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The enzymatic hydrolysis of waste paper - a source of raw materials for production of liquid biofuels
Lepař, Petr ; Stloukal, Radek (referee) ; Gabriel, Petr (advisor)
In diploma thesis the process of enzymatic hydrolysis of waste paper as a source for the production of liquid biofuels is discused. It follows directly the homonymous diploma thesis from Ing. Brummer, and it is based on the findings, which were solved and decided in previous work. In the theoretical part there is a summarization of basic information on the enzymatic hydrolysis of waste paper and the associated influences of various factors of the rate and degree of hydrolysis. Higher attention is paid to a waste cardboard and its pretreatment methods due to the maximalization of the yield of hydrolysis. The next part summarizes options of the fermentative production of biofuels, focusing on the method of simultaneous saccharification and fermentation, where the further appropriate organism for ethanol fermentation is discussed. The last part is about the technological process from the raw material input to the separation of ethanol. In the experimental section the pre-treatment of waste paper in order to maximize the efficiency of hydrolysis was examined. The best results were achieved using a vibratory mill. In addition, various parameters for simultaneous saccharification and fermentation were optimized using enzymes from Novozymes® company and the yeast Saccharomyces cerevisiae. The conversion rate of waste paper cellulose to reducing sugars was observed by spectrophotometric method by Somogyi - Nelson and the amount of produced ethanol was quantified using HPLC / RI. As a part of this thesis some conditions (amount of enzyme, substrate, nutrients, yeasts, temperature, pH, type of buffer) were optimized to maximize the effectiveness of the overall process. All experiments were carried out on corrugated cardboard, which was chosen as the most promising material for hydrolysis that was among the waste paper pulp in diploma thesis by Ing. Brummer.
Study on pretreatment and hydrolysis of selected lignocellulose materials
Kovářová, Markéta ; Dvořák, Miloš (referee) ; Obruča, Stanislav (advisor)
This diploma thesis is focused on study of chemical and enzymatical hydrolysis of raw wood material. The aim of this work was to find the suitable method for pretreatment of selected lignocellulose materials. The theoretical part deals with characterization of lignocellulosic material and its components. There are also subscribed various pretreatment methods and their effect on hydrolysis of sawdust. In experimental part of the work the most appropriate approach of pretreatment and hydrolysis of sawdust was studied. Criteria for the selection of suitable method was concentration of saccharides as desired product of hydrolysis and also concentration of the most important microbial inhibitors - polyphenols. Application of 96% ethanol or 5% H2O2 were identified as the most promising pretreatment methods which enhanced yields of fermentable sugars about 30 %. Further, we also performed cultivation of bacteria Burkholderia cepacia and bacteria Burkholderia sacchari using solution obtained by hydrolysis of lignocellulose material.
Use of wastes from winemaking in food and cosmetics applications
Výmolová, Markéta ; Němcová, Andrea (referee) ; Márová, Ivana (advisor)
The presented thesis deals with the various types of hydrolysis of waste from the production of wine, parings and bunch-stems for subsequent biotechnological use as enrichment of feeding mixtures and the production of bio-ethanol. A composite analysis was done at the start of the measurements for the determination of dry matter, extraction of oil from the parings and assessment of cellulose in the bunch-stems. As a part of this thesis a chemical and enzyme hydrolysis of waste materials have been performed. In hydrolysates the contents of reducing carbohydrates and antioxidants, polyphenols and flavonoids were analysed. The results showed that the samples with a concentration of 50 g/l of material hydrolysed in a water bath for 60 minutes were the best conditions for cultivating yeasts. Hydrolysed parings and bunch-stems were used as the production medium for the production of ethanol in Saccharomyces cerevisiae. A change of the concentration of carbohydrates and ethanol in the samples has been measured by HPLC. The sample hydrolysed enzymatically using cellulase exhibited the highest concentration of biomass (c = 2,140 g/l), the sample hydrolysed chemically in the water bath formed the highest content of ethanol (c = 9,880 g/l).
Waste materials utilization for preparing hydrolysates for the fermentation phase.
