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A simple high-performance thin layer Chromatographie (HPTLC) method has been developed for the determination of atrazine and simazine herbicides in drinking and surface waters. The method involves solid-phase extraction on C18 Bakerbond cartridges followed by development of the concentrated extracts on HPTLC silica plates with a nitromethane-tetrachloromethane (1:1, v/v) mobile phase and quantitation by UV scanning densitometry. Using the proposed mobile phase composition, pronounced background suppression on the chromatograms of the real water samples was accomplished. The detection limits of the method were 30 and 60 ng l for atrazine and simazine, respectively, at the 80–400 ng l fortification level in the surface waters. The method was successfully applied to the analyses of tap and surface waters with overall recoveries between 58 and 93% and a relative standard deviation below 12%. The results show, that the HPTLC method is sufficiently selective and sensitive to be employed in screening of contaminated waters containing the triazines below the maximum residues limits of the European Community.

o-Phthaldialdehyde in combination with 1-thio-β- d -galactose is a powerful chiral reagent for the precolumn derivatization of primary amino acids. The diastereomers formed can be efficiently resolved on conventional reversed-phase columns. Comparison of 1-thio-β- d -galactose with 1-thio-β- d -glucose revealed that even the change of the configuration of the remote OH group on the sugar moiety influences the resolution of d , l -amino acid derivatives.

Tall oil soap as a waste product of the sulphate cellulose production process was treated by single-stage liquid-liquid extraction. The aim of this study was to compare yields of health beneficial matters contained in tall oil soap when several extraction solvents, recommended in literature, were used. Hexane, 1-methyl-4-(1-methylethenyl)-cyclohexene, 2-methylpropan-1-ol, hexan-1-ol, 4-methylpentan-2-one, 2-methoxy-2-methylpropane, and butyl ethanoate were tested. For hydrocarbons it was necessary to add a de-emulsifier into the system, which limits the formation of foams and stable emulsions. The highest yields of total phytosterols (78 %) and especially of β-sitosterol (100 %) were reached when butyl ethanoate was used. However, it was necessary to adjust pH of the treated raw material to approximately 7. The highest yields for feed where pH was not adjusted were obtained with 2-methylpropan-1-ol: 67 % of total sterols and 89 % of β-sitosterol. Disadvantages of most of the tested solvents included the formation of the undesirable solid interphase which could not be removed, partial solubility of the solvents in the water phase, their high boiling point and/or instability. These disadvantages prevent the use of these solvents in industrial applications; they also complicate the treatment of tall oil soap by liquid-liquid extraction or the regeneration of the used organic solvent.

Raman spectroscopy can elucidate fundamental questions about intercellular variability and what governs it. Moreover, knowing the metabolic response on single cell level this can significantly contribute to the study and use of microalgae in systems biology and biofuel technology. Raman spectroscopy is capable to measure nutrient dynamics and metabolism in vivo, in real-time, label free making it possible to monitor/evaluate population variability. Also, degree of unsaturation of the algae oil (iodine value) can be measured using Raman spectra obtained from single microalgae. The iodine value is the determination of the amount of unsaturation contained in fatty acids (in the form of double bonds). Here we demonstrate the capacity of the spatially resolved Raman microspectroscopy to determine the effective iodine value in lipid storage bodies of individual living algal cells. We employed the characteristic peaks in the Raman scattering spectra at 1,656 cm -1 (cis C=C stretching mode) and 1,445 cm -1 (CH 2 scissoring mode) as the markers defining the ratio of unsaturated-to-saturated carbon-carbon bonds of the fatty acids in the algal lipids.

