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Study of 3D bacterial cellulose production using banana peels as a carbon source
Netopilík, Tibor ; Pernicová, Iva (referee) ; Kovalčík, Adriána (advisor)
This bachelor thesis deals with the study of 3D bacterial cellulose production using Komagataeibacter xylinus using banana peels as a carbon source. The theoretical part deals with the comparison of the properties of bacterial cellulose and plant cellulose, different methods of biotechnological production of bacterial cellulose and its use. The aim of the bachelor thesis was to find out whether it is possible to use banana peel as a carbon source for biotechnological production of bacterial cellulose. Banana peels are waste lignocellulosic material produced, for example, in the production of snacks or fruit or dairy beverages in the food industry. HPLC analysis showed that 1 l of hydrolyzate after enzymatic hydrolysis of 100 g of dry banana peels per 1 l of water contained 8.86 g of glucose and 10.46 g of fructose. The hydrolyzate was used as a carbon source for static and dynamic cultivation of Komagataeibacter xylinus. The yields of bacterial cellulose produced by using banana peels or glucose were compared. The use of banana peels hydrolyzate increased the yields of bacterial cellulose about 170 % in the case of static cultivation and about 220 % in the case of dynamic cultivation. Scanning electron micrographs of bacterial cellulose confirmed the morphological differences between bacterial cellulose produced statically and dynamically. Moreover, the morphology of bacterial cellulose was influenced by the kind of used carbon source.
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Evaluation of grape pomace as carbon source for bacterial cellulose production
Stříž, Radim ; Obruča, Stanislav (referee) ; Kovalčík, Adriána (advisor)
This bachelor thesis is focused on the production of bacterial cellulose by Gluconacetobacter xylinus. The theoretical part consists of a brief description of G. xylinus, properties and uses of bacterial cellulose. Firstly, the experimental part focuses on optimization of production of bacterial cellulose by G. xylinus CCM 4611. This optimization was focused on pH value, a cultivation type, and used carbon source for production. The optimal pH was 6.5. The carbon source showing the highest production of bacterial cellulose was mannose for the dynamic production and saccharose for the static production of bacterial cellulose. The second part of the experimental part focuses on a comparison of two methods for assaying reducing sugars – Somogyi-Nelson (SN) assay and dinitrosalicylic acid (DNS) assay. The comparison of two above mentioned methods showed that the results obtained by the SN method were very close to High performance liquid chromatography (HPLC) data. It can be concluded that HPLC method is the best method if we need to know the type of sugars but if we need only the quick determination of the sum of the reduction sugars, SN method is very suitable. 4 It can be concluded that the Moravian region produces a large amount of winery biomass. Therefore, the use of the pomace extract as a carbon source for the production of bacterial cellulose seems to be interesting mainly from the point of the recirculation economy. The obtained results showed that the grape sugar extract could be used, and from the production values, it is even more suitable for the production of bacterial cellulose than industrial sugars.
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The optimalization of bacterial cellulose production
Stříž, Radim ; Szotkowski, Martin (referee) ; Kovalčík, Adriána (advisor)
This diploma thesis focuses on the optimization of bacterial cellulose production by Komagateibacter xylinus DSM 46604. The theoretical part of this thesis describes the properties of bacterial cellulose, its production and application possibilities. The experimental part aimed to assess the effect of different cultivation conditions on the production yields of bacterial cellulose. The effects of several cultivation strategies have been studied such as: (1) effect of acetate buffer used as a medium, (2) impact of oil added into the medium, (3) fed-batch cultivation, (4) variation of the volume of cultivation vessel and cultivation media and (5) aeration. In addition to the production of relatively thin samples, up to 100 µm was synthesized unique 3D structured bacterial cellulose in the form of cylinders, with a height up to 2 cm. The growth of bacterial cellulose in the form of cylinders was achieved by dynamically cultivating K. xylinus in combination with fed-batch approach.
