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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.
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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.
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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).
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Alcohol Yield of Oat, Barley and Wheat Hydrolysates
PIKL, Miroslav
Major part of ethanol production for industrial use in Czech Republic is made from cereals. Effect of acid, alkali and enzymatic hydrolysis after thermopressure preparation takes part in the paper. The most promising alternative is enzymatic hydrolysis. Especially efficiency of different hydrolytic enzymes towards different species of cereals takes the main part of the simulations. Local farm products, oats, barley and wheat were prepaired by steam explosion in different pressure. After hydrolysis were detected the GE and after fermentation was observed the production of alcohol.
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