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Use of Waste Substrates to Production of Enriched Yeast Biomass
Starečková, Terezie ; Demnerová, Kateřina (referee) ; Vávrová, Milada (referee) ; doc.PharmDr.Petr Babula, Ph.D. (referee) ; Márová, Ivana (advisor)
Yeasts are like other organisms constantly exposed to environmental influences. Their survival depends on the skills to adapt to environmental changes, including the ability to use various alternative sources of nutrients. In presented PhD thesis carotenogenic yeast belonging to the genera Rhodotorula, Sporobolomyces and Cystofilobasidium were tested for ability to use of selected waste substrates, and also subjected to several types of exogenous stress effects and mutations in order to increase the production of microbial biomass enriched with specific metabolites. As alternative nutrient sources derived from waste substrates from agricultural and farm production apple peel, pulp, corn germ and more were tested. Yeasts were also exposed to osmotic, oxidative and combined stress (benefits of various concentrations of NaCl and H2O2 to the culture media), followed by metal ions of selenium and chromium in concentrations of 0.01 mM, 0.1 mM and 1 mM. The effect of mutagen methanesulfonic acid ethyl ester was tested too. In all experiments the adaptivity of cells, morphological changes, color pigments produced by the media while some important fungal metabolites production and changes in chromosomal DNA fragmentation were analyzed. In order to evaluate potential changes in the yeast genome after treatment with mutagen and stress factors methods for isolation of intact chromosomal DNA and DNA analysis by pulsed field gel electrophoresis was optimized. The amount of produced metabolites was mainly analyzed by RP-HPLC with UV/VIS and MS detection. The work has been shown that most strains are able to use waste substrates and produced selected target metabolites. Biomass, for example, in R. aurantiaca on apple fiber was about 7 g/l and in C. capitatum cultivated on modified whey reached to 9 g/l. Amount of produced carotenoids by R. aurantiaca cultivated on wheat germ and maize after enzymatic hydrolysis by F. solani was 1.01 mg/g and S. roseus on pasta 4.3 mg/g. The values of ergosterol synthesis in R. aurantiaca are on the apple shells around 4.8 mg/g, in S. roseus on pasta with the enzymatic hydrolysis of P. chrysosporium 8.9 mg/g. The best substrate for biomass production and induction of carotenoids are waste substartes containing a mixture of simple and complex carbohydrates enriched with the addition of nitrogen compounds. Potential cytotoxic effect of stress factors of low concentrations was demonstrated. Red yeast genome was able to distribute by optimized PFGE, the karyotype of tested yeasts contain 11 or more chromosomes with visible differences between yeast species and genera. During exchange internship the ability of recombinant yeast S. cerevisiae to convert xylose to xylitol, which would be achieved by increasing the production of bioethanol as alternative fuel sources was studied. It turned out that both ligninocellulose materials to bioethanol production, as well as various waste substrates for microbial synthesis of carotenoids would reduce costs for industrial production of yeast metabolites, as well as to reduce the negative burden on the environment.
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Automatic stress detection using non-EEG biological signals
Malina, Ondřej ; Kolářová, Jana (referee) ; Smíšek, Radovan (advisor)
This work deals with the problem of stress detection using non-EEG biosignals. The first part deals with the definition of stress and related concepts. Describes possible views of the phenomenon of stress, mentions possible causes of stress, as well as physiological and psychological manifestations of short and long-term effects of stress. In addition, this work deals with several different methods used to detect stress with non-EEG signals. For this purpose, a short search of articles dealing with this topic is available in this paper. The last chapter of this work describes the algorithm design using the c-mean fuzzy method for detecting stress values in data obtained form five different non-EEG signals.
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Production of pigments by yeasts
Gonová, Dominika ; Hlaváček, Viliam (referee) ; Němcová, Andrea (advisor)
Carotenoids are naturally occurring pigments synthesized by yeast, bacteria, filamentous fungi and plants. In recent years, the interest in the study of these pigments and their microbiological production is increasing mainly due to significant biological effects attributed to carotenoids. This work is conceived as comparative study of six carotenogenic yeasts: two strains of species Rhodotorula glutinis, Rhodotorula mucilaginosa, Sporobolomyces roseus, Sporobolomyces metaroseus a Sporobolomyces pararoseus. Their cultivation was carried out in various media where the oxidative stress was applied in the form of hydrogen peroxide and also waste material – egg pasta – was used as a nutrition source. All studied strains were able to use waste substrate as a source of nutrients, in case of the genus Sporobolomyces increasing production of metabolites was observed. Under the oxidative stress, the majority of the studied yeast showed overproduction of carotenoids and accompanying lipid substances. Sporobolomyces roseus CCY 19-6-4 was characterized by the highest production of carotenoids (1923.78 µg/g -carotene) at the egg pasta media, but on the other hand, it showed a significant decline in biomass. As potentially the best producer of biomass (9.85 g/l) and carotenoids (780.24 µg/g of -carotene), the yeast Rhodotorula glutinis CCY 20-2-26 was observed. Pulcherrimin, synthesized mainly by yeast but also by some spore-forming bacteria, also belongs among natural pigments. Recently, its antagonistic effect that was shown against several microorganisms has been intensively studied, as it seems to be very relevant in regard to biological control. The second part of the work deals with the regulation of pulcherrimin production and its antimicrobial activity. As the pigment-producing yeast strains were used Metschnikowia pulcherrima 145, Metschnikowia pulcherrima 147, Mestchnikowia pulcherrima 149, Metschnikowia andauensis 129, which were cultured on various media containing different concentrations of metal ions and hydrogen peroxide as exogenous stress. In the study of pulcherrimin antagonistic effect, gram-positive bacteria Lactobacillus sakei, gram-negative bacteria Escherichia coli, yeast Candida glabrata and filamentous fungi Phanrochaete chrysosporium were used as tested microorganisms. All studied yeasts were able to produce pulcherrimin, and therefore to show antagonist effect, only in media supplemented with iron, while the color intensity was proportional to the concentration of iron. Antimicrobial activity of pulcherrimin was not observed only against bacteria Escherichia coli.
