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Determination of bisphenols in selected beverages by high-performance liquid chromatography
Marvan, Jiří ; Sobotníková, Jana (advisor) ; Olšovská, Jana (referee)
Bisphenols are chemical compounds with a wide range of uses in the chemical industry. They are used in the production of plastic materials as softeners for polymer materials or epoxy resins, as monomers in the synthesis of polycarbonates, or for the elimination of hydrochloric acid in the production of polyvinyl chloride. This thesis deals with the development, validation, and optimization of an analytical method for the determination of selected bisphenols, specifically bisphenol A, bisphenol B, bisphenol F, bisphenol A diglycidyl ether and bisphenol F diglycidyl ether (BPA, BPB, BPF, BADGE, BFDGE), and their metabolites using the high performance liquid chromatography with mass spectrometry, HPLC/MS, and the application of the method to real samples in selected canned beer samples. The following conditions were optimized for chromatographic separation. The Sigma-Aldrich discovery C18 column (150×2,1 mm, 5µm) was chosen. The mobile phase consisted of a mixture of mobile solvent A, which contained 0,05% ammonium hydroxide, and mobile solvent B, which contained of methanol. The flow rate of the mobile phase was 0,240 ml/min. The total analysis time was 22 minutes, using a 5 μl injection of the sample solution with gradient elution. Next, a partial validation of the method was performed, evaluating...
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Study on biodegradation of PCBs by white-rot fungi.
Kožená, Lenka ; Bosáková, Zuzana (advisor) ; Olšovská, Jana (referee)
The biodegradation of Delor 103, a commercial mixture of PCB congeners, was studied with eight strains of white rot fungi in two nutritive media: in mineral nitrogen limited medium (so called Kirk medium) and in complex Malt- extract glucose medium. The most efficient biodegradation was observed with the fungus Pleurotus ostreatus, where 99% of PCB congener sum was degraded after 42 days in both media. Bjerkandera adusta was able to degrade 89% of PCB congener sum within 42 days in complex medium. Irpex lacteus removed 70% of PCB congener sum within 42 days in Kirk medium. Other white rot fungi showed lower biodegradation ability, degrading only low chlorinated biphenyls. Further, urgent toxicity of samples was monitored during the Delor 103 biodegradation. P. ostreatus proved to be the most suitable agens for PCB decontamination as a significant reduction of toxicity in comparison with controls was observed during the PCB degradation. In case of other fungi, no reduction of urgent toxicity was observed showing a disadvantage of their use for PCB biodegradation. Activities of ligninolitic enzymes during biodegradation were also studied. In both media laccase activity was detected in Dichomitus squalens, Pycnoporus cinnabarinus and Trametes versicolor cultures. Ligninperoxidase enzyme activity was...
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Liquid chromatography methods for analysis of microbial secondary metabolites of bioactive nature
Tylová, Tereza ; Olšovská, Jana (advisor) ; Cvačka, Josef (referee) ; Sýkora, David (referee)
(EN) This work is focused on development of new analytical methods involving modern solid phase extraction (SPE) for sample purification and pre-concentration, state-of-art ultra high- performance liquid chromatography (UHPLC) for separation of analytes and detection using diode-array detection (DAD) and/or time-of-flight mass spectrometry (ToFMS). The major part of the results has been published in prestigious international journals. The relevant yet unpublished results are included in the thesis as well. Besides a model comparison of various column chemistries used for "ultra-high performance" separations, some meaningful applications were developed. While one part of applications deal with determination of antibiotics as environmental contaminants that are responsible for the development and spread of microbial resistance, the second part is concerned with analyzing and finding of potential natural source of novel antimicrobial agents that can be further used as new antibiotics. The first part of the thesis was focused on the determination of residual antibiotics in different matrices (liquid hog manure, wastewater, surface water). The mostly prescribed antibiotics in both human and veterinary medicine were chosen as analytes in this study employing analytical methods consisting of UHPLC-DAD and...
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Study on biodegradation of PCBs by white-rot fungi.
Kožená, Lenka ; Olšovská, Jana (referee) ; Bosáková, Zuzana (advisor)
The biodegradation of Delor 103, a commercial mixture of PCB congeners, was studied with eight strains of white rot fungi in two nutritive media: in mineral nitrogen limited medium (so called Kirk medium) and in complex Malt- extract glucose medium. The most efficient biodegradation was observed with the fungus Pleurotus ostreatus, where 99% of PCB congener sum was degraded after 42 days in both media. Bjerkandera adusta was able to degrade 89% of PCB congener sum within 42 days in complex medium. Irpex lacteus removed 70% of PCB congener sum within 42 days in Kirk medium. Other white rot fungi showed lower biodegradation ability, degrading only low chlorinated biphenyls. Further, urgent toxicity of samples was monitored during the Delor 103 biodegradation. P. ostreatus proved to be the most suitable agens for PCB decontamination as a significant reduction of toxicity in comparison with controls was observed during the PCB degradation. In case of other fungi, no reduction of urgent toxicity was observed showing a disadvantage of their use for PCB biodegradation. Activities of ligninolitic enzymes during biodegradation were also studied. In both media laccase activity was detected in Dichomitus squalens, Pycnoporus cinnabarinus and Trametes versicolor cultures. Ligninperoxidase enzyme activity was...
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