Mikromicetai yra labai įvairi, gyvybinga, aktyvi, įvairiomis veiklos galiomis pasižyminti mikroorganizmų grupė, gebanti aktyviai sintetinti ir išskirti įvairios cheminės prigimties metabolitus. Toksikologiniu ir cheminiu atžvilgiu tai yra heterogeniška medžiagų grupė, kurią sunku klasifikuoti ir apibūdinti. Mikotoksinai aptinkami tiek gyvulių pašare, tiek ir žmonių maisto produktuose. Jie sukelia įvairius žmogaus bei gyvūnų sveikatos sutrikimus. Toksinis šių junginių aktyvumas siejamas su jų chemine struktūra. Darbas skirtas mikotoksino deoksinivalenolio toksinio poveikio tyrimui, panaudojant dvi modelines tyrimo sistemas - laboratorinius gyvūnus (in vivo) ir ląstelių kultūras (in vitro). Deoksinivalenolis - dažniausiai Fusarium genties mikromicetų produkuojamas metabolitas, savo struktūroje turintis epoksido grupę, kuri, manoma, ir lemia jo toksiškumą. Panaudojus laboratorinius gyvūnus (peles), kaip tradicinę toksikologinių tyrimų sistemą in vivo, nustatėme, kad deoksinivalenolis po 14-kos parų kasdienio 15 µg/kg koncentracijos poveikio nesukėlė pastebimų organizmo pakitimų, gyvūnai buvo žvalūs, smalsūs, jų svoris augo. Tačiau po išsamesnių tyrimų buvo registruoti kraujo pakitimai, IgA koncentracijos padidėjimas. Panaudojus kitą modelinę toksinio poveikio tyrimo sitemą - ląstelių analizę kultūroje in vitro - nustatėme, kad labai mažos (5 ir 10 µg/ml) tiriamo mikotoksino koncentracijos sukėlė ląstelių pažeidimus. Šiame darbe deoksinivalenolio toksiškumo tyrimui mes... [toliau žr. visą tekstą] / Our study is devoted to the analysis of mycotoxin deoxinyvalenol toxicity and comparison of toxicity tests in the model systems in vivo and in vitro. It is known that mycotoxin-producing mold species grow on a wide range of substrates under a wide range of environmental conditions, they are pharmacologically active mold metabolites characterized by vertebrate toxicity. They fall into several chemically unrelated classes, are produced in a strain-specific way and vary in specificity and potency for their target organisms, organs or cells. We have used two model systems for the analysis of deoxinyvalenol effect. One of them is laboratory animal (mice) study or test system in vivo. It is as a traditional method for the evaluation of the toxic substances. We have found that animal diet containing 15 µg/kg deoxynivalenol during short-term (14 days) repeated toxicity test didn‘t influence noticeably animal health. Such small concentration of tested mycotoxin did not appear to depress animals, they were alive and curious, animal weight didn‘t fall behind control. Howewer, at the end of experiment we have found the decrease of mice blood parameters and dramatic increase of Ig A concentration in blood serum. Another test system used in our study was cell culture or test system in vitro. We have used permanent cell lines and newly established primary tissue culture cell lines, derived from potential mycotoxin-target organs: renal and lung. The results presented in this study describe... [to full text]

Highly acidic environments represent some of the most extreme habitats for the microbial growth. For a long time it has been assumed that these sites are populated exclusively by prokaryotes. However recently, eukaryotic organisms including fungi have been found to be abundant and important component of acidophilic communities. Concerning fungal diversity only fragmentary data are available indicating that highly acidic sites harbour specific and low-diversified fungal communities dominated by dematiaceous fungi. In the present work we focused on the cultivable mycobiota occupying highly acidic (pH < 3) soils which are at the same time saline (sulfate-rich) and are located at geographically isolated localities in the Czech Republic. This study should provide a deep insight into the diversity and biogeographical pattern of acidophilic/tolerant fungi. A combination of classical and specialized cultivation techniques was successfully applied since it significantly contributed to the broadening of the detected fungal spectrum. The revealed fungal assemblages inhabiting highly acidic sites worldwide are closely similar and differ from the ones known from less acidic habitats. The core of the fungal assemblage under study consisted of phylogenetically unrelated and often globally distributed fungi...

