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51.
52.
Wojciech Mrozik Christian Jungnickel Tomasz Ciborowski William Robert Pitner Jolanta Kumirska Zbigniew Kaczyński Piotr Stepnowski 《Journal of Soils and Sediments》2009,9(3):237-245
Background, aim, and scope Ionic liquids (ILs) are a new class of alternative solvents that make ideal non-volatile media for a variety of industrial
processes such as organic synthesis and biocatalysis, as alternative electrolytes, as phases and phase modifications in separation
techniques, and as alternative lubricants. Once the large-scale implementation of ILs begins, the industrial application will
follow. In view of their great stability, they could slip through classical treatment systems to become persistent components
of the environment, where the long-term consequences of their presence are still unknown. Sorption on soils has a critical
effect on the transport, reactivity, and bioavailability of organic compounds in the environment. So far, the IL sorption
mechanism was investigated solely on the basis of batch experiments, which precluded any assessment of the dynamics of the
process. An understanding of the mobility of ILs in soil columns is crucial for an accurate prediction of their fate in the
soil. The aim of this study therefore was to investigate in detail the mobility of selected imidazolium ILs on three soil
types. Moreover, it was decided to study these processes in soils from the coastal region (Gdańsk, Poland), which usually
constitute a very important geochemical compartment, participating in the transport of contaminants on their way to the sea.
Materials and methods The mobility of alkylimidazolium ILs was investigated in columns containing soils from the coastal area. In addition, the
sorption processes in all the soil systems studied were described isothermally and the equilibrium sorption coefficient was
evaluated. The sorption capacities were determined according to OECD guidelines. Sorption dynamics was studied with use of
polypropylene columns (diameter—10 mm, height—100 mm) packed with 10 g of soil. The ionic liquid solution was then injected
into the soil column and left for 24 h to equilibrate. After this, a solution of 0.01 mM CaCl2 was pumped through the column at a rate of 0.3 ml min–1. Effluents were collected from the bottom of the column and analyzed by HPLC.
Results Sorption was strongest on the Miocene silt and the alluvial agricultural soil and weakest on the podsolic soil and Warthanian
glacial till. The K
d value of long-chain ILs was far higher than that of the short-chain ones. Among the substances tested, hydroxylated ILs were
usually more weakly sorbed. Desorption of ILs is inversely correlated with sorption intensity. The experimental results of
the column tests correlate well with those from batch experiments. In the cases of weakly binding soils, ILs were detected
almost immediately in the eluent. The elution profiles of long-chain ILs indicate that these compounds are very strongly sorbed
onto most soils, although certain amounts were transported through the soil. ILs exhibit a certain mobility in soils: in particular,
salts with short and/or hydroxylated side chains are extremely mobile.
Discussion The results indicate a stronger binding of ILs in the first sorption layer; once the first layer is saturated, there are no
more active sites on the soil surface (no free charged groups); hence, there are no more strong electrostatic binding sites,
and dispersive interaction becomes the dominant interaction potential. The influence of the structure of the ILs, especially
the side-chain length was also confirmed: The K
d value of long-chain ILs was far higher than that of the short-chain ones. The long alkyl side chain facilitates dispersive
interactions with soil organic matter and intermolecular binding, and the build-up of a second layer becomes possible. Among
the substances tested, hydroxylated ILs were usually more weakly sorbed. The hydroxyl group in the side chain can alter the
polarity of the compound so strongly that interaction with organic matter hardly occurs; these salts then remain in the aqueous
phase. The experimental results from the column tests correlate well with those from batch tests. In the weakly binding soils
(with low organic matter), the only binding to the soil surface must be via electrostatic interactions, although intermolecular
van der Waals (ionic liquid–ionic liquid) interactions could also be taking place. The elution profile maxima for organic
rich soils are far smaller than for the other soils. In the former, hydrogen bonding, dispersive and π…π interactions play
a more important part than electrostatic interactions. The rapidly “disappearing” maxima of the elution peaks may indicate
that, after elution of ILs from the second layer, it is difficult to extract further sorbed ILs. In the first layer, the ILs
are bound by much stronger electrostatic interactions. To break these bonds, a greater energy is required than that sufficient
to extract ILs from double sorption layers. Results indicate, moreover, that hydrophobic ILs will be sorbed in the first few
centimeters of the soil; migration into the soil will therefore be almost negligible.
