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Aronia as a raw material for cosmetic production
Palkovská, Kateřina ; Sýkora, Michal (referee) ; Zemanová, Jana (advisor)
This bachelor thesis deals with extraction of polyphenols from fruits and leaves of aronia and consequent use of obtained extract in cosmetic production. In the theoretical part are information about the origin of the aronia, the botanical characteristics of Aronia Melanocarpa and about its utilization. Furthermore, the chemical composition of the plant material of the aronia is described, which is also common for fruits. At the end of the theoretical part are described extraction and separation techniques, methods of determination of total polyphenolic compounds and brief characteristics of the material safety data sheet. The experimental part describes the optimization of the prepared extract so that the extract contains as many polyphenolic compounds as possible. 50% ethanol at room temperature was shown to be optimal for leaf and fruit extraction, and the maceration time was found to have a significant effect on the polyphenolic compounds obtained. For the obtained optimized macerate, some chemical and physical properties such as pH, density, refractive index were determined for the purpose of producing a material safety data sheet and product specification. At the end of the experimental part were prepared cosmetic products with the addition of macerate from crushed aronia fruits.
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Monitoring of cereal products uptake in a sample of Czech population
Vlachová, Martina ; Hurtová, Jana (referee) ; Márová, Ivana (advisor)
This bachelor’s thesis was focused on monitoring of consumption of cereal products and analysis of some of their active components. In theoretical part an overwiev of cereals and their composition was introduced. In experimental part a set of analytical parameters was obtained in selected cereal products: total phenolics, total flavonoids and antioxidant activity. The highest level of these active substances was detected in products containing chocolate and forest fruit. Further, 161 completed consumer questionnaires were collected. From these data common knowledge in consumers, their shopping conventions and individual products preferences were evaluated.
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Changes of antioxidants in selected fruits during long-term freezing
Štindlová, Jitka ; Lichnová, Andrea (referee) ; Márová, Ivana (advisor)
In this bachelor thesis some low molecular weight antioxidants contained in strawberries, raspberries, blueberries and cranberries are described. In the theoretical part also general characteristics of these fruits are introduced. Experimental part was focused on analysis of the changes of selected antioxidant content in the fruits. These changes were monitored during storage in two different conditions – in refrigerator and in freezer. In refrigerator whole fruits were stored for 8 days. The experiment in the freezer was performed for 2 months and the fruits were stored in four different processed forms – as a whole fruit, whole fruit impregnated by sucrose solution, as a pulp and pulp mixed with sucrose. Antioxidant content in fruits was analyzed by HPLC and spectrophotometry. The highest total content of antioxidants was found in strawberries, while the lowest values were found in raspberries. During storage some part of original antioxidant content stayed conserved, the highest content was preserved in blueberries processed as a whole fruits and impregnated whole fruits.
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Changes of the content of some active substances in aplle and pear fruits during storage
Matějková, Markéta ; Halienová, Andrea (referee) ; Márová, Ivana (advisor)
In presented bachelor thesis low molecular substances antioxidants found in plant food were described. Antioxidants from apples and pears were studied in detail, particularly their changes during storage in different conditions. Fruit species were described more closely in this study. The theoretical part is focused on ripening and storage of the fruits. The most common diseases of apples and pears are introduced too. In the practical part changes of some antioxidant levels in apples Idared (red-yellow) and Golden Delicious (green-yellow) were analyzed. Apples were stored for 2 months in three various storage conditions – at standard ambient temperature in the lab, in cellar and in refrigerator. In regular intervals samples were taken and levels of low molecular antioxidants (vitamin C, total phenolics, total flavonoids) and total antioxidant activity in apple fruits were analysed and compared. A surface microflora of the apples was analysed during the whole storage time. The most suitable storage conditions exhibited cellar (9 °C, 38,4 %). Phenolic changes in apples were substantially lower than flavonoid changes, while ascorbate content decreased dramatically with the storage time. Antioxidant activity was related mainly to ascorbate levels, influence of flavonoid changes was observed too. Antioxidant parameters were analyzed also in pear fruits, whose were stored only for very short time.