The aim of this study was to determine the efficacy of selected basidiomycetes in the removing of polycyclic aromatic hydrocarbons (PAH) from the creosote-contaminated soil. Fungi Pleurotus ostreatus and Irpex lacteus were supplemented with creosote-contaminated (50-200 mg kg(-1) PAH) soil originating from a wood-preserving plant and incubated at 15 °C for 120 d. Either fungus degraded PAH with 4-6 aromatic rings more efficiently than the microbial community present initially in the soil. PAH removal was higher in P. ostreatus treatments (55-67%) than in I. lacteus treatments (27-36%) in general. P. ostreatus (respectively, I. lacteus) removed 86-96% (47-59%) of 2-rings PAH, 63-72% (33-45%) of 3-rings PAH, 32-49% (9-14%) of 4-rings PAH and 31-38% (11-13%) of 5-6-rings PAH. MIS (Microbial Identification System) Sherlock analysis of the bacterial community determined the presence of dominant Gram-negative bacteria (G-) Pseudomonas in the inoculated soil before the application of fungi. Complex soil microbial community was characterized by phospholipid fatty acids analysis followed by GC-MS/MS. Either fungus induced the decrease of bacterial biomass (G- bacteria in particular), but the soil microbial community was influenced by P. ostreatus in a different way than by I. lacteus. The bacterial community was stressed more by the presence of I. lacteus than P. ostreatus (as proved by the ratio of the fungal/bacterial markers and by the ratio of trans/cis mono-unsaturated fatty acids). Moreover, P. ostreatus stimulated the growth of Gram-positive bacteria (G+), especially actinobacteria and these results indicate the potential of the positive synergistic interaction of this fungus and actinobacteria in creosote biodegradation.

Microorganism Pseudomonas species P2 metabolizes polychlorinated biphenyls (PCBs) and biphenyl, producing the whole spectrum of intermediates, among them coloured intermediates, which are suitable for the monitoring of PCBs degradation by optical sensors. Knowledge of chemical structures and conditions of development of colour metabolites is necessary for application of optical analytical methods. The main goal of this work was the isolation and identification of intermediates from the biodegradation of the mixture of low chlorinated biphenyls (Delor-103), which is based on the solid phase extraction (SPE) of the whole mixture using LiChrolut EN cartridges, then silylation of the extract as one way to the identification of one part of intermediates by GC–MS, and acetylation of the extract as a way for the further concentration and analysis of more polar chlorobiphenylols and chlorobiphenyldiols. The combination of SPE and following acetylation allows to obtain chlorobiphenylols and chlorobiphenyldiols as an almost pure fraction. The acetylation method could be also used instead SPE procedure with the same final concentration effect. Using the simulation mass spectrometry program, two new compounds, dihydrodihydroxytrichloro- and tetrahydrodihydroxytrichlorobiphenyl, as silylderivatives, were identified.

Application of gas chromatography-mass spectrometry (GC-MS) can significantly improve trace analyses of compounds in complex matrices from natural environments compared to gas chromatography only. A GC-MS/MS technique for determination of poly-beta-hydroxybutyrate (PHB), a bacterial storage compound, has been developed and used for analysis of two soils stored for up to 319 d, fresh samples of sewage sludge, as well as a pure culture of Bacillus megaterium. Specific derivatization of beta-hydroxybutyrate (3-OH C4:0) PHB monomer units by N-tert-butyl-dimethylsilyl-N-methyltrifluoracetamide (MTBSTFA) improved chromatographic and mass spectrometric properties of the analyte. The diagnostic fragmentation scheme of the derivates tert-butyldimethylsilyl ester and ether of beta-hydroxybutyric acid (MTBSTFA-HB) essential for the PHB identification was shown. The ion trap MS was used, therefore the scan gave the best sensitivity and with MS/MS the noise decreased, so the S/N was better and also with second fragmentation the amount of ions increased compared to SIM. The detection limit for MTBSTFA-HB by GC-MS/MS was about 10(-13) g microL(-1) of injected volume, while by GC (FID) and GC-MS (scan) it was around 10(-10) g microL(-1) of injected volume. Sensitivity of GC-MS/MS measurements of PHB in arable soil and activated sludge samples was down to 10 pg of PHB g(-1) dry matter. Comparison of MTBSTFA-HB detection in natural soil sample by GC (FID), GC-MS (scan) and by GC-MS/MS demonstrated potentials and limitations of the individual measurement techniques.