Conclusions Sorption of ILs was the strongest in soils with the highest cation exchange capacities and a high organic content. ILs were
also more strongly bound to the first sorption layer. The sorption coefficients of long-chain ILs were far higher than those
of short-chain ones; usually, hydroxylated derivatives were the least strongly sorbed. Results of soil column experiments
to investigate the mobility of ILs in soils correlated well with those from batch tests, and the elution profiles were also
well correlated with organic matter content. The observed rapidly disappearing elution peak maxima probably indicate that,
after elution of the ILs from the second layer, it is difficult to extract further sorbed compounds.
Recommendations and perspectives Obtained results gave an interesting insight into mobility of ionic liquids in soil columns. However, several questions are
now opened. It is therefore necessary to undertake further studies focused on total cycle of ionic liquids in the soil environment.
This should include their evapotrasporation (lysimeter test), bioaccumulation by plants as well as degradation and transformation
processes (chemical, biological, and physical) typically occurring in soils. Moreover, a further risk assessment of ILs is
desirable since this study has indicated that these compounds, especially those with low lipophilicities, are generally mobile
in the soil matrix. It is already known that short-chain ILs are characterized by low toxicities; should they enter the environment,
they will probably migrate within the soil and pose a risk of contamination of surface and ground waters. This topic is relevant
to the audience. Environmental threat of short-chain ionic liquids is currently unknown. From the predictive point of view,
judging on known low acute toxic effects or high polarities of these compounds seems to be not enough to confirm their “environmental
friendliness”. If we are to fully understand the potential environmental effects, one should also have an insight into long-term
biological consequences of these ionic liquids, including chronic toxicity tests, bioaccumulation, and biotransformation rates
as well as stability against natural elimination mechanisms. 相似文献
53.
The aim of study was to estimate how the deadwood of different tree species in various stages of decomposition releases dissolved organic carbon (DOC) and total nitrogen concentration. The deadwood of seven species (Common alder, Common aspen, Common ash, Silver fir, Norway spruce, Common hornbeam, and Silver birch) were selected. Three logs from each species in the third, fourth, and fifth decay classes were chosen for analysis. The investigation was carried out in Czarna Rózga Reserve in Central Poland. The leachate from deadwood was collected in lysimeters. Concentrations of total carbon (TC), inorganic carbon (IC), total organic carbon (TOC), and total nitrogen (TN) were determined. In our investigations, the concentration of TOC measure in filtered water samples was equal to DOC. Additionally, pH and electrical conductivity (EC) values were determined in water samples. The results confirmed the importance of the wood species and the stage of decomposition on the concentration of DOC and TN. Significant differences in the concentration of DOC and TN in leachates released between coniferous and deciduous species were noted. Most DOC and TN were released from decomposing hornbeam and aspen wood, the least DOC, and TN were released into the soil from coniferous species, especially the spruce. 相似文献
54.
Summary The principle of operation of a simple, manually controlled Time Domain Reflectometer (TDR meter) for soil moisture measurements, which operates with a needle pulse of 300 ps rise-time, is described. A block diagram and constructions are also given. Construction of a switchless multiple sensor probe, having an inherent delay reference, is presented. Results of measurements of the soil dielectric constant as related to water content, for soils having different bulk densities, textures and humus content show a high correlation. The results agree closely with other investigators measurements with different, more expensive, TDR instruments. The general principle of microprocessor-controlled TDR operated soil moisture meter is considered.Patent pending 相似文献
55.
