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Antioxidants from natural sources are extensively attaining consideration to avert the skin from damage and aging caused by free radicals. Flaxseed (Linum usitatissimum L.), a natural therapeutic agent, was meant to be explored cosmeceutical by quantifying its potential phytoconstituents and to be incorporated into a microemulgel for topical use. Hydroalcoholic fractions (both methanolic and ethanolic; 80%) flaxseed extracts were subjected to phytochemical screening by quantifying total phenolic content (TPC), total flavonoid content (TFC), and high-performance liquid chromatography-ultraviolet (HPLC-UV), and for biological activities through 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, tyrosinase inhibition assay, and sun protection factor (SPF). Ethanolic fraction was selected for further study by TPC (18.75 mg gallic acid equivalent/g) and TFC (1.34 mg quercetin equivalent/g). HPLC-UV analysis showed the existence of benzoic, quercetin, caffeic, vanillic, p-coumaric, gallic, cinnamic, syringic, and sinapic acids. Biological activities showed 87.00%, 72.00%, and 21.75 values for DPPH assay, tyrosinase inhibition, and SPF assays, respectively. An oil-in-water (OW) microemulsion containing the flaxseed extract, with 99.20 nm Zeta size, −19.3 Zeta potential and 0.434 polydispersity index was developed and incorporated in Carbopol-940 gel matrix to formulate an active microemulgel with 59.15% release in in vitro studies. The successfully formulated stable active microemulgel produced statistically significant effects (p < 0.05), in comparison to a placebo, on skin erythema, melanin, sebum, moisture, and elasticity, in a noninvasive in vivo study performed on 13 healthy human female volunteers. Other cosmeceutical products can also be formulated from flaxseed, making it a considerable candidate for further utilization in the pharmaceutical industry.

Pulses are an important crop for the human diet. The aim of this work was to characterize phenolic compounds (flavonoids and phenolic acids) in common Swedish dried pulses and to investigate the retention and distribution of phenolic compounds during hydrothermal treatment processes, including soaking, draining, and boiling. An ultrasound-assisted extraction method was optimized for flavonoid extraction. The phenolic compounds in the raw and cooked pulses, and the processing (soaking and boiling) water were analyzed using HPLC-UV/MS. Optimized extraction conditions for flavonoids were: 70 % methanol, pH 2, and sonication for 60 min. A total of 33 flavonoids and 6 phenolic acids were directly or tentatively identified and quantified. The profile of phenolic compounds largely depends on the pulse type with the total content ranging between 38-1860 mu g/g dry matter in the raw material. In most pulses, hydrothermal treatment led to a decrease of 50-85 % of total phenolic content, mainly due to leaching. The distribution of major phenolic compound subgroups in the soaking water, boiling water, and cooked pulse varied. The rate of retention of individual phenolic compounds depends possibly on both their structure and the pulse matrix.

Germination of chickpeas was carried out in the light using a closed germination chamber at 25 ± 2°C and 80% R.H. Calcium, zinc and selenium were sprayed throughout the germination period in concentrations of 25, 50, 75, and 100mg/L. HPLC-UV was used at 260nm to analyze the contents of isoflavones from the samples collected on 1st, 3rd, 5th, 7th and 9th day of germination. Profound increase in the content of biochanin A and fermonenetin was found on 7th day of germination in WM sample with 3.08 and 5.50 mg/g, respectively. Whereas, biochanin glucoside and genistein were acquired in maximum content of 4.34 and 2.41 mg/g in 5D25 and 9D25. The results proved the use of minerals at 25 and 50mg/L during germination to be ideal for increased isoflavone as well as for increased mineral contents. Significant increase of 0.98 g/mL, 1.27 g/g and 2.29 mL/g was observed for bulk density (BD), oil holding capacity (OHC) and water holding capacity (WHC), in a samples germinated for 5 days. The results of emulsifying activity (EA), foaming capacity (FC) and foaming stability (FS) significantly decreased from 44.22-36.48%, 27.82-12.63% and 16.34-8.00%, respectively. Current results of isoflavones, minerals and functional properties encourage the utilization of germinated chickpeas at industrial level for as a functional and nutritional ingredient for the germination period of 5 days at mineral supplementation of 25-50mg/L.

We report the dissipation behavior of pyrazosulfuron-ethyl under direct sunlight using iron-doped titanium dioxide nanoparticles (FeTiO2) as a catalyst. The test was carried out by reinforcement three varying aqueous pH solutions with pH~4.0,7.0 and 9.0 to make the homogeneous concentrations of T0 – untreated control, T1 – pyrazosulfuron-ethyl 70% WG @ 1 mg/L of pH water and T2 – pyrazosulfuron-ethyl 70% WG @ 2 mg/L of pH water. The fortified test samples were exposed to sunlight. The sampling occasions were 0, 1, 5, 10, 24, 48, 72 and 96th hours for all three different aqueous solutions having pH ~ 4.0 (acidic water), 7.0 (neutral water) and 9.0 (basic water). The acquired samples were quantified using validated high-pressure liquid chromatography with UV detection technique. The pyrazosulfuron-ethyl half-life (DT50) was calculated from the dissipation results by regression equation. The FeTiO2 nanoparticles were determined to be a wonderful decontaminating catalyst for pyrazosulfuron-ethyl in various water samples.

Cereals are a good source of phenolic acids, most of which are present in bound form. The aim of this study was to develop a method for quantifying total phenolic acids in cereals that includes a robust step for hydrolysis of bound forms. Different hydrolysis procedures were evaluated. Acid hydrolysis, even with subsequent use of enzymes, proved unsuitable for releasing bound phenolic acids from the cereal matrix. Base hydrolysis (3 M, 90 min) resulted in the highest extractability, with average recoveries of 88-108% for cereal phenolic acids. The phenolic acid content in cereals (two cultivars each of rye, barley, and oats, and eight cultivars of wheat) varied up to 2-fold between cereal genotypes and 1.5-fold within genotypes. The highest content was found in rye, followed by wheat, barley, and oats. Ferulic acid dominated in all cereals, amounting to 48-72% of total phenolic acid content.

