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Cereals - Active Substances, Biological Effects and Selected Applications in Food Industry
Lichnová, Andrea ; Tremlová, Bohuslava (referee) ; Vávrová, Milada (referee) ; Márová, Ivana (advisor)
The presented doctoral thesis is focused on the study of the biological effects of active compounds found in cereals, on the development of methods of analysis these effects, on the determination of the content of active substances and characterization of the relationship between composition and biological effects of cereals and cereal products. For the analysis several kinds of raw cereal samples (flakes, flour, germ, bran), flavored extruded cereal products and also samples of paddy and husked rice were chosen. To major types of analysed active compounds belong mainly phenolic compounds in the form of glycosides and aglycones, and also saccharides. Group parameters such as total polyphenols, flavonoids and total and reducing saccharides were determined spectrophotometrically, individual phenolics and saccharides were determined by high performance liquid chromatography (HPLC). TEAC, DPPH and CLAMS methods were used to determine the antioxidant activity. Indirect methods of determination of substances with antioxidant effect were used as well. Results of the total antioxidant activity were compared with values of antimutagenic/genotoxic activity obtained by several microbial test systems. Antimutagenic effect was expressed as a percentage of inhibition of effect of standard mutagen and could be considered as a potential preventive effect of cereals to DNA arising primarily by free radicals effect. The highest values of group and individual phenolics, antioxidant and antimutagenic activity were found in germs, bran, in buckwheat products and in coloured and raw rice. In flavoured cereal products addition of chocolate or fruit positively influences content of active phenolic substances as well as sugars, antixidant and antimutagenic activity. In a representative sample of Czech population, questionnairy study was performed to monitor interest in cereals and consumer preferences. The most of consumers consider cereals with chocolate flavour as less healthy than confirmed results of laboratory analyses. In this study some new food products were developed. Several types of model cereal products containing plant (fruit, vegetables) extracts were proposed. Extracts were added to cereals in freeze-dried and encapsulated form. The highest positive effect exhibited addition of local forrest fruit extract. Within preparation of encapsulated extracts several methods of preparing lipid or saccharides particles were also tested. The encapsulation efficiency of the methods and stability and size of particles were analysed. Optimal type of fortified cereal foods could be suggested based on the acquired results. Selected cereals were used as alternative carbon substrates (processed or raw) for the cultivation of microorganisms to produce enriched biomass usable in the feed industry. We can conclude that cereals in raw as well as processed form belong to universal foods and rich sources of biologically active substances. They can be processed by many ways. They can be used for direct consumption, as a part of new products and also undirectly as a substrate for feedstock.
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Application of Selected Methods for Oxidative Stress Analysis
Lízalová, Martina ; Tremlová, Bohuslava (referee) ; Beklová, Miroslava (referee) ; Vávrová, Milada (referee) ; Lojek, Antonín (advisor)
Chronic pancreatitis (CP) is a heterogeneous disease defined as chronic inflammatory changes of the pancreatic tissue caused by variety of aetiologies. Oxidative stress accompanying the inflammatory processes has been suggested as an important factor contributing to CP development. The aim of this study was to determine levels of lipid peroxidation products malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE), together with nitrites, the total antioxidant capacity, cytokines, biochemical and haematological parameters in the plasma of patients with CP and control subjects. Levels of MDA and 4-HNE were analyzed using high-performance liquid chromatography. The total antioxidant capacity of plasma against peroxyl radicals was evaluated using chemiluminescence determination. Nitrites were determined using Griess reaction. Cytokines - TNF-alfa; TNF RI; PDGF-AB; TGF-beta, together with myeloperoxidase and hyaluronan were determined using ELISA Kits. Biochemical and haematological parameters were measured by standard methods.
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Content of adaptogens in vegetable Schizandra chinensis
Kozáková, Soňa ; Tremlová, Bohuslava (referee) ; Kotlík, Josef (advisor)
This thesis deals with the content of adaptogens in vegetable Schizandra chinensis. The theoretical part deals with the plant Schisandra chinensis, its occurrence, characteristics, uses and cultivation. Location of plants Schisandra chinensis are classified according to Köppen climate classification and compared with the climate in the Czech Republic, due to possible prediction of growing plants in the country. Further are described adaptogens (bioactive substances) contained in this plant and to methods for their extraction and analysis. The experimental part of the thesis deals with the identification of schisandrin in the plant Schisandra chinensis grown in our conditions. The assessment was performed by ultra-performance liquid chromatography (UPLC), high-performance liquid chromatography (HPLC) and direct injection into tha mass spectrometry (MS). Schisandrin was successfully identified in all the samples.
