bluuebunny/crossref_metadata_2025_split huggingface dataset:
Antistatic and wetting properties of chemodegradable cationic surfactants containing 1,3‐dioxolane moiety
Authors: Wilk Kazimiera A. , Poźniak Ryszard , Sokoŀowski Adam 
Published: November 2006

AbstractIn this paper we report some performance properties of [(2‐alkyl‐1,3‐dioxolane‐4‐yl)methyl]trimethylammonium bromides (Cn‐D‐TAB, where Cn=n‐C9H19, n‐C11H23, n‐C13H27), [(2,2‐dialkyl‐1,3‐dioxolane‐4‐yl)methyl] dimethylammonium bromides (CnCm‐D‐TAB, where Cn=n‐C8H17, n‐C10H21 and Cm=CH3 or Cn=Cm=n‐C6H13), in relation to classical alkyltrimethylammonium bromides (Cn‐TAB, where Cn=n‐C12H25, n‐C14H29 or C16H33) and dialkyldimethylammonium bromides (CnCm‐DAB, where Cn=Cm=n‐C10H21 and C12H25). Antistatic properties were measured by means of surface resistance (Rs), half charge decay time τ1/2, and maximal voltage induced (Uind) on polyethylene (PE) film and polypropylene (PP) nonwoven fabric. Wetting ability is reported as the concentration of surfactant necessary for immersion of a cottonfabric ring in 100 s, according to the Polish Standard PN‐74/C‐04800. All acetal‐type surfactants showed the antistatic effect. The best results were given by C9‐D‐TAB [Rs=8.5·107 (PE), 1.1·108 Ω (PP); τ1/2=0.25 (PE), 0.30 s (PP); Uind=205 (PE), 220 V (PP)] and C11‐D‐TAB [Rs=8.7·107 (PE), 1.3·108 Ω (PP); τ1/2=0.25 (PE), 0.30 s (PP); Uind=190 (PE), 340 V (PP)] in relation to pure PE foils and PP fabric: Rs=3.0·1014 (PE), 9.8·1014 Ω (PP); τ1/2=>600 (PE), >600 s (PP); Uind=985 (PE), 940 V (PP). Both C9‐D‐TAB and C11‐D‐TAB indicate similar degrees of antistatic ability compared to C10C10‐DAB. All Cn‐TAB compounds do not show any antistatic effects. It was concluded that addition of the 1,3‐dioxolane moiety to the hydrophobic tail of quaternary ammonium salts promotes both antistatic and wetting properties. Additionally, methyl or n‐hexyl group incorporation at the C‐2 carbon atom in the 1,3‐dioxolane ring significantly decreases the surface conductivity.
Surface activity of mixtures of oxyethylated methyl dodecanoate and sodium dodecylbenzenesulfonate
Authors: Makowska Danuta , Hreczuch Wieslaw , Zimoch Jolanta , Bogacki Mariusz B. , Szymanowski Jan 
Published: November 2006

AbstractSurface and interfacial tension and detergency of mixtures containing oxyethylated methyl dodecanoate and sodium dodecylbenzenesulfonate were determined. Synergism in the surface tension reduction was not observed. The competition for adsorption at the air/water interface between oxyethylated methyl dodecanoate and sodium dodecylbenzenesulfonate depended on the considered surface tension, the weight ratio of surfactants in the aqueous phase, and the hydrophile‐lipophile balance of the nonionic surfactant. Generally, coverage of the interface with oxyethylated methyl dodecanoate increased when surface tension decreased. Nonionics were the dominant species at the interface in the important region of surface activity, i.e., for surface tensions below 40 mN m−1. The mole fraction of the hydrophobic nonionic at the interface was higher than the contribution of hydrophilic oxyethylates. An increase of the surfactant ratio in the bulk phase affects the interfacial ratio of surfactants in the same way. The lowest interfacial tension (1.5 mN m−1) at the hexadecane/water interface was observed for oxyethylated methyl dodecanoate having an average degree of oxyethylation equal to 8 and 10. Nearly 5 min was needed to achieve equilibrium value. Mixtures with sodium dodecylbenzenesulfonate decreased the interfacial tension somewhat less efficiently but the equilibrium was rapidly established. The standard washing powders containing oxyethylated methyl dodecanoates exhibited washing ability similar to that obtained for the powder with traditional alcohol oxyethylate.
Fatty amide ethoxylates: Synthesis and self‐assembly
Authors: Folmer Britta M. , Holmberg Krister , Klingskog Eva Gottberg , Bergström Karin 
Published: November 2006