In the current paper, the importance of determination of phenolic compounds in the instant coffee for the coffee’s quality evaluation was discussed. Particular attention was paid to the components of "natural" and "technological" origin such as ca?eoylquinic acids (CQA) and catechol (C) respectively. The conditions for the simultaneous determination of CQA and C in the instant coffee samples by the capillary zone electrophoresis (KZE) method were chosen. The separation of phenolic compounds was carried out in the borate buffer (40 mM, pH 9.5) with the voltage of +25 kV applied to the capillary inlet (60.5 (52) cm ? 50 ?m). The summary determination of the CQA isomers by the KZE method was proposed. The accuracy was estimated by spiked samples (the relative error was 4 %) and by comparison of the analysis results with the results obtained by an independent HPLC-UV method (the relative error was 7 %). To substantiate the "technological" nature of the catechol formation in the investigated product, the ground green and roasted coffee samples of varying roasting degrees, as well as instant coffee samples, were analyzed by the electrophoretic method. The CQA and C contents in the instant coffee samples were in the ranges of 9-55 and 0.40-0.85 mg / g, respectively. It was shown that increasing the coffee roasting degree leads to the decrease of CQA content and increase of C content in the ground roasted coffee samples. For the instant coffee samples, the inverse correlation between the CQA and C contents ( r calcul = 0.80; r tab = 0.40; n = 24), and the positive correlation between the C content and the roasting index ( r calcul = 0.68; r tab = 0.51; n = 15) were established. This combination of facts confirmed the "technological" nature of the studied compound formation., В данной работе обсуждена важность определения фенольных компонентов в растворимом кофе для оценки его качества. Особое внимание уделено компонентам «природного» и «технологического» происхождения, в качестве которых рассмотрены кофеилхинные кислоты (КХК) и катехол (КТ). Выбраны условия одновременного определения ХГК и КТ в образцах растворимого кофе методом капиллярного зонного электрофореза (КЗЭ). Разделение фенольных соединений проведено в среде боратного буфера (40 мМ, рН 9.5) при наложении напряжения +25 кВ на входной конец капилляра (60.5 (52) см ? 50 мкм). В рамках рассматриваемой методики предложено суммарное определение изомеров КХК методом КЗЭ. Правильность определения оценена способами «введено-найдено» (?отн = 7 %) и сравнением результатов анализа с результатами, полученными независимым методом, в качестве которого применяли метод ВЭЖХ-УФ (?отн = 4 %). Для обоснования «технологической» природы образования КТ в исследуемом продукте проанализированы образцы молотого зеленого и жареного кофе разной степени обжаривания, а также образцы растворимого кофе на содержание в них КХК и КТ электрофоретическим методом. Содержание КХК и КТ в образцах растворимого кофе варьируются в диапазонах 9-55 и 0.40-0.85 мг/г соответственно. Показано, что с увеличением степени обжаривания кофе наблюдается изменение содержания компонентов в образцах жареного молотого кофе: уменьшение КХК и увеличение КТ. Для образцов растворимого кофе установлена обратная корреляция ( r расч = 0.80; r табл= 0.40; n = 24) между содержаниями КХК и КТ, а также положительная корреляция ( r расч = 0.68; r табл = 0.51; n = 15) между содержанием КТ и индексом обжарки кофе. Это в совокупности подтверждает «технологическую» природу образования катехола в исследуемом продукте.

Tato diplomová práce se zabývá stanovením antioxidantů a alkaloidů v kávě. V teoretické části je popsáno složení kávy, technologický proces pražení kávy a možné způsoby stanovení antioxidantů a alkaloidů separačními technikami. Experimentální část je zaměřena na optimalizaci separace antioxidantů a alkaloidů v kávě pomocí kapalinové chromatografie s UV a hmotnostní detekcí a na optimalizaci přípravy vzorku k analýze. Vybrané podmínky byly použity pro stanovení antioxidantů a alkaloidů v zalévané kávě a kávě připravené v kávovaru. Dále byl zkoumán vliv pražení na obsah těchto látek v kávě., The aim of this diploma thesis is the determination of antioxidants and alkaloids in coffee. In theoretical part, the coffee composition and the technological process of coffee roasting as well as the possibility of determination of antioxidants and alkaloids by separation methods are described. The experimental part is focused on optimization of the separation of antioxidants and alkaloids in coffee by liquid chromatogaphy with UV and mass spectrometry detection and optimization of the sample preparation for the analysis. The selected conditions were used for the determination of antioxidants and alkaloids content in brewed coffee and in coffee prepared in coffeemaker. Furthermore, the influence of coffee roasting on alkaloids and antioxidants content in coffee was studied., Fakulta chemicko-technologická, Student, v průběhu obhajoby seznámil členy komise s cíly, úkoly a výsledky své práce.

Cílem práce bylo stanovení aldehydů nacházejících se v ovzduší v blízkosti firmy Saint-Gobain Construction Products CZ a.s., Častolovice a jeho okolí. Pro vzorkování ve venkovním ovzduší byla zvolena metoda pasivní dozimetrie se záchytem na pevný sorbent Florisil s naneseným derivatizačním činidlem 2,4-dinitrofenylhydrazinem (DNPH), na němž dochází k interakci aldehydů s DNPH za vzniku stabilních derivátů. Ty jsou následně eluovány acetonitrilem a analyzovány pomocí HPLC. Vzorky byly odebírány na třech místech ve třech etapách. Vzorkovače byly umístěny v ochranném boxu a připevněny na dobře větratelném místě., The aim of this work was the determination of aldehydes contained in air near the firm Gobain Construction Products CZ Častolovice and its neighbourhood. For outdoor air sampling the method of passive dosimetry with solid sorbent was selected. For this purpose Florisil with applied derivatisation agent 2,4-dinitrophenylhydrazin (DNPH) on which interaction of aldehydes with DNPH resulting in stable products creation is realised. These compounds were eluted using acetonitrile and analysed by HPLC. Sampling was realised from three places in three stages. Samplers were placed in the guard box and were fixed on well-ventilated place.