Joanna Maaczewska Edyta Kaczorek‐ukowska Roman Wjcik Wojciech Rkawek Andrzej K. Siwicki 《Journal of animal physiology and animal nutrition》2019,103(3):882-893
Nisin, a lantibiotic bacteriocin, has been used for years as a natural food preservative. In addition to its antimicrobial activity, nisin also shows immunomodulatory properties, and the nisin‐producing Lactococcus lactis strain has been successfully tested as a probiotic in weaned piglets. However, the impact of nisin on porcine immune cells has not yet been explored. The objective of the present study was to examine the in vitro immunomodulatory effect of nisin on porcine peripheral blood leucocytes. The whole heparinized blood samples or freshly isolated peripheral blood mononuclear cells (PBMCs) were incubated with different nisin concentrations (0, 1.56, 3.125, 6.25, 12.5, 25 or 50 µg/ml) for 1, 24, 48 or 72 hr. Escherichia coli bacteria were used to stimulate blood phagocytes, while concanavalin A and lipopolysaccharide from E. coli were used as mitogens. Control cells remained unstimulated. MTT colorimetric assay was used to evaluate PBMCs viability and mitogenic response. Phagocyte activity and T‐cell proliferation were measured by flow cytometry. Flow cytometer was also used for immunophenotyping of T cells. Cytokine levels in the culture media were determined using commercial immunoassay (ELISA) kits. The highest concentration of nisin exhibited proliferative activity (p ? 0.05), stimulated interleukin‐1 beta (IL‐1β) and interleukin‐6 (IL‐6) production (both at p ? 0.001), and increased the percentage of CD4+CD8+ T cells (p ? 0.001) among unstimulated leucocytes. After cell stimulation, however, the highest nisin concentration showed antiproliferative activity (p ? 0.05), decreased phagocytic functions (p ? 0.05) and inhibited the synthesis of IL‐6 (time‐ and concentration‐dependent effect). As a typical bacterial product, nisin had a stronger impact on innate immune cells, and its effect on T cells was likely a consequence of the modulation of the activity of antigen‐presenting cells. Nisin may be a good candidate as an immunomodulator in pig breeding. 相似文献
56.
57.
Cells of two Desmodesmus armatus strains (276-4a and 276-4d) grown asynchronously in batch cultures after 24-h treatment revealed different tolerance to chloridazon (photosynthetic herbicide) applied at a concentration of 3.45 mg L−1. To find time- and cell cycle-dependent biochemical reasons leading to such a difference, a population of young autospores of both strains synchronized by a light/dark (14/10) regime were exposed to chloridazon at the initiation of the light period. Chloridazon reduced the growth and number of divisions of cell strain 276-4d. In consequence, at the end of the dark phase the number of released autospores was reduced by 50% compared with the control. In contrast, the growth and reproductive processes of cell strains 276-4a was unaffected. Moreover, chloridazon treatment speeded up cell development, as a result of which the release of autospores took this process observed in the control cells over. There is a relationship between photosynthetic activity response to chloridazon and time-dependent changes in Fe-SOD content and activity. The energy trapped in the reaction centre (RC) was similar in both strains, but the amount of energy absorbed by RCs was twice as high in strain 276-4d as in 276-4a. In consequence, non-photochemical energy dissipation occurring in the cells of 276-4d strain far exceed the value obtained for 276-4a strain. The control cells of both strains differed significantly in the content of FSD 1 and FSD 2 proteins, whereas the differences in Fe-SOD isoforms activities were slight. The 8-fold increase in SOD content in CHD treated cells of strain 276-4a was associated with the transience of photosynthetic efficiency impairment. In CHD treated cells of strain 276-4d, neither activity of Fe-SOD nor FSDs protein content was instantly affected. Different response of developing cells of two Desmodesmus strains to CHD is influenced by the inherent features of cells; the short time required to induce stress adaptive mechanism involving chloroplastic Fe-SOD activity and biosynthesis in the cells of CHD tolerant strain 276-4a seems to play the key role, being an overriding on the high, but not induced in response to stress, FSD protein level and activity in cells of strain 276-4d. 相似文献
58.
