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Production, characterization and application of polymers of malic and glutamic acids
Čangelová, Katarína ; Kučera, Dan (referee) ; Obruča, Stanislav (advisor)
Subject of this bachelor thesis was study of biopolymers production using microorganisms. Polymer of malic acid was produced by Aureobasidium pullulans, a yeast-like fungus. Biosynthesis of polymer of glutamic acid was carried out by Bacillus licheniformis bacterium. Particular polymers, their microbial producers and possible application in different areas are characterised in the theoretical part of the thesis. Through experiments, the effect of various conditions on cell growth and production of these polymers was studied. Cultivation conditions were optimised in terms of polymers production. Subsequently, waste substrates - whey and poultry feathers were used. Microbially-produced polymer of malic acid was hydrolysed with 2 M sulfuric acid. Concentration of malic acid was analysed by IEC with a conductivity detector. Concentration of polymer of glutamic acid was determined by a spectrophotometric method using CTAB.
Production and characteritzation of extracellular hydrolases from selected moulds
Skoumalová, Petra ; Čarnecká, Martina (referee) ; Márová, Ivana (advisor)
This diploma thesis is focused on study of potential production of extracellular hydrolytic enzymes. The theoretical part deals with characterization of selected hydrolytic enzymes, their catalytic properties, the possibility of extracellular hydrolase production by fungi and their applications. In experimental part production strains Aureobasidium pullulans, Fusarium solani and Phanerochaete chrysosporium were used. Productions of cellulase, amylase, xylanase, lipase, protease and lignin-degraded enzymes (laccase, manganese- dependent peroxidase, lignin peroxidase) were observed. Cultivations were carried out in submersed mode in mineral medium supplemented by waste co-substrates such as wheat bran, corn bran, rice bran and oat bran, sawdust, rice, apple fiber, egg pasta and egg-free pasta. Production of enzymes depended on the substrate type and time of cultivation. The highest cellulase, xylanase and amylase activities were measured in the first period of cultivation (3 to 7 day). Lignin-degraded enzymes and proteases were produced at the end of cultivation (7 to 10 days). Lipolytic activity was detected only in A. pullulans, where the activity increased with time of cultivation. The highest value was determined during cultivation on wheat bran (3.6 nmol/ml.min). The highest xylanase and celulase activity (170.3 nmol/ml.min, 248.0 nmol/ml.min) were determined during cultivation of F. solani on corn bran. The highest amylase activity (111.8 nmol/ml.min) was reported in P. chrysosporium during the cultivation on rice. The highest protease activity (68.0 nmol/ml.min) was determined in F. solani grown on wheat bran. The best producer of laccase was A. pullulans, the highest production was recorded for egg-free pasta (27.0 nmol/ml.min). The maximum lignin peroxidase activity (12.5 nmol/ml.min) was measured during the cultivation of F. solani on egg pasta, while the highest yield of Mn-dependent peroxidase (7.7 nmol/ml.min) was achieved during the cultivation of A. pullulans on wheat bran. Lignin-degraded enzymes behaved as inductive, while the other enzymes were produced in mineral medium too. Activity of cellulase in the mineral medium was in A. pullulans strain higher than in media with waste substrates. Enzymes produced into A. pullulans medium were purified by ultrafiltration, ion exchange chromatography and gel filtration.
Production, characterization and application of polymers of malic and glutamic acids
Čangelová, Katarína ; Kučera, Dan (referee) ; Obruča, Stanislav (advisor)
Subject of this bachelor thesis was study of biopolymers production using microorganisms. Polymer of malic acid was produced by Aureobasidium pullulans, a yeast-like fungus. Biosynthesis of polymer of glutamic acid was carried out by Bacillus licheniformis bacterium. Particular polymers, their microbial producers and possible application in different areas are characterised in the theoretical part of the thesis. Through experiments, the effect of various conditions on cell growth and production of these polymers was studied. Cultivation conditions were optimised in terms of polymers production. Subsequently, waste substrates - whey and poultry feathers were used. Microbially-produced polymer of malic acid was hydrolysed with 2 M sulfuric acid. Concentration of malic acid was analysed by IEC with a conductivity detector. Concentration of polymer of glutamic acid was determined by a spectrophotometric method using CTAB.
Raman spectroscopy as a tool for analysis of biotechnologically relevant microorganisms
Záhorská, Linda ; Enev, Vojtěch (referee) ; Mgr.Ota Samek, Ph.D. (advisor)
The diploma thesis deals with the study of biotechnologically significant microorganisms, using the Raman spectroscopy. Content of the theoretical part is brief characteristic of Raman spectroscopy as a method, its use in practice and also use as a tool for monitoring of biotechnologically processes. Thesis was further focus on the biotechnologically significant microorganism Aureobasidium pullulans, its use in biotechnology and also for over-produced substances and in particular poly-L-maleic acid and pullulan. The content of the experimental part was study of selected strains A. pullulans, specifically stains as DSMZ, CCM F148 and CCM 8182, using Raman spectroscopy on the various types of culture media. Subject of practical part research was too production of extracellular polymers, acid poly-L-apple and pullulan, by selected strains A. pullulans. Objective of my thesis was described and determinate, spectra of individual strains as well as extracellular products, mainly pullulan, and then choose suitable production medium and optimal production strain A. pullulans. During experimental work was found, that optimal production strain was DSMZ strain culture on the mineral medium with the addition of yeast autolysate, which was optimal medium type. The content of the pullulan produced was for gravimetric determination, 6,3g/L, which also confirmed the results of the HPLC method. It was experimentally found, that Raman spectroscopy isn´t suitable method for quantification of extracellular products, but is appropriate and was used for PCA analysis of individual strains.
