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Study of antimicrobial substances of ginger
Ciburová, Alena ; Skoumalová, Petra (referee) ; Veselá, Mária (advisor)
For thousands of years ginger rhizomes are used in traditional Chinese medicine. Because of his significant pungent flavour is commonly used in foods and beverages all over the world. Nowadays many of the beneficial pharmacological positive effects of ginger rhizomes are identified. Their occurrence is due to the high concentration of bioactive compounds. This thesis is focused on analysing of occurrence of bioactive compounds such as polyphenols and flavonoids and their influence on antioxidation and antimicrobial properties of samples of fresh and dried ginger. The results show that for extraction of bioactive compounds in different ginger samples is more suitable to use different types of extraction solvents. The highest antioxidation activity was measured for macerate of 100% bio ginger tea from Sonnentor company in 96% ethanol. Antimicrobial properties were showed only for 100% bio ginger tea against gram-positive bacteria Microccocus luteus.
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Study of the antioxidative potential of selected fruit marcs
Havlíčková, Barbora ; Zemanová, Jana (referee) ; Vespalcová, Milena (advisor)
Subject of this bachelor thesis was antioxidant activity of selected kind of fruits. Among selected kinds were the marc of red and white grapes, moldings from red elderberry and aronia. Two species of made capsules from marcs of white grapes and aronia were also subjected to analysis. Results of this bachelor thesis are summarized to four chapters. The first chapter compares the water content of drying at 40 ° C and 105 ° C. In the second chapter, the results of extraction in different proportions of solvent mixture ethanol - water and results of extraction in prepared artificial gastric juice are discussed. As a result, the water – ethanol mixture was a more effective solvent than artificial gastric juice. The third chapter deals with the results and discussion of the determination of the total content of phenolic substances. For the solvent mixture, the largest amount of polyphenols in the red vine marc was determined to be 43,56 mg.g-1, while in gastric juice the largest content in the elderberry was determined to be 11,89 mg.g-1. Capsules were also extracted in gastric juice, and 2,53 mg.g-1 was found in aronia tablets, while 5,93 mg.g-1 in white grape tablets. The last chapter compares the results of TAA measurements using the TEAC and EPR methods. The EPR method was more suitable for much diluted solutions than the TEAC method. The results of this work show that there is a large number of polyphenols and other antioxidants in the moldings that affect the overall antioxidant activity. Marcs have great potential for use as natural dyes or can be used to make a food supplement.
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Uses of active compounds from honey in cosmetic products
Balášová, Patricie ; Langová, Denisa (referee) ; Skoumalová, Petra (advisor)
The bachelor thesis was focused on the preparation and characterization of extracts and liposomes with active substances from chosen types of honey with the aim to apply these extracts to the cosmetic products. The extraction of active substances from chosen material was optimized during the work. As the most suitable organic solvent for extraction was chosen diethyl ether. All the extracts were tested on the content of total polyphenols, sugars and antioxidation activity. The final samples were also tested on the content of flavonoids. Extracts were encapsulated to the liposomes, which were tested especially for their antioxidation activity, size and stability. Then, extracts and liposome particles were applied to the cosmetic products. Cosmetic creams and gels were prepared and tested for antioxidation activity and antimicrobial activity against the strains Serattia marcescens and Micrococcus luteus. Antimicrobial activity of gels was proved especially against the strain of grampositive bacterias – Micrococcus luteus. From this point of view another one testing strain was chosen – Propionibacterium acnes. Finally, the chosen liposomes were tested for their contact with human cells, immortalized keratinocytes HaCat. No cytotoxic effect was observed and tested materials can be applied to cosmetics against acne.
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Evaluation of beetroot qualitative parameters
MIKEŠOVÁ, Mariana
The thesis si lead to evaluate volume of betalain pigments and analyze antio-xidant activity in selected species of beetroot. The thesis is sorted to several chapters . The first chapter discusses about history, individual species of beetroot and general properties. There are information about antioxidant activity and pigments, which is occure in beetroot in the next. The second part of the thesis is focused on analyze the betalain pigments and evaluate antioxidant activity. It leads to resume, that beetroots with red-violet color are more rich about antioxidant substances. Examination of the individual colours for the selected varieties revealed that the 'Redshine' varieties were mainly rich in beta-cyans and betaxantines. "Monorubra." The highest content of these dyes are the varieties which have the colour of the pulp red to dofia-lova. Their values were significantly higher than those of the 'Boldor F1' variety, which would have been expected to have a higher betaxantine content than the red-coloured varieties
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Evaluation of cultivar effect on content of betalain pigments in beetroot
AUEROVÁ, Anežka
The thesis si lead to evaluate volume of betalain dyes and analyze antioxidant activity in selected species of beetroot. The thesis is sorted to several chapters . The first chapter discusses about history, individual species of beetroot and general properties. There are information about antioxidant activity and dyes, which is occure in beetroot in the next. The second part of the thesis is focused on analyze the betalain dyes and evaluate antioxidant activity. It leads to resume, that beetroots with red-violet color are more rich about antioxidant substances. It is more healthier than others.