[ES] El principal problema en las estaciones de depuración de agua residual (EDAR) es la cantidad de fangos que se producen, ya que la gestión de los mismos es una operación costosa, y generan residuos con pocas posibilidades de reutilización. Una de las posibles soluciones a este problema, a nivel internacional, es la utilización de desacopladores metabólicos. Este método presenta la ventaja de ser un tratamiento in-situ que impide el crecimiento de los fangos generados en la EDAR, haciendo innecesarias (o menos frecuentes) las operaciones posteriores de tratamiento de los mismos. En este caso, se pretende despejar incógnitas que quedaron sin resolver en un trabajo anterior sobre la acción del desacoplador metabólico 3,3¿,4¿,5-tetracloro salicilanilida (TCS). Para ello se utilizarán, entre otras, técnicas analíticas avanzadas como cromatografía líquida de alta eficacia acoplado a un detector ultravioleta (HPLC-UV) o a un espectrómetro de masas (HPLC-MS) para analizar tanto el efluente del reactor SBR como el fango. Finalmente, se rediseñará una instalación del tratamiento de fangos utilizando este desacoplador y sin utilizarlo, con el objetivo de evaluar esta alternativa., [EN] The main problem in wastewater treatment plants (WWTP) is the high quantity of sludge that is produced, since the management of the sludge is an expensive operation, and to generate waste with little possibility of reuse. One of the possible solutions to solve this problem, at an international level, is the use of metabolic uncouplers. This method has the advantage of being an in-situ treatment that prevents the growth of the sludge generated in the WWTP, making unnecessary (or less frequent) operations of treatment of the sludge generated in WWTP. In this case, the aim of this work is to clarify unresolved unknowns from a previous work on the action of the metabolic uncoupler 3,3',4',5-tetrachloridesalicylanilide (TCS). For this purpose, advanced analytical techniques such as high-performance liquid chromatography coupled to an ultraviolet detector (HPLC-UV) or a mass spectrometer (HPLC-MS) will be used to analyze both the SBR reactor effluent and the sludge. Finally, a sludge treatment facility will be redesigned by using this product and without using it, in order to evaluate this alternative.

[ES] El principal problema en las estaciones de depuración de agua residual (EDAR) es la cantidad de fangos que se producen, ya que la gestión de los mismos es una operación costosa, y generan residuos con pocas posibilidades de reutilización. Una de las posibles soluciones a este problema, a nivel internacional, es la utilización de desacopladores metabólicos. Este método presenta la ventaja de ser un tratamiento in-situ que impide el crecimiento de los fangos generados en la EDAR, haciendo innecesarias (o menos frecuentes) las operaciones posteriores de tratamiento de los mismos. En este caso, se pretende despejar incógnitas que quedaron sin resolver en un trabajo anterior sobre la acción del desacoplador metabólico 3,3¿,4¿,5-tetracloro salicilanilida (TCS). Para ello se utilizarán, entre otras, técnicas analíticas avanzadas como cromatografía líquida de alta eficacia acoplado a un detector ultravioleta (HPLC-UV) o a un espectrómetro de masas (HPLC-MS) para analizar tanto el efluente del reactor SBR como el fango. Finalmente, se rediseñará una instalación del tratamiento de fangos utilizando este desacoplador y sin utilizarlo, con el objetivo de evaluar esta alternativa., [EN] The main problem in wastewater treatment plants (WWTP) is the high quantity of sludge that is produced, since the management of the sludge is an expensive operation, and to generate waste with little possibility of reuse. One of the possible solutions to solve this problem, at an international level, is the use of metabolic uncouplers. This method has the advantage of being an in-situ treatment that prevents the growth of the sludge generated in the WWTP, making unnecessary (or less frequent) operations of treatment of the sludge generated in WWTP. In this case, the aim of this work is to clarify unresolved unknowns from a previous work on the action of the metabolic uncoupler 3,3',4',5-tetrachloridesalicylanilide (TCS). For this purpose, advanced analytical techniques such as high-performance liquid chromatography coupled to an ultraviolet detector (HPLC-UV) or a mass spectrometer (HPLC-MS) will be used to analyze both the SBR reactor effluent and the sludge. Finally, a sludge treatment facility will be redesigned by using this product and without using it, in order to evaluate this alternative.

This project developed a novel hydrophilic interaction chromatography method for the detection and identification of nucleotides. The method was validated by testing biological specimens; adult and neonatal saliva, and red and white blood cell extracts. The project discovered an interesting difference between the adult and neonatal saliva specimens. The neonatal saliva contained 5 additional nucleotides and the nucleotides were present in greater concentrations, when compared to the concentrations in adult saliva. With further optimisation this method may be applied to testing in Pathology services and would facilitate the diagnosis of metabolic diseases that affect nucleotides.

[ES] El principal problema en las estaciones de depuración de agua residual (EDAR) es la cantidad de fangos que se producen, ya que la gestión de los mismos es una operación costosa, y generan residuos con pocas posibilidades de reutilización. Una de las posibles soluciones a este problema, a nivel internacional, es la utilización de desacopladores metabólicos. Este método presenta la ventaja de ser un tratamiento in-situ que impide el crecimiento de los fangos generados en la EDAR, haciendo innecesarias (o menos frecuentes) las operaciones posteriores de tratamiento de los mismos. En este caso, se pretende despejar incógnitas que quedaron sin resolver en un trabajo anterior sobre la acción del desacoplador metabólico 3,3¿,4¿,5-tetracloro salicilanilida (TCS). Para ello se utilizarán, entre otras, técnicas analíticas avanzadas como cromatografía líquida de alta eficacia acoplado a un detector ultravioleta (HPLC-UV) o a un espectrómetro de masas (HPLC-MS) para analizar tanto el efluente del reactor SBR como el fango. Finalmente, se rediseñará una instalación del tratamiento de fangos utilizando este desacoplador y sin utilizarlo, con el objetivo de evaluar esta alternativa., [EN] The main problem in wastewater treatment plants (WWTP) is the high quantity of sludge that is produced, since the management of the sludge is an expensive operation, and to generate waste with little possibility of reuse. One of the possible solutions to solve this problem, at an international level, is the use of metabolic uncouplers. This method has the advantage of being an in-situ treatment that prevents the growth of the sludge generated in the WWTP, making unnecessary (or less frequent) operations of treatment of the sludge generated in WWTP. In this case, the aim of this work is to clarify unresolved unknowns from a previous work on the action of the metabolic uncoupler 3,3',4',5-tetrachloridesalicylanilide (TCS). For this purpose, advanced analytical techniques such as high-performance liquid chromatography coupled to an ultraviolet detector (HPLC-UV) or a mass spectrometer (HPLC-MS) will be used to analyze both the SBR reactor effluent and the sludge. Finally, a sludge treatment facility will be redesigned by using this product and without using it, in order to evaluate this alternative.

