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Antimicrobial activity of extract from GRAS plant species agains oral pathogenic microorganisms
Pilná, Jindřiška ; Kokoška, Ladislav (advisor) ; Jaroslav, Jaroslav (referee)
Microbial oral diseases such as caries and periodontitis are among the most frequent human infections. Conventional chemical antiseptics used for their treatment and prevention often produce adverse side-effects, which restrict their long-term use. Although plants are considered as perspective sources of novel antimicrobial compounds, little is still known about their inhibitory properties against oral pathogens and about their safety while used on a daily basis. The objective of this study was to investigate in vitro growth-inhibitory effects of ethanol Generally Recognised as Safe (GRAS) plant and supercritical CO2 hop extracts on planktonic cultures of cariogenic, periodontal and candidal human pathogens, namely Aggregatibacter actinomycetemcomitans, Bifidobacterium dentium, B. longum, Candida albicans, Eikenella corrodens, Fusobacterium nucleatum subsp. vincentii, Lactobacillus salivarius subsp. salivarius, Porphyromonas gingivalis, Streptococcus mutans, S. salivarius subsp. salivarius and S. sobrinus using the broth microdilution method. The findings showed that ethanol extracts of all 109 GRAS plant species inhibited the growth of at least one microorganism under study with minimum inhibitory concentration (MIC) equal or lower than 4096 ug/mL. However, only six of them possessed very interesting antiseptic potential against the oral pathogens with MIC < 100 ug/mL. Additionally, three GRAS plant species showed good inhibitory activity with MIC = 128 ug/mL. As far as the particular results are concerned, the best antiseptic effect was observed for both Humulus lupulus CO2 supercritical and ethanol extracts that inhibited the growth of all microorganisms at MICs higher or equal to 8 ug/mL and MICs higher or equal to 16 ug/mL, respectively. Hence, the CO2 supercritical extraction proved to be superior for extraction of active constituents of H. lupulus. Further, the ethanol extracts of Capsicum annuum and C. frutescens showed significant antiseptic potential against S. sobrinus and S. salivarius (MICs from 64 to 128 ug/mL). The oral streptococci were also inhibited by Zanthoxylum clava-herculis (MIC higher or equal to 64 ug/mL), Helichrysum angustifolium and Myristica fragrans (MIC higher or equal to 128 ug/mL) which further showed the antimicrobial activity against F. nucleatum (MIC = 64 ug/mL). Interesting inhibitory effects exhibited an extract of Punica granatum against C. albicans (MIC = 128 ug/mL) and F. nucleatum (MIC = 64 ug/mL). Moreover, the growth of F. nucleatum was inhibited by extracts of Pimenta officinalis and Thea sinensis (MIC = 128 ug/mL). The chemical analysis of the CO2 supercritical H. lupulus extracts revealed that alpha and beta bitter acids represented the two major groups of constituents. Cohumulone was the predominant compound of the alpha acids, whereas colupulone was the prevalent constituent of the beta acids. Our results suggest that the six GRAS plant species, namely C. annuum, C. frutescens, H. lupulus, M. fragrans, P. granatum and Z. clava-herculis have good potential to become new safe antiseptic agents that might be used for incorporation into oral care products such as toothpastes and mouthrinses.
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Maternal behaviour in Giraffes (Giraffidae)
Gloneková, Markéta ; Baranyiová, Eva (advisor) ; Luděk, Luděk (referee)
Allomaternal care is one of the most interesting types of cooperation among females. Its most extreme form is allonursing, nursing of a non-filial young, which is still not completely understood, even though many hypotheses have been postulated. This type of cooperation among giraffes had not been expected for long time. This was based on the initial opinion that giraffes do not have social system and form only weak social bonds. However, my bachelor and master theses showed high occurrence of allonursing in captive giraffes.
The first aim (1) of this thesis was to test all possible hypotheses explaining allonursing in captive giraffes. However, a lot of the information needed to test them were missing, which resulted in the formulation of further aims. The second aim (2) was to test the hierarchy in captive giraffes. The third aim (3) was to describe the growth and weight of captive giraffes. The fourth aim (4) was to compare nursing patterns in the zoo and in the nature reserve Bandia, Senegal and the last aim (5) was to test the social bonds among giraffes in the nature reserve Bandia, Senegal.
