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An infrared spectroscopic method for quantitative analysis of fatty alcohols and fatty acid esters in machinery oils.

https://arctichealth.org/en/permalink/ahliterature9130
Source
Anal Bioanal Chem. 2005 Sep;383(2):305-11
Publication Type
Article
Date
Sep-2005
Author
Pekka Vähäoja
Jani Närhi
Toivo Kuokkanen
Outi Naatus
Jorma Jalonen
Sulo Lahdelma
Author Affiliation
Department of Chemistry, University of Oulu, P.O. Box 3000, 90014, Oulu, Finland. Pekka.Vahaoja@oulu.fi
Source
Anal Bioanal Chem. 2005 Sep;383(2):305-11
Date
Sep-2005
Language
English
Publication Type
Article
Keywords
Carbon Disulfide - chemistry
Carbon Tetrachloride - chemistry
Comparative Study
Dodecanol - analysis
Esters - analysis
Fatty Acids - analysis
Fatty Alcohols - analysis
Palmitates - analysis
Plant Oils - chemistry
Research Support, Non-U.S. Gov't
Solvents - chemistry
Spectrophotometry, Infrared - methods
Stearates - analysis
Volatilization
Abstract
A new infrared spectroscopic method suitable for determining total fatty alcohol and fatty acid ester concentrations in industrial oils has been developed. Oil samples were diluted with toluene (1:3 w/w), the toxicity and volatility of which are relatively low compared with more commonly used IR solvents, like carbon tetrachloride or carbon disulfide. Mixture standards were prepared from dodecanol, tetradecanol, octadecanol, methyl stearate and methyl palmitate. Some analytical and statistical tests were performed on the developed method. The recoveries and the repeatability of the method proved to be sufficient for the quantitative determination of fatty alcohol and fatty acid ester additives in industrial oils. Reproducibility testing in another laboratory also produced satisfactory results. The developed method also proved to be relatively quick and simple. This method was developed to satisfy industry's need to determine the concentrations of these oil additives, and it has already been applied successfully in machinery oil analysis.
PubMed ID
16132128 View in PubMed
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Antidiabetic effects of Justicia spicigera Schltdl (Acanthaceae).

https://arctichealth.org/en/permalink/ahliterature122422
Source
J Ethnopharmacol. 2012 Sep 28;143(2):455-62
Publication Type
Article
Date
Sep-28-2012
Author
Rolffy Ortiz-Andrade
Angel Cabañas-Wuan
Víctor E Arana-Argáez
Angel Josabad Alonso-Castro
Rocio Zapata-Bustos
Luis A Salazar-Olivo
Fabiola Domínguez
Marco Chávez
Candy Carranza-Álvarez
Alejandro García-Carrancá
Author Affiliation
Facultad de Química, Universidad Autónoma de Yucatán, Mérida, Yucatán, México. rolffy@uady.mx
Source
J Ethnopharmacol. 2012 Sep 28;143(2):455-62
Date
Sep-28-2012
Language
English
Publication Type
Article
Keywords
3T3 Cells
4-Chloro-7-nitrobenzofurazan - analogs & derivatives - metabolism
Acanthaceae
Adipocytes - drug effects - metabolism
Animals
Antioxidants - pharmacology - therapeutic use
Benzothiazoles - metabolism
Cell Survival - drug effects
Cells, Cultured
Deoxyglucose - analogs & derivatives - metabolism
Diabetes Mellitus, Experimental - drug therapy - metabolism
Ethanol - chemistry
Glucose - metabolism
Glucose Tolerance Test
Humans
Hypoglycemic Agents - pharmacology - therapeutic use
Kaempferols - analysis
Male
Mice
Phytotherapy
Plant Extracts - pharmacology - therapeutic use
Plant Leaves
Rats
Rats, Wistar
Solvents - chemistry
Sulfonic Acids - metabolism
Abstract
Justicia spicigera is a plant species used for the Teenak (Huesteca Potosina) and Mayan (Yucatan peninsula) indigenous for the empirical treatment of diabetes, infections and as stimulant.
To evaluate the cytotoxicity, antioxidant and antidiabetic properties of J. spicigera.
The effects of ethanolic extracts of J. spicigera (JSE) on the glucose uptake in insulin-sensitive and insulin-resistant murine 3T3-F442A and human subcutaneous adipocytes was evaluated. The antioxidant activities of the extract of JSE was determined by ABTS and DPPH methods. Additionally, it was evaluated the antidiabetic properties of JSE on T2DM model.
JSE stimulated 2-NBDG uptake by insulin-sensitive and insulin-resistant human and murine adipocytes in a concentration-dependent manner with higher potency than rosiglitazone 1mM. JSE showed antioxidant effects in vitro and induced glucose lowering effects in normoglycemic and STZ-induced diabetic rats.
The antidiabetic effects of administration of J. spicigera are related to the stimulation of glucose uptake in both insulin-sensitive and insulin-resistant murine and human adipocytes and this evidence justify its empirical use in Traditional Medicine. In addition, J. spicigera exerts glucose lowering effects in normoglycemic and STZ-induced diabetic rats.
PubMed ID
22819688 View in PubMed
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Antioxidant and angiotensin converting enzyme (ACE) inhibitory activities of ethanol extract and pure flavonoids from Adinandra nitida leaves.

