Fakulta agronomická / Faculty of AgriSciences
https://repozitar.mendelu.cz/xmlui/handle/20.500.12698/1237
2024-03-29T04:55:32ZEvaluation of variability of the content of alpha and beta acids in Czech bittering hop varieties (Humulus lupulus L.)
https://repozitar.mendelu.cz/xmlui/handle/20.500.12698/1862
Evaluation of variability of the content of alpha and beta acids in Czech bittering hop varieties (Humulus lupulus L.)
Nesvadba, Vladimír; Straková, Lenka; Fritschová, Gabriela; Olšovská, Jana; Charvátová, Jitka; Trnková, Sabina
Czech bitter varieties were evaluated between 2010 and 2022. Hop varieties displayed an average content of alpha acids between 10.24% w/w (Agnus) and 13.73% w/w (Gaia). Variability below 15%, proved good stability of alpha acids content in all tested bittering hops. All varieties showed a decrease in the content of alpha acids over a period of 13 years of hop cultivation. The highest content of beta acids was determined in Gaia (7.30% w/w). In contrast, the lowest content of beta acids was found in Rubín (3.73% w/w). The new bitter genotypes Uran and 5304 had an average alpha acid content of 11.56% w/w and 10.82% w/w, respectively. Uran showed an average beta acid content of 5.47% w/w and for the genotype 5304 it was 3.61% w/w. In terms of the alpha/beta acids ratio, the hop varieties can be divided into three groups. The first group included the varieties with an alpha/beta acids ratio below 2, i.e. Vital, Boomerang and Gaia. While Agnus and Uran displayed an alpha/beta ratio slightly above 2. The highest alpha/beta ratio above 3 was found in Rubín and the 5303 genotype.
2023-01-01T00:00:00ZMesenchymal stem cells of Oravka chicken breed: promising path to biodiversity conservation
https://repozitar.mendelu.cz/xmlui/handle/20.500.12698/1859
Mesenchymal stem cells of Oravka chicken breed: promising path to biodiversity conservation
Svoradová, Andrea; Vašíček, Jaromír; Zmrhal, Vladimír; Venusová, Eva; Pavlík, Aleš; Bauer, Miroslav; Olexiková, Lucia; Langraf, Vladimír; Sláma, Petr; Chrenek, Peter
Mesenchymal stem cells (MSCs) are multilineage cells able to differentiate into other cell types. MSCs derived from bone marrow or compact bones are the most accessible stem cells used in tissue engineering. Therefore, the aim of this study was to isolate, characterize and cryopreserve MSCs of endangered Oravka chicken breed. MSCs was obtained from compact bones of the femur and tibiotarsus. MSCs were spindle-shaped and were able to differentiate into osteo-, adipo-, and chondrocytes under the specific differentiation conditions. Furthermore, MSCs were positive for surface markers such as CD29, CD44, CD73, CD90, CD105, CD146 and negative for CD34CD45 by flow cytometry. Moreover, MSCs demonstrated high positivity of "stemness" markers aldehyde dehydrogenase, alkaline phosphatase as well as for intracellular markers vimentin, desmin, α-SMA. Subsequently, MSCs were cryopreserved using 10% dimethyl sulfoxide in liquid nitrogen. Based on the results from the viability, phenotype and ultrastructure assessment we can concluded that the MSCs were not negatively affected by the cryopreservation. Finally, MSCs of endangered Oravka chicken breed were successfully stored in animal gene bank, thus making them a valuable genetic resource.
2023-01-01T00:00:00ZOptimization of the Plate Heat Exchanger Used for Milk Precooling
https://repozitar.mendelu.cz/xmlui/handle/20.500.12698/1857
Optimization of the Plate Heat Exchanger Used for Milk Precooling
Fryč, Jiří; Kudělka, Jan; Los, Josef; Koutný, Tomáš; Kebo, Vladimír
The article deals with the adjustment of the flow rate of milk and water by a plate heat exchanger, which is used for precooling milk. First, measurements of the parameters of the device in the stable were carried out. Subsequently, the plate heat exchanger was measured in the laboratory. Water at 35 oC was used instead of milk. Different flow ratios of cooling water and cooled water (instead of milk) were set. From the measured values, changes in the temperature of cooled water were calculated depending on its flow rate at a constant ratio of cooling water and cooled water. It was found that in the measured range, there are flow values at which temperature change is maximal. This dependence applies to all selected cooling water and cooled water flow ratios: (0.8, 0.9, 1.0, 1.1, 1.2.). The results show that with the same amount of cooling water, it is possible to achieve greater cooling of milk by 0.7 to 1.6 oC, or to achieve a reduction in water consumption. The device on the farm was modified to allow the flow of milk and cooling water to be changed. The optimal values found were set, and verification measurements were performed. The saving of 4.8% of cooling water was confirmed.
2023-01-01T00:00:00ZPlant-soil nitrogen, carbon and phosphorus content after the addition of biochar, bacterial inoculums and nitrogen fertilizer
https://repozitar.mendelu.cz/xmlui/handle/20.500.12698/1854
Plant-soil nitrogen, carbon and phosphorus content after the addition of biochar, bacterial inoculums and nitrogen fertilizer
Mikajlo, Irina; Pourrut, Bertrand; Louvel, Brice; Hynšt, Jaroslav; Záhora, Jaroslav
The use of biochar in combination with mineral or biological amendments to improve its influence on soil-plant properties has received growing attention. The changes of nitrogen, carbon and phosphorus content in Lactuca sativa var. capitata aboveground plant biomass and soil after the addition of beech wood biochar combined with the addition of bacterial inoculums (Bacofil and Novarefm) and nitrogen fertilizer have been studied using spectrophotometry methods. Pots were filled with the arable soil from the plots in the protection zone of water sources (Březová nad Svitavou, South Moravia, Czech Republic). Biochar with inoculums decreased plant growth in the first yield of Novaferm treatment and both yields of Bactofil treatment. Increased plant biomass growth was observed with Novaferm addition in the second yield. Total nitrogen increase has been obtained in the plant aboveground biomass and soil of the treatments amended with inoculums and nitrogen fertilizer. The decrease of phosphorus content has been observed in plant aboveground biomass in the biochar amended samples.
2023-01-01T00:00:00Z