National Repository of Grey Literature 8 records found  Search took 0.00 seconds. 
A bioconversion study of cellulosic waste to ethanol using yeasts systems
Čalová, Iveta ; Vítová, Eva (referee) ; Babák, Libor (advisor)
This diploma thesis deals with the optimization of the production of ethanol from waste paper using yeast. There were used 4 kinds of paper as a substrate - office paper, non-recycled workbook, recycled workbook and newspaper. All papers were pretreated with the following procedures: grinding, microwaves + NaOH, microwave + H2SO4 and microwave + H2SO4 + NaOH. The glucose concentration was determined in enzymatic hydrolysis by HPLC. Saccharomyces cerevisiae were chosen for ethanol production. The production of ethanol was carried out with all the pretreated papers in simultaneous saccharification and fermentation. During hydrolysis, the pretreated papers have reached the highest results in the combination with microwave + H2SO4 + NaOH. Non-recycled workbook was the only exception, where the highest concentration of glucose has been obtained by the pretreatment of microwaves + H2SO4. Following results have been acquired: office paper 24,69 gdm-3, non-recycled workbook 22,47 gdm-3, recycled workbook 16,94 gdm-3 and newspapers 15,36 gdm-3. SSF was carried out again with all the papers and their pretreatments. The highest concentration of ethanol has been achieved in microwave pretreatment + H2SO4 + NaOH. The highest overall concentration has been gained from the office paper, amounted to 16,98 gdm-3. The maximum concentration of ethanol for non-recycled workbook has been 15,25 gdm-3, for recycled workbook 12,2 gdm-3 and for newspapers 12,59 gdm-3.
Detoxification of lignocellulose hydrolyzates
Vašíčková, Monika ; Pořízka, Jaromír (referee) ; Obruča, Stanislav (advisor)
The aim of this work was study of the detoxification of lignocellulose material hydrolysates and to investigate sawdust suitability as a substrate for microbial production of PHA by bacteria Burkholderia cepacia and Burkholderia sacchari. In the experimental part of the work the most suitable way of detoxification of model and real hydrolysate was studied. After that, detoxification methods used were evaluated. Criteria for evaluation were concentration of polyphenols as the most important microbial inhibitors and reduction saccharides as the main carbon substrate. Furthermore, fermentability of the hydrolysates was also tested by cultivation of two bacteria capable of PHA accumulation. Burkholderia sacchari demonstrated higher ability to accumulate PHA then Burkholderia cepacia. Then in the summary – most effective way for detoxification was ‚overliming‘. Major increase of PHB in biomass was obtained when Burkholderia sacchari was cultivated on media gained by application of overliming of real lignocellulose hydrolysate. However, total gains of PHB were more likely low and then sawdust can not be considered as a substrate for PHB production at industrial scale.
Optimization of bioethanol production by Zymomonas mobilis
Andrlová, Kateřina ; Vítová, Eva (referee) ; Babák, Libor (advisor)
Diploma thesis deals with use of Zymomonas mobilis for the production of bioethanol from waste paper. There were used three kinds of substrate (cardboard, drawing and office paper) to optimize of bioethanol production. Individual papers were subjected to the same pre treatment, namely a milling, a combination of microwave irradiation and NaOH, a combination of microwave irradiation and H2SO4 and combination microwave irradiation, H2SO4 and NaOH. The substrates were decomposed by enzymatic hydrolysis after pre treatment to evaluate the best pre-treatment. Simultaneous saccharification and fermentation was carried out for each substrate (with two of the best pre-treatment). The samples were taken during the hydrolysis and the simultaneous saccharification and fermentation, and were determined by HPLC. Growth curves of Zymomonas mobilis were constructed, as the most appropriate for SSF was chosen temperature of 40 ° C in which the exponential phase took place at the time of 6 15 hours. During hydrolysis was monitored glucose concentration in the solution. The maximum concentration of glucose was in the cardboard (microwaves + H2SO4 + NaOH) 16.46 gdm-3, a drawing (microwaves + H2SO4 + NaOH) 31.78 gdm-3, and office paper (microwaves + H2SO4) 25.04 gdm-3. The concentration of ethanol for SSF was highest in the same cases as in the hydrolysis. The cardboard was the maximum concentration of bio ethanol 9.5 gdm-3, for the drawing 16.1 gdm-3 and for the office paper 12.13 gdm-3.
Use of Kluyveromyces marxianus to bioethanol produce from waste paper
Tomečková, Andrea ; Hrstka, Miroslav (referee) ; Babák, Libor (advisor)
The diploma thesis is focused on production possibilities of bioethanol from waste paper by yeast Kluyveromyces marxianus. Waste cardboard was used as a potential substrate for bioethanol production. Several methods for cardboard preparation were introduced and compared as well as methods of fermentation. Simultaneous sacharification and fermentation and separate hydrolysis and fermentation of preprepared cardboard paper were performed in different pH buffer (4,8-7). Simultaneous sacharification and fermentation was held at a temperature of 45°C. Hydrolysis in separate hydrolysis and fermentation was performed at 50°C and fermentation at 25°C. Procedures outputs were obtained by sampling in specific time intervals and samples were analyzed by HPLC for presence and concentration glucose and ethanol. The results of the analysis have shown that the highest concentration of glucose produced by enzymatic hydrolysis was achieved by using microwaves, 2% H2SO4 and 2% NaOH pretreated paperboard at pH 4,8. The highest yield of ethanol was obtained by separate hydrolysis and fermentation of pulp pretreated by microwaves, 2% H2SO4 and 2% NaOH in pH 5,4 buffer. The method SHF proved to be more effective for the production of ethanol than SSF.