Characetrization of selected microbial enzymes
Bradáčová, Kristína ; Hlaváček, Viliam (referee) ; Márová, Ivana (advisor)
This bachelor´s thesis is focused on controlled production and identification of extracellular microbial hydrolytic enzymes by fungi. Theoretical part deals with characterization of selected hydrolytic enzymes, their properties, possibility of production and application. In experimental part the production of enzymes by fungal strains Phanerochaete chrysosporium, Aureobasidium pullulans and Aspergillus oryzae was performed. Cultivation was conducted in submersed mode in mineral medium and in media with waste co-substrates such as wheat bran, sawdust, rapeseed cake (lipids content 2,55 %) and rapeseed cake rich in lipids (9 %). The activity of cellulases, xylanases, amylases, ligninperoxidase, manganese-dependent peroxidase and laccase was monitored during cultivation process and regularly on 3rd, 7th, 10th and 15th day of cultivation. Production of enzymes depended on time and the subsrate type. Cellulases and xylanases were produced mainly on 3rd and 7th day of cultivation, amylases on 3rd and 15th day and lignolytic enzymes on 7th and 15th day. Samples were further separated and analyzed by ultrafiltration, gel filtration and PAGE-SDS electroforesis.
Production of microbial enzymes and their stabilization by encapsulation
Hazuchová, Eva ; Němcová, Andrea (referee) ; Márová, Ivana (advisor)
The present thesis deals with the production of microbial enzymes and their subsequent stabilization through encapsulation. The theoretical part focuses on microbial enzymes, especially extracellular hydrolases, their producers and characteristics. Within the theory is also discussed the possibility of the application of enzymes in the field of pharmacy and medicine. Experimental work was focused on the actual production of microbial enzymes and methods for their to stabilization. The production of proteolytic and lipolytic enzymes in dependence on time and the used culture substrate were followed. The highest enzyme production was observed in Aspergillus oryzae when cultured on wheat bran at the third day of cultivation. In the experimental part was further carried out the identification, isolation and purification of enzymes. A substantial part of the experiment was to stabilize produced microbial enzymes by encapsulation. Enzymes were entrapped into alginate particles with encapsulation efficiency in the range of 55-70 %. The highest efficiency exhibited encapsulated enzymes from Aspergillus oryzae. Subsequently, long-term stability of the encapsulated enzyme in two environments (in water and gel) was followed during six weeks incomparison with free enzyme. During storage of free enzyme a significant decrease in enzyme activities occured, especially between the fourth and sixth week of storage. On the contrary, in encapsulated increased enzyme activities were observed. Empty particles exhibited higher stability during storage in the gel than in water. In this thesis potential use of enzymes in the pharmaceutical industry as agents promoting digestion was tested too. According to the results, particles with encapsulated microbial enzymes could be considered as suitable for some pharmaceutical applications.
Study of biodegradation of poly(hydroxy alkanoates).
Wurstová, Agáta ; Přikryl, Radek (referee) ; Obruča, Stanislav (advisor)
The master‘s thesis is focused on the study of biodegradation of polyhydroxyalkanoates, namely polymer polyhydroxybutyrate. The first part of the thesis is focused on the study of biodegradation of polyhydroxybutyrate in the form of crystalline granules of PHB and PHB films using selected species of microorganisms from bacteria, yeasts and fungi. As a representative of bacteria was chosen microorganism Delftia acidorovans, as yeast was selected Aureobasidium pullulans and Aspergillus fumigatus as fungi. PHB depolymerase activity was measured employing turbidemtiric method with suspension of PHB granules as substrate. The results showed that D. acidorovans can partially degrade PHB. On the contrary A. pullulans cannot effectively degrade PHB. The most significant degradation ability revealed A. fumigatus, which was able to degrade PHB completely. Extracellular enzymes excreted by these microorganisms when cultivated on PHB materials as sole carbon sources were analyzed by SDS-PAGE. The second part of the thesis deals with the biodegradation of PHB in the form of PHB film, PHB hardened foil and PHB Nanoul fabric using standard composting test. Semi-solid cultivation showed positive results. In the interval from 14 days to two months were all forms of the PHB completely biodegraded. With semi-solid cultivation was also studied biodegradation rate of the polyurethane elastomeric films which were modified by partial replacement of polyester polyol by PHB. The test samples were prepared using PHB from Sigma and the PHB samples prepared at the Faculty of chemistry VUT. Samples with different concentrations of the dispersed PHB (1 %, 5 % and 10 %) in the polyurethane were also object of the study. At the end of the cultivation (after 2 months) were measured mechanical properties in tension of the material, then efficiency of biodegradation by gravimetric analysis and modification of the material surface by microscopic analysis.