https://arctichealth.org/en/permalink/ahliterature141270
Source
Pharm Biol. 2010 Dec;48(12):1432-8
Publication Type
Article
Date
Dec-2010
Author
Benguo Liu
Jiguo Yang
Yuxiang Ma
Erdong Yuan
Chungang Chen
Author Affiliation
School of Food Science, Henan Institute of Science and Technology, Xinxiang 453003, China. zzgclbg@126.com
Source
Pharm Biol. 2010 Dec;48(12):1432-8
Date
Dec-2010
Language
English
Publication Type
Article
Keywords
Angiotensin-Converting Enzyme Inhibitors - isolation & purification - pharmacology
Antioxidants - isolation & purification - pharmacology
Chromatography, High Pressure Liquid
Ethanol - chemistry
Flavonoids - isolation & purification - pharmacology
Humans
Plant Extracts - pharmacology
Plant Leaves
Solvents - chemistry
Theaceae - chemistry
Abstract
Adinandra nitida Merr. ex. H.L. Li (Theaceae) is an indigenous plant in south China. Its leaves have been reported to have many curative effects such as reducing blood pressure, as well as antibacterial, antioxidant, and analgesic properties, which could be used in foods and medicines.
The antioxidant and angiotensin converting enzyme (ACE) inhibitory activities of the main flavonoids and ethanol extract (EE) of A. nitida leaves were investigated for the first time.
The main flavonoids of A. nitida leaves (camellianin A, camellianin B) were prepared and their contents in EE were determined by HPLC. The antioxidant activities of the samples were measured by DPPH radical scavenging assay and Rancimat test. The ACE inhibitory activities of the samples were carried out by using an assay kit with hippuryl-glycyl-glycine as substrate.
The contents of camellianin A, camellianin B and apigenin in EE were determined as 41.98, 2.67, and 1.73%, respectively. The antioxidant activities of the flavonoids were far lower than that of EE in DPPH radical scavenging and Rancimat assays. However, the ACE-inhibitory activities of camellianin A, camellianin B and apigenin were higher than that of EE.
The flavonoid content of EE was more than 45%. The high activities of EE in DPPH scavenging and Rancimat assay could be mainly attributed to compounds other than flavonoids. However, the ACE-inhibitory activity of EE could be mainly attributed to the presence of the flavonoids.
PubMed ID
20738217 View in PubMed
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[Effect of incubation medium dielectric permeability on enzymatic activity of functionally different ATPases of smooth muscles]