AbstractA series of fatty acid monoethanolamide ethoxylates was synthesized. Tensiometry and fluorescence were used to study the solution behavior of this surfactant series. The effec of the amide bond, the effect of unsaturations in the hydrocarbon chains, and the effects of the oxyethylene chain length were investigated. The presence of the amide group was found to lead to a decrease in the critical micelle concentration (CMC), an effect that is probably due to the formation of hydrogen bonds between neighboring molecules. The surface tension at the CMC was higher when an amide bond was present in the surfactant. This probably reflects the increase in size of the polar group (decrease in the critical packing parameter value) which is unfavorable for close alignment of surfactant molecules at the air‐water interface. The presence of unsaturations in the hydrophobic tail gave an increase in the CMC. This may partly be due to the surfactants becoming more hydrophilic and partly to the increased bulkiness of the chains, rendering packing into closed aggregates and formation of hydrogen bonds between amide groups more difficult. The cross‐sectional headgroup areas of the surfactants increased with the degree of unsaturation as a consequence of more unfavorable packing at the surface.
Synthesis and characterization of surface‐active compounds derived from cholesterol derivatives and glucose
Authors: Piispanen Peter S. , Byström Styrbjörn , Svensson Martin , Kronberg Bengt , Blute Irena , Norin Torbjörn 
Published: November 2006

AbstractThe synthesis and characterization of surface‐active compounds based on various steroid derivatives and glucose are presented. The hydrophobic and hydrophilic parts of the compounds were linked via glucosidic bonds. All compounds were found to have very low water solubility and only limited solubility in various organic solvents. The compounds were investigated according to their ability to interact with an anionic surfactant, sodium dodecylsulfate (SDS), in order to induce a decrease in the critical micelle concentration (CMC) of the surfactants. This synergistic effect was pronounced for cholestanol‐6‐on‐β‐D‐glucopyranoside and for cholestan‐3,6‐diol‐β‐D‐glucopyranoside. These two compounds lowered the CMC from 8 to 6 and 0.6 mM, respectively, for water solutions of SDS/glucoside with a molar ratio of 92∶8. Furthermore, the ability of the compounds to stabilize lipid membranes, in liposomes, at varying concentrations of Ca2+, was studied. The compounds were, as expected, found to induced stabilization similar to that of cholesterol.
A didodecyldimethylammonium bromide ternary system: Characterization of three‐phase stable emulsions by optical microscopy
Authors: Mele Stefania , Khan Ali , Monduzzi Maura 
Published: November 2006

AbstractA preliminary characterization of the didodecyldimethyl ammonium bromide (DDAB)/water (W)/per fluorooctane (PFO) ternary system at 25°C is presented. The gradual addition of water, followed by mixing, to DDAB/PFO mixtures produces very stable emulsions for water contents greater than 20 wt%. On the basis of macroscopic observation, at least four different types of emulsions form up to a water content of around 97 wt%. On the basis of high conductivity values, a water‐continuous domain is suggested at all compositions. A second phase diagram, considerably different in phase boundaries, is obtained by adding the PFO oil to DDAB/W samples. This allowed us to ascertain the swelling properties of Lα1 and Lα2 lamellar phases. Optical microscopy in the presence and in the absence of polarized light revealed the formation of lamellar liquid crystals either as randomly localized islands or as rings surrounding the oil droplets. Vesicles are identified at high water content. The contemporaneous presence of both Lα1 and Lα2 lamellar phases causes a synergistic effect in the PFO stabilization.
Biosurfactant production by Bacillus coagulans
Authors: Huszcza Ewa , Burczyk Bogdan 
Published: November 2006