Anna M. Olejnik Roman Marecik Wojciech Białas Paweł Cyplik Włodzimierz Grajek 《Water, air, and soil pollution》2010,213(1-4):401-411
Considering the importance of the oral route for human exposure to atrazine, we have investigated the possible effect of this herbicide on the human intestinal cells and the integrity of the epithelial barrier, using Caco-2 cells as the intestinal model in vitro. We evaluated possibile cytotoxic and genotoxic effects of atrazine in concentrations ranging from 1 to 250 μM on the Caco-2 cells at different stages of growth after short- and long-term exposure. Results from the tetrazolium blue (MTT) test and the Trypan blue exclusion assay showed that atrazine cytotoxicity was dose- and time-dependent. Obtained data indicated that atrazine at high concentrations (50 and 250 μM) was able to induce effects on Caco-2 proliferation and viability. Moreover, it was found that the long-term exposure to atrazine at the non-cytotoxic dose caused inhibition of the intestinal cell maturation and decreased the transepithelial electrical resistance, the indicator of the epithelial barrier integrity. Studies on the atrazine genotoxicity determined using the single cell microelectrophoresis assay indicated that atrazine did not induce DNA damages in the Caco-2 cells at concentrations of up to 50 μM, whereas enhancement in the DNA damage was observed at 250 μM. Altogether, our results indicate that atrazine at expected human oral exposure concentrations is not able to induce effects on the Caco-2 cell proliferation and viability, but may suppress the intestinal cell differentiation and reduce the cell monolayer integrity. We suggest that chronic exposure on low levels of atrazine may lead to alteration in the expression of the morphological and functional features of the Caco-2 cells related to the transport and barrier function of small intestinal enterocytes. In consequence, this may lead to alterations in the intestinal absorption process. 相似文献
59.
Łukasz Wolko Wojciech Antkowiak Elżbieta Lenartowicz Jan Bocianowski 《Genetic Resources and Crop Evolution》2010,57(6):801-806
The aim of this study was to identify the group of highly polymorphic microsatellite markers for the identification of six
pear cultivars (P. communis) and two individuals of wild pear (P. pyraster). From among 40 tested SSR markers, 19 were selected to profile genetic diversity in pear genotypes due to high polymorphisms.
These markers showed high heterozygosity levels (0.5–1) and, on average, 6.4 alleles per marker were found. The set of microsatellite
markers employed in this study demonstrated usefulness of microsatellite markers for the identification of pear genotypes.
The examined wild forms were represented in this study by only two individuals of P. pyraster. It can be assumed that these forms were distinctly different from the cultivated pear cultivars. 相似文献
60.
Eugeniusz R. Grela Wojciech Rybiński Renata Klebaniuk Jan Matras 《Genetic Resources and Crop Evolution》2010,57(5):693-701
Thirty-one European accessions of grass pea (Lathyrus sativus L.) originating from Italy, Spain, Northern France, Germany and Poland grown in the same soil-climatic conditions in Poland
were investigated. The morphological traits as well as the seed morphology and nutrient contents were studied. Substantial
differentiation in some morphological characteristics was noticed. The plants could be assigned to two groups: one group comprising
the lines from the Mediterranean basin (Italy and Spain) and the other group containing the accessions from West-central Europe
(Northern France, Germany and Poland). The grass pea plants produced from the seeds obtained from West-central Europe appeared
to be about 10 cm taller than the Mediterranean accessions and had predominantly white flowers. Their seeds were more than
two times smaller than seeds of the accessions of Italian or Spanish origin. There were not noted any considerable differences
in nutrient contents or antinutritional factors in seeds between these two groups of Lathyrus accessions. A negative correlation between β-ODAP and tannin contents (r = −0.379, P ≤ 0.05) and a positive correlation (r = 0.843, P ≤ 0.01) between a tannin content and flower color intensity were found. A white or crème colour was associated with a low
tannin level in the seeds, while the colourful blooming accessions had higher tannin contents. 相似文献