role of biofilm in bacteria and their reproduction methods are also discussed. An interesting section of the thesis outlines the impact of antibiotics on biofilms, or the ways to gain DNA or use DNase. The eDNA functions and their effects on bacterial defence will be discussed thoroughly. In the experimental part, the biofilm content was examined and compared with cells growing in a liquid and solid medium. Measurement of DNA content in media was carried out and the effects of salt and temperature stresses on biofilm were also measured. Stress conditions affected the production of PHB, which is used as a reserve form of energy and carbon. Total sugars were measured using an anthracite reagent to study the effects of stresses on the content of macromolecules. The presence of eDNA in biofilms and planktonic cells was firstly checked using gel electrophoresis and then accurate concentrations in planktonic and biofilm cells were determined using different spectrophotometric methods.
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Analysis of fluoroquinolone antibiotics in the soil
Vdolečková, Monika ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
The thesis dealt with the global problem of the occurrence of pharmaceuticals in the environment, specifically fluoroquinol antibiotics (ciprofloxacin and enrofloxacin), which are among other critically important antibiotics. These drugs enter the soil environment through the application of already contaminated animal waste (e.g. manure) or through wastewater used in irrigation or through the application of treated sewage sludge, which may contain drug residues. Increasing concentrations of these antimicrobial drugs in the environment provide an environment for the emergence and spread of microbial resistance. The accumulation of these drugs then leads to the emergence of resistance to these antibiotics. The experimental part of the thesis focused on the optimization of a method for the extraction and subsequent determination of fluoroquinolones in soil and litter. For this purpose, parameters related to the extraction yield of fluoroquinolones from the soil matrix were optimized, such as sample weighting, selection of a suitable extraction medium, SPE performance, elution method from the SPE, etc. Extraction recoveries of 70 to 140 % were achieved as part of the optimization. Finally, the optimised method for extraction of fluoroquinolones from poultry litter and soil samples provided by the ÚKZÚZ was used. The experimental results confirm the long-term persistence of these drugs in the environment.
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Study of selected antibiotics sorption on polyhydroxybutyrate
Amrichová, Anna ; Doležalová Weissmannová, Helena (referee) ; Řezáčová, Veronika (advisor)
The bachelor thesis deals with the issue of sorption of antibiotics on microplastics. Antibiotics and microplastics are now a highly studied topic, due to the positive and negative properties. Antibiotics with groups of sulfonamides and quinolones were selected for the experiment. From sulfonamides, sulfamethoxazole and trimethoprim were selected, and from the quinolones, enrofloxacin and ciprofloxacin, which have already been the impetus for some microplastic studies. Biodegradable polyhydroxybutyrate was used as the microplastic. Two experiments were performed in the laboratory. The first aimed to monitor the time dependence of antibiotic sorption on polyhydroxybutyrate, the second the concentration. The concentration dependence was subsequently evaluated using the Freundlich and Langmuir isotherms. The method of liquid chromatography with mass spectrometry was used for analyzes.
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Optical micromanipulation and Raman spectroscopy of cells in microfluidic systems
Klementová, Tereza ; Samek, Ota (referee) ; Mravec, Filip (advisor)
This diploma thesis deals with optimization of analysis process and measuring antibiotics induced changes in E. coli cells via Raman spectroscopy, LTRS and microfluidic systems. Optical micromanipulation by a laser beam allows noncontact and noninvasive manipulation of objects on scale 10^-5–10^-8 m, for example bacterial cells. Microfluidic device consists of microchannels and microchambers in transparent polymer and it is used for isolation, observation and cultivation of bacterial cells. Combination of these methods gives an effective tool for observation, manipulation and analysis of microorganisms. E. coli is a microorganism potentially pathogenic for humans and faster detection of its sensitivity to antibiotic treatment would make the whole process of diagnostics and treatment easier. We performed laser tweezer-Raman spectroscopy and conventional Raman spectroscopy of bacterial cells and cells under antibiotic stress and collected Raman spectra and characteristic areas were compared with literature to establish the reliability and usefulness of this method.
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Application of separation methods for the determination of selected pharmaceuticals in waters
Burešová, Jitka ; Opatřilová, Radka (referee) ; Vávrová, Milada (advisor)
Antibiotics are widely used pharmaceuticals in human and veterinary medicine. These compounds are biologically active. They decrease efficiency of biological processes in wastewater treatment plants. Antibiotics are not eliminated from sewage water completely and they are discharged as contaminants into the receiving waters. Several methods exist for the determination of antibiotics in sewage water. In the first place liquid chromatography, gas chromatography and capillary electrophoresis are used. The aim of this thesis was to developed a suitable izolation technique and an optimal analytical method for identification and determination of penicillins in wastewater. For determination was selected amoxicillin, ampicillin and benzylpenicillin (penicillin G). These are very often used penicillins. An optimized method was used for determination of these penicilins in real samples from a wastewater treatment plant situated in Veterinary and pharmaceutical university in Brno and from the large-scale wastewater treatment plant in Brno-Modřice. Real samples were concentrated using SPE (solid phase extraction). For penicillins determination were used high performance liquid chromatography with diode array detection (HPLC/DAD).
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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 the availability of antibiotics in soil
Hroncová, Michala ; Landová, Pavlína (referee) ; Řezáčová, Veronika (advisor)
The diploma thesis is focused on the determination of tetracyclines, sulfonamides and fluoroquinolones from soil. Antibiotics such as tetracycline, chlortetracycline, oxytetracycline. ciprofloxacin, trimethoprim, sulfamethaxazole and sulfadiazin were selected due to frequent use in veterinary medicine. Due to the fact that the soil is a complex matrix and contains many components that can interfere with the detection signal of analytes, it was necessary to use the MAX column in the SPE method, which removes fulvic aned humic acid from analytes and the HLB column Final analysis of the analytes was performed by liquid chromatography with mass detesction (LC-MS). The method was also used for real soil samples, which were delivered from ÚKZUS.
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Determination of antibiotics in the soil ecosystem
Brož, Tomáš ; Zlámalová Gargošová, Helena (referee) ; Mravcová, Ludmila (advisor)
This work deals with a current issue of increasing drug concentrations and thus the growing number of resistant bacteria in the soil. One of the problem helping this issue is the fertilization of agricultural fields with animal faeces, in which antibiotics occur in an unchanged and still active form, as well as the insufficient effectiveness of conventional methods used in wastewater treatment plants. In an effort to improve the monitoring of this problem, a method for the determination of these antibacterial agents in the soil matrix, using solid phase extraction, and also a UPLC/MS method for their evaluation have been developed and optimized. From the group of sulfonamide antibiotics, sulfacetamide, sulfadiazole, sulfamerazine, sulfamethazine, sulfamethoxazole, sulfapyridine, sulfasalazine, sulfathiaosal and trimethoprim were selected. The lowest limit of detection for the method is 0.3 µg/g for sulfathiazole and the highest of 8.1 µg/g for sulfasalazine. The highest average yields were achieved with sulfamethoxazole, namely 63 ±8 %.
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