AbstractA new biosurfactant producer, Bacillus coagulans, was isolated from soil. Its 24‐h‐old culture broth had a low surface tension (27–29 mN/m). Optimization of cell growth of this bacterium led to maximal biosurfactant production with glucose or starch as the organic carbon source, a pH in the range 4.0–7.5, and incubation temperatures from 20 to 45°C. The crude biosurfactants obtained after neutralization and lyophilization of the acid precipitate yielded a minimal aqueous solution surface tension value of 29 mN/m and an interfacial tension value of 4.5 mN/m against hexadecane. The critical micelle concentration of the crude biosurfactants was 17 mg/L. Addition of NaCl to the aqueous solution of the crude product caused lowering of surface tension at both the aqueous solution‐air and aqueous solution‐n‐hexadecane interfaces. These results indicate that the biosurfactants obtained have potential environmental and industrial applications and may have uses in microbially enhanced oil recovery.
Novel glucose‐derived gemini surfactants with a 1,1′‐ethylenebisurea spacer: Preparation, thermotropic behavior, and biological properties
Authors: Laska Urszula , Wilk A. , Maliszewska Irena , Syper Ludwik 
Published: November 2006

AbstractIn the search for environmentally safe surfactants made from inexpensive and renewable sources, the interest has mainly been focused on new saccharide derivatives. This report describes the synthesis of newly designed nonionic gemini compounds comprising two reduced sugar headgroups, two alkyl tails, and a 1,1′‐ethylenebisurea entity as the spacer linking two amphiphilic glucose‐derived moieties. Thus, the series of N,N′‐bis[(3‐alkyl‐3‐deoxy‐d‐glucitol)ureido]ethylenediamines (bis(CnGT), with Cn=n‐C9H9, n‐C6‐H13, n‐C8H17, n‐C10H21, or n‐C12H25), were prepared using a convenient procedure starting from easily accessible reagents such as d‐glucose, n‐alkylamines, urea, and ethylenediamine. Their structure and purity were confirmed by means of elemental analysis, electrospray ionization mass spectrometry, and 1H and 13C nuclear magnetic resonance spectroscopy. Additionally, the present contribution introduces selected properties of these surfactants, including their thermotropic behavior and biological properties. The presence of two phase transition points, determined using the differential scanning calorimetry method, indicates liquid‐crystalline mesophase formation upon heating. Furthermore, using the closed‐bottle test (OECD Guideline 301D) as well as the biological oxygen demand test for insoluble substances for biodegradability measurements, it has been concluded that the tested glucose‐derived gemini structures achieve more than 60% biodegradation after 64–75 test days. All tested surfactants were practically nontoxic to bacteria, yeast, and molds. Owing to their fitting aggregation ability as well as their nontoxicity, they constitute an interesting group of surfactants for various applications.
Microemulsion phase behavior of anionic‐cationic surfactant mixtures: Effect of tail branching
Authors: Upadhyaya A. , Acosta E. J. , Scamehorn J. F. , Sabatini D. A. 
Published: November 2006

AbstractThis research evaluated middle‐phase microemulsion formation by varying the mole ratio of anionic and cationic surfactants in mixtures with four different oils (trichloroethylene, n‐hexane, limonene, and n‐hexadecane). Mixtures of a double‐tailed anionic surfactant (sodium dihexyl sulfosuccinate, SDHS) and an unbalanced‐tail (i.e., doubletailed with tails of different length) cationic surfactant (benzethonium chloride, BCl) were able to form microemulsions without alcohol addition. The amount of NaCl required to form the middle‐phase microemulsion decreased dramatically as an equimolar anionic‐cationic surfactant mixture was approached. Although the mixture of anionic and cationic surfactants demonstrated a higher critical microemulsion concentration (cμc) compared to the anionic surfactant alone, the Winsor Type IV single‐phase microemulsion started at lower surfactant concentrations for the anionic‐cationic mixture than for the anionic surfactant alone. Under optimum middlephase microemulsion conditions, mixed anionic‐cationic surfactant systems solubilized more oil than the anionic surfactant alone. Pretreatment detergency studies were conducted to test the capacity of these mixed surfactant systems to remove oil form fabrics. It was found that anionic‐rich mixed surfactant formulations yielded the largest oil removal, followed by cationic‐rich systems.
Synergism in the wetting properties of ternary surfactant mixtures
Authors: Hauthal Hermann G. , Jürges Peter , Möhle Lothar , Ohlerich Udo 
Published: November 2006

