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221.
222.
Zeynep Alkan Alkaya Halil İlkimen Yasemin Kaygısız Metin Bülbül Tuncay Tunç 《Journal of enzyme inhibition and medicinal chemistry》2017,32(1):231-239
A novel proton transfer compound (SMHABT)+(HDPC)? (1) obtained from 2-amino-6-sulfamoylbenzothiazole (SMABT) and 2,6-pyridinedicarboxylic acid (H2DPC) and its Fe(III), Co(II), Ni(II) complexes (2–4), and Fe(II) complex of SMABT (5) have been prepared and characterized by spectroscopic techniques. Additionally, single crystal X-ray diffraction techniques were applied to complexes (2–4). All complexes (2–4) have distorted octahedral conformations and the structure of 5 might be proposed as octahedral according to spectral and analytical results. All compounds, including acetazolamide (AAZ) as the control compound, were also evaluated for their in vitro inhibition effects on human hCA I and hCA II for their hydratase and esterase activities. The synthesized compounds have remarkable inhibitory activities on hCA I and hCA II. Especially, the inhibition potentials of the salt and the metal complexes (1–5) are comparable with AAZ. Inhibition data have been analyzed by using a one-way analysis of variance for multiple comparisons (p?.0001). 相似文献
223.
Phenolic Composition,Anti‐Inflammatory,Antioxidant, and Antimicrobial Activities of Alchemilla mollis (Buser) Rothm.
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The current study was designed to evaluate the antioxidant, anti‐inflammatory and antimicrobial activities of Alchemilla mollis (Buser ) Rothm . (Rosaceae) aerial parts extracts. Chemical composition was analyzed by spectrophotometric and chromatographic (HPLC) techniques. The antioxidant properties assessed included DPPH· and ABTS·+ radical scavenging, β‐carotene‐linoleic acid co‐oxidation assay. Antimicrobial activity was evaluated with disc diffusion and micro dilution method. In order to evaluate toxicity of the extracts, with the sulforhodamine B colorimetric assay L929 cell line (mouse fibroblast) was used. The anti‐inflammatory activities of the potent antioxidant extracts (methanol, 70% methanol, and water extracts) were determined by measuring the inhibitory effects on NO production and pro‐inflammatory cytokine TNF‐α levels in lipopolysaccharide stimulated RAW 264.7 cells. 70% methanol and water extracts which were found to be rich in phenolic compounds (184.79 and 172.60 mg GAE/g extract) showed higher antioxidant activity. Luteolin‐7‐O‐glucoside was the main compound in the extracts. Ethyl acetate and 70% methanol extracts showed higher antibacterial activity against Staphylococcus aureus and Salmonella enteritidis with MIC value of 125 μg/ml. 70% methanol extract potentially inhibited the NO and TNF‐α production (18.43 μm and 1556.22 pg/ml, respectively, 6 h). 相似文献
224.
S. Çöçü S. Uranbey A. İpek K.M. Khawar E.O. Sarihan M.D. Kaya İ. Parmaksiz S. Özcan 《Biologia Plantarum》2004,48(3):449-451
Hypocotyl, cotyledon and cotyledonary node explants of Calendula officinalis L were cultured on Murashige and Skoog (MS) media supplemented with various concentrations of thidiazuron (TDZ), kinetin (KIN), -naphthaleneacetic acid (NAA) and indole-3-butyric acid (IBA) to induce adventitious shoot regeneration and micropropagation. The highest frequency of adventitious shoot regeneration was achieved from hypocotyl and cotyledon explants on MS media supplemented with 0.75 mg dm–3 TDZ and either 0.25 or 0.50 mg dm–3 IBA. Efficient in vitro clonal propagation was also induced from cotyledonary nodes on a range of media supplemented with 0.75 mg dm–3 TDZ and 0.05 mg dm–3 NAA or 2 mg dm–3 KIN and 1 mg dm–3 NAA. Regenerated shoots were excised and rooted in MS medium supplemented with 1 mg dm–3 NAA. The rooted plantlets were finally transferred to pots. 相似文献
225.
Life history of Euseius scutalis feeding on citrus red mite Panonychus citri at various temperatures
The aim of this study was todetermine the biology and reproductivepotential of Euseius scutalis(Athias-Henriot) (Acari: Phytoseiidae) atvarious temperatures. These data are of valuein relation to mass rearing and the developmentof population dynamics models. The developmenttime, survival and fecundity of E.scutalis were determined at 20, 25 and30 ± 1 °C, 65 ± 10% RH and 16:8photoperiod. Total development times of E.scutalis were 6.7, 4.9 and 4.2 days at 20, 25and 30 ± 1 °C, respectively, using adiet of all life stages of the spider mite Panonychus citri (McGregor) (Acari:Tetranychidae). In general, preoviposition andpostoviposition periods of E. scutaliswere shortened as temperature increased, butthe oviposition period was longer at 25 °C than at 20 and 30 °C. Theshortest survival time of E. scutalis, at30 °C, was 10.1 days, followed by 23.7days and 28.6 days at 20 and 25 °C,respectively. Mated females laid on average1.1, 1.4 and 1.7 eggs per female per day and21.5, 39.7 and 17.1 eggs over their entire lifetime at 20, 25 and 30 °C, respectively.The sex ratios of E. scutalis were2.11/1, 2.24/1 and 2.11/1 female/male at 20, 25and 30 °C, respectively. The intrinsicrate of natural increase (r
m) increasedwith rising temperatures from 0.166 at 20 °C to 0.295 females/female/day at 30 °C. The net reproductive rate (R
0)was highest at 25 °C (26.03females/female) and lowest at 30 °C(12.95 females/female). Mean generation time(T
0) was longest at 25 °C (17.50days) and shortest (9.53 days) at 30 °C. 相似文献
226.
