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Biogenní aminy v produktech minipivovarů
SYMONOVÁ, Michaela
The bachelor thesis deals withbiogenic amines (BA) content in beers of selected microbreweries from South Bohemia, where beers from commercial breweries are also used for comparison. This thesis is divided into two parts. The first, theoretical part, is focused on introducing the brewing industry, the process of beer production, the difference in the production process in microbreweries and their characteristics. It also explains what BAs are and their different presentation. The second half of this thesis is focused on the experimental part, where the methodology of the work, determination and evaluation of BA content in different beer samples is presented. The ultraperformance liquid chromatography (UPLC) method by which the content of individual BAs in beer samples was determined is also presented. Subsequently, the results of the experiment are presented and a discussion with a comparison of the results of this work with the results of other studies of the same focus is presented.
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The determination of mycotoxins in commercial beers
Martiník, Jan ; Benešová,, Karolína (referee) ; Mgr. Marek Pernica, Ph.D (advisor)
Mycotoxins are secondary metabolites of microscopic fibrous micromycetes that are able to infect cereals. The use of contaminated materials can lead to transfer of mycotoxins into the final product, such as beer. The master’s thesis deals with the determination of mycotoxins in beers. The theoretical part of this thesis describes selected mycotoxins, their occurrence, toxic properties and legislative limits of the European Union. The theoretical part also deals with the description of beer production and the possibilities of mycotoxin determination. The theoretical part also describes the statistical methods used for data processing. The experimental part of this work describes the validation of the method for determination of mycotoxins in beers. This section also describes the optimization of mycotoxin extraction using a commercially available 11+Myco MS-PREP® immunoaffinity column. The conditions for the determination of mycotoxins on UPLC-MS/MS are given in this thesis. The validation parameters such as linearity, accuracy, precision, LOD and LOQ were determined. This section contains a description of beer samples used for the determination of mycotoxins. The goal of the thesis was to optimize and validate the method for determination of mycotoxins in beers. From the validation parameters, it was found that this method is suitable for its intended purpose, namely for mycotoxins aflatoxin B1, aflatoxin B2, aflatoxin G1, aflatoxin G2, fumonisin B1, fumonisin B2, fumonisin B3, ochratoxin A, ochratoxin B, zearalenone, -zearalenol, -zearalenol, -zearalanol, -zearalanol, deoxynivalenol, 3-acetyldeoxynivalenol, T-2 toxin and HT-2 toxin. The recoveries of this method ranged from 72,2 % to 100,0 %. The validated method was used for determination of above-mentioned mycotoxins in 89 beers. Of the total number of beers, 37 were produced in the Czech Republic and 52 in other European countries. Mycotoxins deoxynivalenol, T-2 toxin and HT-2 toxin were found in all beer samples. Common mycotoxins included fumonisin B1, ochratoxin A, -zearalenol and 3-acetyldeoxynivalenol. The mycotoxins aflatoxin B1, aflatoxin B2, aflatoxin G1, fumonisin B2, fumonisin B3, zearalenone and ochratoxin B were identified in less than 50 % of the samples. Mycotoxins aflatoxin G2, -zearalenol, -zearalanol and -zearalanol were not determined in any tested samples. The results of the analysis were subjected to statistical processing where the concentrations determined in Czech and European beers were compared. Principal component analysis and correlation analysis were created for aflatoxin B1, fumonisins, ochratoxin A, -zearalenol, deoxynivalenol, 3-acetlydeoxynivalenol, T-2 toxin and HT-2 toxin. The results of the analysis were compared with published studies.
