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Study of the effect of microbial degradation of lignin on its molecular weight
Fialová, Tereza ; Hudečková, Helena (referee) ; Kovalčík, Adriána (advisor)
This diploma thesis deals with the microbial degradation of lignin using wood-degrading fungi Fomitopsis pinicola and Lenzites betulina. In the first phase of the experimental part, media screening was carried out, the aim of which was to select the best media for fungal growth and production of ligninolytic enzymes. Based on the determination of activity, in the next step, the conditions for their production were optimized in selected media. As part of these experiments, the optimal concentration of lignin and glucose was selected for subsequent cultivations. Commercially available lignin was used as substrate. Based on the results of measured enzyme activities, Lenzites betulina was selected as the better producer. The most produced enzyme of this fungus was laccase, followed by manganese-dependent peroxidase and the least lignin peroxidase. Further experiments were performed only with L. betulina. In the next part of the experiment, lignin was characterized, and its properties compared before and after microbial degradation. Its molecular weight was determined by SEC-MALS and the change in structure by FTIR. The molecular weight of lignin decreased after cultivation and a change in its structure was also noted. The results show that the microbial degradation of lignin was successful.
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Use of some fractions of technical hemp in cosmetics
Gregarová, Lenka ; Hudečková, Helena (referee) ; Márová, Ivana (advisor)
Cannabis sativa is a versatile herb which is known for several thousand years and contains a variety of active substances. This thesis is focused on the use of some extracts of hem in cosmetics, specifically in hair cosmetics. The first part focuses on the Cannabis sativa, introducing the active contained substances and the overall processing of the plant. In the second part were experimentally determined the active substances in five extracts from different varieties, that were supplied from industry. Extracts were compared based on the extraction yield of antioxidants, chlorophylls, phenolic compounds, flavonoids and cannabinoids. Subsequently, a hair shampoo was prepared with the addition of hemp extracts and hemp hydrolysate. Lastly, the inhibitory effect against microorganisms was monitored for extracts and shampoos finally. Beneficial biologically active substances were detected in hemp extracts, wherein higher levels were measured in ethanol extracts. The extracts were also able to inhibit the growth of certain microorganisms. Satisfactory results on hair were observed with the prepared shampoo.
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UTILIZATION OF FOOD PROCESSING WASTE FOR LACTIC ACID AND ETHANOL PRODUCTION
Hudečková, Helena ; Kráčmar, Stanislav (referee) ; Buňka, František (referee) ; Márová, Ivana (advisor)
The doctoral thesis is focused on the microbial production of lactic acid and ethanol using food processing waste as substrate. Coffee processing waste (spent coffee grounds), wine production waste (grape pomace) and orange processing waste (orange peel) were chosen as substrates for experiments. The theoretical part is dedicated to summarizing current knowledge about waste from food production and possibilities of its processing. It also deals with selected metabolites (lactic acid, ethanol) to which these wastes can be used. Part of the experiments was focused on the characterization and optimization of hydrolysis to maximize the amount of fermentable saccharides. Different combinations of chemical, physical and enzymatic hydrolysis of selected substrates have been tested. Subsequently, a suitable strain for lactic acid and ethanol production was searched for. In the case of lactic acid production, 7 bacterial strains were selected (Lactobacillus casei CCM 4798, Bacillus coagulans CCM 2013, Bacillus coagulans CCM 2658, Lactobacillus rhamnosus CCM 1825T, Lactobacillus delbruckii subsp. bulgaricus CCM 7190, Lactobacillus plantarum CCM 7039T, Streptococcus thermophilus CCM 4757). These strains were first cultivated on the synthetic media containing different kind of saccharides. Afterward, the cultivation on the waste biomass hydrolysates were tested. In the case of ethanol production, 2 yeast strains kmeny (S. cerevisiae CNCTC 6646 a S. cerevisiae CNCTC 6651) were cultivated on hydrolysates of individual waste substrates. Subsequently, the experiments focused on the production of lactic acid and ethanol on hydrolysates of waste biomass in bioreactor were done. The last part of this doctoral thesis deals with the microaerobic pretreatment of lignocellulosic biomass to increase the production of organic acids during the acetogenic phase of anaerobic digestion.
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Production of organic acids by fibrous microscopic fungi and utilization of their biomass for removal of risk elements
Juglová, Zuzana ; Hudečková, Helena (referee) ; Urík,, Martin (advisor)
The aim of this bachelor thesis was to determine the most advantageous method for production of organic acids by microscopic flamentous fungus Aspergillus niger and to evaluate mercury bioaccumulation efficiency on collected fungal biomass. The theoretical part focuses primarily on utilization, metabolism and production on individual organic acids. This is followed by section focused on the toxicity of mercury and the principles of bioaccumulation of heavy metals in biomass. The experimental part focuses mainly on the optimization of cultivation, determination of content of produced organic acids, depending on the type of cultivation. Second point of practicle part is evaluating of mercury bioaccumulation depending on the initial concentration of mercury in solution. In overall comparison, the best type of cultivation is dynamic. Higher biomass yeild resulted in higher production of organic acids. The higher biomass synthesis is also beneficial for bioaccumulation of mercury.