https://arctichealth.org/en/permalink/ahliterature11017
Source
Ukr Biokhim Zh. 1997 Jul-Aug;69(4):9-17
Publication Type
Article
Author
N N Slinchenko
T T Taran
S A Kosterin
Author Affiliation
A.V.Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv.
Source
Ukr Biokhim Zh. 1997 Jul-Aug;69(4):9-17
Language
Russian
Publication Type
Article
Keywords
Acetone - chemistry - pharmacology
Animals
Ca(2+) Mg(2+)-ATPase - metabolism
Catalysis
Cell Membrane - drug effects - enzymology
Cryoprotective Agents - chemistry - pharmacology
Dimethyl Sulfoxide - chemistry - pharmacology
Dioxanes - chemistry - pharmacology
Electrostatics
English Abstract
Ethanol - chemistry - pharmacology
Female
In Vitro
Muscle, Smooth - drug effects - enzymology
Myometrium - enzymology
Myosins - metabolism
Solvents - chemistry - pharmacology
Swine
Abstract
Some organic solvents (2-10%) have been comparatively studied for their effect on purified transporting Ca2+, Mg(2+)-ATPase, solubilized from the plasma membrane of smooth muscle cells and on actomyosine ATPase of the smooth muscle. The inhibiting effect of solvents on the initial maximum specific activity of Ca2+, Mg(2+)-ATPase corresponds to the sequence dioxane > acetone > ethanol > dimethyl sulfoxide (DMSO). Like the case with Ca2+, Mg(2+)-ATPase, dioxane inhibits actomyosine ATPase; acetone, ethanol and DMSO stimulate ATP-hydrolase reaction which is catalyzed by the complex of contractile proteins. It is proved that the effect of the decrease of ATPase activity with decrease of incubation medium polarity is exceptionally determined by the value of incubation medium the dielectric permeability. This effect is independent of chemical nature of organic solvents which were used with the aim to obtain the corresponding values of D. It is supposed that the cause of activity inhibition of solubilized transporting Ca2+, Mg(2+)-ATPase under the effect of dioxane, acetone, ethanol and inhibition of activity of actomyosine ATPase as affected by dioxane is mainly connected with the increase of electrostatical interaction between opposity charged active centre of ATPase and the product (products) of ATP-hydrolase reaction (Mg ADP-, HPO4(2-)), which is induced by the decrease of incubation medium polarity (the decrease of D value). Stimulating effect of acetone and ethanol on actomyosine ATPase is probably determined by superposition of two components: that connected with direct effect of these solvents on the protein catalyst (interaction with enzyme with the future break of hydrogen and hydrophobic bonds in the protein and its "fluffing") and "electrostatic component" determined by the change of D value of the incubation medium. Possible role of electrostatic interactions between ATPases and reagents as the factor of non-specific control of catalytic activity of these enzymes is discussed.
PubMed ID
9583116 View in PubMed
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Effect of initial voltage ramp on separation efficiency in non-aqueous capillary electrophoresis with ethanol as background electrolyte solvent.

https://arctichealth.org/en/permalink/ahliterature9240
Source
J Chromatogr A. 2005 Mar 11;1068(1):107-14
Publication Type
Article
Date
Mar-11-2005
Author
Sami Palonen
Matti Jussila
Marja-Liisa Riekkola
Author Affiliation
Laboratory of Analytical Chemistry, Department of Chemistry, P.O. Box 55, FI-00014 University of Helsinki, Helsinki, Finland. sami.palonen@helsinki.fi
Source
J Chromatogr A. 2005 Mar 11;1068(1):107-14
Date
Mar-11-2005
Language
English
Publication Type
Article
Keywords
Electrolytes - chemistry
Electrophoresis, Capillary - methods
Ethanol - chemistry
Research Support, Non-U.S. Gov't
Solvents - chemistry
Abstract
Band broadening at high electric field strengths in capillary electrophoresis (CE), especially in wide capillaries, is often attributed to radial temperature gradients in the interior of the capillary caused by Joule heating. In some cases, however, a major cause of the lower separation efficiency could be the abrupt application of high electric field strength. We show that, with ethanol as background electrolyte solvent, initial abrupt voltage application introduces band broadening, which is especially pronounced in wider capillaries at high electric field and ionic strengths. With an appropriate initial voltage ramp this effect can be avoided. The effect of different voltage ramp up times on the separation efficiency of some anionic analytes was investigated with 50, 75 and 100 microm I.D. capillaries at field strengths of 1000-2000 V cm(-1). The results suggest that the band broadening associated with abrupt voltage application is of thermal origin and probably related to thermal volume expansion of the sample and background electrolyte solutions. The plate numbers calculated with a plate height model were in good agreement with the experimental values when a sufficiently long voltage ramp was employed. The dispersion due to axial temperature gradients was found to be very small under the experimental conditions used.
PubMed ID
15844548 View in PubMed
Less detail

