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Determination of nutritional values and antioxidant capacity of different edible roots
Ciffrová, Karolína ; Bendová, Agáta (referee) ; Němcová, Andrea (advisor)
This bachelor thesis deals with selected edible roots, their nutritional composition, antioxidant capacity and use in healthy eating. Eight selected edible roots were analyzed: type A, B and C potatoes, red potatoes, sweet potatoes, and purple potatoes were selected as representatives of potatoes. Jerusalem artichoke and cassava represent the other two root crops. The theoretical section of the thesis describes the basic characteristics of root crops, as well as the description and composition of the nutritional substances they contain, i.e. proteins, carbohydrates, fats, vitamins and antioxidant properties. The general characteristics of the methods used for analysis are also described here. The experimental part is based on specific analyses, procedures, results, chemicals and laboratory equipment used to determine the basic nutritional values and antioxidant capacity of these selected root vegetables. First, the total dry matter content was established to be about 23 % in the selected root crops. Higher dry matter content was determined for the cassava at 35 %. Crude protein content determined by the Kjeldahl method ranges from 6.5-9.9 %. The gravimetrically determined fiber in the given root crops was in the range of 0.27–0.91 %. The starch content is significantly higher in the cassava (46 %) than in other root crops. The inulin content was determined in sweet potatoes and Jerusalem artichokes instead of starch content; this value is significant for the Jerusalem artichoke (258.58 g/kg). Fat content in grams per 100 grams of dry matter was determined by Soxhlet extraction. Significant fat content was determined for sweet potatoes (12.6 g/100 g). From the extracted fats, the fatty acid profile was determined for individual root vegetables, such as the content of saturated (SFA), monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA). Total and reducing carbohydrates, determined by the spectrophotometric method, were measured separately in the peel and pulp of the root crops. Antioxidant capacity was determined using antioxidant activity values, polyphenol and flavonoid concentrations. Of the vitamins, vitamin C was determined, vitamin E only in type B, C and purple potatoes. For sweet potatoes, beta-carotene was determined to be 540.56 g/g. The measured and calculated results are plotted in graphs. Finally, there is a discussion of the conclusions of the individual methods.
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Recipe of a food supplement based on bioactive substances isolated from Prunus spinosa
Červinková, Zuzana ; Hudečková, Helena (referee) ; Kovalčík, Adriána (advisor)
Blackthorn fruits (Prunus spinosa) are small blue-purple drupes containing a range of bioactive substances that give them diverse biological effects. They are traditionally used not only in folk medicine, as they are attributed with many preventive and therapeutic effects. The presented master´s thesis deals with the preparation and characterization of an ethanol extract and dietary supplements based on bioactive substances isolated from the fruits of blackthorn. The ethanol extract was prepared by maceration fresh Prunus spinosa fruits in 40% alcohol. The extract was analyzed for the polyphenols (2111.39±11.32 mg GAE/l), flavonoids (903.89±5.08 mg CAE/l) and anthocyanins (165.24±0.38 mg CGE/l) content, antioxidant (11.99±0.40 mmol TE/l) and antimicrobial activity, phenolic compounds profile and sugars profile. The ethanolic extract exhibited antibacterial effect against the gram-positive bacterium Micrococcus luteus and gram-negative bacterium Escherichia coli but was not effective against the yeast Candida glabrata. After gentle concentration on a vacuum evaporator, the extract was used to prepare a dietary supplement. Two types of dietary supplements were prepared, namely gelatine candies with blackthorn fruit extract and gelatine capsules filled with lyophilized fruit powder. The nutritional profile of these products, content of bioactive substances (i.e. total polyphenols, flavonoids, and anthocyanins), phenolic compound profile and antioxidant activity were characterized. Additionally, the release of polyphenols was monitored during a simulated in vitro digestion. The gelatine candies with different extract concentrations (5, 10, 15 and 20 %) were subjected to sensory evaluation, where the aim was to optimize the addition of the extract to the gelatine matrix. According to the preferences of the evaluators, the sample with 15 % extract was rated as the best in terms of overall taste. In the ranking test, this sample was ranked second, behind the sample with 5 % extract, which, on the other hand, received a worse sensory profile rating. The thesis also included monitoring the effect of freezing, lyophilization, and drying on the bioactive compounds content (i.e. total polyphenols, flavonoids, anthocyanins) and antioxidant activity of Prunus spinosa fruits. The highest contents of total polyphenols (57.49±0.33 mg GAE/g DW), flavonoids (45.75±0.12 mg CAE/g DW) and anthocyanins (6.41±0.19 mg CGE/g DW) were quantified in lyophilized fruits, but the highest antioxidant activity (281.72±0.70 mol TE/g DW) was observed in frozen fruits. A statistically significant moderately strong positive correlation (0.641) of antioxidant activity and total flavonoids was observed for the analyzed samples. The results of the thesis showed a great potential for the use of blackthorn berries in the nutraceutical industry, where they can contribute as active additives to increasing both the bioactive and nutritional quality of dietary supplements.
