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Raman spectrometry of pigments of cyanobacteria, algae and lichens in the astrobiology context
Kovács, Michal ; Jehlička, Jan (advisor) ; Osterrothová, Kateřina (referee)
This work deals with the possibility of Raman spectroscopical identification of selected biomarkers of extremophile species. It focuses mainly on selected cyanobacteria, algae and lichens with an emphasis on the ability to detect carotenoids. These pigments exhibit three characteristic bands of Raman spectra which represent stretching vibrations C=C; C-C and bending vibration C-CH3 in molecules of carotenoids. Raman spectra were measured not only by laboratory microspectrometers (λ - 514 nm and 532 nm), but also by portable and handheld spectrometers (λ - 532 nm, 785 nm and 700 - 1100 nm). In the case of cyanobacteria, the spectroscopical analysis was performed also on the fractions obtained by high performance liquid chromatography (HPLC). This work critically evaluates the possibilities of Raman spectroscopy to identify the carotenoids of cyanobacteria, algae and lichens. Besides the signal of carotenoids, interpretation of other bands in the Raman spectra corresponding to the presence of other biomarkers is given here for selected samples. The obtained Raman spectra of carotenoids should be interpreted with great caution, because of the ifluence of several factors, which potentially cause unsystematic shifts in the positions of Raman bands (carotenoids bond in biological tissue, interactions with...
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Raman spectrometry of carotenoids of selected microorganisms
Novotná, Julie ; Jehlička, Jan (advisor) ; Machovič, Vladimír (referee)
In this thesis Raman spectroscopy is evaluated as a tool of identification and discrimination of carotenoids from microbial biomass. Microorganisms, halophilic or nonhalophilic, belong to Cyanobacteria, Proteobacteria, Chlorophyta, Rhodophyta and to others. Biomass was cultiveted under laboratory conditions and yielded varied colours. Raman spectra were recorded succesfully from lyophilized biomass by excitation wavelenth 514.5 nm (dispersive Raman microspectrometr) and 1064 nm (FT Raman spectrometer). Results were compared with Raman spectroscopic data from pigment extracts. Spectra of carotenoids are characterized by the main Raman bands υ1, υ2 a υ3 due to C=C stretching, C-C stretching and C-CH3 deformation. HPLC/UV-VIS allows effective pigment separation from extracts and detection of separated pigments by UV-VIS analyzator. Assessment of Raman analysis and its potential to detect microbial carotenoids are discused. Sarcinaxantin is an unusual carotenoid identified together with more common β - carotene. Raman spectroscopic results obtained on carotenoids recorded from colonies which accumulated more than one carotenoid need to be interpreted carefully. Powered by TCPDF (www.tcpdf.org)
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Detection of nitrogen containing biomarkers using portable Raman spectrometers - use in exobiology
Schneedörfler, Rudolf ; Jehlička, Jan (advisor) ; Machovič, Vladimír (referee)
This thesis was focused on testing of portable Raman spectrometer for detection of components in model mixtures of five different biomolecules in a gypsum matrix. The main goal was to test the ability of the instrument to detect amino acids glycine, L-proline, L-alanine and nucleobase thymine in samples containing UV protective pigment -carotene. Other measurements were taken using the laboratory inVia Reflex instrument to comapare the results gained from the portable Raman spectrometer. Both instruments were equipped with the excitation laser working at 785 nm wavelength. It was found out that it is possible to detect amino acid in mixtures containing -carotene at the lowest concentration of amino acid 100 g/kg and the maximum concentration of -carotene 1 g/kg. Thymine could be identified at the concentration of 100 g/kg in mixtures with higher concentration of -carotene (10 g/kg). In mixtures of -carotene at the concentration of 1 g/kg and only one of the studied nitrogen containg compounds (at the concentration of 100 g/kg) in the gypsum matrix, it was possible to detect all present components. In mixtures containing two nitrogen compounds with -carotene at the concentration of 1 g/kg in the gypsum matrix, both nitrogenous compounds could be detected. When measuring the samples of the three nitrogen...
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Estimation of Raman spectrometric instruments (785 nm excitation) for detection of dark minerals
Šimon, Jan ; Jehlička, Jan (advisor) ; Machovič, Vladimír (referee)
Summary: Raman spectroscopy is a widely used method in geoscience fields. Using a portable Raman spectrometer is possible to identify different materials, Raman spectrometer will participate in the survey the Martian surface. Its use is widely applied in mineralogy. There was measured a set of dark, green and some bright minerals of different mineralogical system groups that have been assessed the applicability of the chosen detector excitation at 785 nm mainly off-road equipment. The obtained spectra were measured off-road equipment ahura and delta nu at excitation 785 nm and laboratory equipment InVia Renishaw and there were used lasers at excitaion of 785 nm and 514 nm. It was set of these minerals: Prehnite, Sulphur, Tyrkenit (howlit), Pyroxene (diopside), Libethenite, Toutmaline (verdelite), Dioptas, Klinoklas, Langit, Jadeit, Pseudomalachit (ehlit), Actinolite, Epidote, Augite. Some minerals were measured off-road equipment acquired spectrum, witch corresponded with laboratory measurements, the spectra of other optical properties due to their ambiguous. Keywords: Raman spektroscopy, portable Raman spectrometer, mineralogy, dark and green minerals
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Raman spectormetry in Art
Minaříková, Laura ; Jehlička, Jan (advisor) ; Osterrothová, Kateřina (referee)
This thesis deals with the use of Raman spectroscopy in the arts, specifically in the identification of precious stones and semi-precious stones in various art works. This work describes the basics of this method, options and practical use based on selected scientific publications. The existing results of research in recent years shows that this spectroscopic analytical method on the rise. It is thanks to the many advantages that this method offers skilled in the art. The main advantages of Raman spectroscopy include speed and affordability analysis, minimal or no sample preparation, and most importantly - non-destructive to sample and explore the possibility of sample on the spot, without having to often very difficult transport to the laboratory. Key words Raman spectrometry, art, characterization of artifacts
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Anthracological analysis of chernozems in Czechia
Danková, Lenka ; Zádorová, Tereza (referee) ; Šefrna, Luděk (advisor)
This thesis deals with a pedogenesis of chernozems in Czechia (Central Europe). It solves a problem with open landscapes in Central Europe, further a role of man and fires in formation of this soils and relation between colour of chernozems and the content of black carbon. In my thesis is represented pedoanthracology as a method, which can be useful for future study of open landscapes in Central Europe and for an influence of man. In this thesis, there were also analysed two chernozemic soils with Raman spektrometry. It was found out, that chernozems was probably formed under forest-steppe vegetation with residue of post glacial steppe. Anthropogenic activity and fires could be new factors of pedogenesis of Central European chernozems. It was showed a strong relation between colour and content of BC. Raman spectrometry found a presence of BC in our analysed soils.
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Possibilities of Raman spectrometry application by Fire Brigade Units
Mičánková, Helena ; Osvald, Josef (referee) ; Čáslavský, Josef (advisor)
Thesis is focused on the application of Raman’s spectometer Ahura First Defender in cooperation with Fire Department. Theoretical part describes principles and development of Raman spectrometry and possibilities of its application. Practical part focus on identification of unknow substances in case studies and interpretation of the results. Final part of thesis evaluates contribution of Raman spectrometry for fast indentification of unknow compounds for Fire Rescue Brigade in the Czech Republic.
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