(1) From 2007 to 2011, the nursing behaviour of 24 females and 37 calves was observed. Eighty-three percent of the females allonursed a nonfilial calf and 86.5% of calves allosuckled from a nonmaternal female. Allonursing in giraffes was explained by milk-theft from the point of view of the calves and possible reciprocity among females. (2) The agonistic interactions of 31 giraffes were recorded in four herds. A linear hierarchy was been found among giraffes and rank was significantly affected by age and time spent in the herd. (3) The weight data from 43 giraffes in Prague zoo were collected from 2009 to 2013 and provided the basic information about giraffe growth and weight. (4) I also observed the nursing behaviour of seven and four female-calf pairs in the fenced Bandia reserve, Senegal, and in Prague zoo, respectively, both for 22 days. The differences in nursing patterns were likely to reflect anti-predator behaviour, the population density of animals and the distribution of food resources. (5) Finally, I investigated the social preferences of 28 introduced giraffes in semi-captivity in the nature reserve Bandia, Senegal and provided the results supporting the existence of a fission fusion social system among giraffes with social preferences among adult females.
The overall results provide unique findings on allonursing in general as well as changing our perspective on giraffe social behaviour.
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Postglacial colonization of black alder (Alnus glutinosa) and grey alder (Alnus incana) in Europe
Havrdová, Alena ; Mandák, Bohumil (advisor) ; Helena, Helena (referee)
Current species distribution in Europe was mainly influenced by massive climatic and environmental changes during the Quaternary period. Different theories concerning survival of tree species during the last ice age in Europe were proposed and up to date the position of glacial refugia and directions of migration routes are under active debate. My dissertation thesis aimed to combine information from fossil records and genetic analysis to improve knowledge on postglacial history of Alnus glutinosa and Alnus incana. The synthesis of palaeoecological data supports the idea that not only southern but also northern populations were important sources of postglacial Alnus expansion. The delayed Alnus expansion apparent in some regions was likely a result of environmental limitations. Our findings from molecular study showed differences in postglacial histories between temperate A. glutinosa and boreal A. incana. In the case of A. incana, we found an effective refugium in Central Europe located outside classical southern refugia confirming the existence of northern refugia for boreal trees in Europe. Fennoscandian populations are derived from Central-European ones that originated from populations in the Alps. For A. glutinosa, multiple southern refugia were revealed and three main directions of postglacial expansion were proposed: 1) from the northern part of the Iberian Peninsula to Western and Central Europe and subsequently to the British Isles, 2) from the Apennine Peninsula to the Alps, and 3) from the eastern part of the Balkan Peninsula to the Carpathians followed by expansion towards the Northern European plains. It has been shown that colonizing lineages have met several times and formed secondary contact zones with unexpectedly high population genetic diversity in Central Europe and Scandinavia. For the first time, we discovered tetraploid populations of A. glutinosa situated in the putative main glacial refugia on the Iberian and Balkan Peninsulas. Neither of them was probably involved in the colonization of Central and Northern Europe after glacial withdrawal. In conclusion, thanks to extensive population sampling, testing of hypothesis postulated based on fossil data by molecular data and using two molecular markers, i.e. chloroplast DNA and microsatellites, with different mode of inheritance and polymorphisms, this project revealed not only the position of glacial refugia of European tree species and discriminate between effective and non-effective ones, but also help infer the main migration routes. This approach enabled us to change some long-lasting paradigms and brought new pieces of knowledge about postglacial colonization of European tree species.
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Evaluation of the effect of radiation on evapotranspiration estimates and drought indices
Mairich, Pavel ; Matula, Svatopluk (advisor)
Abstract Evaluation of the effect of radiation on evapotranspiration estimates and drought indices The severity of drought can be inferred from water balance, of which evapotranspiration is a component. The evapotranspiration estimates are often based on the FAO 56 methodology with the net radiation as the main input. Usually, however, the latter is not directly measured. This study investigates to which extent can the direct solar radiation and the long-wave net radiation measurements be replaced by calculation according to FAO 56 with constant or locally optimised radiation coefficients or, for the long-wave net radiation, the coefficients according to Penman (1948). The problem is demonstrated on data from the Solar and Ozone Observatory in Hradec Králové for 2011 and 2012. On average, the estimates of solar radiation are satisfactory even with the standard coefficients and can be improved by local optimisation of the coefficients. The estimates for particular days may considerably differ from reality. The long-wave net radiation estimate according to FAO 56 is, on average, by about 30 % lower than the measured long-wave net radiation or an estimate thereof based on locally optimised or Penman's coefficients, with the average differences between any two of the last three methods much smaller (less than 9 %). The inaccuracy of estimates for particular days is considerable, too. The average reference crop evapotranspiration according to FAO 56 with standard coefficients is therefore considerably higher (by about 15 %) than analogous evapotranspiration obtained from the measured radiation or according to FAO 56 with optimised or Penman's radiation coefficients. The cause is that grass in the observatory was not irrigated. It therefore occasionally suffered from water stress and got overheated. The use of FAO 56 with the radiation inputs measured or calculated using other than the standard radiation coefficients may underestimate the evapotranspiration and the need for irrigation.
