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Analysis of active substances in honey
Jelénková, Zuzana ; Kubešová,, Jitka (referee) ; Márová, Ivana (advisor)
This diploma thesis was focused on biologically active compounds determination. 26 samples of honey, one sample of propolis and one sample of royal jelly were analyzed. Honey were harvested in year 2006 and 2007 and bought in retail chain, special shops and directly from bee-keeper. Samples were analyzed by titration, spectrofotometry, LC/MS and RP-HPLC methods. The study was focused on analysis of antioxidants. Followed groups of antioxidants were determined: flavonoids, catechins, carotenoids, vitamins E, C, A. Authenticity of quality was determined by hydroxymethylfurfural analysis. Average values of total antioxidant capacity ranged (12.75-137.49) mmol .100 g-1. Average values of total phenolic ranged (8.51-61.34) mg .100 g-1 and average values of total flavonoids ranged (0.75-6.04) mg .100 g-1. Honey samples contained (41.83-585.10) g .100 g-1 of rutin, (9.30-313.40) g .100 g-1 of myricetin, (6.5-171.90) g .100 g-1 of luteolin, (3.19-436.37) g .100 g-1 of quercetin, (2.10-242.66) g .100 g-1 of apigenin, (0.15-105.12) g .100 g-1 of caempferol and (0.07-17.52) mg .100 g-1 of naringenin. From group of catechins there were measured (5.98-310) g .100 g-1 of catechin, (17.77-486.29) g .100 g-1 of epicatechin, (0.18-64.90) g .100 g-1 of catechin gallate and (0.59-140.56) g .100 g-1 of epicatechin gallate. From lipophilic compounds the most abundant in honey samples was tocopherol, its value ranged (29.20-8531.17) g .100 g-1. Content of ascorbic acid ranged (0.65-4.65) mg .100 g-1. Content of hydroxymethyl.furfural. ranged (0.26-4.06) mg .100 g-1. By LC/MS method luteolin, naringenin, protocatechin acid, coffee acid and p-cumaric acid in honeydew were detected and, furthermore, kyanidin and pinocembrin in floral honey were found. Mono-floral honey contained biologically active compounds the most, imperceptibly less contained multi-floral honey and honeydew honey. Acacia honey contained the lowest amount of biologically active compounds.
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Possibility of determination of selected flavonoides
Smělá, Margita ; Vitoulová, Eva (referee) ; Vespalcová, Milena (advisor)
The theoretic part of the bachelor‘s thesis deals with description of selected flavonoids as apigenin, quercetin, luteolin, keampferol, rutin, myricetin and with options of their determinations. There were described typical properities and effects of several flavonoids at first. In the next part there are principles of methods, especially high-performance liquid chromatography and capillary electrophoresis. The biggest attention was made to literary survey of determination flavonoids coumpounds mentioned above, by high-performance liquid chromatography and capillary electroproresis. There were described the collection of plant material for extraction of flavonids in the practical part. The white and blue grapes were frozen by dry ice as soon as they were separated from a busch. Grapes were made in a nitrogenous atmosphere and lyophilizated after the frozen.
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Use of capillary electrophoresis to determine a selected group of flavonoids
Tran Xuan, Tiep ; Mravcová, Ludmila (referee) ; Řezáčová, Veronika (advisor)
In recent years, the use of natural medicinal properties of plants has again come to the forefront of interest of the public. Because of their therapeutic properties, these plants are commonly used in alternative treatments for minor ailments. This thesis deals with the determination of polyphenolic acids in extracts from aronia, echinacea, tetradenia and centella. One of the aims of the thesis was to compare the amount of polyphenolic acids in individual plants with their antioxidant properties. The theoretical part includes a general introduction to flavonoids, introduction to polyphenolic acids, introduction to the principles of capillary zone electrophoresis and a summary of selected foreign studies for the determination of flavonoids. An important chapter of the theoretical part is a description of individual plants with an explanation of their possible therapeutic use. The experimental part is devoted to the process of optimization of electrophoretic determination of selected polyphenolic acids and evaluation of their content. It was found that in the extracts six representatives of polyphenolic acids occur in minimal amounts, often below the limit of quantification or detection of the method.
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Use of rare oils in cosmetics
Pilipenco, Alina ; Szotkowski, Martin (referee) ; Němcová, Andrea (advisor)
The purpose of this bachelor thesis was to research rare oils. The oils from selected plants (poppy, cannabis, thistle) is characterized by the content of active phenolic compounds, fatty acid composition, antioxidant and antimicrobial effects. First part of the thesis is a literary research on a given topic, which contains the following parts: the universal chemical composition of vegetable oils, the characteristics and effects of selected oils and the ways of their obtaining for cosmetic purposes. The experimental part is focused primarily on the basic analysis of selected oil components and the preparation of the shower oil based on the obtained results. In conclusion are presented an overview of all the properties of selected oils, their practical use and assessment of their application in cosmetics.
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Účinky vybraných peptidů na jednobuněčnou řasu Chlamydomonas reinhardtii
Avdeeva, Olga
In the presented work, the modified novicidin peptides NVCAA and NVCHH were applied to the unicellular alga Chlamydomonas reinhardtii. The aim of the study was to determine the minimum inhibitory concentrations of the tested peptides on Escherichia coli bacteria with subsequent application on the unicellular algae Chlamydomonas reinhardtii. The assessment of the effect of the tested peptides on the algae was carried out using spectrophotometric analyses: chlorophyll A and chlorophyll B content, total flavonoid content, total antioxidant capacity and using the DPPH ASSAY method. Chlamydomonas reinhardtii molecular changes were determined by monitoring the amount of isolated RNA and the expression of APX1, APX2, CAT1, CAT2 genes using the Real-time PCR method. Statistically processed data showed that the application of NVCAA and NVCHH peptides induced considerable stress in the cilia.