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Obsahové látky jedlých květů a jejich antioxidační aktivita
Tvrzníková, Eliška
This diploma thesis deals with phytochemicals with antioxidant effect in edible flowers. In the literary section are described edible flowers, antioxidants and substances harmful to human health. In the selected assortment is described the morphology of the flower, the origin, the distribution, the occurrence, the demands, the use and the multiplication according to whether they are species growing in the wild or cultivated species are described. In the practical part, flowers were harvested from March to May 2017 and their content was determined - vitamin C, flavonoids, phenols, saponins, antioxidants. This thesis confirmed that phenolic substances are primarily responsible for the antioxidant capacity. The highest antioxidant capacity along with phenolic substances was in the flowers of Bergenia ciliata.
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Stanovení flavonoidních látek ve vybraných druzích léčivých rostlin používaných v potravinářství
Bačová, Romana
In plant and food research the functional significance of herbs, spices and other plants, including their components is very popular topic. Plant material contains many components that are beneficial to human health by reducing the risk of chronic degenerative diseases. It is necessary to define the individual substances to understand and explain their biological effects. The first part of thesis describes the selected plants (elderberry, nettle, marigold, milk thistle, sea buckthorn, sage, purple coneflower and thyme) and also describes their medicinal properties and uses. The second part of thesis deals with phenolic and flavonoid substances. In the third (experimental) part, of thesis there were qualitatively and quantitatively determined flavonoid compounds in selected plant species. For identification the technique combining liquid chromatography and mass spectrometry - HPLC/MS was used. Extraction was carried out by vortexing and Soxhlet method, using two different concentrations of metanol. These metods were then statistically compared.
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Analytical approaches to study group interactions of azole pesticides with important biological active compounds
Kovač, Ishak ; Jaklová Dytrtová, Jana (advisor) ; Száková, Jiřina (referee) ; Navrátil, Tomáš (referee)
This dissertation presents a developed capillary electrophoresis method for analysing residues of triazole fungicides (TAF) from real samples ("Sweet cherry" tomato - Solanum lycopersicum L) and shows its potential application in environmental analysis. The developed method was validated in-house and characterised by a relatively short analysis time and low cost with sufficient LOD and LOQ. As an additional part of this dissertation, which rose from the tomato plants' treatment with TAF, we studied the impact of triazole fungicides on plant development and their impact on biologically active compounds. Determination of TAF residues from tomato peel carried out with capillary electrophoresis. Capillary electrophoresis is a versatile technique with minute amounts of sample required, with high efficiency in separating small molecules, such as selected TAF. The developed method, cyclodextrin-modified micellar electrokinetic chromatography, accomplished a baseline separation of the TAF mixture from tomato peel. The optimal conditions for separation were in the background electrolyte comprised of phosphoric acid and Tris (100 mM concentration, respectively), 20% v/v methanol, with apparent p[H+ ] 4.8. The constituents of the mixed micellar pseudo-stationary phase were ionic detergent sodium dodecyl...