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Study of the antioxidative potential of selected fruit marcs
Havlíčková, Barbora ; Zemanová, Jana (referee) ; Vespalcová, Milena (advisor)
Subject of this bachelor thesis was antioxidant activity of selected kind of fruits. Among selected kinds were the marc of red and white grapes, moldings from red elderberry and aronia. Two species of made capsules from marcs of white grapes and aronia were also subjected to analysis. Results of this bachelor thesis are summarized to four chapters. The first chapter compares the water content of drying at 40 ° C and 105 ° C. In the second chapter, the results of extraction in different proportions of solvent mixture ethanol - water and results of extraction in prepared artificial gastric juice are discussed. As a result, the water – ethanol mixture was a more effective solvent than artificial gastric juice. The third chapter deals with the results and discussion of the determination of the total content of phenolic substances. For the solvent mixture, the largest amount of polyphenols in the red vine marc was determined to be 43,56 mg.g-1, while in gastric juice the largest content in the elderberry was determined to be 11,89 mg.g-1. Capsules were also extracted in gastric juice, and 2,53 mg.g-1 was found in aronia tablets, while 5,93 mg.g-1 in white grape tablets. The last chapter compares the results of TAA measurements using the TEAC and EPR methods. The EPR method was more suitable for much diluted solutions than the TEAC method. The results of this work show that there is a large number of polyphenols and other antioxidants in the moldings that affect the overall antioxidant activity. Marcs have great potential for use as natural dyes or can be used to make a food supplement.
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Study of antimicrobial substances of ginger
Ciburová, Alena ; Skoumalová, Petra (referee) ; Veselá, Mária (advisor)
For thousands of years ginger rhizomes are used in traditional Chinese medicine. Because of his significant pungent flavour is commonly used in foods and beverages all over the world. Nowadays many of the beneficial pharmacological positive effects of ginger rhizomes are identified. Their occurrence is due to the high concentration of bioactive compounds. This thesis is focused on analysing of occurrence of bioactive compounds such as polyphenols and flavonoids and their influence on antioxidation and antimicrobial properties of samples of fresh and dried ginger. The results show that for extraction of bioactive compounds in different ginger samples is more suitable to use different types of extraction solvents. The highest antioxidation activity was measured for macerate of 100% bio ginger tea from Sonnentor company in 96% ethanol. Antimicrobial properties were showed only for 100% bio ginger tea against gram-positive bacteria Microccocus luteus.
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Uses of active compounds from honey in cosmetic products
Balášová, Patricie ; Langová, Denisa (referee) ; Skoumalová, Petra (advisor)
The bachelor thesis was focused on the preparation and characterization of extracts and liposomes with active substances from chosen types of honey with the aim to apply these extracts to the cosmetic products. The extraction of active substances from chosen material was optimized during the work. As the most suitable organic solvent for extraction was chosen diethyl ether. All the extracts were tested on the content of total polyphenols, sugars and antioxidation activity. The final samples were also tested on the content of flavonoids. Extracts were encapsulated to the liposomes, which were tested especially for their antioxidation activity, size and stability. Then, extracts and liposome particles were applied to the cosmetic products. Cosmetic creams and gels were prepared and tested for antioxidation activity and antimicrobial activity against the strains Serattia marcescens and Micrococcus luteus. Antimicrobial activity of gels was proved especially against the strain of grampositive bacterias – Micrococcus luteus. From this point of view another one testing strain was chosen – Propionibacterium acnes. Finally, the chosen liposomes were tested for their contact with human cells, immortalized keratinocytes HaCat. No cytotoxic effect was observed and tested materials can be applied to cosmetics against acne.
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Complexes of iron(II) salts and flavonoids
Schröpferová, Tereza ; Volný, Michael (referee) ; Roithová, Jana (advisor)
This work is devoted to a study of the interaction between iron(II) ions and flavonoids (epicatechin, catechin, quercetin) by means of mass spectrometry and electrospray ionization. First, a measurement with model molecules (pyrocatechol, resorcinol, 3-hydroxy-2-methyl-4- pyrone) has been performed in order to find how iron(II) intereacts with the OH groups on the hydrocarbon rings. It has been found that Fe2+ coordinates to epicatechin and probably also catechin (the measurement with catechin was unsuccesfull because of contamination by sodium) between the OH groups at the ring B and the fragmentation of the complex can proceed via a retro-Diels-Alder's reaction and thus lead to cleavage of the pyrone ring. Quercetin has at the pyrone ring the keto function next to the OH group, therefore the iron ion binds to these functions rather than to the OH groups at the ring B. Accordingly, the retro- Diels-Alder's reaction is not possible and the complex loses only small molecules of water and carbon oxide from the side rings as it was found for the complexes of model molecules.
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