Detoxification of lignocellulose hydrolyzates
Vašíčková, Monika ; Pořízka, Jaromír (referee) ; Obruča, Stanislav (advisor)
The aim of this work was study of the detoxification of lignocellulose material hydrolysates and to investigate sawdust suitability as a substrate for microbial production of PHA by bacteria Burkholderia cepacia and Burkholderia sacchari. In the experimental part of the work the most suitable way of detoxification of model and real hydrolysate was studied. After that, detoxification methods used were evaluated. Criteria for evaluation were concentration of polyphenols as the most important microbial inhibitors and reduction saccharides as the main carbon substrate. Furthermore, fermentability of the hydrolysates was also tested by cultivation of two bacteria capable of PHA accumulation. Burkholderia sacchari demonstrated higher ability to accumulate PHA then Burkholderia cepacia. Then in the summary – most effective way for detoxification was ‚overliming‘. Major increase of PHB in biomass was obtained when Burkholderia sacchari was cultivated on media gained by application of overliming of real lignocellulose hydrolysate. However, total gains of PHB were more likely low and then sawdust can not be considered as a substrate for PHB production at industrial scale.
A bioconversion study of cellulosic waste to ethanol using yeasts systems
Čalová, Iveta ; Vítová, Eva (referee) ; Babák, Libor (advisor)
This diploma thesis deals with the optimization of the production of ethanol from waste paper using yeast. There were used 4 kinds of paper as a substrate - office paper, non-recycled workbook, recycled workbook and newspaper. All papers were pretreated with the following procedures: grinding, microwaves + NaOH, microwave + H2SO4 and microwave + H2SO4 + NaOH. The glucose concentration was determined in enzymatic hydrolysis by HPLC. Saccharomyces cerevisiae were chosen for ethanol production. The production of ethanol was carried out with all the pretreated papers in simultaneous saccharification and fermentation. During hydrolysis, the pretreated papers have reached the highest results in the combination with microwave + H2SO4 + NaOH. Non-recycled workbook was the only exception, where the highest concentration of glucose has been obtained by the pretreatment of microwaves + H2SO4. Following results have been acquired: office paper 24,69 gdm-3, non-recycled workbook 22,47 gdm-3, recycled workbook 16,94 gdm-3 and newspapers 15,36 gdm-3. SSF was carried out again with all the papers and their pretreatments. The highest concentration of ethanol has been achieved in microwave pretreatment + H2SO4 + NaOH. The highest overall concentration has been gained from the office paper, amounted to 16,98 gdm-3. The maximum concentration of ethanol for non-recycled workbook has been 15,25 gdm-3, for recycled workbook 12,2 gdm-3 and for newspapers 12,59 gdm-3.
Use of Kluyveromyces marxianus to bioethanol produce from waste paper
Tomečková, Andrea ; Hrstka, Miroslav (referee) ; Babák, Libor (advisor)
The diploma thesis is focused on production possibilities of bioethanol from waste paper by yeast Kluyveromyces marxianus. Waste cardboard was used as a potential substrate for bioethanol production. Several methods for cardboard preparation were introduced and compared as well as methods of fermentation. Simultaneous sacharification and fermentation and separate hydrolysis and fermentation of preprepared cardboard paper were performed in different pH buffer (4,8-7). Simultaneous sacharification and fermentation was held at a temperature of 45°C. Hydrolysis in separate hydrolysis and fermentation was performed at 50°C and fermentation at 25°C. Procedures outputs were obtained by sampling in specific time intervals and samples were analyzed by HPLC for presence and concentration glucose and ethanol. The results of the analysis have shown that the highest concentration of glucose produced by enzymatic hydrolysis was achieved by using microwaves, 2% H2SO4 and 2% NaOH pretreated paperboard at pH 4,8. The highest yield of ethanol was obtained by separate hydrolysis and fermentation of pulp pretreated by microwaves, 2% H2SO4 and 2% NaOH in pH 5,4 buffer. The method SHF proved to be more effective for the production of ethanol than SSF.
Optimization of bioethanol production by Zymomonas mobilis
Andrlová, Kateřina ; Vítová, Eva (referee) ; Babák, Libor (advisor)
Diploma thesis deals with use of Zymomonas mobilis for the production of bioethanol from waste paper. There were used three kinds of substrate (cardboard, drawing and office paper) to optimize of bioethanol production. Individual papers were subjected to the same pre treatment, namely a milling, a combination of microwave irradiation and NaOH, a combination of microwave irradiation and H2SO4 and combination microwave irradiation, H2SO4 and NaOH. The substrates were decomposed by enzymatic hydrolysis after pre treatment to evaluate the best pre-treatment. Simultaneous saccharification and fermentation was carried out for each substrate (with two of the best pre-treatment). The samples were taken during the hydrolysis and the simultaneous saccharification and fermentation, and were determined by HPLC. Growth curves of Zymomonas mobilis were constructed, as the most appropriate for SSF was chosen temperature of 40 ° C in which the exponential phase took place at the time of 6 15 hours. During hydrolysis was monitored glucose concentration in the solution. The maximum concentration of glucose was in the cardboard (microwaves + H2SO4 + NaOH) 16.46 gdm-3, a drawing (microwaves + H2SO4 + NaOH) 31.78 gdm-3, and office paper (microwaves + H2SO4) 25.04 gdm-3. The concentration of ethanol for SSF was highest in the same cases as in the hydrolysis. The cardboard was the maximum concentration of bio ethanol 9.5 gdm-3, for the drawing 16.1 gdm-3 and for the office paper 12.13 gdm-3.

Interested in being notified about new results for this query?
Subscribe to the RSS feed.