Darbo objektas: pašariniai kviečiai bei miežiai. Kviečių ir miežių mėginiai buvo gauti iš Prienų rajone esančių žemės ūkio įmonių. Mėginiai paimti atsitiktinės atrankos būdu iš saugyklų. Eterinių aliejų antigrybinis aktyvumas įvertintas difuzijos į agarą metodu. Darbo apimtis: 69 puslapių. Darbe pateiktos 9 lentelės, 16 paveikslų. Darbo tikslas: įvertinti eterinių aliejų antigrybines savybes mikromicetams, išskirtiems iš grūdų. Darbo uždaviniai: atrinkti komercinius eterinius aliejus pagal jų poveikį, sumažinant grūdų užsikrėtimą mikromicetais. Įvertinti atrinktų komercinių eterinių aliejų antigrybines savybes „lauko“ mikromicetams. Įvertinti atrinktų komercinių 100 proc. eterinių aliejų antigrybines savybes „sandėlių“ mikromicetams. Palyginti komercinių eterinių aliejų antigrybines savybes skirtingoms mikromicetų rūšims. Rezultatai ir aptarimas: Atrinkti 6 komerciniai eteriniai aliejai (raudonėlių, šalavijų, ciberžolių, čiobrelių, pipirmėčių ir levandų), pasižymintys antigrybinėmis savybėmis. Vertinant eterinių aliejų antigrybinį poveikį, parinktos keturios pagrindinės mikromicetų kultūros (Fusarium sp., Penicillium sp., Aspergillus sp., Alternaria sp.). Mikromicetų kultūras, veikiant skirtingu eterinių aliejų kiekiu (50; 25; 12,5; 6,25 μl), EO mažiausiai turėjo įtakos Aspergillus genties grybams. Fusarium genties grybai buvo jautriausi 50 ir 25 μl eterinių aliejų kiekiui. Mažinant eterinių aliejų kiekį (12,5 ir 6,25 μl) jautriausi antigrybiniam poveikiui buvo Penicillium... [toliau žr. visą tekstą] / Object of the thesis: feeding wheat and barleycorn. Samples of wheat and barleycorn were obtained from agricultural companies in Prienai district. Samples were taken from storage by random selection. Antifungal activity of essential oils was evaluated using method of diffusion to agar. Structure: 69 pages. There are 9 tables and 16 figures in the thesis. Objective of the thesis: to evaluate antifungal effect of essential oils on micromycetes isolated from grain. Tasks: to select commercial essential oils according to their effect, by decreasing infection of grain with micromycetes. To evaluate antifungal effect of selected commercial essential oils on micromycetes "outside". To evaluate antifungal effect of selected commercial 100% essential oils on micromycetes "in storage". To compare antifungal effect of commercial essential oils on different kinds of micromycetes. Results and discussion: 6 commercial essential oils (oregano, salvia, curcuma, thyme, peppermint and lavender) with antifungal properties were selected. When evaluating antifungal effect of essential oils, four main cultures of micromycetes were selected (Fusarium sp., Penicillium sp., Aspergillus sp., Alternaria sp). When applying different amounts of essential oils on cultures of micromycetes (50; 25; 12,5; 6,25 μl), the smallest effect was that of EO on genus Aspergillus fungi. Fungi of genus Fusarium were the most sensitive to the essential oil amounts of 50 and 25 μl. As the amount of essential oils was... [to full text]

Microscopic fungi (micromycetes) is a topic that is at lower secondary schools neglected and mentioned only marginally. Fungi are of great importance for humans in their everyday life, whether negative or positive. It is the reason to rethink how and when to inform pupils about them. The aim of my thesis is to create my own practical exercises that acquaint the pupils of lower secondary schools with the appearance, properties, occurrence, uses, cultivation methods, and last, but not least with the safety of micromycets. In the practical exercises are used basic methods of work with micromycets such as inoculation of the population from the natural environment to a sterile culture medium, the sedimentation method or the method of spreading a dilute suspension of the stick on the agar medium. The revaccination is used to eliminate secondary structures. Then we deal with the possibility of preparing culture media. Isolated cultures of microscopic fungi are identified by macroscopic characters. Due to the safety with micromycets, I recommend to teach microscopic characteristics in high school. The presented practical exercises were verified at the lower secondary school in Vinařice by pupils of the 6th class. The practical exercises proved to be suitable for pupils in lower secondary school. Securing...

Filamentous microfungi play an important role in the environment and they can have either a positive impact on a man, e.g. in a form of medicine or food production, or a negative one, when filamentous microfungi may cause diseases or deteriorate food. Pupils usually start learning about filamentous microfungi in form 6 of a primary school, or they get some tangential information in the first year of an eight-year grammar school. In addition, in most of student's books, microfungi are incorrectly referred to as moulds, which is an unprofessional term. The objective of my thesis is to elaborate two practical tasks for the presence form of study in which pupils find out the difference between unicellular and multicellular fungal organisms, acquaint themselves with the fungal phytoparasite - mildew, take the substrate, make native and coloured mounts which are then observed under the microscope. The other two practical tasks have been elaborated for the distance form of study via exploration tasks, which can be carried out at home conditions. It means creation of a mycological garden and observation what kind of bakery products is more prone to be affected by microfungi. The other elaborated tasks relate to across-the-curriculum use of the filamentous microfungi topic in Maths and Czech, in which some...

Diploma thesis deals with relationship between the sustainability of buildings and indoor climate. The aim of the diploma thesis was to design the air conditioning system for operating theaters. In the experimental part the aim was to provide total microorganisms counts and total count of micromycetes on samples taken from filters. The work is divided into three parts: theoretical, design and experiment.