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Mycotoxins in fermented beverages
Martiník, Jan ; Svoboda, Zdeněk (referee) ; Běláková,, Sylvie (advisor)
Mycotoxins are toxic secondary metabolites of mold and fungi that attack cereals, wine grapes or apples, which are then used to produce fermented beverages. This thesis focuses on mycotoxin patulin which is primarily found in ciders. The theoretical part describes selected mycotoxins, legislation concerning these mycotoxins and their occurrence in fermented beverages. Section of the theoretical part is also dedicated to the description of fermented beverages and analytical methods used to determine mycotoxins in beverages. The experimental part deals with the validation parameters of the method for determination of patulin and 5-HMF. It also deals with the extraction and determination of these substances. Columns EASIMIPTM PATULIN were used in the extraction of patulin and 5-HMF and the concentration was measured by ultra high performance chromatography with photodiode array detection (UPLC/PDA). The determination of patulin and 5-HMF was performed in a total of 33 samples of cider, 9 samples of apple juice, 2 samples of wine and 2 samples of radler. Patulin was found in 6,1 % of cider samples and in 44,4 % of apple juice samples. 5-HMF was found in both wines and radlers, in 78,8 % of ciders and in 77,8 % of apple juices. All measurement data is processed in the results and discussion. The results were compared with foreign studies.
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The determination of mycotoxins in commercial beers
Martiník, Jan ; Benešová,, Karolína (referee) ; Mgr. Marek Pernica, Ph.D (advisor)
Mycotoxins are secondary metabolites of microscopic fibrous micromycetes that are able to infect cereals. The use of contaminated materials can lead to transfer of mycotoxins into the final product, such as beer. The master’s thesis deals with the determination of mycotoxins in beers. The theoretical part of this thesis describes selected mycotoxins, their occurrence, toxic properties and legislative limits of the European Union. The theoretical part also deals with the description of beer production and the possibilities of mycotoxin determination. The theoretical part also describes the statistical methods used for data processing. The experimental part of this work describes the validation of the method for determination of mycotoxins in beers. This section also describes the optimization of mycotoxin extraction using a commercially available 11+Myco MS-PREP® immunoaffinity column. The conditions for the determination of mycotoxins on UPLC-MS/MS are given in this thesis. The validation parameters such as linearity, accuracy, precision, LOD and LOQ were determined. This section contains a description of beer samples used for the determination of mycotoxins. The goal of the thesis was to optimize and validate the method for determination of mycotoxins in beers. From the validation parameters, it was found that this method is suitable for its intended purpose, namely for mycotoxins aflatoxin B1, aflatoxin B2, aflatoxin G1, aflatoxin G2, fumonisin B1, fumonisin B2, fumonisin B3, ochratoxin A, ochratoxin B, zearalenone, -zearalenol, -zearalenol, -zearalanol, -zearalanol, deoxynivalenol, 3-acetyldeoxynivalenol, T-2 toxin and HT-2 toxin. The recoveries of this method ranged from 72,2 % to 100,0 %. The validated method was used for determination of above-mentioned mycotoxins in 89 beers. Of the total number of beers, 37 were produced in the Czech Republic and 52 in other European countries. Mycotoxins deoxynivalenol, T-2 toxin and HT-2 toxin were found in all beer samples. Common mycotoxins included fumonisin B1, ochratoxin A, -zearalenol and 3-acetyldeoxynivalenol. The mycotoxins aflatoxin B1, aflatoxin B2, aflatoxin G1, fumonisin B2, fumonisin B3, zearalenone and ochratoxin B were identified in less than 50 % of the samples. Mycotoxins aflatoxin G2, -zearalenol, -zearalanol and -zearalanol were not determined in any tested samples. The results of the analysis were subjected to statistical processing where the concentrations determined in Czech and European beers were compared. Principal component analysis and correlation analysis were created for aflatoxin B1, fumonisins, ochratoxin A, -zearalenol, deoxynivalenol, 3-acetlydeoxynivalenol, T-2 toxin and HT-2 toxin. The results of the analysis were compared with published studies.
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Determination of sibiromycin by UPLC method.