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Modification of porosity of bacterial cellulose in situ
Ondruchová, Barbora ; Pernicová, Iva (referee) ; Kovalčík, Adriána (advisor)
This bachelor thesis deals with the production and modification of porosity of bacterial cellulose in situ using the bacterium Komagataeibacter xylinus. The theoretical part of the work was focused on the review of various methods of culturing Komagataeibacter xylinus and the production of porous samples of bacterial cellulose. The sizes of pores in bacterial cellulose depend mainly on the applied cultivation method. Bacterial cellulose produced statically or dynamically contains pores with the dimensions of approximately 0.02 µm to 10 µm. The difference in porosity in bacterial cellulose prepared by static and dynamic cultivation was confirmed experimentally. The production yields of bacterial cellulose were compared and discussed. Next, the porosity of the bacterial cellulose was modified in situ by the addition of wax particles. Scanning electron microscopy confirmed, that the accumulation of wax particles in the production medium could significantly support the porosity of bacterial cellulose and, at the same time, increase its production.
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Production of lignin-degrading enzymes by Phanerochaete chrysosporium
Péčiová, Bianka ; Hudečková, Helena (referee) ; Kovalčík, Adriána (advisor)
This diploma thesis deals with the study of the production of ligninolytic enzymes produced by the mold P. chrysosporium and subsequently their immobilization. The theoretical part describes the selected production microorganism, principles of action of ligninolytic enzymes (lignin-peroxidase, manganese-dependent peroxidase and laccase) and methods of their immobilization. In the experimental part, optimal conditions of the production of ligninolytic enzymes by P. chrysosporium were monitored as a composition of culture medium with different glucose content and with using two different inducers: lignin and guaiacol. During the 14-day cultivation cycles, the enzyme activity of lignin-peroxidase, manganese-dependent peroxidase and laccase was monitored on each day of cultivation. Based on the optimized enzyme production procedure, the enzymes were subsequently immobilized by various methods: by method of forming enzyme aggregates (CLEA), adsorption on bacterial cellulose (BC) and a combination of both (CLEA + BC). The CLEA method proved to be the most effective, but there was problem with isolation of enzyme aggregates. Therefore, immobilization on bacterial cellulose associated with the enzymes aggregates was chosen as the most advantageous. With this method, the operational stability of the immobilized enzymes was monitored in 7 consecutive reaction cycles. Subsequently, CLEA and CLEA with BC were used to modify the model phenolic substance, where the alkali lignin was selected. For both sets of immobilizers was confirmed the effect of the enzymes on the lignin structure by measuring the molecular weight (Mw) and polydispersity index (PI).
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Bacterial cellulose based facial mask with antioxidant property
Borová, Šárka ; Hoová, Julie (referee) ; Kovalčík, Adriána (advisor)
This final thesis deals with the preparation of a cosmetic facial mask based on bacterial cellulose. The motivation of this work was to prepare a cosmetic mask with antioxidant properties. To obtain bioactive substances with antioxidant activity, extracts from the rosehip fruits (Rosa Canina L.) with different weight dosages of rosehips and different preservatives were prepared. These rosehip extracts were subjected to spectrophotometric methods, thanks to which the total contents of polyphenols, flavonoids and total antioxidant activity were determined. It was proven that the content of the determined substances increases with the proportion of weighted rose hips and the highest contents of antioxidant substances were measured in extracts with a weight of 25 g of rose hips. Subsequently, these selected extracts were modified into several samples of bacterial cellulose. After the modification of the substances, it was demonstrated that bacterial cellulose is a suitable material for absorbing bioactive substances into the structure of individual analyzed samples. It was found that bacterial celluloses in the form of hydrogel and lyophilized bacterial cellulose were able to absorb the largest amount, of bioactive substances with antioxidant properties. On the other hand, the samples of dry bacterial cellulose and bacterial cellulose with an alginate component absorbed active substances the least. Furthermore, analysis using a Visioscope device revealed that the facial cosmetic mask based on bacterial cellulose in the form of hydrogel could potentially have not only antioxidant but also hydrating effects on the skin.