Formation and analysis of tobacco-specific N-nitrosamines.

https://arctichealth.org/en/permalink/ahliterature22941
Source
Crit Rev Toxicol. 1996;26(2):121-37
Publication Type
Article
Date
1996
Author
K D Brunnemann
B. Prokopczyk
M V Djordjevic
D. Hoffmann
Author Affiliation
Naylor Dana Institute for Disease Prevention, American Health Foundation, Valhalla, NY 10595, USA.
Source
Crit Rev Toxicol. 1996;26(2):121-37
Date
1996
Language
English
Publication Type
Article
Keywords
Air Pollution, Indoor - analysis
Carcinogens - analysis - chemistry
Chromatography, Gas
Differential Thermal Analysis
Humans
Male
Nicotine - analysis
Nitrosamines - analysis - chemistry
Plants, Toxic
Research Support, U.S. Gov't, P.H.S.
Saliva - chemistry
Solvents - chemistry
Tobacco - chemistry
Tobacco Smoke Pollution - analysis
Tobacco, Smokeless - chemistry
Abstract
Chemical-analytical studies during the past 4 years led to several new observations on the formation of tobacco-specific N-nitrosamines (TSNA) and their occurrence in smokeless tobacco, mainstream smoke (MS), and sidestream smoke (SS) of American and foreign cigarettes. When snuff was extracted by means of supercritical fluid extraction with carbon dioxide containing 10% methanol, analysis of this material confirmed that the extraction with organic solvents had been partially incomplete. Epidemiological studies in the northern Sudan showed a high risk for oral cancer for users of toombak, a home-made oral snuff. Toombak contains 100-fold higher levels of TSNA than commercial snuff in the U.S. and Sweden. The TSNA content in the saliva of toombak dippers is at least ten times higher than that reported in the saliva of dippers of commercial snuff. Biomarker studies have shown corresponding high levels of hemoglobin adducts with metabolites of NNN and NNK as well as for urinary metabolites of NNK. These data supported the epidemiological findings. The analyses of MS of U.S. and foreign cigarettes smoked under FTC conditions revealed comparable data for the smoke of nonfilter cigarettes and filter cigarettes except in the case of low- and ultralow-yield cigarettes, which showed reduced TSNA yields. The MS of cigarettes made from Burley or dark tobacco is exceptionally high in TSNA, primarily because of the high nitrate content of those tobacco types. Taking puffs of larger volume and drawing puffs more frequently, practices observed among most smokers of cigarettes with low nicotine yield, results in high TSNA values in the MS. The formation of the lung carcinogen NNK is favored during the smoldering of cigarettes, between puffs, when SS is generated. Consequently, in most samples from indoor air polluted with environmental tobacco smoke (ETS), the highest concentration of an individual TSNA is that of NNK. When nonsmokers had remained for up to 2 h in a test laboratory with high ETS pollution, they excreted measurable amounts of NNK metabolites in the urine, indicative of the uptake of TSNA.
PubMed ID
8688156 View in PubMed
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Full four-component relativistic calculations of the one-bond 77Se-13C spin-spin coupling constants in the series of selenium heterocycles and their parent open-chain selenides.