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Automatic stress detection using non-EEG biological signals
Malina, Ondřej ; Kolářová, Jana (referee) ; Smíšek, Radovan (advisor)
This work deals with the problem of stress detection using non-EEG biosignals. The first part deals with the definition of stress and related concepts. Describes possible views of the phenomenon of stress, mentions possible causes of stress, as well as physiological and psychological manifestations of short and long-term effects of stress. In addition, this work deals with several different methods used to detect stress with non-EEG signals. For this purpose, a short search of articles dealing with this topic is available in this paper. The last chapter of this work describes the algorithm design using the c-mean fuzzy method for detecting stress values in data obtained form five different non-EEG signals.
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Production of pigments by yeasts
Gonová, Dominika ; Hlaváček, Viliam (referee) ; Němcová, Andrea (advisor)
Carotenoids are naturally occurring pigments synthesized by yeast, bacteria, filamentous fungi and plants. In recent years, the interest in the study of these pigments and their microbiological production is increasing mainly due to significant biological effects attributed to carotenoids. This work is conceived as comparative study of six carotenogenic yeasts: two strains of species Rhodotorula glutinis, Rhodotorula mucilaginosa, Sporobolomyces roseus, Sporobolomyces metaroseus a Sporobolomyces pararoseus. Their cultivation was carried out in various media where the oxidative stress was applied in the form of hydrogen peroxide and also waste material – egg pasta – was used as a nutrition source. All studied strains were able to use waste substrate as a source of nutrients, in case of the genus Sporobolomyces increasing production of metabolites was observed. Under the oxidative stress, the majority of the studied yeast showed overproduction of carotenoids and accompanying lipid substances. Sporobolomyces roseus CCY 19-6-4 was characterized by the highest production of carotenoids (1923.78 µg/g -carotene) at the egg pasta media, but on the other hand, it showed a significant decline in biomass. As potentially the best producer of biomass (9.85 g/l) and carotenoids (780.24 µg/g of -carotene), the yeast Rhodotorula glutinis CCY 20-2-26 was observed. Pulcherrimin, synthesized mainly by yeast but also by some spore-forming bacteria, also belongs among natural pigments. Recently, its antagonistic effect that was shown against several microorganisms has been intensively studied, as it seems to be very relevant in regard to biological control. The second part of the work deals with the regulation of pulcherrimin production and its antimicrobial activity. As the pigment-producing yeast strains were used Metschnikowia pulcherrima 145, Metschnikowia pulcherrima 147, Mestchnikowia pulcherrima 149, Metschnikowia andauensis 129, which were cultured on various media containing different concentrations of metal ions and hydrogen peroxide as exogenous stress. In the study of pulcherrimin antagonistic effect, gram-positive bacteria Lactobacillus sakei, gram-negative bacteria Escherichia coli, yeast Candida glabrata and filamentous fungi Phanrochaete chrysosporium were used as tested microorganisms. All studied yeasts were able to produce pulcherrimin, and therefore to show antagonist effect, only in media supplemented with iron, while the color intensity was proportional to the concentration of iron. Antimicrobial activity of pulcherrimin was not observed only against bacteria Escherichia coli.