The importance of dietary betaine is increasingly recognized. The aim of this study was to develop a simple high-performance liquid chromatography with standard ultraviolet spectrometric detection (HPLC-UV) method for betaine (N,N,N-trimethylglycine) determination in foods after derivatization. Two methods were used for betaine derivatization. Thereafter, derivatized betaine was quantified using HPLC-UV, and the results were compared with liquid chromatography mass spectrometry (LC-MS). The established derivatizing agent 2′-naphthacyl triflate and a novel derivatizing agent 2-bromo-2′-acetonaphthone produced the same cationic derivative when they react with betaine. The calibration curves were linear up to 1000 μmol/L (R 2 = 0.9974 for 2′-naphthacyl triflate and 0.9995 for 2-bromo-2′-acetonaphthone). The limit of detection was 1 μmol/L for both methods (2′-naphthacyl triflate and 2-bromo-2′-acetonaphthone), confirming sufficient sensitivity for betaine quantification in foods. The average recovery from different food matrices (wheat flour and spinach) (n = 12) was 99 ± 9 %, 95 ± 10 %, and 101 ± 8 % for LC-MS, 2′-naphthacyl triflate, and 2-bromo-2′-acetonaphthone, respectively. Inter- and intra-assay coefficients of variation (CVs) in the control samples (whole wheat flour) were below 10 %. Quantitative results for foods analyzed using 2′-naphthacyl triflate and 2-bromo-2′-acetonaphthone were comparable to LC-MS (R 2 = 0.992 and 0.990), respectively. The highest betaine content (~160 mg/100 g) was found in spinach followed by faba bean, wheat flour, and beetroot. These methods can be widely used for betaine quantification because of the simplicity of the derivatization procedures, and the commercial availability of the derivatizing reagent (2-bromo-2′-acetonaphthone) or through the relatively easy synthesis of 2-naphthacyl triflate.

[no abstract]

Apples are eaten as fresh fruits or as purees and dried fruit chips. The solvent extractionprocedure for accumulation of phenolic compounds from organically grown Idared appleswas optimized for HPLC-UV after extraction with diethyl ether. Furthermore theantioxidant capacity and the total phenolic content were determined. The influence ofaddition of ascorbic acid on the extraction was tested.Extraction recoveries were almost quantitative (85-115%) for phenolic compoundspresent in apples. (-)-epicatechin, quercetin, genistein, (-)-gallocatechin-3-gallate, pcoumaricacid and caffeic acid were identified in apple extracts in concentration (mg/kg)of 13.6, 1.5, 0.28, 0.23, 0.7 and 0.32, respectively.Antioxidant capacity in apples ranges from 145–322 μmol and for dry samples from 51-85 of μmol Trolox/100 g. The total phenol content of fresh apples is in a range from74.6–124 mg gallic acid/100 g. A decrease of 80% in phenolic compounds was registeredfor dried samples.

Honey is a valuable functional food rich in phenolic compounds with a broad spectrum of biological activities. Analysis of the phenolic compounds in honey is a very promising tool for the quality control, the authentication and characterization of botanical origin, and the nutraceutical research. This work describes a novel approach for the rapid analysis of five phenolic acids and 10 flavonoids in honey. Phenolic compounds were rapidly extracted and concentrated from diluted honey by dispersive liquid-liquid microextraction (DLLME) and then analyzed using high performance liquid chromatography with UV absorbance detection (HPLC-UV). Some important parameters, such as the nature and volume of extraction and dispersive solvents, pH and salt effect were carefully investigated and optimized to achieve the best extraction efficiency. Under the optimal conditions, an exhaustive extraction for twelve of the investigated analytes (recoveries >70%), with a precision (RSD<10%) highly acceptable for complex matrices, and detection and quantification limits at ppb levels (1.4-12 and 4.7-40ngg-1, respectively) were attained. The proposed method, compared with the most widely used method in the analysis of phenolic compounds in honey, provided similar or higher extraction efficiency, except in the case of the most hydrophilic phenolic acids. The capability of DLLME to the extraction of other honey phytochemicals, such as abscisic acid, was also demonstrated. The main advantages of developed method are the simplicity of operation, the rapidity to achieve a very high sample throughput and low cost. © 2014 Elsevier B.V

A rapid and selective HPLC-UV method was developed for the quantification of linezolid (LNZ) in human plasma and bronchoalveolar lavage (BAL) at the concentrations associated with therapy. Plasma samples were extracted by solid-phase extraction followed by evaporation to dryness and reconstitution in mobile phase solution. The chromatographic separation was carried out on a C18 column with an isocratic mobile phase consisting of dihydrogen phosphate buffer 50 mm (pH 3.5) and acetonitrile (60:40 v/v). The detection was performed using a photodiode array. Under these conditions, a single chromatographic run could be completed within 12 min. The method was validated by estimating the precision and the accuracy for inter- and intra-day analysis in the concentration range of 25-25600 ng/mL. The method was linear over the investigated range with all the correlation coefficients R > 0.999. The intra- and inter-day precision was within 8.90% and the accuracy ranged from -4.76 to +5.20%. This rapid and sensitive method was fully validated and could be applied to pharmacokinetic study for the determination of LNZ levels in human plasma and BAL samples.