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Aronia as a raw material for cosmetic production
Palkovská, Kateřina ; Sýkora, Michal (referee) ; Zemanová, Jana (advisor)
This bachelor thesis deals with extraction of polyphenols from fruits and leaves of aronia and consequent use of obtained extract in cosmetic production. In the theoretical part are information about the origin of the aronia, the botanical characteristics of Aronia Melanocarpa and about its utilization. Furthermore, the chemical composition of the plant material of the aronia is described, which is also common for fruits. At the end of the theoretical part are described extraction and separation techniques, methods of determination of total polyphenolic compounds and brief characteristics of the material safety data sheet. The experimental part describes the optimization of the prepared extract so that the extract contains as many polyphenolic compounds as possible. 50% ethanol at room temperature was shown to be optimal for leaf and fruit extraction, and the maceration time was found to have a significant effect on the polyphenolic compounds obtained. For the obtained optimized macerate, some chemical and physical properties such as pH, density, refractive index were determined for the purpose of producing a material safety data sheet and product specification. At the end of the experimental part were prepared cosmetic products with the addition of macerate from crushed aronia fruits.
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Monitoring of cereal products uptake in a sample of Czech population
Vlachová, Martina ; Hurtová, Jana (referee) ; Márová, Ivana (advisor)
This bachelor’s thesis was focused on monitoring of consumption of cereal products and analysis of some of their active components. In theoretical part an overwiev of cereals and their composition was introduced. In experimental part a set of analytical parameters was obtained in selected cereal products: total phenolics, total flavonoids and antioxidant activity. The highest level of these active substances was detected in products containing chocolate and forest fruit. Further, 161 completed consumer questionnaires were collected. From these data common knowledge in consumers, their shopping conventions and individual products preferences were evaluated.
|
|
|
Changes of antioxidants in selected fruits during long-term freezing
Štindlová, Jitka ; Lichnová, Andrea (referee) ; Márová, Ivana (advisor)
In this bachelor thesis some low molecular weight antioxidants contained in strawberries, raspberries, blueberries and cranberries are described. In the theoretical part also general characteristics of these fruits are introduced. Experimental part was focused on analysis of the changes of selected antioxidant content in the fruits. These changes were monitored during storage in two different conditions – in refrigerator and in freezer. In refrigerator whole fruits were stored for 8 days. The experiment in the freezer was performed for 2 months and the fruits were stored in four different processed forms – as a whole fruit, whole fruit impregnated by sucrose solution, as a pulp and pulp mixed with sucrose. Antioxidant content in fruits was analyzed by HPLC and spectrophotometry. The highest total content of antioxidants was found in strawberries, while the lowest values were found in raspberries. During storage some part of original antioxidant content stayed conserved, the highest content was preserved in blueberries processed as a whole fruits and impregnated whole fruits.
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Changes of the content of some active substances in aplle and pear fruits during storage
Matějková, Markéta ; Halienová, Andrea (referee) ; Márová, Ivana (advisor)
In presented bachelor thesis low molecular substances antioxidants found in plant food were described. Antioxidants from apples and pears were studied in detail, particularly their changes during storage in different conditions. Fruit species were described more closely in this study. The theoretical part is focused on ripening and storage of the fruits. The most common diseases of apples and pears are introduced too. In the practical part changes of some antioxidant levels in apples Idared (red-yellow) and Golden Delicious (green-yellow) were analyzed. Apples were stored for 2 months in three various storage conditions – at standard ambient temperature in the lab, in cellar and in refrigerator. In regular intervals samples were taken and levels of low molecular antioxidants (vitamin C, total phenolics, total flavonoids) and total antioxidant activity in apple fruits were analysed and compared. A surface microflora of the apples was analysed during the whole storage time. The most suitable storage conditions exhibited cellar (9 °C, 38,4 %). Phenolic changes in apples were substantially lower than flavonoid changes, while ascorbate content decreased dramatically with the storage time. Antioxidant activity was related mainly to ascorbate levels, influence of flavonoid changes was observed too. Antioxidant parameters were analyzed also in pear fruits, whose were stored only for very short time.
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Biologically significant substances in cereal products
Vondráčková, Hedvika ; Halienová, Andrea (referee) ; Márová, Ivana (advisor)
Presented work was focused on study of biologically significant substances in cereal products. In experimental part selected active substances in cereal bars were analyzed. The highest content of total phenolics, total flavonoids, total antioxidant capacity, procyanidin B2 and chlorogenic acid was measured in plums and blueberry bars. The highest level of reduced saccharides was evaluated in raspberry and cereal bars. Presence of main simple sugars - maltose, glucose and fructose was detected in all bar samples.
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