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Study of bioactive compounds of fennel
Mierna, Jana ; Skoumalová, Petra (referee) ; Veselá, Mária (advisor)
The master´s thesis is focused on the study of biologically active compounds of fennel. The theoretical part describes basic characteristics of fennel and its chemical composition, further specifies plant´s biological active substances and antioxidants, also describes extraction techniques for obtaining these bioactive compounds, methods of their determination and verification of antimicrobial effect. In the experimental part were spectrophotometrically determined contents of polyphenols and flavonoids in the prepared extracts of fennel tea, whole and crush spice. On the basis of extraction curves, antioxidant activity and potential antimicrobial activity against the selected microorganisms Bacillus subtilis, Bacillus cereus, Serratia marcescens a Micrococcus luteus was determined in the samples with the highest values of the given bioactive substances. Among the all monitored extracts, the inhibitory effect was showed only by an aqueous extract of the fennel tea against the bacterial strain of Micrococcus luteus.
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Antimicrobial activity of rosehip teas
Ďubašáková, Mária ; Vespalcová, Milena (referee) ; Veselá, Mária (advisor)
The aim of this bachelor theses was to determine the concentration of biologically active substances such as polyphenols and flavonoids and also total antioxidant activity of tea extract of rosehip and also research antimicrobial activity and the effective concentration of the extracts against selected bacteria. Theoretical part is focuses on the description of natural antioxidants and active effect against free radicals, description and distribution of tea, botanical and chemical description od rosehip and basic information about bacteria. There is section describe selected methods for the determination of polyphenols, flavonoids, total antioxidant activity of these extracts, and verification of antimicrobial activity against grampositive and gramnegative bacteria in experimental section. From the results is flow, that the analyzed extracts have no inhibition activity against bacteria. Also was found that aqueous extracts has high proportion flavonoids and polyphenols.
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Extraction of anthocyanin pigments from black chokeberry pomace
Martinková, Patrícia ; Zemanová, Jana (referee) ; Vespalcová, Milena (advisor)
The diploma thesis deals with the preparation of extract and concentrate of anthocyanin dyes from aronia moldings (Aronia melanocarpa). It also determines chemical properties important for human´s health, which are important also for further possible use of extract/concentrate as natural red food coloring. A series of extractions of dried and powdered aronia moldings was carried out in the experimental part of the thesis, aiming for the optimization the conditions of the extraction. Extracts were characterized by content of total anthocyans, content of total fenolic substances and total antioxidant activity. The best laboratory conditions for extraction were determined as follows: amount of moldings 12,5 g, composition of extraction agent ethanol:water 1:1, volume of extraction mixture 60 ml and time of the extraction 11 hours. Prepared extracts were concentrated on vacuum evaporator. It has been found that the temperature of the water bath in the vacuum evaporator can not exceed 40 °C. At higher temperatures there is significant degradation of anthocyanins. Furthemore, the content of individual anthocyanic dyes in extract and concentrate, from aronia moldings, was quantified by HPLC. The major anthocyanin, cyanidine-3-galactoside, was contained in the concentrate at 923,6 ± 8,5 mg·l-1, the other specified anthocyanin, minor cyanidine-3-glucoside, was present at a concentration of 53,5 ± 0,3 mg·l-1.
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Sea buckthorn – the source of natural compounds
Blašková, Daniela ; Vítová, Eva (referee) ; Veselá, Mária (advisor)
The main aim of the bachelor thesis was a research of common sea buckthorn, often denoted as "a plant of future". Botanic characteristics of the given bush, verification of biologically active substances and various concentration extract effects on selected kinds of microorganisms. In the theoretical part, the literature search is done, which discusses the characterization of the researched plant. The practical part deals with the application of selected methods of research, as follows: spectrophotometric determination of biologically active substances and microbiological verification of microbial activity on microorganisms, such as Bacillus subtilis, Serratia marcenscens and Micrococcus luteus. Considering the thesis results, it ensues that the given extracts do not show too great bacterial activity. Ex adverso, the extracts contain too big amount of determined active substances, in some cases.