Polycyclic aromatic hydrocarbons (PAHs) were analysed in mosses (Hypnum cupressiforme) and pine needles (Pinus sylvestris) collected in the Czech Republic between 1988-94 at a regional background site in Kosetice, south Bohemia (1988-94) and two industrial sources. One industrial site (sampled 1989-91) in middle Moravia, was near a factory producing PAHs, carbon black and phthalates, the other (sampled 1991-93) near a coal and gas fuel production plant in western Bohemia. Selected chlorinated pesticides and polychlorinated biphenyl congeners were also analysed in samples at the regional background site. This study clearly shows that vegetation sampling can be used to show spatial differences in the atmospheric burden of a range of persistent organic pollutants with differences in the mixtures of compounds reflecting differences in their regional or local use/atmospheric emission.

Higher aliphatic amines and cyclohexylamine find use on a large scale as inhibitors of corrosion in power stations and in installations for drawing and storing natural gas in underground containers. The determination of active constituents of the inhibitors at the individual technological steps, very important for assessing the efficacy of the anticorosive protection, is complicated by other compounds accompanying the trace amounts of the amines being monitored. This circumstance makes it necessary to use selective methods based on the derivatization of the primary amino group and formation of intensively UV-VIS absorbing or fluorescent derivatives.

Rearrangement of 2-oximinoadamantane in hydrobromic acid and its dependence on acid concentration, temperature and reaction time was studied. The reaction affords 4-bromoadamantan-2-one, together with 4-azatricyclo[4,3,1,13,8]undecan-5-one and 4-hydroxyadamantan-2-one. This reaction can be used as a preparative method for synthesis of 4-bromoadamantan-2-one.

A one-step synthesis of mixture of stereoisomers of 4-bromoadamantan-2-one based on the reaction of adamantan-2-one with hydroxylamine hydrochloride in hydrobromic acid is described. The pure stereoisomers were isolated by elution chromatography on silica gel, and their NMR spectra with the Eu(FOD)3 shift reagent, mass spectra, IR spectra, and dipole moments were measured.

The reaction in mixtures of adamantanone with hydroxylamine hydrochloride was studied in hydrochloric, hydrobromic, and hydroiodic acid solutions. In hydrochloric and hydroiodic acids, mixtures of isomers of 4-chloroadamantan-2-one and 4-iodoadamantan-2-one, respectively, are formed, whereas in hydrobromic acid in the presence of excess hydroxylamine hydrochloride, three stereoisomers of 4,8-dibromoadamantan-2-one appear. All the stereoisomeric haloketones were isolated by elution adsorption chromatography on silica gel or by crystalization. For the pure substances, their infrared, mass, and NMR spectra were measured.

13C NMR spectra of 3,5-dehydrodiamantane were compared with those of diamantanoid compounds with and without a cyclopropane ring. The effect of the cyclopropane ring in 3,5-dehydrodiamantane is similar to that for the carbon atoms of 2,4-dehydroadamantane and 2,4-methano-2,4-dehydroadamantane, but not for 1,3-dehydroadamantane. One-bond coupling constants [1J(CH)] are discussed in terms of ring size and compared with bond angles. The observed difference between 1J(CH) of CH and CH2 groups of diamantanoid skeletons is connected with a change of the number of equatorial or axial positions of CH bonds in the cyclohexane ring.

A sensitive system for D,L-amino acid analysis has been developed, using fluorescence derivatization with o-phthaldialdehyde in the presence of sodium salt of 1-thio-beta-D-glucose. The reagents rapidly form fluorescent diastereoisomeric derivatives with primary amino acids. These derivatives are efficiently separated on a conventional reversed-phase column with an analysis time of 60 min. Simultaneous determination of enantiomers of various amino acids was achieved by a simple binary gradient elution with methanol in 0.05 M aqueous sodium acetate.