https://arctichealth.org/en/permalink/ahliterature258994
Source
Magn Reson Chem. 2014 May;52(5):214-21
Publication Type
Article
Date
May-2014
Author
Yury Yu Rusakov
Irina L Rusakova
Leonid B Krivdin
Source
Magn Reson Chem. 2014 May;52(5):214-21
Date
May-2014
Language
English
Publication Type
Article
Keywords
Heterocyclic Compounds - chemistry
Isotopes
Molecular Structure
Organoselenium Compounds - chemistry
Quantum Theory
Selenium - chemistry
Solvents - chemistry
Abstract
Four-component relativistic calculations of (77)Se-(13)C spin-spin coupling constants have been performed in the series of selenium heterocycles and their parent open-chain selenides. It has been found that relativistic effects play an essential role in the selenium-carbon coupling mechanism and could result in a contribution of as much as 15-25% of the total values of the one-bond selenium-carbon spin-spin coupling constants. In the overall contribution of the relativistic effects to the total values of (1)J(Se,C), the scalar relativistic corrections (negative in sign) by far dominate over the spin-orbit ones (positive in sign), the latter being of less than 5%, as compared to the former (ca 20%). A combination of nonrelativistic second-order polarization propagator approach (CC2) with the four-component relativistic density functional theory scheme is recommended as a versatile tool for the calculation of (1)J(Se,C). Solvent effects in the values of (1)J(Se,C) calculated within the polarizable continuum model for the solvents with different dielectric constants (e 2.2-78.4) are next to negligible decreasing negative (1)J(Se,C) in absolute value by only about 1?Hz. The use of the locally dense basis set approach applied herewith for the calculation of (77)Se-(13)C spin-spin coupling constants is fully justified resulting in a dramatic decrease in computational cost with only 0.1-0.2-Hz loss of accuracy.
PubMed ID
24549877 View in PubMed
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[Methodological aspects of the assessment of phytotoxicic properties of ice-melter reagents].

https://arctichealth.org/en/permalink/ahliterature290147
Source
Gig Sanit. 2016; 95(8):773-8
Publication Type
Journal Article
Author
A V Sbitnev
M A Vodianova
I A Kriatov
L G Donerian
I S Evseeva
O V Ushakova
D I Ushakov
I S Matveeva
O M Rodionova
Source
Gig Sanit. 2016; 95(8):773-8
Language
Russian
Publication Type
Journal Article
Keywords
Environmental Monitoring - methods
Environmental Pollution - adverse effects - analysis - prevention & control
Freezing
Humans
Ice
Plants - drug effects
Russia
Snow
Sodium Chloride - chemistry - toxicity
Soil Pollutants - chemistry - toxicity
Solvents - chemistry
Toxicological Phenomena
Transportation
Abstract
One of the main criteria which determine the possibility of the use of a particular type of ice-melter reagents (IMR) is the degree of their safety for the environment and human health, which is reflected in the establishment of safe doses and concentrations. In this regard, the current area of research is to improve the ecological and epidemiological principles of risk assessment of modern types of anti-icing agents. Currently available data concerning monitoring soil studies and the snow held in various cities of Russia, show that there is a process of accumulation of the main components of IMR - sodium and chlorine ions in the areas related to the roadway. The article is designated a problem of existing methodological approaches to the assessment of the phytotoxic impact in the investigation of anti-icing agents in the laboratory. There was executed the comparative characteristics of the results of the preliminary pilot studies on the phytotoxic properties of IMR under using different substrates for germination of seeds - soil and filter paper. The data obtained are characterized by differences in the degree of phytotoxic action of the same species depending upon ice-melter reagents methodical setting circuit laboratory experiment. As a result, there was shown the imperfection of the existing method of rapid analysis in relation to ice-melter materials (IMM).
PubMed ID
29430905 View in PubMed
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Peak dispersion and contributions to plate height in nonaqueous capillary electrophoresis at high electric field strengths: propanol as background electrolyte solvent.