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Encapsulation of probiotics for use in nutritional products for children
Šmídová, Veronika ; Hudečková, Helena (referee) ; Skoumalová, Petra (advisor)
This bachelor thesis is focused on optimization and development of probiotic food supplement with attractive look and active ingredient, like prebiotic or “superfood”, which are there for afford useful substances for organism. In the theoretical part is focused on probiotics and its encapsulation, also on prebiotics, which are used for work and screening probiotics food supplements in our market. The practical part is focused on optimization of composition of new probiotic food supplement, polysaccharide particles in the shape of a teddy bear were prepared. At first, the basic composition was optimized, as the best alginate-agar particles were determined. Addition of nutritionally valuable ingredients was also optimized. Particles with inulin, acerola, chia fiber, yacon syrup, chlorella and spirulina were prepared. Another part of this work was focused on the determination of the viability of probiotic bacteria Lactobacillus acidophilus and Bifidobacterium breve in various forms and after exposed to model digestion. The highest viability of the cells was measured after encapsulation of lyophilized cells into a polysaccharide particle. Prepared particles were finally subjected to a sensory analysis.
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Analysis and characterization of beta-glucans from some natural sources
Vít, Radek ; Hudečková, Helena (referee) ; Márová, Ivana (advisor)
The aim of the bachelor thesis is to test and characterize commercially available products with declared -glucans content. The theoretical part describes -glucans, their possible sources, properties and utilization. Further, the theoretical part is focused on methods for determination of -glucan content. Saccharomyces cerevisiae yeast and oyster mushroom fungus are available as commercial sources of -glucans. Next individual groups of the active substances and principles of the methods used for their characterization are described too. In experimental part of this work the extracts from five commercially available sources of -glucans were prepared and characterized. Antioxidant activity, total polyphenols, proteins and carbohydrates were determined. For selected products, the content of vitamin C using HPLC and the lipid content using GC-FID were determine as well. An enzymatic method was used to determine the -glucan content. Two samples of the highest antioxidant activity were then subjected to antimicrobial and MTT tests.
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The trends of spending leisure time in Náchodsko region (a comparative study in the rural area)
Kozáková, Helena ; Hudečková, Helena (advisor) ; Tomáš, Tomáš (referee)
Free time in today's life is becoming more and more important. The development of modern society and specialization of labor market today divides more obviously time for responsibilities and pastime. Leisure time is a very individual matter and its form is dependent on many aspects. Age and the size of the place of residence belong to those aspects that influence spending our free time. The relation between them became the core topic of this thesis. The practical part is based on my own research in three urban areas of different size in Nachod district. The research analyses the offer of free time activities as well as the attitude of the inhabitants in relation to their age and the size of town. The core task of this practical part was to look for any causal links. Deeper analysis shows that there is a certain coherence between the age of inhabitants, the size of their town and the style of spending leisure time, nevertheless this influence is not very significant. It is above all a very individual matter.
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Leisure time in small communities in Prague suburban area
Šubová, Alžbeta ; Hudečková, Helena (advisor) ; Kučerová, Eva (referee)
The thesis is focused on spending free time of inhabitants from two small villages in Prague sururban area and if there is any other option how to improve efficiency of spending free time of local inhabitants. The theoretical part concerns free time: its definiton, history, functions, factors which influence spending of free time. Essay gives information about two surveyved willages and its local options of free time activities.
The practical part used questionnaires and interviews which are described at the end of this thesis.
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Community activities (tradition and status quo) in small localities
Hatka, Tomáš ; Hudečková, Helena (advisor) ; Tomáš, Tomáš (referee)
The subject of this thesis is the sociocultural role of associations in small localities, which are villages and small towns. Through two selected interest activities typical for small localities and organized on the basis of associations / clubs, soccer clubs and volunteer fire, are explored traditions in selected municipalities and scope of current community activities. Importance is attached to social relations acting both within societies and among them. The theoretical basis is for them the concept of Ferdinand Tonnies Gemeinschaft und Gesellschaft, which indicating two types of social relations based on a distinction between two kinds of human will. Qualitative research focused on the perception of traditions, current status, mission and needs for the future with regard to the development activities carried out by three generations of representatives of these associations shows generational differences in perceptions of community activities. Through systematic registration of current needs with regard to the future development of community activities outlines this thesis opportunities for mutual cooperation, leading not only benefit the organizations themselves, but also for the location in which these associations are.
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Leisure time of young generation reflecting its function of prevention in the Rychnovsko region
Bílek, Radek ; Hudečková, Helena (advisor) ; Tomáš, Tomáš (referee)
This dissertation focuses on free time as a new phenomenon in the industrially advanced society. The goal of this paper is firstly to map how the monitored group of children and youth from Rychnov nad Kněžnou and surrounding villages spend their free time and secondly how the above mentioned group comprehends the preventive function of free time. After the theoretical part which is focused on sociology of leisure, leisure education, and rural and urban area, there is an empirical part containing secondary and primary research (performed in form of questioning) with special focus on offering free time activities. The research found out that both groups of pupils (from urban as well as from the rural area) perceive the free time, possibilities of spending it, and their wishes for better spending the free time in similar way. Although the offer of free time activities in the rural area is significantly more limited compared to the free time activities offered in the urban area, the pupils living in the rural area are surprisingly satisfied with the offer. This limited offer is often accompanied with more common feeling of boredom which could grow into being dangerous; in view of preventive function of free time this fact is not insignificant.
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