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Bioactive substances of rose hip
Ďubašáková, Mária ; Skoumalová, Petra (referee) ; Veselá, Mária (advisor)
The aim of this master´s thesis was to determine the concentration of bioactive substances such as total polyphenols and flavonoids as well as the total antioxidant capacity in tea extracts from Rosa canina. In the second part, an experiment was found to detect antimicrobial activity and an effective concentration of ethanol against selected bacteria. The theoretical part is focused on description of natural antioxidants and their effect on free radicals, description of tea, description of rose hazel and possibilities of spectrophotometric determination of natural substances and eventually basic distribution of bacteria. In the experimental part, ethanol and aqueous extracts were prepared in which the total number of polyphenols, flavonoids and antioxidant effects. The results of the determination of polyphenols and flavonoids show that the solvent with ethanol is more suitable for flower fermentation and water is more suitable for dropping the rose. Comparison of the antioxidant activity of macerates showed no significant differences; slightly higher antioxidant activity showed macerates from pink flowers. The extracts showed antimicrobial activity against Micrococcus luteus and slightly against Bacillus cereus. The highest antimicrobial activity was determined for the micrococcus luteus
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Extraction of anthocyanin pigments from black chokeberry pomace
Martinková, Patrícia ; Zemanová, Jana (referee) ; Vespalcová, Milena (advisor)
The diploma thesis deals with the preparation of extract and concentrate of anthocyanin dyes from aronia moldings (Aronia melanocarpa). It also determines chemical properties important for human´s health, which are important also for further possible use of extract/concentrate as natural red food coloring. A series of extractions of dried and powdered aronia moldings was carried out in the experimental part of the thesis, aiming for the optimization the conditions of the extraction. Extracts were characterized by content of total anthocyans, content of total fenolic substances and total antioxidant activity. The best laboratory conditions for extraction were determined as follows: amount of moldings 12,5 g, composition of extraction agent ethanol:water 1:1, volume of extraction mixture 60 ml and time of the extraction 11 hours. Prepared extracts were concentrated on vacuum evaporator. It has been found that the temperature of the water bath in the vacuum evaporator can not exceed 40 °C. At higher temperatures there is significant degradation of anthocyanins. Furthemore, the content of individual anthocyanic dyes in extract and concentrate, from aronia moldings, was quantified by HPLC. The major anthocyanin, cyanidine-3-galactoside, was contained in the concentrate at 923,6 ± 8,5 mg·l-1, the other specified anthocyanin, minor cyanidine-3-glucoside, was present at a concentration of 53,5 ± 0,3 mg·l-1.
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Bioactive substances of rose hip
Ďubašáková, Mária ; Skoumalová, Petra (referee) ; Veselá, Mária (advisor)
The aim of this master´s thesis was to determine the concentration of bioactive substances such as total polyphenols and flavonoids as well as the total antioxidant capacity in tea extracts from Rosa canina. In the second part, an experiment was found to detect antimicrobial activity and an effective concentration of ethanol against selected bacteria. The theoretical part is focused on description of natural antioxidants and their effect on free radicals, description of tea, description of rose hazel and possibilities of spectrophotometric determination of natural substances and eventually basic distribution of bacteria. In the experimental part, ethanol and aqueous extracts were prepared in which the total number of polyphenols, flavonoids and antioxidant effects. The results of the determination of polyphenols and flavonoids show that the solvent with ethanol is more suitable for flower fermentation and water is more suitable for dropping the rose. Comparison of the antioxidant activity of macerates showed no significant differences; slightly higher antioxidant activity showed macerates from pink flowers. The extracts showed antimicrobial activity against Micrococcus luteus and slightly against Bacillus cereus. The highest antimicrobial activity was determined for the micrococcus luteus
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Study of bioactive compounds of fennel
Mierna, Jana ; Skoumalová, Petra (referee) ; Veselá, Mária (advisor)
The master´s thesis is focused on the study of biologically active compounds of fennel. The theoretical part describes basic characteristics of fennel and its chemical composition, further specifies plant´s biological active substances and antioxidants, also describes extraction techniques for obtaining these bioactive compounds, methods of their determination and verification of antimicrobial effect. In the experimental part were spectrophotometrically determined contents of polyphenols and flavonoids in the prepared extracts of fennel tea, whole and crush spice. On the basis of extraction curves, antioxidant activity and potential antimicrobial activity against the selected microorganisms Bacillus subtilis, Bacillus cereus, Serratia marcescens a Micrococcus luteus was determined in the samples with the highest values of the given bioactive substances. Among the all monitored extracts, the inhibitory effect was showed only by an aqueous extract of the fennel tea against the bacterial strain of Micrococcus luteus.
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Sea buckthorn – the source of natural compounds
Blašková, Daniela ; Vítová, Eva (referee) ; Veselá, Mária (advisor)
The main aim of the bachelor thesis was a research of common sea buckthorn, often denoted as "a plant of future". Botanic characteristics of the given bush, verification of biologically active substances and various concentration extract effects on selected kinds of microorganisms. In the theoretical part, the literature search is done, which discusses the characterization of the researched plant. The practical part deals with the application of selected methods of research, as follows: spectrophotometric determination of biologically active substances and microbiological verification of microbial activity on microorganisms, such as Bacillus subtilis, Serratia marcenscens and Micrococcus luteus. Considering the thesis results, it ensues that the given extracts do not show too great bacterial activity. Ex adverso, the extracts contain too big amount of determined active substances, in some cases.
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Antimicrobial activity of rosehip teas
Ďubašáková, Mária ; Vespalcová, Milena (referee) ; Veselá, Mária (advisor)
The aim of this bachelor theses was to determine the concentration of biologically active substances such as polyphenols and flavonoids and also total antioxidant activity of tea extract of rosehip and also research antimicrobial activity and the effective concentration of the extracts against selected bacteria. Theoretical part is focuses on the description of natural antioxidants and active effect against free radicals, description and distribution of tea, botanical and chemical description od rosehip and basic information about bacteria. There is section describe selected methods for the determination of polyphenols, flavonoids, total antioxidant activity of these extracts, and verification of antimicrobial activity against grampositive and gramnegative bacteria in experimental section. From the results is flow, that the analyzed extracts have no inhibition activity against bacteria. Also was found that aqueous extracts has high proportion flavonoids and polyphenols.
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