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Bioactive compounds in green spices
ARNOŠTOVÁ, Lucie
The bachelor thesis focuses on the determination of the total content of phenolic compounds, individual majority phenolic compounds and vitamin C, contained in sweet basil (Ocimum basilicum), coriander (Coriandrum sativum), dill (Anethum graveolens) and lovage (Levisticum officinale). Firstly, the total content of phenolic compounds was determined by spectrophotometric analysis using Folin Ciocalteau agent in extracts from fresh and dried herb samples. Afterwards, particular representatives of phenolic compounds in the lyophilized material were identified by high-performance liquid chromatography (HPLC). Then the content of vitamin C in fresh samples from all selected plants was measured using high-performance liquid chromatography (HPLC). The highest concentration of phenolic compounds was discovered in lovage. The highest content of particular phenolic substances, quercetin and kaempferol, was also proved in lovage.
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The content of selected biologically active substances in wild plants traditionally used as vegetables
ŠUSTEROVÁ, Simona
A balanced diet should contain, in addition to essential nutrients, enough minority biologically active substances, such as essential vitamins and minerals. This group of substances include, for example, plant polyphenols, which act as effective antioxidants. A diet rich in natural antioxidant substances contributes to the prevention of serious civilization diseases, especially heart and blood vessels. People have always tried to enrich their diet with the resources of the biologically active substances. Particularly in spring, when stored foods lost their nutritional value, several wild plants came in. These have traditionally been used as a source of vitamins and other necessary substances. In our regions, they are traditionally a young nettle, but also some members of the family of crucifers. The aim of the bachelor thesis will be to select a set of suitable wild growing plants, to take samples for analysis and to determine the content of selected biologically active substances. A liquid chromatographic technique will be used to analyze the selected biologically active polyphenols contained in the plant material. It is a modern separation analytical technique, with which selected biologically active compounds are determined with high reliability.
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Biologicky aktivní látky v netradiční listové zelenině.
FRIEDBERGEROVÁ, Markéta
Flavonoids are now increasingly coming to the forefront of interest not only from the scientific community but also of the public. They were found to be very beneficial in the field of prevention of cardiovascular or cancer diseases. In addition, they have proven to have antioxidant, anti-allergic or anti-inflammatory effects. In this bachelor 's thesis, the contents of substances, namely quercetin, kaempferol, morin, myricetin, apigenin and luteolin, were investigated using HPLC method. Lyophilized material of four varieties of Asian leafy vegetable from the cruciferous family was selected for analysis: Namenia, Sagami, Golden Lion and Tatsoi. All samples were grown in spring and autumn sowing period. Only two of the monitored aglycones, quercetin and kaempferol, were determined. The highest content of total quercetin was registered in the autumn sowing period of Namenia 1360 mg/kg of dry matter, the content of total kaempferol 1300 mg/kg of dry matter in the Golden Lion variety, also in autumn sowing period. After conversion to fresh mass, the highest concentrations of both aglycones were measured in Namenia during autumn sowing period. The amount of quercetin was determined to be 157 mg/kg of fresh weight, while the kaempferol content was 114 mg/kg of fresh weight.
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Evaluation of flavonoids content in various species of Bergenia genus
Marková, Almíra ; Tůmová, Lenka (advisor) ; Karlíčková, Jana (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmacognosy and Pharmaceutical Botany Author: Almíra Marková Supervisor: Assoc. Prof. PharmDr. Lenka Tůmová, CSc. Title of diploma thesis: Evaluation of flavonoids content in various species of Bergenia genus Originally an Asian genus Bergenia from the family Saxifragaceae includes 32 species described so far and many hybrids that were created by crossing them. The leaves and rhizomes of bergenia used widely in folk medicine of China, India, Mongolia, and Russia are rich in a wide range of chemical constituents. The most important secondary metabolites of this plant are tannins, arbutin, bergenin, but also flavonoids. The drug is valued for its litholytic, antioxidant, anti-inflammatory, antipyretic, or antitussive properties. This work aimed to determine flavonoid content in red and green leaves of Bergenia crassifolia (L.) Fritsch, Bergenia ciliata (Haw.) Sternb. and Bergenia x ornata Guill. and their comparison with each other depending on the harvest period and climatic conditions. The samples were obtained from the botanical garden of the Faculty of Horticulture of Mendel University in Lednice. Flavonoid content was determined spectrophotometrically. The highest flavonoid content was measured in B. ciliata (1.1829 ±...
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