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The effect of long-term fertilizers application on soil chemical properties, plant species composition and arbuscular mycorrhizal fungi of grasslands
Zemková, Lenka ; Pavlů, Vilém (advisor) ; Hakl, Josef (referee)
Fertilization and liming of grasslands have been used as an instrument improving hay production for centuries. For a long period of time, these practices not only sustained and increased hay yields, but also had negative effects on grassland ecosystems. Among others, they caused considerable changes in plant species composition leading in most cases to the reduction of species richness due to a lower capability of indigenous plants to compete with more productive pasture species. Furthermore these practices caused changes in soil and biomass chemical properties and shifts of soil microbial communities, including arbuscular mycorrhizal fungi.
The aim of this thesis was to analyze the responses of plant and mycorrhizal community and soil chemical properties in grassland ecosystems to long-term application of nitrogen, phosphorus, potassium, and calcium. Results of this work indicate that agricultural management practices aimed at maximization of hay production may, in the long run, significantly increased hay yield, reduce plant species richness, promote grasses but suppress herbs, legumes and arbuscular mycorrhizal fungi in the soil although the response to phosphorus varied among different arbuscular mycorrhizal fungal taxa. Long-term fertilization also significantly changed soil chemical properties and considerably reduced belowground carbon storage.
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Qualitative and quantitative changes of agricultural land resources in the Czech Republic after 2000.
Gebeltová, Zdeňka ; Boháčková, Ivana (advisor) ; Jarmila, Jarmila (referee)
The main aim of the dissertation is to quantify changes in agricultural land use and propose some solutions to reduce or compensate for quantitative and qualitative degradation of the agricultural land resources in the Czech Republic. Data (WTO, FAO, CIMSC, RISWC, CSO, FADN) are processed by the geographic associations index, environmental stability index, regression and correlation analysis and multi criteria analysis. The quality of the agricultural land is decreased in southern Moravia and central Bohemia (Voltr, 2012).
The quality farmland is mainly reduced in agriculturally valuable soils, i.e. for soils with higher average official price. There is the largest quantitative loss of farmland above all in South-Moravian region and Zlín Region. A distinction of five soil quality classes is made. The large amount of land falls from the highest classes of protection in those two regions. The cultivation of certain crops (wheat, barley, canola, corn, perennial forage, permanent grassland) is located without scant regard for the production of soil conditions. It is not a good way from the agronomical perspective in the Czech Republic. Homogenization of arable crops and their range adversely can affect the long-term productive ability. Although above average high percentage of leased farmland is in the monitored regions, its influence on the GARE change was not statistically confirmed. The irrigation systems should affect the quality of agricultural land. However, the construction of new irrigation systems and the usability of many existing systems is economically limited and influenced by form of ownership too. Subsidies for the sustainability of the production capabilities of agricultural land (Rural Development Program) are paid not for prevention, but as result of erosion processes only. In the dissertation was created multi criteria analysis includes criteria, which can be potential causes reduction of the soil quality. They can simultaneously act on the degradation of agricultural land.
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Influence of Quality on Comipetitivity of Milk and Milk products
Hrubá, Renata ; Kovářová, Kateřina (advisor) ; Čechura, Lukáš (referee)
Globalization requires a new understanding of the effect of attitudes in the decision making process, particularly when regional differences arise from different cultural and social norms. Information behavior is the part of behavioral economics that explores decision making stakeholders - consumers, businessmen or politicians, under conditions of bounded rationality. For consumers it is primarily important to buy local products from family farms. The aim of the thesis was to verify the effectiveness of that model in the Czech Republic, especially to fill in the empirical aspect of behavioral economics, relating to consumer behavior under unclear information as well as normal environments, thus understanding the indirect effect of perception on product information. Today these issues are gaining in importance in developed countries as well as in the Czech Republic. The high probability of "never researching product information" resides more within consumers with negative attitudes toward global issues (30%) than in consumers with positive attitudes towards those issues (about 1%). Attitudinal changes affect decreases among those "never searching for product information" (by 30%) as well as increasing "search-rates" (by 60%). In other words, the changes in attitude have significant effects on consumer behavior (Spillover effect). Predicting decision making behavior under unclear information also shows important results. Changes of attitude toward nutrient security, milk of origin or ingredients is associated with relative changes in behavior. A change of attitude will reduce the probability to sometimes buy products with unclear (15%) and increases the probability of buying products with clear information (17%). Empirical research of behaviors under uncertainty are long-term projects, however methodologies may vary differentially. By connecting the theory of planned behavior to the theory of information, these theses fill in the issues of behavioral economics theory. The practical implication is a methodological approach of the model.