Vadovičová, Natália ; Hrstka, Miroslav (referee) ; Babák, Libor (advisor)
Bachelor thesis focuses on the study and comparison of different types of hydrolysis, their optimization and maximization of yields for the upcoming fermentation. Orange peel was chosen as a substrate to conduct the experiments. First, the substrate was mechanically grinded to form a suspension. Each suspension then underwent one out of the examined methods of hydrolysis. Chosen methods were physical, such as microwaves, increased temperature or ultrasound, and chemical acidic and alkaline. Combinations of both types were also examined. The last optimized method was enzymatic hydrolysis. First set of experiments was conducted using enzymes Novozymes® NS50013 and NS50010. Production of cellulase and pectinase enzymes by A. niger during solid-state fermentation that lasted 10 days was also studied. The yields of reducing sugars of all the experiments were calculated using the Somogyi-Nelson method. Enzymatic hydrolysis was proven to be the most effective using the combination of both of the enzymes for a period of 96 hours at pH = 4.5 and temperature 45 °C. Yield of the reducing sugars under these conditions reached 27,4241 ± 0,0007 gl-1.
Biotechnological production of polyhydroxyalkanoates using wastes of coffee production
Vašíčková, Monika ; Benešová, Pavla (referee) ; Obruča, Stanislav (advisor)
This bachelor thesis is focused on study of production of polyhydroxyalkanoates (PHA) by bacteria Burkholderia cepacia and Burkholderia sacchari. Production of PHA has been studied using spent coffee grounds hydrolysates which have been prepared by different aproaches. In the thesis is compared standard method of coffee ground hydrolysis by mineral acid followed by enzymatic hydrolysis. Hydrolysates which have been produced were analyzed in terms of concentration of saccharides and efficiency of hydrolysis. The best producer of PHA (based on results) was bacterium Burkholderia cepacia, in the medium which has been prepared by hydrolysis of spent coffee grounds extracted by 60% solution of ethanol. Biomass yield of this cultivation was 3,553 g/l with 32,472% PHA content. This PHA contained 6,09% 3-hydroxyvalerate. In the other experiment, we verified alternative hydrolysis of spent coffee grounds – by commercially available enzymes. We used cellulase, hemicellulase and the enzymatic cocktail which has been produced by mould. Hemicellulase was the most effective hydrolytic enzyme and its application resulted in production of the highest amount of biomass – 5,708 g/l. In this cultivation, only homopolymer PHB has been which is probably caused by the fact, that during the enzymatic hydrolysis levulinic acid or any other potential precursor of 3HV is formed.
Study of growth and optimization of selected metabolites production by Zymomonas mobilis
Lukačková, Adéla ; Vránová, Dana (referee) ; Babák, Libor (advisor)
In the diploma thesis are discussed the process of enzymatic hydrolysis of waste paper as a source for the production of bioethanol by bacteria Zymomonas mobilis. In the theoretical part summarize basic information about particular methods of hydrolysis, about paper used as a raw material for enzymatic hydrolysis, about possibilities of the fermentative production of bioethanol focusing on the method of simultaneous saccharification and fermentation comparison with enzymatic hydrolysis and fermentation. Suitable microorganisms for ethanolic fermentation and simultaneous saccharification and fermentation and their advantages and disadvantages, are further discussed in this part as well. The theoretical part ends with the suggestion of the technological process for production of bioetanol. It covers all necessary steps from the input of raw material to the separation of produced ethanol. In the experimental part various parameters of hydrolysis, fermentation and simultaneous saccharification and fermentation were optimized using enzymes from Novozymes® company and the Zymomonas mobilis CCM2770 and Zymomonas mobilis LMG457 bacterium. The conversion rate of paper cellulose to gluckose and production of ethanol were observed by HPLC/RI method. Type of buffer, quantity of cells, enzyme and substrate were optimized in order to maximize the efficiency of the process. All experiments were performed on paper containing high amount of cellulose and for comparison on standard medium which contains gluckose. The highest yields was achieved with the use of Novozymes® Cellulosic ethanol enzyme Kit. The strain Zymomonas mobilis LMG457 has demonstrated as a better producer.
Analysis of phospholipids by comprehensive gas chromatography
Šilhavecká, Simona ; Čabala, Radomír (advisor) ; Jelínek, Ivan (referee)
Phospholipids are an important group of polar lipids constituting the main component of cell membranes. Their proportion may vary depending on many factors of the surrounding environment in which the cell is located. Determination of membrane phospholipids is essential in many scientific, industrial and economic sectors. The aim of this work has been to develop a separation method for determination of membrane phospholipids by which it was possible to analyze phosphorylated parts of phospholipids and fatty acids from one sample. Comprehensive gas chromatography with mass detection (GC×GC-MS) was chosen for the assay. This method allows the separation of the entire sample on two serially connected different columns, among which is the interface called modulator. The preparation of the sample includes a cleavage of the phospholipid molecule by the enzyme phospholipase C, which released the phosphorylated polar headgroups. These polar parts had to be derivatized before analysis. The principle of the chosen derivatization consisted in the use of two different silylation agents (hexamethyldisilazane and N,O-Bis(trimethylsilyl) trifluoracetamide) in two steps. Conditions were selected for efficient separation of the silylderivatives of phosphorylated headgroups using GC×GC-MS using a cryogenic...
