bluuebunny/crossref_metadata_2025 huggingface dataset:
α‐Sulfonato palmitic acid methyl ester‐hexaoxyethylene monododecyl ether mixed surfactant system: Interfacial, thermodynamic, and performance property study
Authors: Patil Sandeep R. , Mukaiyama Tsuneharu , Rakshit Animesh Kumar
Published: November 2006

Interfacial, thermodynamic, and performance properties of aqueous binary mixtures of α‐sulfonato palmitic acid methyl ester, C14H29CH(SO3Na)COOCH3(PES), and hexaoxyethylene monododecyl ether, CH3(CH2)11(OCH2CH2)6OH (C12E6), were investigated with tensiometric, conductometric, fluorimetric, and viscometric techniques. The critical micelle concentration (CMC), maximum surface excess, minimum area per molecule of surfactant at the air/water interface, and the thermodynamics of micellization and adsorption were determined. The CMC was very low for mixed systems, indicating probable use as a detergent with less effect on the environment because of surfactant biodegradability and less amount in the environment. The interaction parameter βm, computed by using the theory of Rubingh and Maeda, indicated an attractive interaction (synergism) between the surfactant molecules, which was also confirmed by proton nuclear magnetic resonance studies in the mixed micelle. The micellar aggregation number (Nagg), determined by using a steady‐state fluorescence quenching method at a total surfactant concentration of about ∼10 mM at 25°C, was almost independent of the surfactant mixture composition. The micropolarity and the binding constant (Ksv) for the C12E6/PES mixed system were determined by the ratio of the intensities (I1/I3) of the pyrene fluorescence emission spectrum, and the local microenvironment inside the micelle was found to be polar. The viscosity of the mixed system at all mole fractions suggested that mixed micelles are nonspherical in nature. The cloud point of oxyethylene group‐containing surfactants was increased by the addition of PES. Foaming was temperature dependent, and a 1∶1 mixed system showed minimum foaming. All performance properties were composition dependent.
Optimization of transparent gels for cosmetic compositions
Authors: Comelles F. , Sánchez‐Leal J. , González J. J.
Published: November 2006

The necessary conditions were established by which several biocompatible ingredients (phosphated oleyl ether 3 mol ethylene oxide as surfactant, oleic acid as the lipophilic ingredient, and diethylene glycol monoethyl ether and 1,2‐propanediol as glycols) were combined to formulate transparent gels through dilution with water. This study was carried out at three constant levels of surfactant concentration (5, 10, and 15%), which determined in each case the appropriate ratios between the other three components to give transparent gels. These ratios were expressed as the global ratios between oleic acid and the two glycols together (ranging from 1∶9to 1∶3), whereas the internal ratios between the glycols moved in each case from 1∶0 to 0∶1. The systems with 5% of initial surfactant and a global ratio between oleic acid and the glycols of 1∶7 appeared to be the most effective for minimizing the final surfactant content. They furnished transparent gels at specified levels of water dilution, resulting in final surfactant concentrations in the range of 2–4%. Microscopic observation of the gels through polarized light showed the typical pattern of a lamellar liquid crystal structure. The mild characteristics of these gels, given their low surfactant content and the harmlessness of the other components, in addition to their attractive transparency and the rheological characteristics of plastic fluids make them suitable for application as topical formulations in the cosmetic or pharmaceutical fields.
Influence of glycols on the formation of lamellar liquid crystals with an anionic surfactant, oleic acid, and water
Authors: Comelles F. , Sánchez‐Leal J. , González J. J.
Published: November 2006

The influence of glycol structures on the formation of lamellar liquid crystals with the physical appearance of transparent gels in formulations composed of an anionic surfactant, oleic acid, and water was investigated. The glycols studied belong to alkyl derivatives of ethylene glycol and diethylene glycol. The relationships between the ingredients of the so‐called basic compositions—surfactant, oleic acid, and glycol—were optimized to form transparent gels when diluted with water. The ranges in which transparent gels existed were compared for the systems with different glycols. The most suitable glycols, as defined by the lowest surfactant content in the final transparent gels, were ethylene glycol methyl ether and especially methyl and ethyl derivatives of diethylene glycol. Formulations with 2–3% surfactant could be prepared with these glycols. These data were correlated with the polarity of the glycol structures described by means of log P (octanol/water partition coefficient). Transparent gel formation occurred for log P values ranging from approximately 0.5 to −0.5, whereas liquid crystal formation did not result from higher or lower values.
Soybean oil microemulsions with oleic acid/glycols as cosurfactants
Authors: Comelles F. , Sánchez‐Leal J. , González J. J.
Published: November 2006

The preparation of biocompatible microemulsions of soybean oil in systems made of anionic surfactant, oleic acid, water, and several glycols was considered. The selected glycols were ether derivatives (methyl, ethyl, dimethyl, and diethyl ether) of ethylene glycol and diethylene glycol. The study was performed using pseudoternary phase diagrams in which the three apexes were occupied by soybean oil, a combination of surfactant/oleic acid, and a combination of water/glycol, respectively. The widest regions of microemulsions were obtained for systems containing methyl ether and especially ethyl ether of both ethylene glycol and diethylene glycol. The two latter compounds allowed the preparation of oil‐in‐water, bicontinuous, and water‐in‐oil microemulsions with final surfactant contents of 3–4%.
Lipase‐mediated synthesis of alkyl ricinoleates and 12‐hydroxy stearates and evaluation of the surfactant properties of their sulfated sodium salts
Authors: Karuna M. S. L. , Reddy J. R. C. , Rao B. V. S. K. , Prasad R. B. N.
Published: November 2006

