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Ecotoxicological evaluation of sediments
Dobešová, Zuzana ; Doležalová Weissmannová, Helena (referee) ; Zlámalová Gargošová, Helena (advisor)
Sediments of lotic and lentic water can be a reservoir of a number of contaminants, which can enter the aquatic ecosystem either due to the controlled discharge of waste water or leakage of various accidents or technological devices. Sediments can hereby affect not only the aquatic ecosystem, but also the terrestrial system in the case that they will be used as fertilizer or as a material for the recultivation. For this reason it is important to consider their potential ecotoxicity. Sediments were subjected to ecotoxicological bioassays and their potential ecotoxicity was assessed. The phytotoxicity assays on terrestrial plants Sinapis alba, Lactuca sativa and Allium cepa were used and the effects of aqueous extracts of sediments on the inhibition of growth their root were evaluated and the value of IC50 was determined. For the ecotoxicological assessment of sediments and determination of IC50 value also Lemna minor as a representative of aquatic plants was selected. For more objective assessment of the sediment ecotoxicity aquatic invertebrates as Artemia salina and Daphnia magna were selected and the value of LC50 or EC50 was determined.
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Residues of inhibitors in cow´s milk
STŘELEČKOVÁ, Veronika
Milk, in our territory frequently used cow?s milk, is very important nutrient. Its importance consists in the contents of valuable proteins, easily digestible milk fat, lactose, vitamins and minerals. The quality of raw cow?s milk is characterised by many indicators, for example total number of microorganisms, number of somatic cells, content of basic constituents (fat, protein, lactose, non-fat solids), freezing point or occurrence of undesirable foreign and inhibitory substances. Residuals of inhibitory substances (RIL) are one of the main criteria of raw milk hygienic quality, where they can appear for example due to prevention and treatment of mastitis. The risk of occurrence and spread of bacterial resistance, disruption of intestinal microflora, allergic reactions and RIL toxic effects, both in human and veterinary medicine, belong among the biggest risks of RIL presence in food and raw materials of animal origin, including milk. Inhibitory substances have an inhibiting effect on development and activity of microorganisms and in particular in milk industry they affect the activity of dairy cultures causing significant production problems. Their presence in milk causes problems when producing cheese, during fermentation of yoghurts and other fermentation during milk processing. Prevention of RIL occurrence depends especially on adherence to basic breeding and veterinary measures when using drugs and medicines, on technology discipline in primary production and regular and strict control of RIL contents in milk from the primary production up to processing when various screening detection methods are used. It is very important to deal with the matter of RIL in milk in connection with quality standards, national legislation and European Union legislation and to control methods used for their detection and verification.
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The main extraneous substances ingestion by nutriment
BUCHAROVÁ, Eva
This work treats of main extraneous substances ingestion by nutriment. It means additives and contaminants. Present of this substance in food is regulated by legislation. In Czech Republic, there are, laws of food in accordance with laws of EU. In Czech Republic, there are, additives and contaminants controlled by SZPI and SVS. European control institution is EFSA and throughout the world works FAO/WHO. Chief aim of this work is to find out differences in foreknowledge of the main substances ingestion by nutriment between men and women.
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