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Harm reduction services in the Czech republic and abroad.
TOVT, Šárka
Bachelor thesis on Harm reduction services in the Czech Republic and abroad theme is focused on methods to reduce the risk of drug addicts. It deals with the description of the various services offered in the Czech Republic, Great Britain, United States of America and the Russian Federation. In the thesis explains the concept of harm reduction, principles, strategies and attitudes. I deal with the concept of prevention and drugs that are inherent to components of harm reduction. The work is led by a theoretical order to compare services offering methods to reduce risk across the different countries. Describes various services such as needle and syringe exchange, testing for STDs , condom distribution and other ways to reduce risks in the drug scene. In the Czech Republic these services take place most often in areas of contact centers, where social workers caring for clients with drug addictions who are currently unable or unwilling to abstain or in their natural environment by the outreach services. In this work, I tried to take into account the findings of work in the KC Prevent , o.s. , KC Kotec, o.s. , Doléčovací zařízení Prevent , o.s. , Adiktologická poradna Prevent , o.s.
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Strucutre and disturbance regime of the natural spruce mountain forests in the Fagaras Mts. in Romania
Sýkora, Ondřej ; Svoboda, Miroslav (advisor) ; Janda, Pavel (referee)
There is a large natural disturbance in spruce stands at the present moment in many European countries. Therefore understanding of the long-term natural processes and the impact of disturbances on the structure have a key role in the management of spruce forests. For this purpose, we have studied the structure and the historical regime mountains, which is one of the best preserved forest ecosystems in the Europe. Between 2011 and 2013 years we have founded nearly 50 research spots in the four valleys where we collected data on the structure of the forest. For purposes of reconstruction of disturbances history samples from almost 3 500 individuals of Norway spruce (Picea Abies) were taken. Data were analyzed with dendrochronological methods and descriptive statistics. Partial synchronization of disturbances with the valleys and the subsequent rise in the regeneration was detected, which shows the influence of disturbances evoked by wind and then, probably, by the increasing population of bark beetles. We noticed the importance of the disturbances (weak - strong), which directly influences the structure and creates the mosaic diversity of vegetation. The history of the oldest areas goes back for 400 years, and for the youngest - for 100 years. The volume of the deadwood in the valleys was approximately 135 m3. Overall, on the investigated spots 1380 individuals of regeneration with dominating recovery of Norway spruce (Picea Abies) were recorded, with the proportion of 76 %.
Our results show that the disturbances are partially synchronized with the landscape level and also on the level of each valley, and have a major impact on the structure and dynamic of the forest. Natural disturbances are the main factor affecting the natural regeneration of spruce forests.
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Long-term changes of forest vegetation - the comparison of present species composition and biodiversity with the historical records
Vojík, Martin ; Boublík, Karel (advisor) ; Douda, Jan (referee)
The thesis presents the results of the research of the long term changes in semi-natural vegetation of lowland woodlands in the forest district Klínec (phytogeographical district Střední Povltaví, Central Bohemia, Czech Republic), which is located between the northeastern part of the Brdy Highlands (Hřebeny) and the Vltava River valley. Research of the long term changes over the past nearly 60 years was conducted by resampling vegetation on semi-permanent plots. Old relevés by V. Samek (1957), which were provided by the Czech National Phytosociological database, were used as reference data. Twenty-nine relevés were resampled, which were located using old data and GIS. The shift to shady plant communities (loss of heliophilous and expansion of shade-tolerant species) was found in the study area caused by higher canopy of tree and shrub layer due to the expansion of deciduous trees. Species richness (alpha diversity) was significantly declined. Homogenization of the vegetation was not significantly demonstrated in study area. Species of nutrient-rich habitats as well as alien and invasive species were expanded and fewer red list species of vascular plants was found. Vegetation change in the area was probably most affected by the change in forest management in lowland woodlands (decline of coppicing), eutrophication (deposition of nitrogen from the atmosphere, runoff from agricultural land) and the effect of forest animals especially wild boars.
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