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Thorium as an environment stressor for plant growth.
Hrdinová, Aneta ; Lhotáková, Zuzana (advisor) ; Podlipná, Radka (referee)
Thorium is an element belonging to heavy metals, which is characterized by its radioactivity similarly to uranium and radon. Thorium is not commonly used in industry, but becouse of its radioactive properties it has a great potentional for future use in nuclear energetics. Thus, increasing release of Th into the soil, water and atmosphere can be expected in near future and through plant biomass it could become a part of food chains and webs and, thus, to represent a considerable health risks to humans. Studies devoted to research on thorium and its effects on plants has not been published much yet. The majority of these studies focus mainly only on plant abilities to accumulate thorium and/or monitoring distribution of thorium in plant body. But till now, a study is still missing, which would monitor the effect of thorium on the physiological characteristics of plants. Plants of Nicotiana glutinosa (L.) medium Thorium accumulatin were hydroponically cultivated Hoagland nutrient media differedin the presence of thorium, tartaric acid, putrescine and phosphates. In first part of the present study I monitored accumulation of thorium by tobacco plants under the influence of the above-mentioned modifications of media. In the second part, I studied the Th effect on the photosynthetic apparatus (contents...
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Selective protection of pentaerythrityltetraamine
Mangl, Ondřej ; Hermann, Petr (advisor) ; Kotek, Jan (referee)
Selective protection of functional groups is a commonly used method which is used in multistep synthesis. Pentaerythrityltetraamine (PEA) is substance with four amino groups and substances with one to three selectively protected amino groups were prepared. Protections by t-butyloxycarbonyl (Boc) which is stable under neutral and basic conditions and can be deprotected in the acidic conditions, and with benzyloxycarbonyl (Cbz) which is stable under acidic and basic conditions and can be eliminated by hydrogenation was tested. Separation and purification of the protected amines was done by chromatography. Selectively protected PEA can be also prepared by indirect path by stepwise reduction of pentaerythrityltetraazide. Pentaerythritylmonoamine-triazide is prepared two-phase reduction and the amino group of the monoamine is protected with Boc or Cbz.
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Thorium accumulation and study of stress responces of plants on thorium presence
Kufner, Daniel ; Soudek, Petr (advisor) ; Petrová, Šárka (referee)
The ability of the accumulation of thorium and study of the stress responses on his presence was tested on a selected cultivar of tobacco, La Burley 21. Plants were cultivated in Hoagland's hydroponic medium under artificial light. Except to the ability of accumulation and distribution of thorium in the all parts of plant was investigated the effect of selected organic and inorganic additions on accumulation. Among organic substances included citric acid, tartaric and oxalic acid in their presence was observed the increase of thorium in all parts of the plant. Were also tested products from the diamine and polyamines (putrescine, cadaverine, spermine and spermidin). These substances, also known for their antioxidant activity in plants, had an impact on reducing the accumulation of thorium, especially in the root system of plants. The most important factor influencing the accumulation of thorium was the absence of phosphate ions in a hydroponic medium, which caused the rise of the concentration of thorium about several levels in all parts of the plants. The initial decrease of pH after additions of organic acids or addition of high concentrations of thorium and the gradual increase of pH during cultivation had proved significant. It was also compared the uptake of accumulation and distribution of...
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The formation of biogenic amines in flesh of selected fish species
MATĚJKOVÁ, Kateřina
The thesis deals with the use and effectiveness of some less common methods of conservation of fish meat. The formation of biogenic amines in meat is observed in connection with the non-traditional preservative methods. Amines can serve as indicators of protein degradation. The quality of fish was considered in connection with the increasing content of selected biogenic amines (putrescine, cadaverine, spermidine, spermine, 2-fenylathylamine, histamine, tyramine and tryptamine). Ultra performance liquid chromatography (UPLC) was used as the method for determination of biogenic amines. Amines were derivatized by dansylchloride before their UPLC separation. The fish flesh was vacuum-packed. Samples were stored for several weeks in a thermostat at the selected storage temperature after the application of selected preservative technique. Beta-irradiation and high hydrostatic pressure were used for the preservation of fish flesh. Control samples were not exposed to the â-irradiation and high pressure. The organoleptic properties were studied for all samples (smell/odor, insight and shape). Beta-irradiation was applied to fish meat of common carp (Cyprinus carpio) and rainbow trout (Oncorhynchus mykiss). Both these species of freshwater fish are economically significant. Carp and trout are the species being mostly consumed in the Czech Republic. Fish meat is considered to be provided the flesh is fresh. A testing series of samples was created with common carp to determine the appropriate dose of â-irradiation. The maximum permissible dose of irradiation for fish meat is 3 kGy. Fish samples were exposed this dose in the first experiment. The dose of irradiation was reduced in following experiments based on the experience from the initial experiment. The doses of 0.25, 0.5, 0.75, 1.0 and 2.0 kGy were applied to rainbow trout. The value of 0.75 kGy of â-irradiation or higher (1.0, 2.0 and 3.0 kGy) prolonged the shelf life of fish meat, which was stored for three months (98 days). Prolonging of the shelf life of fish meat to approximately 98 days at 3.5 °C is redundant from technical point of view. For that reason lower doses 0.25, 0.5 and 0.75 kGy were tested in more detail in the repeated experiment with carp meat. Lower doses of â-irradiation are considered to be more acceptable and-at the same time-sufficiently effective for delaying the beginning of degradation processes. 