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191.
Mirosław Mleczek Paweł Rutkowski Przemysław Niedzielski Piotr Goliński Monika Gąsecka Tomisław Kozubik 《International journal of phytoremediation》2016,18(11):1086-1095
The aim of the study was to estimate the ability of ten tree and bush species to tolerate and accumulate Cd, Cu, Pb, Zn, and As species [As(III), As(V), and total organic arsenic] in industrial sewage sludge extremely contaminated with arsenic (almost 27.5 g kg?1) in a pot experiment. The premise being that it will then be possible to select the most promising tree/bush species, able to grow in the vicinity of dams where sewage sludge/flotation tailings are used as landfill. Six of the ten tested tree species were able to grow on the sludge. The highest content of total As was observed in Betula pendula roots (30.0 ± 1.3 mg kg?1 DW), where the dominant As species was the toxic As(V). The highest biomass of Quercus Q1 robur (77.3 § 2.6 g) and Acer platanoides (76.0 § 4.9 g) was observed. A proper planting of selected tree species that are able to thrive on sewage sludge/flotation tailings could be an interesting and promising way to protect dams. By utilizing differences in their root systems and water needs, we will be able to reduce the risk of fatal environmental disasters. 相似文献
192.
Aleksandra Kładna Paweł Berczyński Irena Kruk Teresa Piechowska Hassan Y. Aboul‐Enein 《Luminescence》2016,31(6):1201-1206
Isoflavones genistein and daidzein are nonsteroidal phytoestrogens occurring mainly in soybean foods. These phytoestrogens possess estrogenic properties and show a variety of health benefits as anti‐inflammatory agents. However, the mechanism of their action has not been identified in detail. The aim of this study is to characterize the antioxidant powers of genistein, daidzein and daidzein metabolite–equol through their activities to scavenge superoxide anion radical (O?2?), hydroxyl radical (HO?), 2,2–diphenyl–1‐picrylhydrazyl radical (DPPH?) and hydrogen peroxide (H2O2) using chemiluminescence and spectrophotometry techniques. Potassium superoxide in dimethyl sulphoxide (DMSO) and 18‐crown‐6 ether were used as a source of O?2?. Hydroxyl radicals were produced using the Fenton reaction. In free radical assays, genistein had the IC50 values (an amount of antioxidant concentration required to decrease the initial radical concentration by 50%) 0.391 ± 0.012 mM for O?2?, 0.621 ± 0.028 mM for HO? and 1.89 ± 0.16 mM for DPPH?. The IC50 values for daidzein for these free radicals were 1.924 ± 0.011 mM, 0.702 ± 0.012 mM and 2.81 ± 0.03 mM, respectively. Equol was the most active the free radical scavenger with IC50 = 0.451 ± 0.018 mM for HO? and IC50 = 1.36 ± 0.11 mM for DPPH?. All tested compounds exerted a significant effect on the H2O2: IC50 = 18.1 ± 1.1 μM for genistein, IC50 = 2.1 ± 0.5 μM for daidzein, and IC50 = 1.06 ± 0.2 μM for equol. These findings show that genistein, daidzein and equol are effective free radical scavengers and possess high antioxidant power in vitro. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Katarzyna Nowakowska-Domagała Łukasz Mokros Karolina Jabłkowska-Górecka Joanna Grzelińska Tadeusz Pietras 《Chronobiology international》2016,33(10):1351-1358
The study investigates the distribution of chronotypes among alcohol-dependent subjects and the relationship between personality and chronotype. Fifty-eight alcohol-dependent patients and 29 age-matched healthy controls were studied using Ogińska’s Chronotype Questionnaire (ChQ), Eysenck’s Personality Questionnaire – Revised (EPQ-R), Selzer’s Michigan Alcoholism Screening Test (MAST) and a sociodemographic status questionnaire designed by the authors. The alcohol-dependent patients tended to be morning type, based on the morningness–eveningness ChQ scale, with a weakly marked rhythm, based on the distinctness ChQ scale. Preference towards morningness was associated with older age, but no relation between chronotype and severity of alcohol dependence was found. A high amplitude of the rhythm was associated with higher neuroticism. Therefore, despite being in the minority, patients with a distinct circadian rhythm (i.e. with a high amplitude) are at greater risk of mood and anxiety disorders and hence should be given special consideration. 相似文献
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Lipase‐Catalyzed Kinetic Resolution of Novel Antifungal N‐Substituted Benzimidazole Derivatives
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Edyta Łukowska‐Chojnacka Monika Staniszewska Małgorzata Bondaryk Jan K. Maurin Maria Bretner 《Chirality》2016,28(4):347-354
A series of new N‐substituted benzimidazole derivatives was synthesized and their antifungal activity against Candida albicans was evaluated. The chemical step included synthesis of appropriate ketones containing benzimidazole ring, reduction of ketones to the racemic alcohols, and acetylation of alcohols to the esters. All benzimidazole derivatives were obtained with satisfactory yields and in relatively short times. All synthesized compounds exhibit significant antifungal activity against Candida albicans 900028 ATCC (% cell inhibition at 0.25 μg concentration > 98%). Additionally, racemic mixtures of alcohols were separated by lipase‐catalyzed kinetic resolution. In the enzymatic step a transesterification reaction was applied and the influence of a lipase type and solvent on the enantioselectivity of the reaction was studied. The most selective enzymes were Novozyme SP 435 and lipase Amano AK from Pseudomonas fluorescens (E > 100). Chirality 28:347–354, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
198.