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Vliv zpracování borůvek na obsah biologicky aktivních látek
Balaščáková, Viktória
This thesis deals with the influence of blueberry processing on the content of bioactive compounds. The aim of the study was to determine and compare the content of bioactive compounds in six types of storage and processing of blueberries. Spectrophotometric analysis was used to determine the content of polyphenols, flavonoids, total antioxidant capacity determined by the TEAC method, and total antioxidant capacity determined by the DPPH method in frozen, oven-dried, freeze-dried, stored at 6 °C, and poorly stored blueberries of the Brigitta variety. The highest content of flavonoids was found in the freeze-dried samples and the lowest content was found in the frozen samples. The highest content of antioxidant capacity determined by the TEAC method was found in the freeze-dried samples. The second highest content of antioxidant capacity by the TEAC method was found in the oven-dried samples. Stored samples in the freezer had the lowest antioxidant capacity content determined by the TEAC method. Samples that were oven-dried had the highest antioxidant properties against free radicals, as determined by the DPPH method. The second-highest content of antioxidant capacity by the DPPH method was found in the freeze-dried samples. Conversely, the lowest value of antioxidant capacity determined by the DPPH method was found in samples frozen at -80°C and -20°C. The difference in values between the freeze-dried and oven-dried samples was very small when determined by the DPPH method. The results indicate that the lyophilization process was identified in this study as the most suitable for preserving bioactive compounds in blueberries.
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Biologicky významné látky v bylinných čajích u čeledi hvězdnicovité
Stejskalová, Lenka
The importance of herbs and herbal teas is a frequently researched topic due to the content of biologically active substances. Plant material is a source of a large number of diverse components, which are proven to have a beneficial effect on the human organism. These substances are able to help in the prevention and possibly treatment of some human diseases. To fully understand the function of individual plants, it is necessary to know the content of individual groups of biologically active substances. The first part of this master's thesis named Biologically Important Substances in Herbal Teas of the Family Asteraceae escribes and defines herbal teas and organic farming. It also describes the Asteraceae family and focuses more specifically on selected species within this family, including marigold (Calendula officinalis), chamomile (Matricaria chamomilla L.), coltsfoot (Tussilago farfara L.) and coneflower (Echinacea purpurea). The consumption of herbal teas is currently high and still growing, therefore it is necessary to know the composition of the used plants. Representatives were chosen for their popularity and abundant use in the preparation of herbal teas. For each representative, there is a short botanical description and description of the contained substances. In the next chapter of the theoretical part, phenolic substances, their determination and effect on human health are presented. The group of flavonoids, which is a subgroup of phenolic substances, is described in more detail. The last section of the theoretical part explains the concepts of antioxidants, free radicals and methods of determining antioxidant activity. These groups were selected for measurement because they are substances showing effect on human health. In the practical part of this work, the total content of polyphenols, the total content of flavonoids and the total antioxidant capacity are determined in selected species. All these groups are determined spectrophotometrically. The essence of this work was to find out whether the content of these compounds in the same in samples from different productions. For each representative, one sample originating from organic farming (known as “BIO“) and one sample originating from conventional agriculture are examined. These two samples were statistically compared.
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Stanovení biologicky aktivních látek v čerstvých ovocných šťávách
Františová, Gabriela
Fruit is a valuable source of biologically active compounds. These compounds are often contained in minor amounts. A large proportion in fruit is made up of carbohydrates. In this work, the contents of vitamin C, polyphenols, flavonoids, glucose, fructose and sucrose in fresh fruit juices were determined. Aronia, strawberries, josta, raspberries, blackberries, white and blue grapes, white and red currants were obtained from a private garden, blueberries were collected in the wild. The vitamin C and carbohydrate concentrations were determined using HPLC. The total polyphenol and flavonoid contents were measured using spectrophotometry. Of the biologically active compounds, polyphenols were the most abundant in the fruit juices. The highest contents of polyphenols and flavonoids were detected in aronia (7905.81 ± 622.65 mg/l and 4714.82 ± 667.37 mg/l). Josta was the most significant source of vitamin C (721.90 ± 1.79 mg/l). Fructose in white grapes was the highest concentrated compound (93.81 ± 3.74 g/l). The highest glucose content was detected in aronia (83.95 ± 4.80 g/l) and white grapes (90.94 ± 3.48 g/l). Sucrose was detected in strawberries, gooseberries and raspberries.
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Secondary Metabolits of Bryophytes
Štěpán, Michal ; Soldán, Zdeněk (advisor) ; Skýbová, Jana (referee)
The bryophytes are a very old group of plants that are credited with being the first to make the transition to land. To make this land transition possible, plants needed to develop strategies to combat various external environmental factors. And these means, to effectively combat the struggle on land, are various secondary metabolites. It goes without saying that the development of various protective mechanisms did not end there. In the conditions in which mosses live, they need to fight against various fungi and bacteria. In the fight against these organisms, they also use various secondary metabolites, of course. Moss secondary metabolites are a very interesting and understudied field. In this work, information regarding secondary metabolites of bryophytes and their analysis as well as the possible uses of isolated secondary metabolites are included. The beginnings of secondary metabolite research are covered, from one of the first terpenes isolated, which was marchantin in Marchantia polymorpha, to present-day studies focusing on the discovery of new secondary metabolites directly in selected representatives of bryophytes and, of course, their applicability in human activities. It has been confirmed from various international publications that bryophytes produce specific secondary metabolites...
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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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