AbstractIt has been shown that ternary surfactant synergism can be predicted on the basis of nonideality parameters of binary subsystems derived from advancing contact angles. Studies with appropriate surfactant mixtures of glucamides, ether sulfates, secondary alkane sulfonates, and alkylamidopropyl betaines were performed on substrates of different polarity.
The effect of mixed surfactants on enhancing oil recovery
Authors: El‐Batanoney M. , Abdel‐Moghny Th. , Ramzi M. 
Published: November 2006

AbstractMicelles composed of mixed surfactants with different structures (mixed micelles) are of great theoretical and industrial interest. This work pertains tomaximizing interfacial tension (IFT) reduction via surfactant pairs. In this respect, four types of fatty acid amides based on lauric, myristic, palmitic, and stearic acids were blended with dodecyl benzene sulfonic acid at a molar ratio of 4∶1 and designated as A1, A2, A3, and A4, respectively. The IFT was measured for each blend at different concentrations using Badri crude oil. The most potent formula (A4) was evaluated for using in enhanced oil recovery (EOR). The IFT was tested in the presence of different electrolyte concentrations with different crude oils at different temperatures. Finally several runs were devoted to study the displacement of Badri crude oil by A4 surfactant solution using different slug sizes of 10, 20, and 40% of pore volume (PV). The study reveled that Badri crude oil gave ultra‐low IFT at lowest surfactant concentration and 0.5% of NaCl. The recovery factor at a slug size of 20% PV was 83% of original oil in place compared with 59% in case of conventional water flood.
Detergency and foam studies on linear alkylbenzene sulfonate and secondary alkyl sulfonate
Authors: Goon Piyali , Bhirud R. G. , Kumar V. V. 
Published: November 2006

AbstractAmong anionic surfactants used in detergent products, the sodium salt of linear alkylbenzene sulfonate (NaLAS) is the only surfactant belonging to the aromatic class; the others are aliphatic, e.g., the sodium salt of secondary alkyl sulfonate (NaSAS). We observed earlier that certain conformational changes taking place in aromatic anionic surfactants (NaLAS) upon micellization can be brought about in aliphatic anionic surfactants (NaSAS) by addition of phenol. In this paper we examined how conformational changes at the molecular level translated into macroscopic properties such as foam and detergency. We performed foam and detergency measurements on NaLAS, NaSAS, and NaSAS/phenol systems. Foam behavior of these systems is shown to be dependent only upon calcium ion sensitivities of the surfactants whereas the detergency results have a dependence on conformational changes at the molecular level.
A single oral administration of conjugated linoleic acid enhanced energy metabolism in mice
Authors: Ohnuki Koichiro , Haramizu Satoshi , Oki Kasumi , Ishihara Kengo , Fushiki Tohru 
Published: November 2006

