National Repository of Grey Literature 6 records found  Search took 0.01 seconds. 
Aronia – the source of bioactive compounds
Štumarová, Klára ; Vespalcová, Milena (referee) ; Veselá, Mária (advisor)
The aim of this bachelor thesis is to research the possible antimicrobial activity of aqueous and ethanolic extracts of aronia berries and tea mixture containing aronia. Also, the antioxidant activity and the concentration of the biologically active substances - polyphenols, flavonoids and anthocyanins was determined. Theoretical part contains a summary of basic information about Aronia melanocarpa, chemical composition, use and health effects of substances contained in its fruits. The experimental part focuses on the antimicrobial activity of the extracts on microorganisms Bacillus subtilis, Serratia marcescens and Micrococcus luteus. Farther there is spectrophotometrical determination of antioxidant activity, polyphenolic compounds, flavonoids and anthocyanins. From the experiment results flow that the extracts have almost none antimicrobial ability except tea mixture extracted with hot water. This extract has inhibitory effect on M. luteus and growth supportive effect on B. subtilis. It has been found that aronia fruits and tea mixture are rich in polyphenols and flavonoids.
Bactericides in the environment: Occurrence of selected bactericides in wastewater and their impact on the aquatic environment
DUŠÁNKOVÁ, Monika
Bactericides are a group of chemically active substances that exhibit antimicrobial effects. Their ability to kill or inhibit the growth of unwanted microorganisms is widely used in industry and healthcare, but also in household. However, the widespread use of bactericides has resulted in the abundant occurrence of these substances in surface water and wastewater, which subsequently supports the development of antibiotic resistance. Specifically wastewater treatment plants (WWTP) significantly influence the entry of antibiotic resistance genes into the environment. This study aimed to determine the occurrence of bactericides in wastewater and surface water samples, sediments and sewage sludge using high-performance liquid chromatography hyphenated with mass spectrometry. The detected concentrations were used to evaluate removal efficiency and impact on the recipient. The positive removal efficiency was confirmed mainly for the group of quaternary ammonium compounds and some antibiotics. Clarithromycin achieved the highest removal efficiency. Although some monitored substances had a high removal efficiency at the WWTP, their final occurrence proved to affect the aquatic environment. Quaternary ammonium compounds were effectively removed from the wastewater. But mainly thanks to their properties, such as strong sorption to solid substances, i.e., sediments and sludge, they were concentrated in sewage sludge. Using sewage sludge on agricultural land can cause problems by retaining some monitored substances in soils or leaching them into the surface and groundwater. This work briefly described the fate of selected bactericides at the sewage treatment plant and the adjacent recipient. The possible risks of using bactericides and their entry into the environment were pointed out. Given the variety and quantity of bactericides and the severe consequences of their excessive use, this topic deserves wider attention.
Aronia – the source of bioactive compounds
Štumarová, Klára ; Vespalcová, Milena (referee) ; Veselá, Mária (advisor)
The aim of this bachelor thesis is to research the possible antimicrobial activity of aqueous and ethanolic extracts of aronia berries and tea mixture containing aronia. Also, the antioxidant activity and the concentration of the biologically active substances - polyphenols, flavonoids and anthocyanins was determined. Theoretical part contains a summary of basic information about Aronia melanocarpa, chemical composition, use and health effects of substances contained in its fruits. The experimental part focuses on the antimicrobial activity of the extracts on microorganisms Bacillus subtilis, Serratia marcescens and Micrococcus luteus. Farther there is spectrophotometrical determination of antioxidant activity, polyphenolic compounds, flavonoids and anthocyanins. From the experiment results flow that the extracts have almost none antimicrobial ability except tea mixture extracted with hot water. This extract has inhibitory effect on M. luteus and growth supportive effect on B. subtilis. It has been found that aronia fruits and tea mixture are rich in polyphenols and flavonoids.
Laboratory evaluation of activity of traditional Bolivian medicinal plants
Hladová, Alena ; Klouček, Pavel (advisor) ; Přemysl, Přemysl (referee)
Traditional medicine of indigenous cultures is based on the medicinal effects of local plants. Those people have been taught to use these plants throughout history and they employ them as their primary health care. This is supported by the fact that the natives do not have the financial resources to pay for medical care and at the same time it is also accompanied by poor availability of hospitals in areas where these cultures are located. This thesis covers laboratory verification of antimicrobial and antioxidant activity of Amazonian plants from south west Bolivia. This paper also summarizes the economic and political situation of the country together with the development of traditional medicine in the world and with the potential use of this medicine in pharmacy. Part of the work is devoted to the issue of ever-increasing antimicrobial resistance and the possible effects of free radicals in the human body. The experiment was performed by testing nine samples of imported dried plants in laboratory. To determine the antimicrobial properties a microdilution method was used and the antioxidant activity was verified with the ORAC method which is based on the elimination of free radicals. The microdilution method confirmed 80% of the MIC in the initial concentrations tested (1,024 mg/ml) in Satureja ovata plants against Staphylococcus aureus ATCC 33591 bacteria and Streptococcus pyogenes bacteria and in the plant Baccharis genistelloides against S. pyrogenes bacteria. The other samples have failed to provide the value of the minimum inhibitory concentrations. This can be attributed to several factors which are described in this thesis. In contrast the positive effect free radicals was confirmed in all samples. The highest efficacy showed Satureja ovata (1373,2 ug TE/mg extract). Writing this thesis was accompanied by a lack of information about the tested plants, both in terms of their botanical description and in terms of comparing the laboratory results obtained with the results of specialized studies. Therefore the results of the experiment were studied in comparison to traditional use of the tested plants that have been provided by Bolivian natives or their effects have been analyzed from the literature.
An antimicrobial activity of Stevia rebaudiana extracts
Mlatečková, Tereza ; Zemanová, Jana (referee) ; Vespalcová, Milena (advisor)
This master thesis is oriented on study antimicrobial effects extracts and macerates from cure Stevia rebaudiana Bertoni. Teoretical part describes basic information about plant Stevia, summary of health significant matters contained in Stevia and posobilities preparing extracts from Stevia. Antimicrobial effects extracts and macerates from cure Stevia were testing on food-borne bacteria (Bacillus cereus and Micrococcus luteus) and yeasts (Geotrichum candidum and Hansenula anomala). Microorganism, extracts and macerates were chosen on basis previous study (Study of antimicrobial effects Stevia Rebaudiana extracts, Eva Rakovská). For screening antimicrobial activity were determined the growth curves by using turbidimetrie for bacteria and direct treetment metod of cells number for yeasts. Antimicrobial effects were confirmed aplication with diffusion pit method on the agar ranges. From the results flow the testing extracts and macerates from stevia analysed antimicrobial effects. The best effect was demostrated on macerates and the most sensitive was bacteria Micrococcus luteus with the best inhibitoring effects.
Vliv účinných látek z rostlin na bakterie mléčného kysání
Kousalová, Jitka
This dissertation deals with the influence of active substances from plants on lactic acid bacteria. It describes milk in terms of nutrition, sour milk products which can be made by means of using lactic acid bacteria, division and overview of lactic acid bacteria, substances contained in plants and the effects of four selected plants. The aim of this work was to determine the possibility of antimicrobial effects of caraway, cinnamon, sage and thyme on bacteria. The efficiency was performed on genus of Lactobacillus. The determination of change in inhibition was performed by disk diffusion method and determination of turbidity.

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