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Production of carotenoids by red yeasts grown on some waste substrates
Kubáčková, Martina ; Čarnecká, Martina (referee) ; Márová, Ivana (advisor)
Carotenoids belong to the most widespread and abundant classes of natural pigments with utilised in food industry, pharmacy and cosmetics. Presented work was realized as a comparative study of some substrates for cultivation of red yeast Rhodotorula glutinis, which produces carotenoid pigments. Yeasts were cultivated in different media with several waste substrates (for example potato fiber, apple waste, cereals, grains, etc.) as nutrition sources. To some substrates hydrolytic enzymes isolated from the fungi genus Fusarium were added. Majority of waste substrates were acceptable for cultivation. However, the best conditions for production of carotenoid enriched biomass (6,4 g/l of biomass enriched 3,2 mg /g of beta-carotene) exhibited media with hydrolytic fungal enzymes.
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Controlled prodution of pullulan by yeast-like organism Aureobasidium pulluans
Skoumalová, Petra ; Obruča, Stanislav (referee) ; Márová, Ivana (advisor)
Bachelor's thesis is focused on study of influence of exogenous stress factors on biomass and pullulan production by microorganism Aureobasidium pullulans. As a part of this work an overview of stress factors, pullulan producers, its structure, function and technological use was introduced. In the experimental part growth characteristics of Aureobasidium pullulans and pullulan production during growth in optimum conditions and under stress were analyzed. The reduced availability of oxygen resulted in a decrease of biomass production accompanied by increased pullulan production. Chemical stress induced by NaCl significantly affected mainly biomass production. The highest production of pullulan was found at 15 g / l of NaCl. Ethanol stress exhibited growth inhibition and at higher concentration also lack of pullulan production. Peroxid stress exhibited no effect on pullulan production. Short-time exposure to low heavy metal concentration (Se(IV), Cr(III)) influenced pullulan production more positively than long-term effect.
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Changes of the content of some active substances in aplle and pear fruits during storage
Matějková, Markéta ; Halienová, Andrea (referee) ; Márová, Ivana (advisor)
In presented bachelor thesis low molecular substances antioxidants found in plant food were described. Antioxidants from apples and pears were studied in detail, particularly their changes during storage in different conditions. Fruit species were described more closely in this study. The theoretical part is focused on ripening and storage of the fruits. The most common diseases of apples and pears are introduced too. In the practical part changes of some antioxidant levels in apples Idared (red-yellow) and Golden Delicious (green-yellow) were analyzed. Apples were stored for 2 months in three various storage conditions – at standard ambient temperature in the lab, in cellar and in refrigerator. In regular intervals samples were taken and levels of low molecular antioxidants (vitamin C, total phenolics, total flavonoids) and total antioxidant activity in apple fruits were analysed and compared. A surface microflora of the apples was analysed during the whole storage time. The most suitable storage conditions exhibited cellar (9 °C, 38,4 %). Phenolic changes in apples were substantially lower than flavonoid changes, while ascorbate content decreased dramatically with the storage time. Antioxidant activity was related mainly to ascorbate levels, influence of flavonoid changes was observed too. Antioxidant parameters were analyzed also in pear fruits, whose were stored only for very short time.
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Analysis of biologically active substances in some cereal products
Valentová, Radka ; Starečková, Terezie (referee) ; Márová, Ivana (advisor)
Presented bachelor thesis is focused on study of biologically active substances in cereal products. In theoretical part over view of cereal active substances, predominantly phenolic compounds were introduced. In practical part 15 kinds of cereal products were analyzed. In these materials some group parameters - total phenolics, total flavonoids and total antioxidant activity were measured by spectrophotometry. RP-HPLC/UV-VIS method was performed for analysis of selected individual flavonids. The highest content of phenolic compounds was measured in cereals containing fruits (raspberries, blueberries, tropical and red fruit), cacao, crusty fruits (hazel nuts, sunflower seeds) and buckwheat. All cereal products contain catechine, epicatechine, catechin gallate, epicatechin gallate, chlorogenic and ferulic acid. As a part of bachelor thesis simple sensory analysis was performed and consumer questionnaires were evaluated.
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Comparison of PCR methods suitable for identifikation of yeasts in foodstuffs.
Zovčáková, Monika ; Márová, Ivana (referee) ; Vránová, Dana (advisor)
This bachelor´s thesis deals with identification of yeasts by PCR method in foods. It includes basic information about yeast´s cell. There are elaborated molecular methods of yeast identification. Yeasts are crucial agents in many important natural and industrial bioprocesses as well as in spoilage of foods. Classical methods include morphological and biochemical tests, which are time consuming. The rapid detection and identification of yeasts is necessary for assessment of their beneficial and harmful roles in the production and spoilage of foods.