Tato práce je zaměřena na izolace a stanovení vybraných antioxidantů v rostlinném materiálu. K tomuto účelu bylo vyuţito široké škály extrakčních metod, a to extrakční metody vyuţívající ultrazvukové lázně (USE) nebo ultrazvukové sondy (HOM), vysokotlakou extrakci rozpouštědlem (PFE), extrakci nadkritickou tekutinou (SFE) a klasickou extrakci v Soxhletově extraktoru. Orientačně byla testována také moţnost provedení výluhu antioxidantů do vody. Získané extrakty byly analyzovány metodou vysokoúčinné kapalinové chromatografie ve spojení se spektrofotometrickým detektorem v UV oblasti (HPLC-UV). Úvodní část je zaměřena na teoretické aspekty celé práce. Jsou zde popsány antioxidanty z hlediska jejich výskytu, vlastností, chemické struktury a jejich účinků v organismu. Dále jsou podrobně popsány extrakční metody jak pro izolaci antioxidantů, tak pro jejich analýzu, včetně kapitoly věnované různým technikám stanovení antioxidační kapacity. V experimentální části práce byly optimalizovány pracovní postupy pro všechny výše uvedené extrakční metody. Zvolené podmínky byly aplikovány na izolaci antioxidantů z 16 reálných vzorků rostlin. Dále byla vyvinuta vhodná HPLC-UV metoda, která byla pouţita při analýze získaných extraktů. U všech extraktů byla také stanovena jejich antioxidační kapacita. K tomuto účelu byla vyuţita metoda zaloţená na redukci 2,2-difenyl-1-pikrylhydrazyl radikálu (DPPH*), přičemž hodnota byla vyjádřena jako ekvivalent kyseliny galové (GAE)., This dissertation is focused on isolation and analysis of target antioxidant mixture in plant material. For this purpose several extraction techniques were used. These were ultrasonic bath extraction method (USE), ultrasonic probe extraction method (HOM), pressurised fluid extraction (PFE), supercritical fluid extraction (SFE) and method using the Soxhlet extractor. Water infusion was also tested. All obtained extracts were analysed by high performance liquid chromatography coupled with ultraviolet detector (HPLC-UV). The first part deals with theoretical aspects of the work. Antioxidants, their occurrence, characteristics, chemical structures and their effect on organisms are described. Also the fundamentals of the analytical methods for antioxidant extraction and their analysis are mentioned there. One chapter is also focused on different methods for antioxidant capacity evaluation. All extraction techniques were optimised in the experimental part of this work. Also the HPLC-UV method suitable for antioxidant analysis was optimised. Obtained conditions were applied for the 16 real plant samples analyses. The antioxidant capacity of all plant extracts was measured. For this purpose the method using the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH?) reduction was used, while the antioxidant capacity value was expressed as gallic acid equivalent (GAE)., Katedra analytické chemie, Komise souhlasí s tím, aby posudek oponentky doc. RNDr. Ireny Valterové, CSc. prezentoval předseda komise. Předseda komise doc. Ing. Jan Fischer, CSc. představil dizertanta a seznámil členy komise se základními životopisnými údaji.Vedoucí práce prof. Ing. Karel Ventura, CSc. prezentoval hodnocení dizertanta včetně jeho studijních a vědeckých výsledků. Prof. Ventura rovněž prezentoval stanovisko pracoviště k předkládané doktorské práci. Dizertant prezentoval výsledky doktorské práce a zodpověděl dotazy oponentů a členů komise. Proběhla diskuse týkající se posudků oponentů a především prezentovaných výsledků dizertační práce. Předseda konstatoval, že nebyly doručeny žádné písemné připomínky k dizertační práci. Komise i oponentka byli s prezentovanými výsledky i se závěry dizertanta včetně odpovědi na dotazy spokojeni. Diskuse proběhla i nad otázkou možností kvantifikace antioxidantů v reálných vzorcích i nad metodami určení detekčních limitů.

A fast and environmentally friendly procedure has been developed for Fenoxycarb determination in pesticide formulations by FTIR spectrometry. The method is based on an off-line extraction of the pesticide and stopped-flow measurement of the mid-IR spectra from 4000 to 850 cm-1 using a nominal resolution of 4 cm-1 and accumulating 25 scans. Fenoxycarb was determined using peak area measurements from 1509 to 1499 cm-1 corrected using a two points baseline defined between 1570 and 1403 cm-1. The proposed procedure has been compared with a reference chromatographic method. Results obtained by FTIR were statistically comparable to those found by HPLC. The developed method provided a LOD of 14 µg g-1, corresponding to 0.2 % (w/w) Fenoxycarb in the original sample and a sampling frequency of 60 h-1 with a waste generation of 3 mL CHCl3 for each sample. So, involving a reduction of organic solvent consume as compared with the HPLC method, which requires 55 mL CH3CN per sample, and a 6 times faster alternative than HPLC, which has a sampling frequency of 10 h-1.

Tato práce se zabývá aplikací moderní mikroextrakční techniky disperzní kapalinová mikroextrakce, která byla aplikována na izolaci antioxidantů z bylinných nápojů. Byla vypracována literární rešerše, která se zabývá přírodními a syntetickými antioxidanty a jejich vlastnostmi. Dále pak je zaměřena na možnosti izolace antioxidantů pomocí mikroextrakčních technik a následně pak jejich stanovení pomocí vysokoúčinné kapalinové chromatografie. V experimentální části byla provedena optimalizace disperzní kapalinové mikroextrakce (DLLME) v reálné bylinné matrici. Následně byl extrakt stanoven pomocí vysokoúčinné kapalinové chromatografie s UV-detekcí. Metoda po optimalizaci byla aplikována na reálné vzorky bylinných nálevů, u kterých byla rovněž stanovena antioxidační kapacita., This work deals with the application of the modern microextraction technique called dispersive liquid-liquid microextraction that was used for isolation of the target antioxidants from the herbal beverages. There was elaborated the literature search, that concerns natural and synthetic antioxidants with their properties. In addition it is aimed for the possibilities of the isolation of antioxidants using microextraction techniques and consequently their analysis with the high-performance liquid chromatography. In the experimental part of the work, there was accomplished optimization of the dispersive liquid?liquid microextraction (DLLME) in the real herbal matrix. Extracts were determined using high-performance liquid chromatography with UV-detection. This method after optimization was consequently applied to the real samples of the herbal infusions, where was also evaluated the antioxidant capacity., Katedra analytické chemie, Studentka přednesla obhajobu své diplomové práce a zodpověděla dotazy zkušební komise., Dokončená práce s úspěšnou obhajobou