Production of extracellular polymeric substances by Aureobasidium pullulans
Horáček, Pavel ; Breierová, Emília (referee) ; Márová, Ivana (advisor)
The diploma thesis is focused on the study of the influence of cultivation conditions and arrangement for the production of extracellular polymeric substances by using yeast-like microorganism Aureobasidium pullulans. In the theoretical part a brief description of A. pullulans, its use in biotechnology and produced exobiopolymers, especially pullulan and poly-L-malic acid are presented. The first aim of the experimental part was to set the most appropriate cultivation conditions for A. pullulans CCM 8182. Growth and production properties in optimum conditions were compared with cultivation on waste substrates - oat bran, buckwheat husks, apple fiber and others. Waste substrates can be used as cheap nutrient sources which enable reducing cost of potential biotechnological production. As a further part of this work, optimization of HPLC/RI method for analysis of exobiopolymers has been done. Optimal mobile phase composition and chromatography conditions were proposed. Column Roa organic acid H+ was the most suitable for simultaneous separartion of glucose and malic acid. Before HPLC analysis hydrolysis of polymers was done. Sulphuric acid (5 mmol/L) was used as a mobile phase at flow rate 0.5 mL/min and temperature 60 °C. The highest production of pullulan occurred using oat bran as a substarate (13.03 g/L) at an initial pH 7.5. Maximum production of poly-L-malic acid was observed during the cultivation on apple peels (2.89 g/L) at pH 6. It was found that the higher production of poly-L-malic acid occurred at pH 6, while higher production of pullulan was at pH 7.5.
Production and characteritzation of extracellular hydrolases from selected moulds
Skoumalová, Petra ; Čarnecká, Martina (referee) ; Márová, Ivana (advisor)
This diploma thesis is focused on study of potential production of extracellular hydrolytic enzymes. The theoretical part deals with characterization of selected hydrolytic enzymes, their catalytic properties, the possibility of extracellular hydrolase production by fungi and their applications. In experimental part production strains Aureobasidium pullulans, Fusarium solani and Phanerochaete chrysosporium were used. Productions of cellulase, amylase, xylanase, lipase, protease and lignin-degraded enzymes (laccase, manganese- dependent peroxidase, lignin peroxidase) were observed. Cultivations were carried out in submersed mode in mineral medium supplemented by waste co-substrates such as wheat bran, corn bran, rice bran and oat bran, sawdust, rice, apple fiber, egg pasta and egg-free pasta. Production of enzymes depended on the substrate type and time of cultivation. The highest cellulase, xylanase and amylase activities were measured in the first period of cultivation (3 to 7 day). Lignin-degraded enzymes and proteases were produced at the end of cultivation (7 to 10 days). Lipolytic activity was detected only in A. pullulans, where the activity increased with time of cultivation. The highest value was determined during cultivation on wheat bran (3.6 nmol/ml.min). The highest xylanase and celulase activity (170.3 nmol/ml.min, 248.0 nmol/ml.min) were determined during cultivation of F. solani on corn bran. The highest amylase activity (111.8 nmol/ml.min) was reported in P. chrysosporium during the cultivation on rice. The highest protease activity (68.0 nmol/ml.min) was determined in F. solani grown on wheat bran. The best producer of laccase was A. pullulans, the highest production was recorded for egg-free pasta (27.0 nmol/ml.min). The maximum lignin peroxidase activity (12.5 nmol/ml.min) was measured during the cultivation of F. solani on egg pasta, while the highest yield of Mn-dependent peroxidase (7.7 nmol/ml.min) was achieved during the cultivation of A. pullulans on wheat bran. Lignin-degraded enzymes behaved as inductive, while the other enzymes were produced in mineral medium too. Activity of cellulase in the mineral medium was in A. pullulans strain higher than in media with waste substrates. Enzymes produced into A. pullulans medium were purified by ultrafiltration, ion exchange chromatography and gel filtration.
The study of production of hydrolytic enzymes for cellulose wastes treatment
Řezáčová, Barbora ; Flodrová, Dana (referee) ; Omelková, Jiřina (advisor)
The study of production of hydrolytic enzymes dealt with the production of cellulase and polygalacturonase by two microbial strains - Aspergillus niger and Aureobasidium pullulans. The enzymes were produced in solid-state fermentation system. The wheat straw and sugar beet pulp were used as a substrate. The substrates were moistened by water, mineral solution or by medium with glucose. The effect of mineral solution and glucose on production of these enzymes were monitored during cultivation. The highest production of polygalacturonase was achieved by Aspergillus niger during cultivation on sugar beet pulp moistened by mineral solution. The highest production of cellulase was achieved by Aspergillus niger during cultivation on wheat straw moistened by medium with glucose.

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