Study on pretreatment and hydrolysis of selected lignocellulose materials
Kovářová, Markéta ; Dvořák, Miloš (referee) ; Obruča, Stanislav (advisor)
This diploma thesis is focused on study of chemical and enzymatical hydrolysis of raw wood material. The aim of this work was to find the suitable method for pretreatment of selected lignocellulose materials. The theoretical part deals with characterization of lignocellulosic material and its components. There are also subscribed various pretreatment methods and their effect on hydrolysis of sawdust. In experimental part of the work the most appropriate approach of pretreatment and hydrolysis of sawdust was studied. Criteria for the selection of suitable method was concentration of saccharides as desired product of hydrolysis and also concentration of the most important microbial inhibitors - polyphenols. Application of 96% ethanol or 5% H2O2 were identified as the most promising pretreatment methods which enhanced yields of fermentable sugars about 30 %. Further, we also performed cultivation of bacteria Burkholderia cepacia and bacteria Burkholderia sacchari using solution obtained by hydrolysis of lignocellulose material.
Waste materials utilization for preparing hydrolysates for the fermentation phase.
Vadovičová, Natália ; Hrstka, Miroslav (referee) ; Babák, Libor (advisor)
Bachelor thesis focuses on the study and comparison of different types of hydrolysis, their optimization and maximization of yields for the upcoming fermentation. Orange peel was chosen as a substrate to conduct the experiments. First, the substrate was mechanically grinded to form a suspension. Each suspension then underwent one out of the examined methods of hydrolysis. Chosen methods were physical, such as microwaves, increased temperature or ultrasound, and chemical acidic and alkaline. Combinations of both types were also examined. The last optimized method was enzymatic hydrolysis. First set of experiments was conducted using enzymes Novozymes® NS50013 and NS50010. Production of cellulase and pectinase enzymes by A. niger during solid-state fermentation that lasted 10 days was also studied. The yields of reducing sugars of all the experiments were calculated using the Somogyi-Nelson method. Enzymatic hydrolysis was proven to be the most effective using the combination of both of the enzymes for a period of 96 hours at pH = 4.5 and temperature 45 °C. Yield of the reducing sugars under these conditions reached 27,4241 ± 0,0007 gl-1.
Study of growth and optimization of selected metabolites production by Zymomonas mobilis
Lukačková, Adéla ; Vránová, Dana (referee) ; Babák, Libor (advisor)
In the diploma thesis are discussed the process of enzymatic hydrolysis of waste paper as a source for the production of bioethanol by bacteria Zymomonas mobilis. In the theoretical part summarize basic information about particular methods of hydrolysis, about paper used as a raw material for enzymatic hydrolysis, about possibilities of the fermentative production of bioethanol focusing on the method of simultaneous saccharification and fermentation comparison with enzymatic hydrolysis and fermentation. Suitable microorganisms for ethanolic fermentation and simultaneous saccharification and fermentation and their advantages and disadvantages, are further discussed in this part as well. The theoretical part ends with the suggestion of the technological process for production of bioetanol. It covers all necessary steps from the input of raw material to the separation of produced ethanol. In the experimental part various parameters of hydrolysis, fermentation and simultaneous saccharification and fermentation were optimized using enzymes from Novozymes® company and the Zymomonas mobilis CCM2770 and Zymomonas mobilis LMG457 bacterium. The conversion rate of paper cellulose to gluckose and production of ethanol were observed by HPLC/RI method. Type of buffer, quantity of cells, enzyme and substrate were optimized in order to maximize the efficiency of the process. All experiments were performed on paper containing high amount of cellulose and for comparison on standard medium which contains gluckose. The highest yields was achieved with the use of Novozymes® Cellulosic ethanol enzyme Kit. The strain Zymomonas mobilis LMG457 has demonstrated as a better producer.

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