Fadrhonsová, Ivana ; Bosáková, Zuzana (advisor) ; Cajthaml, Tomáš (referee)
Sibiromycin is produced by actinomycetes of Streptosporangium sibiricum and structurally belongs to family of pyrrolo-1,4-benzodiazepines. Sibiromycin is characterized by antibacterial and especially antitumor activity but due to its proved cardiotoxicity it cannot be used. The following research of possible therapeutic sibiromycin utilization is concerned on new nontoxic derivatives produced by genetic manipulated strains of S. sibiricum. For this purpose a new routine chromatographic UPLC-UV method with analyte preconcentration was developed and partially validated. A fermentation broth was extracted by solid phase extraction (SPE) on OASIS MCX columns with the sorbent based on a cation-exchange. Eluted extract was evaporated, reconstituted in methanol and loaded onto UPLC BEH C18 column and analyzed under gradient mode with mobile phases of methanol (A) and trifluoroacetic acid (B). Detection limit of the method was determined as 40 ng/ml, the recovery was 74.75 % and its reproducibility expressed as RSD was 5.18 %. The method was applied to comparison of sibiromycin production by S. sibiricum on 13 different fermentation media. It was found, that a composition of fermentation media influences not only the sibiromycin production but also a synthesis of sibiromycin nature derivatives, which were...
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Mycotoxins in fermented beverages
Martiník, Jan ; Svoboda, Zdeněk (referee) ; Běláková,, Sylvie (advisor)
Mycotoxins are toxic secondary metabolites of mold and fungi that attack cereals, wine grapes or apples, which are then used to produce fermented beverages. This thesis focuses on mycotoxin patulin which is primarily found in ciders. The theoretical part describes selected mycotoxins, legislation concerning these mycotoxins and their occurrence in fermented beverages. Section of the theoretical part is also dedicated to the description of fermented beverages and analytical methods used to determine mycotoxins in beverages. The experimental part deals with the validation parameters of the method for determination of patulin and 5-HMF. It also deals with the extraction and determination of these substances. Columns EASIMIPTM PATULIN were used in the extraction of patulin and 5-HMF and the concentration was measured by ultra high performance chromatography with photodiode array detection (UPLC/PDA). The determination of patulin and 5-HMF was performed in a total of 33 samples of cider, 9 samples of apple juice, 2 samples of wine and 2 samples of radler. Patulin was found in 6,1 % of cider samples and in 44,4 % of apple juice samples. 5-HMF was found in both wines and radlers, in 78,8 % of ciders and in 77,8 % of apple juices. All measurement data is processed in the results and discussion. The results were compared with foreign studies.
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Isolation and characterisation of biologically active substances
Kettnerová, Eliška ; Nesměrák, Karel (advisor) ; Musilová, Adéla (referee)
This Bachelor thesis aims at isolation and partial identification of biologically active substances which are produced by actinomycetes and can be potentially applied in medicine. Cultivation broths of actinomycetes containing their metabolites were purified and pre-concentrated by solid phase extraction. Then, the bioassay of the extracts by Kirby-Bauer test using the sensitive strain Kocuria rhizophila was performed. Biologically active metabolites were analyzed and isolated by ultra- performance liquid chromatography with photo diode array detector. Isolated substances were assayed by mass spectrometry, which yielded relative molecular mass values of the unknown compounds. The values were compared with relative molecular masses of compounds listed in a chemical database, which involves natural products including antibiotics. We revealed that the unknown biologically active substances do not refer to any already discovered compound present in the database suggesting that the unknown compounds may be novel. More mass spectrometry and nuclear resonance experiments have to be carried out in order to elucidate their structure. Key words: actinomycetes, antibiotics, SPE, UPLC, HPLC Subject heading: analysis of secondary metabolites, bioassay test, isolation of biologically active compounds,...
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Determination of sibiromycin by UPLC method.