Anticonvulsant Activity of Enantiomeric N‐trans‐Cinnamoyl Derivatives of 2‐Aminopropan‐1‐ols and 2‐Aminobutan‐1‐ols
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Agnieszka Gunia‐Krzyżak Ewa Żesławska Wojciech Nitek Justyna Popiół Henryk Marona 《Chirality》2016,28(6):482-488
Epilepsy, one of the most frequent neurological disorders, is still insufficiently treated in about 30% of patients. As a consequence, identification of novel anticonvulsant agents is an important issue in medicinal chemistry. In the present article we report synthesis, physicochemical, and pharmacological evaluation of N‐trans‐cinnamoyl derivatives of R and S‐2‐aminopropan‐1‐ol, as well as R and S‐2‐aminobutan‐1‐ol. The structures were confirmed by spectroscopy and for derivatives of 2‐aminopropan‐1‐ols the configuration was evaluated by means of crystallography. The investigated compounds were tested in rodent models of seizures: maximal electroshock (MES) and subcutaneous pentetrazol test (scPTZ), and also in a rodent model of epileptogenesis: pilocarpine‐induced status prevention. Additionally, derivatives of 2‐aminopropan‐1‐ols were tested in benzodiazepine‐resistant electrographic status epilepticus rat model as well as in vitro for inhibition of isoenzymes of cytochrome P450. All of the tested compounds showed promising anticonvulsant activity in MES. For R(–)‐(2E)‐N‐(1‐hydroxypropan‐2‐yl)‐3‐phenylprop‐2‐enamide pharmacological parameters were found as follows: ED50 = 76.7 (68.2–81.3) mg/kg (MES, mice i.p., time = 0.5 h), ED50 = 127.2 (102.1–157.9) mg/kg (scPTZ, mice i.p., time = 0.25 h), TD50 = 208.3 (151.4–230.6) mg/kg (rotarod, mice i.p., time = 0.25 h). Evaluation in pilocarpine status prevention proved that all of the reported compounds reduced spontaneous seizure activity and act as antiepileptogenic agents. Both enantiomers of 2‐aminopropan‐1‐ols did not influence cytochrome P450 isoenzymes activity in vitro and are likely not to interact with CYP substrates in vivo. Chirality 28:482–488, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
199.
We investigated the effects of several tree species on dehydrogenase and urease activities in soils derived from two different parent materials (glaciofluvial sand and loess) in forested areas in southern Poland. We hypothesized that coniferous forests (pine, spruce) alter the soil cation exchange capacity (CEC) and decrease soil pH and, therefore, might decrease soil enzyme activities compared with broadleaf species growing on similar soils. Eight paired plots (12 × 12 m) were established on glaciofluvial sand in pine (Pinus sylvestris) + oak (Quercus robur) and spruce (Picea abies) + pine stands, as well as on loess-derived soils: beech (Fagus sylvatica) + pine and hornbeam (Carpinus betulus) + pine stands. Each plot was a 4 × 4 m grid with 16 sampling points. In soil samples pH, soil texture, and organic carbon, nitrogen, base cation contents, dehydrogenase and urease activities were determined. On both parent materials, the soil pH was lower under coniferous species than under broadleaf species. The acidifying effect of tree species on sandy soil was in the order of spruce = pine > oak, while that on loess was pine > beech > hornbeam. Hornbeam and oak increased the soil pH and stimulated enzyme activity in the soil. The content of fine fraction enhanced potential enzyme activities in soils, thus the loess soils had greater dehydrogenase and urease activity. The results suggest that pine stores more soil organic C in association with silt increasing the pool of stabilized soil organic C. 相似文献
200.
Łukasz Mokros Michał Seweryn Karbownik Katarzyna Nowakowska-Domagała Janusz Szemraj Łukasz Wieteska Karol Woźniak 《Biological Rhythm Research》2016,47(6):865-871
Background: There is barely any evidence of antipsychotic drugs affecting the molecular clockwork in human, yet it is suggested that clock genes are associated with dopaminergic transmission, i.e. the main target of this therapeutics. We decided to verify if haloperidol and olanzapine affect expression of CLOCK, BMAL1, PER1 and CRY1 in a human central nervous system cell line model. Methods: U-87MG human glioblastoma cell line was used as an experimental model. The cells were incubated with or without haloperidol and olanzapine in the concentration of 5 and 20 μM for 24 h. Real-time quantitative polymerase chain reaction with the ΔCT analysis was used to examine the effect of haloperidol and olanzapine on the mRNA expression of the genes. Results: At 5 μM, haloperidol decreased expression of CRY1 almost 20-fold. There was nearly a 1.5-fold increase in expression of PER1. Considering the 20 μM haloperidol concentration and both olanzapine concentrations, no other statistically significant effect was observed. Conclusions: At certain concentration, haloperidol seems to affect expression of particular clock genes in a human central nervous system cell line model, yet mechanism underlying this phenomenon remains elusive. 相似文献