Cílem této diplomové práce bylo stanovení vitaminů skupiny B v cereáliích pomocí chromatografické metody HPLC. Teoretická část práce se zabývá vlastnostmi vybraných vitaminů skupiny B, dále se zabývá popisem cereálií a metodou HPLC s UV detekcí. V praktické části je popsána metodika pro stanovení vitaminů skupiny B v cereáliích a stanovení vitaminu B2 v pšenici ozimé, dále je zde uvedeno stanovení hrubé bílkoviny v cereáliích pomocí Kjeldahlovy metody., The aim of this thesis was to determine the B group vitamins in cereals by HPLC chroma-tographic methods. The theoretical part deals with the properties of selected group B vitamins, also deals with the description of cereal and the HPLC method using UV detection. The experimental part describes the methodology for the determination of B group vitamins in cereals, isolation and determination of vitamin B2 in wheat, and there is also shown the determination of crude protein in cereals using the Kjeldahl method., Ústav biochemie a analýzy potravin, obhájeno

A reversed-phase high-performance liquid chromatography (HPLC) method was developed for the simultaneous determination in food of biogenic amines and their precursor amino acids after a precolumn derivatization with dansyl chloride. The chromatographic conditions, selected to be suitable for mass spectrometry detection, were optimized through experimental design and artificial neural networks. The HPLC-UV method was validated by comparing the separation results with those obtained through a HPLC method, working under the same chromatographic conditions but employing mass spectrometry detection. The HPLC-UV method was then applied to the analysis of different food samples, namely, cheese, clams, salami, and beer. For all of the matrices, recoveries (relative standard deviation always <5%) always >92% were obtained. The results are discussed as a function of the total biogenic amine content and of the concentration ratio between amines and precursor amino acids

Tato práce je zaměřena na aplikaci moderní extrakční techniky extrakce nadkritickou tekutinou (SFE) pro izolaci antioxidantů v bylinách a její porovnání s klasickou extrakční metodou v Soxhletově extraktoru. V teoretické části jsou popsány vybrané skupiny antioxidantů, jejich výskyt a vlastnosti. Dále pak metody izolace antioxidantů z rostlinné matrice a jejich stanovení vysokoúčinnou kapalinovou chromatografií. V experimentální části jsou popsány použité vzorky, přístroje a pracovní postupy. Práce byla zaměřena na optimalizaci extrakční techniky SFE pro izolaci vybraných antioxidantů z reálné bylinné matrice s následným stanovením vysokoúčinnou kapalinovou chromatografií s UV detekcí. Optimalizované metody byly aplikovány na různé vzorky bylin. Výsledky získané oběma metodami byly vzájemně porovnány., This work deals with the determination of selected antioxidants in herbs using modern extraction technique called supercritical fluid extraction (SFE) and its comparison with Soxhlet extraction. There are described selected groups of antioxidants, together with their incidence and characteristic properties in the theoretical part. Furthermore, the methods of antioxidants isolation from plants and their determination using high-performance liquid chromatography are presented as well. In the experimental part there are described analysed samples as well as devices and procedures used. This study is focused on the optimisation of both SFE and Soxhlet extraction metods for antioxidants isolation from herbs followed by the high-performance liquid chromatography coupled with UV detection. The optimised method was applied to different herbal samples analysis and the results were compared with values obtained by conventional extraction using Soxhlet extractor., Katedra analytické chemie, Dokončená práce s úspěšnou obhajobou

A fast method for the determination of brominated flame retardants (BFRs) in styrenic polymers using microwave-assisted extraction (MAE) and liquid chromatography with UV detection (HPLC-UV) was developed. Different extraction parameters (extraction temperature and time, type of solvent, particle size) were first optimised for standard high-impact polystyrene (HIPS) samples containing known amounts of tetrabromobisphenol A (TBBPA) and decabromodiphenyl ether (Deca-BDE). Complete extraction of TBBPA was achieved using a combination of polar/non-polar solvent system (isopropanol/n-hexane) and high extraction temperatures (130 degrees C). Lower extraction yields were, however, obtained for Deca-BDE, due to its high molecular weight and its non-polar nature. The developed method was successfully applied to the screening of BFRs in standard plastic samples from waste electrical and electronic equipment (WEEE): TBBPA could be fully recovered, and Deca-BDE could be identified, together with minor order polybrominated diphenyl ether (PBDE) congeners., QC 20100525

Tato diplomová práce se zabývá různými vlivy přípravy černého a zeleného čaje na obsah fenolických látek, které se stanovují metodou vysokoúčinné kapalinové chromatografie. V teoretické části je bližší seznámení s čajem a jeho výrobou. Podrobně jsou popsány složky čaje a jejich prospěšný účinek na lidské zdraví. V experimentální části je analyzováno 18 fenolických látek vyskytujících se v čaji vysokoúčinnou kapalinovou chromatografií s UV detekcí (HPLC-UV). V závěrečné části práce byly srovnávány obsahy fenolických látek v čajových nálevech při různé době luhování čajových lístků., This diploma thesis deals with different influence of black and green tea preparation on phenolic substances content. To set their content high-performance liquid chromatography was used. In the theoretical part there is more detailed description of tea and its processing and manufacturing. Precisely described are all tea compounds and its positive impact on human health. n the experimental part 18 phenolic substances found in tea were analysed by using high-performance liquid chromatography with UV detection (HPLC-UV). Phenolic compounds contents in tea solutions were compared in the last part of the thesis. Contents were compared according to different infuse times., Katedra analytické chemie, Dokončená práce s úspěšnou obhajobou