The aim of this project was to study changes in the content of trans -resveratrol in berries and leaves of grapevine ( Vitis sp.) infested by fungal diseases, especially by Botryotinia fuckeliana Whetzel, called as grey mildew, Plasmopara viticola (Berk. & M.A. Curtis) Berl & De Toni, called downy mildew and Uncinula necator (Schw.) Burr, called powdery mildew. In our experiments two white and two blue varieties were used. Contents of trans -resveratrol were determined in healthy and infested leaves and in healthy berries. Infested leaves of white varieties contained more trans -resveratrol than those of blue varieties. The content of trans -resveratrol in berries was lower than that in leaves.

The effect of soil contamination by polycyclic aromatic hydrocarbons (PAH) and heavy metals on earthworms and enchytraeids was studied in urban parks, in Brno, Czech Republic. In spring and autumn 2007, annelids were collected and soil samples taken in lawns along transects, at three different distances (1, 5 and 30 m) from streets with heavy traffic. In both seasons, two parks with two transects each were sampled. Earthworms were collected using the electrical octet method. Enchytraeids were extracted by the wet funnel method from soil cores. All collected annelids were counted and identified. Basic chemical parameters and concentrations of 16 PAH, Cd, Cu, Pb, and Zn were analysed from soil from each sampling point. PAH concentrations were rather low, decreasing with the distance from the street in spring but not in autumn. Heavy metal concentrations did not decrease significantly with increasing distance. Annelid densities did not significantly differ between distances, although there was a trend of increase in the number of earthworms with increasing distance. There were no significant correlations between soil content of PAH or heavy metals and earthworm or enchytraeid densities. Earthworm density and biomass were negatively correlated with soil pH; and enchytraeid density was positively correlated with soil phosphorus. O efeito da contaminação do solo por hidrocarbonetos aromáticos policíclicos (PAH) e metais pesados em minhocas e enquitreídeos foi estudado em parques urbanos, em Brno, República Tcheca. Na primavera e outono de 2007, os anelídeos foram coletados, e amostras de solo foram retiradas de gramados ao longo de transectos, em três diferentes distâncias (1, 5 e 30 m) de ruas com muito tráfego. Nas duas estações, foram amostrados dois parques com dois transectos cada um. As minhocas com uso do método do octeto elétrico, e os enquitreídeos foram extraídos das amostras de solo pelo método do funil úmido. Todos os anelídeos coletados foram contados e identificados. Parâmetros químicos básicos e concentrações de 16 PAHs, Cd, Cu, Pb e Zn, de cada ponto de amostragem, foram analisados. As concentrações de PAH foram relativamente baixas, e decresceram na primavera, mas não no outono, com a distância da rua. As concentrações de metais pesados não diminuíram significativamente com o aumento da distância. As densidades de anelídeos não diferiram significativamente entre as distâncias, mas houve tendência de aumento no número de minhocas, com o aumento da distância. Não houve correlação significativa entre o conteúdo de PAH ou metais pesados do solo com as densidades de minhocas e enquitreídeos. A densidade e a biomassa das minhocas foram negativamente correlacionadas ao pH do solo; e a densidade de enquitreídeos foi positivamente correlacionada ao conteúdo de fósforo no solo.

The effects of the pressing technology and clarification of white grape musts on concentrations of phenolic compounds and their antioxidative capacity were investigated. Four different varieties were processed by hydraulic or pneumatic pressing technologies. In the individual stages of pressing and after the application of different doses of the clarification agent, must samples were analysed for the content of polyphenols and the antioxidative capacity. The highest concentrations of caftaric acid were estimated in the musts made by hydraulic pressing from grapes of Welschriesling variety. On the other hand, musts made from grapes of Gruner Veltliner showed the highest contents of trans-piceid in both variants of pressing. The values of antioxidative capacity of the must samples analysed were not significantly different. The influence of clarification on the changes of phenolic substances in young red wines of Saint Laurent variety was also studied. Six various clarifiers were tested as applied in two different doses. Polyvinylpolypyrrolidone caused the highest losses of trans-resveratrol in the course of red wine clarification. The concentrations of catechin, epicatechin, and total anthocyanins as well as the colour parameters of red wines were influenced at most by the application of egg white.