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Cereals - Active Substances, Biological Effects and Selected Applications in Food Industry
Lichnová, Andrea ; Tremlová, Bohuslava (referee) ; Vávrová, Milada (referee) ; Márová, Ivana (advisor)
The presented doctoral thesis is focused on the study of the biological effects of active compounds found in cereals, on the development of methods of analysis these effects, on the determination of the content of active substances and characterization of the relationship between composition and biological effects of cereals and cereal products. For the analysis several kinds of raw cereal samples (flakes, flour, germ, bran), flavored extruded cereal products and also samples of paddy and husked rice were chosen. To major types of analysed active compounds belong mainly phenolic compounds in the form of glycosides and aglycones, and also saccharides. Group parameters such as total polyphenols, flavonoids and total and reducing saccharides were determined spectrophotometrically, individual phenolics and saccharides were determined by high performance liquid chromatography (HPLC). TEAC, DPPH and CLAMS methods were used to determine the antioxidant activity. Indirect methods of determination of substances with antioxidant effect were used as well. Results of the total antioxidant activity were compared with values of antimutagenic/genotoxic activity obtained by several microbial test systems. Antimutagenic effect was expressed as a percentage of inhibition of effect of standard mutagen and could be considered as a potential preventive effect of cereals to DNA arising primarily by free radicals effect. The highest values of group and individual phenolics, antioxidant and antimutagenic activity were found in germs, bran, in buckwheat products and in coloured and raw rice. In flavoured cereal products addition of chocolate or fruit positively influences content of active phenolic substances as well as sugars, antixidant and antimutagenic activity. In a representative sample of Czech population, questionnairy study was performed to monitor interest in cereals and consumer preferences. The most of consumers consider cereals with chocolate flavour as less healthy than confirmed results of laboratory analyses. In this study some new food products were developed. Several types of model cereal products containing plant (fruit, vegetables) extracts were proposed. Extracts were added to cereals in freeze-dried and encapsulated form. The highest positive effect exhibited addition of local forrest fruit extract. Within preparation of encapsulated extracts several methods of preparing lipid or saccharides particles were also tested. The encapsulation efficiency of the methods and stability and size of particles were analysed. Optimal type of fortified cereal foods could be suggested based on the acquired results. Selected cereals were used as alternative carbon substrates (processed or raw) for the cultivation of microorganisms to produce enriched biomass usable in the feed industry. We can conclude that cereals in raw as well as processed form belong to universal foods and rich sources of biologically active substances. They can be processed by many ways. They can be used for direct consumption, as a part of new products and also undirectly as a substrate for feedstock.
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Application of Selected Methods for Oxidative Stress Analysis
Lízalová, Martina ; Tremlová, Bohuslava (referee) ; Beklová, Miroslava (referee) ; Vávrová, Milada (referee) ; Lojek, Antonín (advisor)
Chronic pancreatitis (CP) is a heterogeneous disease defined as chronic inflammatory changes of the pancreatic tissue caused by variety of aetiologies. Oxidative stress accompanying the inflammatory processes has been suggested as an important factor contributing to CP development. The aim of this study was to determine levels of lipid peroxidation products malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE), together with nitrites, the total antioxidant capacity, cytokines, biochemical and haematological parameters in the plasma of patients with CP and control subjects. Levels of MDA and 4-HNE were analyzed using high-performance liquid chromatography. The total antioxidant capacity of plasma against peroxyl radicals was evaluated using chemiluminescence determination. Nitrites were determined using Griess reaction. Cytokines - TNF-alfa; TNF RI; PDGF-AB; TGF-beta, together with myeloperoxidase and hyaluronan were determined using ELISA Kits. Biochemical and haematological parameters were measured by standard methods.
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Content of adaptogens in vegetable Schizandra chinensis
Kozáková, Soňa ; Tremlová, Bohuslava (referee) ; Kotlík, Josef (advisor)
This thesis deals with the content of adaptogens in vegetable Schizandra chinensis. The theoretical part deals with the plant Schisandra chinensis, its occurrence, characteristics, uses and cultivation. Location of plants Schisandra chinensis are classified according to Köppen climate classification and compared with the climate in the Czech Republic, due to possible prediction of growing plants in the country. Further are described adaptogens (bioactive substances) contained in this plant and to methods for their extraction and analysis. The experimental part of the thesis deals with the identification of schisandrin in the plant Schisandra chinensis grown in our conditions. The assessment was performed by ultra-performance liquid chromatography (UPLC), high-performance liquid chromatography (HPLC) and direct injection into tha mass spectrometry (MS). Schisandrin was successfully identified in all the samples.
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