Tato práce se zabývá stanovením vybraných antioxidantů především vitaminu C v nealkoholických nápojích. Je zaměřena především na využití moderních mikroextrakčních technik, zejména na mikroextrakci se sorbentem v mikrostříkačce (MEPS) a její optimalizace s následným stanovením pomocí HPLC s UV detekcí. Jsou zde blíže popsány známé antioxidanty a jejich vlastnosti, charakteristika a technologie čaje a principy mikroextrakčních technik, jakými jsou mikroextrakce tuhou fází (SPME), mikroextrakce na magnetickém míchadle (SBSE) a mikroextrakce se sorbentem v mikrostříkačce (MEPS)., This thesis deals with the determination of selected antioxidants in alcohol-free beverages. It is focused especially to the application of modern microextraction techniques. Namely, microextraction by packed sorbent (MEPS) and especially optimisation of MEPS followed by high-performance liquid chromatography with UV detector is described. The description of antioxidants and their properties, characterisrics of tea and its technology and the basic principles of used microextraction techniques. The techniques such as solid phase microextraction (SPME), stir bar sorptive microextraction and microextraction by packed sorbent (MEPS) are described in more details., Katedra analytické chemie, Dokončená práce s úspěšnou obhajobou

Tato práce se zabývá stanovením vybraných antioxidantů v rostlinném materiálu. Je zaměřena především na využití moderních extrakčních technik, zejména na vysokotlakou extrakci rozpouštědlem (PFE), extrakci v ultrazvukové lázni (USE) a extrakci pomocí ultrazvukové sondy (HOM). V teoretické části je bližší seznámení s antioxidanty, jejich vlastnostmi a výskytem. Jsou zde podrobně popsány principy použitých extrakčních technik a zvolené analytické koncovky, tedy vysokoúčinné kapalinové chromatografie. V experimentální části jsou uvedeny analyzované vzorky bylin a charakteristika standardů sledovaných antioxidantů. Dále zde lze nalézt použité přístroje a pracovní postupy. Část výsledky a diskuze se především zaměřuje na úpravu vzorků, tedy na optimalizaci extrakční techniky (PFE). Dále je zde popsána následná analýza extraktů pomocí kapalinové chromatografie s využitím UV detekce (HPLC-UV). V závěru této části jsou na základě analýzy 10 reálných vzorků bylin porovnány použité extrakční metody., This thesis deals with the determination of selected antioxidants in plant material. It is focused especially to the application of modern extraction techniques. Those are pressurized fluid extraction (PFE), ultrasonic bath extraction (USE) and ultrasonic extraction with homogenizer (HOM). Further, description of antioxidants, its characteristics and appearance are included in the theoretical part. Also the basic principles of used extraction techniques together with high-performance liquid chromatography are described in details. In the experimental part there are presented all analysed plants together with standards characterization. Instrument descriptions together with used procedures are included as well. Sample preparation procedure and especially optimisation of PFE conditions are mentioned in the results and discussion part. Analysis of individual extract by high-performance liquid chromatography with UV detector is also described in this part. Finally, the comparison of various extraction methods based on the contents of target compounds in 10 real plant samples was performed., Katedra analytické chemie, Dokončená práce s úspěšnou obhajobou

Ce travail de thèse rentre dans le cadre d’un projet de recherche appliquée mené à l’Institut National de Criminalistique et de Criminologie s’intitulant « développement d’un système intégral de détection et d’identification de résidus de tir » visant à doter le laboratoire de balistique chimique d’un outil performant pour la recherche et la caractérisation des résidus de tir aussi bien inorganiques qu’organiques. Comme nous l’expliquons dans le chapitre 1, l’analyse des résidus de tir est aujourd’hui essentiellement basée sur la mise en évidence par microscopie électronique à balayage des particules métalliques provenant de l’amorce. Cette pratique a des limites. Introductif, ce chapitre met en lumière la relation entre criminologie et criminalistique, donne un aperçu de la classification des armes et décrit les relations entre les armes de poing, les munitions, les résidus de tir et la criminalistique. La motivation de l’analyse de résidus organiques et plus particulièrement des stabilisants pour poudres propulsives y est aussi expliquée. Le but principal de ce travail étant le développement d’une méthode d’analyse des stabilisants par spectrométrie de masse en tandem couplée à la chromatographie liquide à haute performance (LC-MS/MS), ce premier chapitre aborde de façon détaillée le principe de fonctionnement d’un spectromètre de masse quadripolaire, qu’il soit avec simple quadripôle ou en tandem, et traite avec une attention particulière les aspects relatifs à la production d’ions, l’acquisition des données et la détection des ions.Le chapitre 2 est consacré aux résultats et discussions. Comme point de départ de tous les travaux ultérieurs, l’optimisation du fonctionnement du spectromètre et plus particulièrement la détermination des « ions précurseurs » et des « ions produits » y est traitée en détails. De plus, l’étude de la fragmentation des ions précurseurs y occupe une place prépondérante et conditionne l’établissement d’une méthode de détection et d’acq, Doctorat en Sciences, info:eu-repo/semantics/nonPublished

Ce travail de thèse rentre dans le cadre d’un projet de recherche appliquée mené à l’Institut National de Criminalistique et de Criminologie s’intitulant « développement d’un système intégral de détection et d’identification de résidus de tir » visant à doter le laboratoire de balistique chimique d’un outil performant pour la recherche et la caractérisation des résidus de tir aussi bien inorganiques qu’organiques. Comme nous l’expliquons dans le chapitre 1, l’analyse des résidus de tir est aujourd’hui essentiellement basée sur la mise en évidence par microscopie électronique à balayage des particules métalliques provenant de l’amorce. Cette pratique a des limites. Introductif, ce chapitre met en lumière la relation entre criminologie et criminalistique, donne un aperçu de la classification des armes et décrit les relations entre les armes de poing, les munitions, les résidus de tir et la criminalistique. La motivation de l’analyse de résidus organiques et plus particulièrement des stabilisants pour poudres propulsives y est aussi expliquée. Le but principal de ce travail étant le développement d’une méthode d’analyse des stabilisants par spectrométrie de masse en tandem couplée à la chromatographie liquide à haute performance (LC-MS/MS), ce premier chapitre aborde de façon détaillée le principe de fonctionnement d’un spectromètre de masse quadripolaire, qu’il soit avec simple quadripôle ou en tandem, et traite avec une attention particulière les aspects relatifs à la production d’ions, l’acquisition des données et la détection des ions.Le chapitre 2 est consacré aux résultats et discussions. Comme point de départ de tous les travaux ultérieurs, l’optimisation du fonctionnement du spectromètre et plus particulièrement la détermination des « ions précurseurs » et des « ions produits » y est traitée en détails. De plus, l’étude de la fragmentation des ions précurseurs y occupe une place prépondérante et conditionne l’établissement d’une méthode de détection et d’acq, Doctorat en Sciences, info:eu-repo/semantics/nonPublished