The occurrence and content of some polyphenols and the antioxidant activity of compounds present in grape berries, stems and leaves of Vitis vinifera L. were evaluated. Three white and three blue varieties of grapevine were investigated. The contents were determined of trans-resveratrol, trans-piceid, caftaric acid, tryptophan, catechin, epicatechin, total polyphenols, and flavanols, both in healthy material and in the samples of the plant material infested with microorganisms (Botryotinia fuckeliana Whetzel anamorph Botrytis cinerea Pers.; Uncinula necator (Schw.) Burr; Plasmopara viticola (Berk. & M.A. Curtis) Berl & De Toni). The antioxidant activity of the extracts obtained was determined by different methods: FRAP (Ferric Reducing Antioxidant Power), DPPH (2,2-diphenyl-1-picrylhydrazyl radical) and TAC-PCL (Total Antioxidant Capacity of Photochemiluminescence). The content of trans-resveratrol varied between 0.3-2.3 mg/kg and 0.7-12.1 mg/kg in non-infested and infested grape berries, respectively. The content of trans-piceid between 0.6-2.9 mg/kg and 1.5-6.3 mg/kg in non-infested and infested grape berries, respectively. The content of trans-resveratrol varied between 2.5-10.3 mg/kg and 3.7-20.9 mg/kg in healthy and in infected leaves, respectively. The content trans-piceid varied between 11.3-58.4 mg/kg and 18.5-60.9 mg/kg in the healthy and in the infected leaves, respectively. The highest content of trans-resveratrol was found in stems (16.3-276.3 mg/kg). In young lateral shoots, the highest levels of trans-piceid (12.6-99.7 mg/kg) and caftaric acid (474-2257 mg/kg) were determined. The infested grape berries showed a higher antioxidant activity, which was most closely correlated with the content of total polyphenols (correlation coefficient = 0.8336-0.9952).

Antioxidant activity and free radicals were studied in various parts of Vitis vinifera plant in vivo and in wines using EPR spectroscopy. Antioxidative properties of polyphenolic substances play an important role for the evaluation of quality of natural products. Determination of antioxidant activity of experimental samples by EPR method was based on measuring the changes of EPR spectrum of stable nitroxide radicals as a result of their interaction with antioxidants. In the leaves of Vitis vinifera vine varieties for the production of red wines there was observed a higher decrease in free Tempol radicals as compared to the leaves of varieties used for the production of white wines. For all monitored wines there was established a clear decrease in free Tempol radicals to the average value of 75.5 ± 15.6% as compared to the original EPR spectrum. A higher antioxidant activity was observed in yeast sediments from the production of red wines than in those from white ones.

Landfeld A., Třiska J., Balik J., Strohalm J., Novotna P., Vrchotova N., Totusek J., Lefnerova D., Hic P., Tomankova E., Halama R., Houska M. (2015): Influence of UV and ozonised water treatment on trans-resveratrol content in berry skins and juices of Franc and Green Veltliner grapes. Czech J. Food Sci., 33: 267–276. Grapes from two varieties – Franc (red) and Green Veltliner (white) were processed using UV radiation at selected powers and times. Irradiated grapes were stored for 24, 48, and 72 h at room temperature. A second set of grapes was dipped into ozonised water. We tested the influence of ozone concentration, dipping time, and storage time. All experiments were performed using grapes harvested in 2009, 2010, and 2011. The two treatments were compared relative to trans-resveratrol content in grape skins and juices (prepared from treated grapes).