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Regulation of production of enriched biomass and lipidic substances in carotenogenic yeasts.
Němcová, Andrea ; Ondruška, Vladimír (referee) ; Márová, Ivana (advisor)
Carotenoids belong to the most abundant classes of natural pigments with important biological functions. In last years intensive studies focused on biotechnological production of carotenoids by suitable microorganisms were done. Presented work was realized as a comparative study of three yeast strains: Rhodotorula glutinis, Rhodotorula rubra a Sporobolomyces roseus. These strains were cultivated in different media with several waste substrates (potato extract, whey) as nutrition sources. Additionally, strains were exposed to some types of exogenous stress. All strains were able to use tested waste substrates as nutrition sources. Most of strains exhibited increased carotenoid production, in several conditions accompanied by high biomass formation. As the best producer of enriched biomass yeast strain Rhodotorula glutinis CCY 20-2-26 cultivated on medium with addition of lyophilized whey (9 g/l of biomass enriched by 2 mg/g of beta-carotene) and/or under mild salt stress.
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Influence of storage conditions on content of biologically active substances in apple fruits.
Ferdová, Jitka ; Čarnecká, Martina (referee) ; Márová, Ivana (advisor)
This study deals with antioxidants in diet and their effects on human organism. Further, it summarizes the agents affect the quality of apples in the course of long-term storage and it outlines the possibility of defence against them. In the experimental part methods of determination of antioxidant enzymes superoxid dismutase (SOD), catalase and polyphenol oxidace (PPO) in apples were introduced. The enzymes were measured in apples tissues in liquid nitrogen after 158 days in normal or modified atmosphere. In Apple the quantitative and qualitative analysis of proteins was realized. Further, some low molecular antioxidants (total phenolics, total flavonoids and vitamin C) as well as total antioxidant status were measured in frozen raw juice. This values were compared with values from apples analyzed immediately after the harvesting. Artificial inoculation with fungi was made in the last part and the fruitfulness was observed.
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Biologically significant substances in cereal products
Vondráčková, Hedvika ; Halienová, Andrea (referee) ; Márová, Ivana (advisor)
Presented work was focused on study of biologically significant substances in cereal products. In experimental part selected active substances in cereal bars were analyzed. The highest content of total phenolics, total flavonoids, total antioxidant capacity, procyanidin B2 and chlorogenic acid was measured in plums and blueberry bars. The highest level of reduced saccharides was evaluated in raspberry and cereal bars. Presence of main simple sugars - maltose, glucose and fructose was detected in all bar samples.
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Degradation of biomaterials in model physiological conditions
Mikulíková, Zuzana ; Obruča, Stanislav (referee) ; Márová, Ivana (advisor)
The aim of presented work was to study degradation of selected modified protein materials and optimization of methods usable for protein concentration changes in samples that undergo proteolytic degradation. In first part overview of biomaterials used in medicine applications, biocompatibility and of collagen materials and their applications was given. In experimental part some methods for proteolysis determination were tested using standards of albumin, collagen and selected amino acids. As a part of this work proteolysis of selected modified collagen materials was observed. First, following methods for total protein analysis were tested: ninhydrin method, biuret method, Hartree-Lowry, UV-VIS spectrophotometry and TNBS method (trinitro-benzen-sulphonic acid). For collagen proteolysis determination two of these methods were optimized: biuret method (peptide group detection) and TNBS (primary amino group detection). These two methods were applied on enzyme degradation of three collagen samples: soluble collagen standard, collagen standard type I (insoluble) and modified collagen material for clinical application. In soluble and modified collagens collagenase effect exhibited decrease of peptide bounds and, simultaneously, increase of primary amino groups according to enzyme concentration and enzyme:substrate ratio. In insoluble collagen analysis was strongly influenced by structure and conformation changes of material during degradation.
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The relationship between kidney stone formation and the composition of food.
Zbořilová, Eliška ; Márová, Ivana (referee) ; Vránová, Dana (advisor)
This bachelor’s thesis deals with causes of formation and identification of urinary concrements. The theoretical part of this study includes basic definition of problems with urolithiasis, points to risk factors of formation of urinary concrements and deals with their classification in accordance to their chemical composition. Important part of this study has been devoted to dietary habits, because composition of ingested food and daily intake of liquids is very important for formation of concrement in urinary tract. Analysis of urinal concrement and following identification of its composition is absolutely unavoidable for definition of subsequent therapeutic method of treatment of urolithiasis. In the experimental part, infrared spectroscopy has been used for analysis of urinal concrements. The calibration lines of the most frequent two-component mixtures of urinary concrements have been scaled by this method
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