https://arctichealth.org/en/permalink/ahliterature9719
Source
Electrophoresis. 2003 May;24(10):1565-76
Publication Type
Article
Date
May-2003
Author
Sami Palonen
Simo P Porras
Matti Jussila
Marja-Liisa Riekkola
Author Affiliation
Department of Chemistry, University of Helsinki, Helsinki, Finland. sami.palonen@helsinki.fi
Source
Electrophoresis. 2003 May;24(10):1565-76
Date
May-2003
Language
English
Publication Type
Article
Keywords
1-Propanol - chemistry
Diffusion
Electricity
Electrolytes - chemistry
Electrophoresis, Capillary - methods
Research Support, Non-U.S. Gov't
Solvents - chemistry
Abstract
Peak dispersion effects in nonaqueous capillary electrophoretic separations of aromatic anionic analytes were investigated in a propanolic background electrolyte solution. Poly(glycidylmethacrylate-co-N-vinylpyrrolidone) coating was applied to the capillary to suppress the electroosmotic flow and to improve the repeatability of the migration times. Electrical field strengths up to 2000 Vcm(-1) were applied in separations and the separation efficiencies were compared with theoretical values calculated on the basis of plate height theory. The contributions to the total plate height were calculated for injection plug length, diffusion, Joule heating, electromigration dispersion, analyte adsorption to the capillary wall, and detector slit aperture length. Analyte diffusion coefficients were measured by Taylor dispersion method, while distribution constants were measured chromatographically. Agreement between the calculated and empirical results was fairly good even though some approximations were required. In most cases the longitudinal diffusion contribution governed the total plate height, while the contribution of Joule heating was insignificant even at exceptionally high field strengths used. The relatively long detection slit aperture was found to influence the separation efficiency strongly, while the other dispersion sources that were investigated were of minor importance, except for adsorption in the case of one analyte. With all analytes, the dispersive effect of longitudinal diffusion was reduced as the field strength was increased, leading to enhanced migration velocities and faster separations.
PubMed ID
12761786 View in PubMed
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Purification and characterization of a novel organic solvent-tolerant and cold-adapted lipase from Psychrobacter sp. ZY124.

https://arctichealth.org/en/permalink/ahliterature294687
Source
Extremophiles. 2018 Mar; 22(2):287-300
Publication Type
Journal Article
Date
Mar-2018
Author
Yue Zhang
Fangling Ji
Jingyun Wang
Zhongji Pu
Bo Jiang
Yongming Bao
Author Affiliation
School of Life Science and Biotechnology, Dalian University of Technology, No. 2 Linggong Road, Ganjingzi District, Dalian, 116024, China.
Source
Extremophiles. 2018 Mar; 22(2):287-300
Date
Mar-2018
Language
English
Publication Type
Journal Article
Keywords
Bacterial Proteins - chemistry - genetics - metabolism
Enzyme Stability
Hexanes - chemistry
Lipase - chemistry - genetics - metabolism
Psychrobacter - enzymology - genetics
Solvents - chemistry
Substrate Specificity
Abstract
By screening 25 different psychrophilic strains isolated from the Arctic habitat, we isolated a strain capable of producing lipase. We identified this strain as Psychrobacter sp. ZY124 based on the amplified 16S rDNA sequence. The lipase, named as Lipase ZC12, produced from the supernatant of Psychrobacter sp. ZY124 cultured at 15 °C was purified to homogeneity by ammonium sulfate precipitation followed by Phenyl Sepharose FF gel hydrophobic chromatography. Based on the obtained amino acid sequence, Lipase ZC12 is classified as a member of the Proteus/psychrophilic subfamily of lipase family I.1; it has a molecular weight of 37.9 kDa. We also determined that the apparent optimum temperature for Lipase ZC12 activity is 40 °C. Lipase ZC12 shows remarkable organic solvent tolerance by remaining more 50% after incubated with 10-90% different organic solvents. In addition, acyl chain esters with C12 or longer were confirmed to be preferable substrates for Lipase ZC12. Lipase ZC12 also shows better stereoselectivity for (R, S)-1-phenylethanol chiral resolution in n-hexane solvent with (S)-1-phenylethanol (eep 92%) and conversion rate (39%) by transesterification reactions. These properties may provide potential applications in biocatalysis and biotransformation in non-aqueous media, such as in detergent, transesterification or esterification and chiral resolution.
PubMed ID
29332142 View in PubMed
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14 records – page 1 of 2.