Fadrhonsová, Ivana ; Cajthaml, Tomáš (referee) ; Bosáková, Zuzana (advisor)
Sibiromycin is produced by actinomycetes of Streptosporangium sibiricum and structurally belongs to family of pyrrolo-1,4-benzodiazepines. Sibiromycin is characterized by antibacterial and especially antitumor activity but due to its proved cardiotoxicity it cannot be used. The following research of possible therapeutic sibiromycin utilization is concerned on new nontoxic derivatives produced by genetic manipulated strains of S. sibiricum. For this purpose a new routine chromatographic UPLC-UV method with analyte preconcentration was developed and partially validated. A fermentation broth was extracted by solid phase extraction (SPE) on OASIS MCX columns with the sorbent based on a cation-exchange. Eluted extract was evaporated, reconstituted in methanol and loaded onto UPLC BEH C18 column and analyzed under gradient mode with mobile phases of methanol (A) and trifluoroacetic acid (B). Detection limit of the method was determined as 40 ng/ml, the recovery was 74.75 % and its reproducibility expressed as RSD was 5.18 %. The method was applied to comparison of sibiromycin production by S. sibiricum on 13 different fermentation media. It was found, that a composition of fermentation media influences not only the sibiromycin production but also a synthesis of sibiromycin nature derivatives, which were...
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Vliv tepelných úprav kuřecích jater na změny obsahu biogenních aminů a polyaminů
Sultana, Michaela
This thesis examined the effects of different cooking methods (boiling, stewing and roasting) on chicken liver in order to measure changes in the levels of biogenic amines (BA) and polyamines (PA). Two other factors were also considered, season and method of chicken liver storage. BA and PA levels were determined using a liquid chromatography method (UPLC). The mean level of BA in the original raw material (six and three samples of refrigerated and frozen livers, respectively) was very low, with the highest being histamine (4,11 mg.kg-1). Tryptamine and fenylethylamin were not detected in any of the samples. The level of PA was significantly higher than the level of BA, with more spermine (135 mg.kg-1) than spermidine (42,3 mg.kg-1). The total content of BA and PA in the dry matter of refrigerated livers was almost twice as high in the summer than in the winter (P < 0,001). When comparing refrigerated against frozen livers, the levels of putrescine and histamine were significantly higher in the refrigerated liver (P < 0,01), while the levels of cadaverine and tyramine were higher in the frozen liver (P < 0,001), and the levels of spermine and spermidine were 20 % lower in the frozen liver (P < 0,01). Roasting had less of an effect in the decline of BA (80 % of the original content) than cooking (65 % of the original content) (P < 0,001). The lowest levels of spermine and spermidine were found in the roasted liver (70 % of the initial content) while stewing and cooking caused a decrease of approximately 80 % (P < 0,01).
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Changes of biogenic amines and polyamines content during storage and heat treatments of edible mushrooms.
PEKÁRKOVÁ, Jana
The target of this thesis was found content of eight biogenic amines and polyamines, specifically putrescine (PUT), spermidine (SPD), spermine (SPM), histamine (HIM), cadaverine (CAD), 2-phenylethylamine (PEA), tyramine (TYM) and tryptamine (TRM) in growed Agaricus hortensis during storage, frozen and heat treatment. There are many information dealing with these amines in the food in this time, but unfortunately data on the content of amines in edible mashrooms in literature are still missing. The samples were providing from company České houby a.s. in Soběslav. Those mushrooms were immediately processed. Frozen samples in PE sack (plastic bags) were tracked during three months. Boiled, blanched and raw samples of mushrooms were analysed in the beginning of concentration at day 0 and then 1, 2 and 4 days at 6 °C in the storage. Some samples of each experiment monitored after one day of storage at 22°C. Absolutely the highest concentrations found in all experiments with SPD. Changes in the content of amine modified and raw mushrooms during 4 days of storage at 6 ° C flow in both directions. The most important changes are visible immediately after blanching - a significant increase in TYM and even more pronounced in SPM. The increase was also showed in the content of the cooked mushrooms, in the SPD and to a higher volume in SPM. Storage at 22 ° C was mostly affected content PEA - the cooked mushrooms content significantly decreased, but blanched mushrooms increased. Also in raw mushrooms lead storage at this temperature for a significant increase in the SPM. Freezing substantially affect any of the amines. TRM and CAD analysis were not detected; HIM at lower limit was detected after cooking mushrooms and after storage of raw mushrooms at 22 ° C. I hope that the observed data can help extend the data in the literature and offers the opportunity to further focus of research in the field of biogenic amines in edible mushrooms.
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