AbstractWe investigated the effect of a single oral administration of conjugated linoleic acid (CLA) on energy metabolism in mice. Male Std ddY mice were orally administered CLA (5 mL/kg weight) or linoleic acid (5 mL/kg weight) (both solutions at concentrations of 73.5%) as a control. Oxygen consumption was significantly greater in the CLA‐administered mice than in the control mice. Respiratory quotient was slightly lower in the CLA‐administered mice than in the control mice. We calculated fat and carbohydrate oxidation from oxygen consumption and respiratory quotient. Fat oxidation in the CLA‐administered mice was significantly higher than in the control mice, and there was no difference in carbohydrate oxidation. Serum concentrations of noradrenalin and adrenalin in the CLA administered mice were significantly higher than in the control mice. These results suggested that CLA enhanced sympathetic nervous activity and energy metabolism.
PC and PE synthesis: Mixed micellar analysis of the cholinephosphotransferase and ethanolaminephosphotransferase activities of human choline/ethanolamine phosphotransferase 1 (CEPT1)
Authors: Wright Marcia M. , McMaster Christopher R. 
Published: November 2006

AbstractThe human choline/ethanolamine phosphotransferase 1 (CEPT1) gene codes for a dual‐specificity enzyme that catalyzes the de novo synthesis of the two major phospholipids through the transfer of a phosphobase from CDP‐choline or CDP‐ethanolamine to DAG to form PC and PE. We used an expression system devoid of endogenous cholinephosphotransferase and ethanolaminephosphotransferase activities to assess the diradylglycerol specificity of CEPT1. A mixed micellar assay was used to ensure that the diradylglycerols delivered were not affecting the membrane environment in which CEPT1 resides. The CEPT1 enzyme displayed an apparent Km of 36 μM for CDP‐choline and 4.2 mol% for di‐18∶1 DAG with a Vmax of 14.3 nmol min−1 mg−1. When CDP‐ethanolamine was used as substrate, the apparent Km was 98 μM for CDP‐ethanolamine and 4.3 mol% for di‐18∶1 DAG with a Vmax of 8.2 nmol min−1 mg−1. The preferred diradylglycerol substrates used by CEPT1 with CDP‐choline as the phosphobase donor were di‐18∶1 DAG, di‐16∶1 DAG, and 16∶0/18∶1 DAG. A major difference between previous emulsion‐based assay results and the mixed micelle results was a complete inability to use 16∶0(O)/2∶0 as a substrate for the de novo synthesis of platelet‐activating factor when the mixed micelle assay was used. When CDP‐ethanolamine was used as the phosphobase donor, 16∶0/18∶1 DAG, di‐18∶1 DAG, and di‐16∶1 DAG were the preferred substrates. The mixed micelle assay also allowed the lipid activation of CEPT to be measured, and both the cholinephosphotransferase and ethanolaminephosphotransferase activities displayed the unusual property of product activation at 5 mol%, implying that specific lipid activation binding sites exist on CEPT1. The protein kinase C inhibitor chelerythrine and the human DAG kinase inhibitor R59949 both inhibited CEPT1 activity with IC50 values of 40 μM.
Phospholipid FA of piezophilic bacteria from the deep sea
Authors: Fang Jiasong , Chan Olivia , Kato Chiaki , Sato Takako , Peeples Tonya , Nigggemeyer Karl 
Published: November 2006

AbstractPhospholipid FA (PLFA) profiles were determined on four piezophilic bacteria from the deep sea: Moritella japonica DSK1, Shewanella violacea DSS12, S. benthica DB6705, and S. benthica DB21MT‐2. The total concentrations of PLFA were higher in strains grown at low pressure (DSK1, 10 MPa, 27.0 mg/g dry wt cells; DSS12, 50 MPa, 24.0 mg/g), and lower in strains grown at high pressure (DB6705, 85 MPa, 1.9 mg/g; DB21MT‐2, 100 MPa, 3.0 mg/g). The piezophilic bacteria were characterized by a high abundance of unsaturated FA (62–73% of total FA). In particular, PUFA were detected in all piezophiles examined. Moritella japonica DSK 1 produced 22∶6n−3 (DHA), whereas the three Shewanella strains produced 20∶5n−3 (EPA) with trace amounts of DHA. The detection of low levels of the medium‐chain‐length PUFA 18∶2n−6 and 18∶3 (DSK1) and 20∶2 (DB6705 and DB21MT‐2) suggests that the biosynthesis of EPA and DHA may be regulated by the formation and desaturation of di‐and tri‐unsaturated FA.
Docosahexaenoic acid‐and eicosapentaenoic acid‐enriched cardiolipin in the manila clam Ruditapes philippinarum
Authors: Kraffe Edouard , Soudant Philippe , Marty Yanic , Kervarec Nelly 
Published: November 2006