6 High hydrostatic pressure was applied to meat of common carp (Cyprinus carpio), rainbow trout (Oncorhynchus mykiss) and pike (Exos lucius). Pike is another very popular kind of freshwater fish. Pike flesh is very tasty, but in spite of this, pike is not so much popular among consumers compared to carp and trout. The cause is its high price. Samples of pike were stored at standard temperature 3.5 °C and also at higher temperature 12 °C (unlike experiments with â-irradiation). Lower temperature of storage (3.5 °C) followed the conditions of storing of fish meat in industrial refrigeration facilities and households. The high pressure might not be sufficient for preservation at higher storage temperatures. This assumption was based on available information. Samples were treated by high pressure and stored at both 3.5 °C and 12 °C to verify this assumption. Higher temperature simulated either failure of refrigeration equipment or unsuitable store temperature of meat. In all species selected freshwater fish two levels of high pressure were applied ? 300 and 500 MPa. Both levels had significantly reduced the formation of biogenic amines, especially in samples stored at 3.5 °C. At this temperature, the effect of 300 and 500 MPa delayed start of degradation processes in fish meat by 3?4 weeks. At 12 °C and 500 MPa, high pressure extended the sustainability of meat by no more than one week. 500 MPa is effective treatment at the lower temperature of 3.5 °C. High pressure is not reliable preservative techniques at higher temperature.
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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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Changes of biogenic amines and polyamines content during storage and heat treatments of mutton.
LÍSKOVCOVÁ, Lucie
The aim of this thesis was to determine the content of biogenic amines and polyamines, specifically putrescine (PUT), spermidine (SPD) and spermine (SPM) in mutton meat during storage and heat treatment. The meat of slaughter animals is rich in these amines but, unfortunately, data on the content of mutton meat whether in slaughter bodies as well as during storage or heat treatments in the literature are still missing. The samples were provided by small farmers and the animals were hybrids of several breeds. The samples were taken from the thigh and back. The samples of lamb meat were frozen and the ones were watched from 0-6 months. The samples of leg were cooled and packed into three different types of packaging. It was the type of packaging in a polyethylene bag (PE), vacuum packed (VP) and controlled atmosphere packaging (MAP). All the samples were analyzed in the days and also on the initial concentration at day 0. For frozen and cooled (chilled) samples which were stored in PE and VP was observed the decrease in all monitored amines. Only the packaging in MAP occurred in the SPD to a slight increase over the initial content. From heat treatments were performed usual preparations of the meals which are made in central Europe and the meals were cooked on particular days. The highest decrease was measured in roasted meat, then stewed and cooked meat in this order. Reported data are comparable to published data for pork and beef meat stored under the same or similar conditions. I think that these data can help to extend the data in the literature.
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Content of biogenic amines and polyamines in expired ripening cheeses
VODEHNALOVÁ, Klára
The aim of this thesis was to observe the occurrence of biogenic amines and polyamines in selected types of ripening cheeses and to assess the content of the materials since the expiration date. Content of biogenic amines and polyamines in chosen samples was monitored last day of the expiration date, a week after the expiration date, two weeks after the expiration date, and after four weeks from the end of the expiration date.
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Content of biogenic amines and polyamines in mutton.
LÍSKOVCOVÁ, Lucie
The aim of the bachelor thesis was to determine content of biologically active biogenic amines and polyamines in mutton and lamb meat. There are not too many consumers of mutton in the Czech Republic. This kind of meat is consumed mostly during Easter, while in Anglo-Saxon countries it has been a sought-after food resource. World{\crq}s mutton yearly consumption has been about 2 kg per capita. In the Czech Republic it is only 0.4 kg. Meat of slaughter animals is rich in biogenic amines and polyamines, especially in spermine (SPM) and spermidine (SPD). Their contents in beef, pork and chicken meat have been determined previously. Literature data on mutton and lamb has been lacking for polyamines and information on biogenic amines has been very scarce. Liquid chromatography method in UPLC arrangement was used for the determination of putrescine (PUT), cadaverine (CAD), tyramine (TYR), phenylethylamine (PEA), histamine (HIM), tryptamine (TRM), SPD and SPM, the amines with considerable biological effects. Mutton and lamb loin (19 and 20, respectively) and leg (17 and 20, respectively) were analysed 24 hours after slaughter The samples originated from various minor breeders and they were hybrids of several breeds. The highest mean content was determined in mutton leg (32.53, 5.91 and 2.45 mg kg-1 of SPM, SPD and PUT, respectively), followed by lamb leg (17.25, 4.22 and 2.04 mg kg-1 of SPM, SPD and PUT, respectively). The respective mean contents in mutton loin were 17.22, 3.99 and 2.38 mg kg-1 and those in lamb loin 16.54, 5.08 and 2.11 mg per kg. Lamb loin was the only meat with detected TYR. Histamine was present only at trace levels, amines TRM, PEA and CAD were not detected in any samples. The determined contents are comparable with published data for beef and pork.
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