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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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Enterobacter spp. resistant to beta-lactam antibiotics from urban and hospital wastewater
Kocúrová, Petra ; Masaříková,, Martina (referee) ; Sukkar,, Iva (advisor)
The increasing prevalence of antibiotic–resistant bacteria pose a huge risk for public health. Enterobacter spp. is a common in the environment but it is also documented as a frequent cause of human disease. Enterobacter spp. resistant to cephalosporins and carbapenems is increasingly detected globally both in and out of hospital setting. This thesis examines the occurrence of Enterobacter spp. strains resistant to –lactam antibiotics especially in wastewaters but also in treated water discharged into the environment. The aim of this study was to characterize a set of 205 strains of Enterobacter spp. selected on medium supplemented with cefotaxime and meropenem. The water samples were collected from three regional cities in the Czech Republic and originated from hospital wastewater, inflow and outflow of municipal wastewater treatment plant (WWTP), from a river above and below the WWTP. The isolates were screened for presence of eight genes encoding production of broad–spectrum –lactamases (ESBL; CTX-M, GES) and carbapenemases (GES, IMI/NMC-A, IMP, KPC, NDM, OXA-48, VIM) by the polymerase chain reaction (PCR) method. The phenotype of isolates carrying the gene of interest was tested for –lactamase production by the Mastdisc test and susceptibility to 24 different antibiotics by microdilution method. The phylogenetic relatedness was determined using restriction digestion in combination with pulsed-field gel electrophoresis (PFGE). From total of 205 strains, 36 isolates carried the gene of interest for –lactamase production. These isolates originated mostly from hospital wastewater (n=31) of all sampled sites (A, B and C). Also one isolate was detected in the WWTP influent in site B and four isolates came from the WWTP effluent in sites A and B. The following genes of interest were detected among the isolates: blaGES (n=16), blaCTX-M (n=24), blaOXA-48 (n=1) and blaNMC-A (n=1) a combination of two genes were detected in one isolate. All characterized isolates (n=36) showed a multidrug–resistant profile. High resistance to aminoglycosides was reported (76,9 %) with the exception of amikacin (19,4 %). In the case of carbapenems, resistance to ertapenem was observed (77,8 %), while a majority of strains were susceptible to meropenem, where resistance was detected only in 13,9 % of cases. Different resistance profile has been reported to cephalosporin antibiotics. All tested isolates showed resistance to antibiotics cefazolin and cefuroxime (100 %), lower rates of resistance were reported to antibiotics cefoperazone (80,6 %), cefotaxime (77,8 %) and cefepime (69,4 %). The lowest resistance in this group of antibiotics was found to cefoperazone/sulbactam (33,3 %). All selected isolates showed resistance to tetracycline antibiotics. Serine carbapenemase production (50 %) was the most frequently detected by phenotypic tests which is produced certain variants of –lactamase GES. Comparison of macrorestrictions profiles showed a high diversity among isolates represented by 20 different clusters, the related isolates originated from the same location. Wastewaters play a key role in the spread of antibiotics resistance. In this thesis, Enterobacter spp. strains with clinically significant resistance to cephalosporins and carbapenems were detected. These strains were detected mainly in hospital wastewaters but also in WWTP effluent. The current WWTP processes are unable to eliminate all bacteria that subsequently enter the environment.
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Evaluation of antibiotic-induced mitochondrial superoxide production in adherent cells
Ingrová, Kateřina ; Chmelíková, Larisa (referee) ; Zumberg, Inna (advisor)
The theoretical part of this bachelor´s thesis contains a description of the effect of reactive oxygen species on oxidative stress by mitochondria and the consequences of antibiotics use in cell line culturing. The cell line studied in this bachelor´s thesis is the mesenchymal stem cells (MSCs). The practical part describes the procedure of the experiment including cell culturing, passaging and cell labeling. The proposed experiment was repeated with sufficient number of repetitions. Finally, confocal microscopy images were processed in the MATLAB programming environment.
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Determination of selected drugs in water
Tran Xuan, Tiep ; Tulková, Tereza (referee) ; Vávrová, Milada (advisor)
Submitted thesis tackles the problem of numerous of antibiotics in waste water. Specifically, trimethroprim azithromycin and clarithomycin. In all of those cases we are dealing with a massive ecological threat at hand, causing harm to the enviroment. To isolation the specific kind of antibiotics the method of SPE was chosen by prior consultation with the supervisor. The method of high performance liquid chromatography with mass spectrometry detection was deemed superrior for the pinpointing of the exact pharmaceuticals in waste watters. The waste waters in and out flow was observed for twelve days with the maintainance of all necessary procedures listed above at water treatment plants Brno-Modřice.