AbstractThe FA composition of cardiolipin (CL) from the Manila clam Ruditapes philippinarum was investigated in whole body and individual organs. CL was isolated by HPLC and its chemical structure characterized using NMR spectroscopy. Two prominent FA, EPA and DHA, were found in approximately equal proportions, contributing together up to 73 mol% of the total FA. The FA composition of CL is presumed to reflect a specific synthesis pathway independent of diet and of total glycerophospholipid FA composition. To the best of our knowledge, this is the first time that a CL dominated by the two PUFA 22∶6n−3 and 20∶5n−3 has been characterized and described. This EPA+DHA specificity of the CL in the Manila clam is though to reflect a functional and structural modification of mitochondrial membranes of this bivalve species compared with scallops, oysters, and mussels that possess a CL dominated by DHA. The FA composition and levels of CL differed little between separated organs, and the large pool of DHA and EPA was found fairly equally distributed in gills, mantle, foot, siphon, and muscle. However, whereas DHA and PUFA levels were most stable between organs, EPA and arachidonic acid were significantly more variable and seemed to be interrelated.
Modulation of respiratory syncytial virus‐induced prostaglandin E2production by n−3 long‐chain polyunsaturated fatty acids in human respiratory epithelium
Authors: Bryan Dani‐Louise , Hart Prue , Forsyth Kevin , Gibson Robert 
Published: November 2006

AbstractInfection with respiratory syncytial virus (RSV) results in substantial infant morbidity and has been associated with the subsequent development of childhood asthma. Inflammatory mediators produced by both the epithelium and tissue leukocytes during RSV infection stimulate the release of chemotactic factors by the respiratory epithelium and the subsequent influx of inflammatory cells, predominantly neutrophils. We investigated the production of inflammatory mediators [prostaglandin E2(PGE2), interleukin (IL)‐1β, tumor necrosis factor α] and chemokines [IL‐8, RANTES (regulation on activation, normal T cell expressed and secreted)] by alveolar epithelial cells in response to RSV infection. Infection of a human alveolar epithelial transformed cell line (A549 cells) with live RSV substantially increased production of PGE2, IL‐8, and RANTES. By altering cell membrane FA through incorporation of the long‐chain PUFA (LCPUFA) arachidonic acid, EPA, and DHA, we were subsequently able to significantly modulate PGE2production by the infected epithelium. Because of the dynamic nature of the effects of PGE2on lung function, regulation of this prostaglandin during RSV infection by n−3 LCPUFA has the potential to significantly alter the disease process.
New ceramides from Rantherium suaveolens
Authors: Oueslati M. Habib , Mighri Zine , Jannet H. Ben , Abreu Pedro M. 
Published: November 2006

AbstractA mixture of five new ceramides was isolated from the aerial parts of Rantherium suaveolens and characterized by spectroscopic and chemical methods. Their structures were elucidated by spectroscopic and chemical methods as (2S, 3S, 4R, 2′R, 14E)‐2‐(2′‐hydroxydocosanoylamino)‐14‐octadecene‐1,3,4‐triol (1), (2S,3S,4R,2′R, 14F)‐2‐(2′‐hydroxytricosanoylamino)‐14‐octadecene‐1,3,4‐triol (2), (2S,3S,4R,2′R,14F)‐2‐(2′‐hydroxytetracosanoylamino)‐14‐octadecene‐1,3,4‐triol (3), (2S,3S,4R,2′R,14E)‐2‐(2′‐hydroxypentacosanoylamino)‐14‐octadecene‐1,3,4‐triol (4), and (2S,3S,4R,2′R,14E)‐2‐(2′‐hydroxyhexacosanoylamino)‐14‐octadecene‐1,3,4‐triol (5).