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Use of Waste Substrates to Production of Enriched Yeast Biomass
Starečková, Terezie ; Demnerová, Kateřina (referee) ; Vávrová, Milada (referee) ; doc.PharmDr.Petr Babula, Ph.D. (referee) ; Márová, Ivana (advisor)
Yeasts are like other organisms constantly exposed to environmental influences. Their survival depends on the skills to adapt to environmental changes, including the ability to use various alternative sources of nutrients. In presented PhD thesis carotenogenic yeast belonging to the genera Rhodotorula, Sporobolomyces and Cystofilobasidium were tested for ability to use of selected waste substrates, and also subjected to several types of exogenous stress effects and mutations in order to increase the production of microbial biomass enriched with specific metabolites. As alternative nutrient sources derived from waste substrates from agricultural and farm production apple peel, pulp, corn germ and more were tested. Yeasts were also exposed to osmotic, oxidative and combined stress (benefits of various concentrations of NaCl and H2O2 to the culture media), followed by metal ions of selenium and chromium in concentrations of 0.01 mM, 0.1 mM and 1 mM. The effect of mutagen methanesulfonic acid ethyl ester was tested too. In all experiments the adaptivity of cells, morphological changes, color pigments produced by the media while some important fungal metabolites production and changes in chromosomal DNA fragmentation were analyzed. In order to evaluate potential changes in the yeast genome after treatment with mutagen and stress factors methods for isolation of intact chromosomal DNA and DNA analysis by pulsed field gel electrophoresis was optimized. The amount of produced metabolites was mainly analyzed by RP-HPLC with UV/VIS and MS detection. The work has been shown that most strains are able to use waste substrates and produced selected target metabolites. Biomass, for example, in R. aurantiaca on apple fiber was about 7 g/l and in C. capitatum cultivated on modified whey reached to 9 g/l. Amount of produced carotenoids by R. aurantiaca cultivated on wheat germ and maize after enzymatic hydrolysis by F. solani was 1.01 mg/g and S. roseus on pasta 4.3 mg/g. The values of ergosterol synthesis in R. aurantiaca are on the apple shells around 4.8 mg/g, in S. roseus on pasta with the enzymatic hydrolysis of P. chrysosporium 8.9 mg/g. The best substrate for biomass production and induction of carotenoids are waste substartes containing a mixture of simple and complex carbohydrates enriched with the addition of nitrogen compounds. Potential cytotoxic effect of stress factors of low concentrations was demonstrated. Red yeast genome was able to distribute by optimized PFGE, the karyotype of tested yeasts contain 11 or more chromosomes with visible differences between yeast species and genera. During exchange internship the ability of recombinant yeast S. cerevisiae to convert xylose to xylitol, which would be achieved by increasing the production of bioethanol as alternative fuel sources was studied. It turned out that both ligninocellulose materials to bioethanol production, as well as various waste substrates for microbial synthesis of carotenoids would reduce costs for industrial production of yeast metabolites, as well as to reduce the negative burden on the environment.
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The influence of stress on the duality of life and the work efficiency of workers in the helping professions
KOVÁŘÍKOVÁ, Lenka
This bachelor thesis deals with the Impact of stress on the quality of life and work performance of staff in helping professions. Currently, the challenge is the omnipresence of stress factors in day-to-day life and the impact of stress on quality of life and our health. The bachelor thesis you are holding in your hands is an attempt of a compact view of stress and its impact on quality of life. The paper is devoted to a harmful stress that can suppress potential, negatively affect work performance and health status, as well as positive stress, which can positively affect the workload and develop creativity and motivation. The theoretical part of the thesis is focused on working with specialised literature on the basis of which describes the characteristics of stress, effects on health and mental balance in both work and personal life. In addition, I pay attention to individual causes of stress, reactions of the organism, their solutions and the effect on the human body and spirit. Finally, the thesis is devoted to stressors and typical stressful situations that can occur in an environment where the social worker or a worker in social services takes care of clients with special needs. Aim of the thesis focuses on mapping the stress load of staff in selected professional groups and its influence on performance and satisfaction in life. The second objective of my thesis is to find which efficient protective mechanisms and methods selected professional groups use to overcome stress and to maintain a standard quality of life. Before the actual research initiation, two basic research questions were defined: 1) Stress experienced by staff in helping professions has no impact on quality of life. 2) Stress experienced by staff in helping professions has no impact on work performance. The research part was processed in the form of quantitative research through questionnaire survey using two standardised questionnaires with closed questions, supplemented by age, sex and work position of the respondents. The group of respondents was compiled from various age and gender groups, who are social workers or social service workers with professional focus on disabled persons and work with clients requiring special approach to organisations operating in the territory of České Budějovice. A medium-sized observation sample (53 and 72 respondents) was processed in the research investigation. The objective of this thesis was achieved and both initially introduced hypotheses: "Stress experienced by staff in helping professions has no impact on quality of life" and the hypotheses "Stress experienced by staff in helping professions has no impact on work" were confirmed and at the same time can be defined (on the basis of the research) a hypothesis that the majority of surveyed respondents in the helping professions is exposed to multiple sources of stress, nevertheless symptoms of stress are not present at high levels, although methods for coping with stress are not fully adequate. Furthermore, it may be (with regard to quality of life of the chosen group of respondents) also defined a hypothesis that men and women maintain a standard quality of life despite the stress load in the profession. In conclusion, a view could be taken that even though workers in social services and social workers in the helping professions are exposed to stress they are able to work with stress and have mastered mechanisms to help fight against stress and handle the burden which is caused by stress. Despite knowledge of the mechanisms in the fight against stress, it is necessary that the these workers shall continue educating themselves in future and learn to resist stress and be resilient against its negative effects as each respondent has some stress management reserves.
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