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Isolation of active substances with antioxidative properties from lignocellulosic waste
Jurová, Karolína ; Vítová, Eva (referee) ; Kovalčík, Adriána (advisor)
This thesis focuses on isolating active substances with antioxidant properties from lignocellulosic wastes. This work aimed to modify bacterial cellulose (BC) with extracts from grape pomace, which show high antioxidant activity. Grape pomace belongs to the group of lignocellulosic wastes with high content of bioactive compounds such as polyphenols, which contribute significantly to antioxidant efficacy. This work tested the hypothesis that grape extracts can provide antioxidative efficiency to BC. Grape pomace extracts were prepared from grape pomace frozen and lyophilized using a 70% acetone, a 70% ethanol or a 50% ethanol solvent. The highest values of antioxidant activity were determined for the lyophilized extract prepared by extracting grape pomace with 70% acetone. The extracts were further used to modify bacterial cellulose in the form of films (dry BC) and hydrogels (wet BC). It was shown that both forms of BC could be effectively modified using grape pomace extracts, but BC hydrogel achieved higher antioxidant activity compared to BC film. Furthermore, BC with antioxidant activity can be used in various food, cosmetics, and medicine applications.
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Use of secondary raw materials from wine production
Lajtman, Roman ; Vespalcová, Milena (referee) ; Diviš, Pavel (advisor)
This bachelor thesis deals with using of grape pomace, waste from wine industry. It also deals with the determining of total phenolic substances in a grape pomace. The theoretical part focuses on the characteristic of grape, the chemical composition of wine, making of wine and mainly on use of secondary raw materials. It also describes phenolic substances, their division and finally something general about using experimental methods. In the experimental part a red grape pomace´s extraction was made. The extractions were made in different solvents, in a mixture ethanol-water (ratio 20:80; 40:60 and 60:40), also in a mixture glycerol-water (ratio 10:90; 20:80 and 40:60) and at the end in water. The extractions were made in a different time and the purpose was to optimize the extractions and to get the highest yield of phenolic substances, antioxidants. Time and economically side played an important role to find out and to choose the best solvent. In the results, as the best and the optimal extraction´s solvent on extraction of red grape pomace was chosen the mixture ethanol-water and ratio was 60:40. That mixture extracted the most phenolic substances and relatively in the shortest time. During the optimization of sample weight was found out that optimal sample weight is 4 g of grape pomace. At the end repeated extraction was made. It is obviously practically worthless. After second step of extraction, the concentration of phenolic substances is more than a half lower than at the first step.
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Biotechnological production of PHA from waste substrates
Krejčiřík, Roman ; Hrabalová, Vendula (referee) ; Obruča, Stanislav (advisor)
The presented bachelor thesis deals with the study of polyhydroxyalkanoates using wine grape pomace extract. The thesis aims to determine whether it is possible to use wine grape pomace extract as a substrate for polyhydroxyalkanoates (PHA) production. For this research, four thermophilic bacterial strains were selected such as Schlegelella thermodepolymerans, Caldimonas meghalayensis, natural isolate labeled as 34, and Tepidimonas taiwanensis, from which the most suitable bacterium was subsequently selected. The best transformation of residual sugars showed T. taiwanensis, and therefore it was used for all the further fermentation. The extracts were prepared out of wine marc of Veltlínské červené rané, Müller Thurgau, Pálava, Sauvignon, Rulandské bílé, Frankovka (rosé), Frankovka (red wine). The highest PHA concentration was detected after fermentation with concentrated extracts of Sauvignon and Rulandské bílé. Fermentation processes in other extracts were most likely inhibited by the components they contained. Optimization was performed by dilution of extracts with water. The highest concentrations of PHA while using dilute extracts were achieved with the extract from different kinds of Frankovka (rosé) and Frankovka (red wine).
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Biotechnological production of PHA from waste substrates
Krejčiřík, Roman ; Hrabalová, Vendula (referee) ; Obruča, Stanislav (advisor)
The presented bachelor thesis deals with the study of polyhydroxyalkanoates using wine grape pomace extract. The thesis aims to determine whether it is possible to use wine grape pomace extract as a substrate for polyhydroxyalkanoates (PHA) production. For this research, four thermophilic bacterial strains were selected such as Schlegelella thermodepolymerans, Caldimonas meghalayensis, natural isolate labeled as 34, and Tepidimonas taiwanensis, from which the most suitable bacterium was subsequently selected. The best transformation of residual sugars showed T. taiwanensis, and therefore it was used for all the further fermentation. The extracts were prepared out of wine marc of Veltlínské červené rané, Müller Thurgau, Pálava, Sauvignon, Rulandské bílé, Frankovka (rosé), Frankovka (red wine). The highest PHA concentration was detected after fermentation with concentrated extracts of Sauvignon and Rulandské bílé. Fermentation processes in other extracts were most likely inhibited by the components they contained. Optimization was performed by dilution of extracts with water. The highest concentrations of PHA while using dilute extracts were achieved with the extract from different kinds of Frankovka (rosé) and Frankovka (red wine).
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Use of secondary raw materials from wine production
Lajtman, Roman ; Vespalcová, Milena (referee) ; Diviš, Pavel (advisor)
This bachelor thesis deals with using of grape pomace, waste from wine industry. It also deals with the determining of total phenolic substances in a grape pomace. The theoretical part focuses on the characteristic of grape, the chemical composition of wine, making of wine and mainly on use of secondary raw materials. It also describes phenolic substances, their division and finally something general about using experimental methods. In the experimental part a red grape pomace´s extraction was made. The extractions were made in different solvents, in a mixture ethanol-water (ratio 20:80; 40:60 and 60:40), also in a mixture glycerol-water (ratio 10:90; 20:80 and 40:60) and at the end in water. The extractions were made in a different time and the purpose was to optimize the extractions and to get the highest yield of phenolic substances, antioxidants. Time and economically side played an important role to find out and to choose the best solvent. In the results, as the best and the optimal extraction´s solvent on extraction of red grape pomace was chosen the mixture ethanol-water and ratio was 60:40. That mixture extracted the most phenolic substances and relatively in the shortest time. During the optimization of sample weight was found out that optimal sample weight is 4 g of grape pomace. At the end repeated extraction was made. It is obviously practically worthless. After second step of extraction, the concentration of phenolic substances is more than a half lower than at the first step.
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