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Analysis of secondary metabolites from Streptomyces by Raman spectroscopy in vivo
Mikulová, Adéla ; Petříčková, K. ; Bobek, J. ; Chroňáková, Alica ; Samek, Ota ; Pilát, Zdeněk
The work deals with the study of Raman spectra of secondary metabolites of bacteria of the genus Streptomyces, especially polyene antifungal agents. Purified isolates and commercial standards of these compounds were used to obtain reference spectra from which spectral markers characterizing specific details of the chemical structure were derived. Verification of the observed markers was performed using in silico Raman spectra predictions. Subsequently, these findings were used for the spectroscopic characterization of the composition of secondary metabolites in vivo, directly in bacteria growing on a solid medium. The developed methodologies will help to optimize the conditions for the biotechnological production of antibiotics.
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Antimikrobiální rezistence a její šíření v potravinovém řetězci
Maršová, Nikol
The bachelor thesis deals with the resistance of microorganisms to antimicrobial agents and its subsequent spread in the food chain. It focuses mainly on the resistance of microorganisms to antibiotics, in relation to the types of antibiotics according to their chemical structure and their mechanism of action. It describes the basic principles of agents used against viruses, yeasts, fungi and parasites. Characterises the nature of the emergence and mechanisms of resistance. It also discusses the methods used to determine the resistance of microorganisms to antimicrobial agents. Describes when resistance of microorganisms began to emerge historically and its occurrence in different sections of the food chain. In relation to the spread of antimicrobial resistance in the food chain, it describes the most serious zoonotic agents today.
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Vláknité mikromycety (plísně) a jejich biotechnologické využití
Beniačová, Michaela
The bachelor thesis focuses on filamentous micromycetes and their biotechnological utilization. This paper describes the nutrition, morphology, sexual and asexual reproduction of filamentous micromycetes and the optimal conditions for their growth and habitat. Following sections also contain the taxonomic distribution and characteristics of important species along with their short morphological description. The second part of the thesis categorizes and describes biotechnologies, following usage of filamentous micromycetes in the food, agricultural and pharmaceutical industries. Furthermore, this part touches utilization for environmental protection and use of industrially made substances produced by the metabolism of fungi.
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Antibiotická rezistence patogenních bakterií u vybraných druhů zájmových zvířat
Kaliská, Tereza
Some strains of pathogenic bacteria are capable of resistance to antibacterial agents. This resistance makes it difficult to treat diseases in both human and veterinary medicine. The most well-known pathogens of domestic animals, mainly dogs and cats, are mentioned in the context of the bachelor thesis. The thesis highlights the importance of understanding the mechanisms of resistance. It describes mobile elements, the principle of efflux pumps and spontaneous chromosomal mutations. Prevention should be the basis for preventing resistance from spreading further in the population. The observance of good hygiene habits, the appropriate use of antibiotics in the correct dosage and legislative adjustments on agricultural farms should be implemented on a global scale. The development of antimicrobial substances, including chemotherapeutics, should continue. At the same time, more empha-sis should be placed on the search for new alternatives. Mainly plant phytobiotics look promising.
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Detail analysis on antibiotic and heavy-metal resistance genes and horizontal gene transfer traits in anaerobic bacteria
Vancová, Kateřina ; Schwarzerová, Jana (referee) ; Čejková, Darina (advisor)
This thesis deals with a detail analysis on antibiotic and heavy-metal resistance genes and horizontal gene transfer traits in anaerobic bacteria. Antimicrobial resistance (AMR) in bacteria is a growing threat to public health globally. In these bacteria, AMR genes are often associated with mobile genetic elements (MGEs), which promote their mobility, enabling them to rapidly spread throughout a bacterial community. The work describes the horizontal gene transfer, the issue of antimicrobial resistance and the database for the detection of AMR genes and MGEs. After that, the detection and analysis of AMR genes and MGEs in anaerobic bacteria was done. Almost half of them contained at least 1 gene coding for antibiotic or heavy-metal resistance, 112 different genes overall. Then, 66 different MGEs were detected, 4 of which carried 6 different AMR detected genes.
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Detail analysis on antibiotic and heavy-metal resistance genes and horizontal gene transfer traits in anaerobic bacteria
Vancová, Kateřina ; Schwarzerová, Jana (referee) ; Čejková, Darina (advisor)
This thesis deals with a detail analysis on antibiotic and heavy-metal resistance genes and horizontal gene transfer traits in anaerobic bacteria. Antimicrobial resistance (AMR) in bacteria is a growing threat to public health globally. In these bacteria, AMR genes are often associated with mobile genetic elements (MGEs), which promote their mobility, enabling them to rapidly spread throughout a bacterial community. The work describes the horizontal gene transfer, the issue of antimicrobial resistance and the database for the detection of AMR genes and MGEs. After that, the detection and analysis of AMR genes and MGEs in anaerobic bacteria was done. Almost half of them contained at least 1 gene coding for antibiotic or heavy-metal resistance, 112 different genes overall. Then, 66 different MGEs were detected, 4 of which carried 6 different AMR detected genes.
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