İlhami Gülçin Andrea Scozzafava Zeynep Koksal Fikret Turkan Songül Çetinkaya 《Journal of enzyme inhibition and medicinal chemistry》2016,31(6):1698-1702
Rosmarinic acid (RA) is a natural polyphenol contained in many aromatic plants with promising biological activities. Carbonic anhydrases (CAs, EC 4.2.1.1) are widespread and intensively studied metalloenzymes present in higher vertebrates. Acetylcholinesterase (AChE, E.C. 3.1.1.7) is intimately associated with the normal neurotransmission by catalysing the hydrolysis of acetylcholine to acetate and choline and acts in combination with butyrylcholinesterase (BChE) to remove acetylcholine from the synaptic cleft. Lactoperoxidase (LPO) is an enzyme involved in fighting pathogenic microorganisms, whereas glutathione S-transferases (GSTs) are dimeric proteins present both in prokaryotic and in eukaryotic organisms and involved in cellular detoxification mechanisms. In the present study, the inhibition effects of rosmarinic acid on tumour-associated carbonic anhydrase IX and XII isoenzymes, AChE, BChE, LPO and GST enzymes were evaluated. Rosmarinic acid inhibited these enzymes with Kis in the range between micromolar to picomolar. The best inhibitory effect of rosmarinic acid was observed against both AChE and BChE. 相似文献
227.
Fatih Çağlar Çelikezen Başak Toğar Fatma Betül Özgeriş Mehmet Sait İzgi Hasan Türkez 《Cytotechnology》2016,68(4):821-827
Boron compounds have an ability of supporting antioxidant properties in human and animal tissues. Lithium metaborate dihydrate (LiBO2·2H2O; LMD) is commonly used in nonlinear optic materials, cellular phones and pagers. But, there are limited data on the genotoxic and antioxidant effects of LMD in cultured human whole blood cells. The aim of this study was to evaluate for the genotoxicity and antioxidant/oxidant activity of LMD on human whole blood lymphocytes (n = 5). LMD was applied at various concentrations (0–1,280 µg/ml) to cultured blood samples. Antioxidant/oxidant activity was evaluated by measuring the total oxidant status (TOS) and total antioxidant capacity levels. Micronuclei and chromosomal aberration tests were used in genotoxicity studies. Our results clearly revealed that all tested concentrations of LMD were found to be non-genotoxic when compared to that of the control group. In addition, LMD exhibited antioxidant activities at low concentrations. In addition the TOS levels were not changed at all concentrations of LMD. Consequently, our results clearly demonstrated that LMD is non-genotoxic and it has an important antioxidant potential in vitro. 相似文献
228.
Cy‐preds: An algorithm and a web service for the analysis and prediction of cysteine reactivity
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Cysteine (Cys) is a critically important amino acid, serving a variety of functions within proteins including structural roles, catalysis, and regulation of function through post‐translational modifications. Predicting which Cys residues are likely to be reactive is a very sought after feature. Few methods are currently available for the task, either based on evaluation of physicochemical features (e.g., pKa and exposure) or based on similarity with known instances. In this study, we developed an algorithm (named HAL‐Cy) which blends previous work with novel implementations to identify reactive Cys from nonreactive. HAL‐Cy present two major components: (i) an energy based part, rooted on the evaluation of H‐bond network contributions and (ii) a knowledge based part, composed of different profiling approaches (including a newly developed weighting matrix for sequence profiling). In our evaluations, HAL‐Cy provided significantly improved performances, as tested in comparisons with existing approaches. We implemented our algorithm in a web service (Cy‐preds), the ultimate product of our work; we provided it with a variety of additional features, tools, and options: Cy‐preds is capable of performing fully automated calculations for a thorough analysis of Cys reactivity in proteins, ranging from reactivity predictions (e.g., with HAL‐Cy) to functional characterization. We believe it represents an original, effective, and very useful addition to the current array of tools available to scientists involved in redox biology, Cys biochemistry, and structural bioinformatics. Proteins 2016; 84:278–291. © 2015 Wiley Periodicals, Inc. 相似文献
229.
The mechanisms of aluminum (Al) neurotoxicity is of increasing interest. Al compounds are known to produce neurological and
behavioral abnormalities in some mammalian species. The present study was designed to determine the effects of Al chloride
on the skilled motor performance in mice on the rota-rod treadmill. Al chloride, depending on the duration of treatment, produced
an impairment of the motor coordination ability in mice. 相似文献
230.
Cancer is a serious problem affecting the health of all human societies. Chemotherapy refers to the use of drugs to kill cancer or the origin of cancer. In the past three decades, researchers have studied about proteins and their roles in the production of cancer cells. Glutathione S-transferases (GSTs) are a superfamily of enzymes that play a key role in cellular detoxification, protecting against reactive electrophiles attacks, including chemotherapeutic agents. Glutathione reductase (GR) is an important antioxidant enzyme involved in protecting the cell against oxidative stress. In this current study, GST and GR enzymes were purified from human erythrocytes using affinity chromatography. GR was obtained with a specific activity of 5.95 EU/mg protein and a 52.38 % yield. GST was obtained with a specific activity of 4.88 EU/mg protein and a 74.88 % yield. The effect of fluorophenylthiourea derivatives on the purified enzymes was investigated. Afterward, KI values were found to range from 23.04±4.37 μM–59.97±13.45 μM for GR and 7.22±1.64 μM–41.24±2.55 μM for GST. 1-(2,6-difluorophenyl)thiourea was showed the best inhibition effect for both GST and GR enzymes. The relationships of inhibitors with 3D structures of GST and GR were explained by molecular docking studies. 相似文献