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Study of 3D bacterial cellulose production using banana peels as a carbon source
Netopilík, Tibor ; Pernicová, Iva (referee) ; Kovalčík, Adriána (advisor)
This bachelor thesis deals with the study of 3D bacterial cellulose production using Komagataeibacter xylinus using banana peels as a carbon source. The theoretical part deals with the comparison of the properties of bacterial cellulose and plant cellulose, different methods of biotechnological production of bacterial cellulose and its use. The aim of the bachelor thesis was to find out whether it is possible to use banana peel as a carbon source for biotechnological production of bacterial cellulose. Banana peels are waste lignocellulosic material produced, for example, in the production of snacks or fruit or dairy beverages in the food industry. HPLC analysis showed that 1 l of hydrolyzate after enzymatic hydrolysis of 100 g of dry banana peels per 1 l of water contained 8.86 g of glucose and 10.46 g of fructose. The hydrolyzate was used as a carbon source for static and dynamic cultivation of Komagataeibacter xylinus. The yields of bacterial cellulose produced by using banana peels or glucose were compared. The use of banana peels hydrolyzate increased the yields of bacterial cellulose about 170 % in the case of static cultivation and about 220 % in the case of dynamic cultivation. Scanning electron micrographs of bacterial cellulose confirmed the morphological differences between bacterial cellulose produced statically and dynamically. Moreover, the morphology of bacterial cellulose was influenced by the kind of used carbon source.
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The optimalization of bacterial cellulose production
Stříž, Radim ; Szotkowski, Martin (referee) ; Kovalčík, Adriána (advisor)
This diploma thesis focuses on the optimization of bacterial cellulose production by Komagateibacter xylinus DSM 46604. The theoretical part of this thesis describes the properties of bacterial cellulose, its production and application possibilities. The experimental part aimed to assess the effect of different cultivation conditions on the production yields of bacterial cellulose. The effects of several cultivation strategies have been studied such as: (1) effect of acetate buffer used as a medium, (2) impact of oil added into the medium, (3) fed-batch cultivation, (4) variation of the volume of cultivation vessel and cultivation media and (5) aeration. In addition to the production of relatively thin samples, up to 100 µm was synthesized unique 3D structured bacterial cellulose in the form of cylinders, with a height up to 2 cm. The growth of bacterial cellulose in the form of cylinders was achieved by dynamically cultivating K. xylinus in combination with fed-batch approach.
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Modification of porosity of bacterial cellulose in situ
Ondruchová, Barbora ; Pernicová, Iva (referee) ; Kovalčík, Adriána (advisor)
This bachelor thesis deals with the production and modification of porosity of bacterial cellulose in situ using the bacterium Komagataeibacter xylinus. The theoretical part of the work was focused on the review of various methods of culturing Komagataeibacter xylinus and the production of porous samples of bacterial cellulose. The sizes of pores in bacterial cellulose depend mainly on the applied cultivation method. Bacterial cellulose produced statically or dynamically contains pores with the dimensions of approximately 0.02 µm to 10 µm. The difference in porosity in bacterial cellulose prepared by static and dynamic cultivation was confirmed experimentally. The production yields of bacterial cellulose were compared and discussed. Next, the porosity of the bacterial cellulose was modified in situ by the addition of wax particles. Scanning electron microscopy confirmed, that the accumulation of wax particles in the production medium could significantly support the porosity of bacterial cellulose and, at the same time, increase its production.
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Evaluation of grape pomace as carbon source for bacterial cellulose production
Stříž, Radim ; Obruča, Stanislav (referee) ; Kovalčík, Adriána (advisor)
This bachelor thesis is focused on the production of bacterial cellulose by Gluconacetobacter xylinus. The theoretical part consists of a brief description of G. xylinus, properties and uses of bacterial cellulose. Firstly, the experimental part focuses on optimization of production of bacterial cellulose by G. xylinus CCM 4611. This optimization was focused on pH value, a cultivation type, and used carbon source for production. The optimal pH was 6.5. The carbon source showing the highest production of bacterial cellulose was mannose for the dynamic production and saccharose for the static production of bacterial cellulose. The second part of the experimental part focuses on a comparison of two methods for assaying reducing sugars – Somogyi-Nelson (SN) assay and dinitrosalicylic acid (DNS) assay. The comparison of two above mentioned methods showed that the results obtained by the SN method were very close to High performance liquid chromatography (HPLC) data. It can be concluded that HPLC method is the best method if we need to know the type of sugars but if we need only the quick determination of the sum of the reduction sugars, SN method is very suitable. 4 It can be concluded that the Moravian region produces a large amount of winery biomass. Therefore, the use of the pomace extract as a carbon source for the production of bacterial cellulose seems to be interesting mainly from the point of the recirculation economy. The obtained results showed that the grape sugar extract could be used, and from the production values, it is even more suitable for the production of bacterial cellulose than industrial sugars.
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