PURPOSE: The radiolytic products of eight beta-blockers were studied in order to understand the mechanisms of irradiation of drugs in the solid state. METHODS: The drugs were analyzed by high-performance liquid chromatography coupled to a diode array detector in order to observe the degradation of the main compound after irradiation and in order to study the nonvolatile final products on more concentrated solutions of irradiated drugs. RESULTS: The first test assessed that the main compound was not significantly degraded after gamma irradiation for any of the eight beta-blockers. A more complete study, which consisted on separating the nonvolatile products and on quantifying them, indicated first that the radiolytic products could reach the number of 14 and moreover that some could exceed the 0.1% threshold at 30 kGy. Eventually, radiolytic yields were compared with radical yields previously determined. CONCLUSIONS: The sensitivity of the first test can be discussed. It seems that, to study the feasibility of the radiosterilization, a complete study of the products of degradation is needed. Moreover, no correlation between radical and final products could be established, which denies that the former would be the precursors of the latter.

submitted by Klemens Losso, Abweichender Titel laut Übersetzung des Verfassers, Zusammenfassung in deutscher Sprache, Diplomarbeit University of Innsbruck 2018

submitted by Klemens Losso, Abweichender Titel laut Übersetzung des Verfassers, Zusammenfassung in deutscher Sprache, Diplomarbeit University of Innsbruck 2018

There is extensive literature on in vivo studies with cordycepin but these studies were generally conducted without validation of the various formulations, especially in terms of the solubility of cordycepin in the dosing vehicles used. Cordycepin is a promising drug candidate in multiple therapeutic areas and there is a growing interest in studies aimed at assessing the pharmacological activity of this compound in relevant animal disease models. It is likely that many reported in vivo studies used formulations in which cordycepin was incompletely soluble. This can potentially confound the interpretation of pharmacokinetics and efficacy results. Furthermore, the presence of particles in intravenously administered suspension can cause adverse effects and should be avoided. Here we present the results from our development of simple and readily applicable formulations of cordycepin based on quantitative solubility assessment. Homogeneous solutions of cordycepin were prepared in phosphate-buffered saline (PBS) at different pH levels, suitable as formulations for both intravenously and oral administration. For the purpose of high-dose oral administration we also developed propylene glycol (PPG)-based vehicles in which cordycepin is completely soluble. The stability of the newly developed formulations was also assessed, as well the feasibility of their sterilisation by filtration. Additionally, an HPLC-UV method for the determination of cordycepin in the formulations, which may also be useful for other purposes, was developed and validated. Our study could provide useful information for improvement of future preclinical and clinical studies involving cordycepin.

There is extensive literature on in vivo studies with cordycepin but these studies were generally conducted without validation of the various formulations, especially in terms of the solubility of cordycepin in the dosing vehicles used. Cordycepin is a promising drug candidate in multiple therapeutic areas and there is a growing interest in studies aimed at assessing the pharmacological activity of this compound in relevant animal disease models. It is likely that many reported in vivo studies used formulations in which cordycepin was incompletely soluble. This can potentially confound the interpretation of pharmacokinetics and efficacy results. Furthermore, the presence of particles in intravenously administered suspension can cause adverse effects and should be avoided. Here we present the results from our development of simple and readily applicable formulations of cordycepin based on quantitative solubility assessment. Homogeneous solutions of cordycepin were prepared in phosphate-buffered saline (PBS) at different pH levels, suitable as formulations for both intravenously and oral administration. For the purpose of high-dose oral administration we also developed propylene glycol (PPG)-based vehicles in which cordycepin is completely soluble. The stability of the newly developed formulations was also assessed, as well the feasibility of their sterilisation by filtration. Additionally, an HPLC-UV method for the determination of cordycepin in the formulations, which may also be useful for other purposes, was developed and validated. Our study could provide useful information for improvement of future preclinical and clinical studies involving cordycepin.

Analysis of Artemisia annua extracts by liquid chromatographic methods has traditionally been complicated by the presence of significant quantities of impurities. It has been observed that these impurities often remain as a solid residue after sample reconstitution, but the possibility of artemisinin remaining entrained within this waxy layer has not been detailed in the literature. This investigation found that A. annua extract impurities have a critical impact on the quantification of artemisinin by liquid chromatographic methods. Extended sample reconstitution times of up to 24 hours are required in order for the mobile phase (acetonitrile) to penetrate the residue and solubilise the artemisinin contained within. Extracts produced using ethyl acetate, hexane-ethyl acetate (95:5, v/v), hexane and ethanol were examined in the study. Extended residue reconstitution times resulted in a significant increase in the number and concentration of impurities in the mobile phase, requiring the development of a new HPLC-UV analytical method to exact adequate separation of artemisinin for quantification. The solvent selectivity and capacity for each of the solvent extraction approaches was then determined using the new reconstitution and HPLC-UV methods.

Analysis of Artemisia annua extracts by liquid chromatographic methods has traditionally been complicated by the presence of significant quantities of impurities. It has been observed that these impurities often remain as a solid residue after sample reconstitution, but the possibility of artemisinin remaining entrained within this waxy layer has not been detailed in the literature. This investigation found that A. annua extract impurities have a critical impact on the quantification of artemisinin by liquid chromatographic methods. Extended sample reconstitution times of up to 24 hours are required in order for the mobile phase (acetonitrile) to penetrate the residue and solubilise the artemisinin contained within. Extracts produced using ethyl acetate, hexane-ethyl acetate (95:5, v/v), hexane and ethanol were examined in the study. Extended residue reconstitution times resulted in a significant increase in the number and concentration of impurities in the mobile phase, requiring the development of a new HPLC-UV analytical method to exact adequate separation of artemisinin for quantification. The solvent selectivity and capacity for each of the solvent extraction approaches was then determined using the new reconstitution and HPLC-UV methods.