An efficient and simple lipase‐mediated synthesis of alkyl ricinoleates and 12‐hydroxy stearates was performed by transesterification of methyl ricinoleate/12‐hydroxy stearate and various alcohols in a solvent‐free system without estolide formation. The reaction conditions were optimized by varying the temperature, pressure, and dosage of lipase. Sulfates of alkyl ricinoleates/12‐hydroxy stearates were evaluated for surfactant properties such as surface tension, critical micelle concentration, emulsifying properties, foaming power, and calcium tolerance. The surfactant properties of sulfated alkyl ricinoleates were found to be superior to the sulfated alkyl 12‐hydroxy series. The surfactant properties of the above two series of compounds were then compared with sodium dodecyl sulfate, and the properties of sulfated dodecyl ricinoleate and sulfated dodecyl 12‐hydroxy stearate were found to be comparable with sodium dodecyl sulfate.
Quaternary methyl carbonates: Novel agents for fabric conditioning
Authors: Earl Gary W. , Weisshaar Duane E. , Paulson Drew , Hanson Michael , Uilk Janelle , Wineinger Dianna , Moeckly Steven
Published: November 2006

Preparation of quaternary ammonium compounds from various tertiary amines and the (environmentally friendly) alkylating agent dimethyl carbonate (DMC) under conditions within the bounds of industrial production has been carried out. After unsuccessful attempts to catalyze and entrain the process, the reaction has been accelerated by using a 10‐fold excess of alkylating agent. The recovered DMC and solvent have been recycled in up to five subsequent batches without loss of rate or yield. The expected steric hindrance effects on the rate were evidenced by comparison of the half‐lives of dihydrogenatedtallowmethylamine (1 h), tributylamine (4 h), and the ester quat (7.5h). The product methyl carbonate quaternaries have been shown to be noncorrosive to 316 stainless steel for extended periods at elevated temperatures.
Interaction between bisphenol A and micelles of ionic surfactants
Authors: Kosaka Osamu , Sehgal Pankaj , Doe Hidekazu
Published: November 2006

Interactions between bisphenol A (BPA) and ionic surfactants—cationic hexadecyltrimethylammonium bromide (HTAB) and anionic sodium dodecylsulfate (SDS)—were studied by measuring interfacial tensions and the intensities of pyrene fluorescence. The critical micellar concentrations (CMC) decreased with an increase in the BPA concentration, and the degree of that decrease was greater in HTAB than in SDS. In those micelles, BPA interacted more strongly with HTAB than with SDS. Conversely, BPA adsorbed on the air‐water interface cooperatively with the surfactants, even though almost no adsorption of BPA itself was observed. This cooperative adsorption was more enhanced with HTAB than with SDS. Thus, BPA worked on the surfactants to stabilize the micelles and interfacial adsorption. The stability gained by the addition of BPA was greater on the interface than in the micelle. This was evidence of decreased hydrophilicity of the head group of the ionic surfactant, which interacted with BPA, because this decrease acted on the surface activities of the surfactants more directly than on the micelle stabilities. Pyrene fluorescence measurements yielded identical results for the effect on micelle stabilities. It is noteworthy that the fluorescence intensity of peak 1, l1, decreased with an increase in BPA concentrations at constant concentrations of surfactant greater than the CMC, but the peak ratio, l1/l3, remained almost unchanged. This fact was also related to the interaction of BPA with the hydrophilic head groups in the surfactant micelle.
Surfactant studies of quaternary ammonium compounds: Critical surfactant concentration
Authors: Barney Rocky , Carroll Joseph , Delaet Dru
Published: November 2006

Quaternary ammonium salts (otherwise known as “quats”) commonly form the foundation of formulations in the antimicrobial industry. Although many studies have been conducted on the surfactant and biological aspects of single‐component systems, there are few studies concerning the surfactant or biological efficacy of these compounds in multiple‐component formulations. Preliminary data using simple emulsion studies with decane were determined to be inadequate. Several inexpensive ways to determine critical surfactant concentrations were developed with limited resources.
Gemini surfactants
Authors: Rosen Milton J. , Tracy David J.
Published: November 2006

The literature, including patents, describing the emerging area of gemini surfactants is reviewed. The differences in structure/property relationships between gemini and comparable conventional surfactants are described and discussed in terms of their predicted performance properties. Supportive performance data are enumerated.
Surface and thermodynamic parameters of mixed N‐dodecyl N‐trimethylsilane ammonium chloride with isooctyl phenol ethoxylate
Authors: Gad E. A. M. , Omar A. M. A. , Zaki M.
Published: November 2006

Isooctyl phenol ethoxylate was mixed with N‐dodecyl‐N‐trimethylsilane ammonium chloride and N‐hexadecyl‐N‐trimethylsilane ammonium chloride, respectively. The surface tensions of aqueous solutions of cationic‐nonionic mixtures were measured as a function of nonionic concentration at 35°C with constant cationic concentration. By using the Hutchinson method, the surface excess concentrations, surface mole fractions, and interaction parameters of binary surfactant mixtures were calculated. A synergistic effect for reducing surface tension was observed for adsorption at the surface at low concentrations of N‐dodecyl‐N‐trimethylsilane ammonium chloride.
Enhanced propoxylation of alcohols and alcohol ethoxylates
Authors: Cox Michael F. , Weerasooriya Upali
Published: November 2006

An alkoxylation catalyst consisting of a calcium/aluminum complex partially neutralized in an alcohol ethoxylate base was found to be substantially more active than a conventional potassium hydroxide catalyst in the propoxylation of alcohols and alcohol ethoxylates. With the Ca/Al alkoxide catalyst, propoxylation was faster, required less catalyst, and proceeded at lower temperatures. The latter is desirable since it could help reduce the formation of allyl alcohol and allyl alcohol propoxylate by‐products. The two catalysts produced different oligomer distributions, particularly at higher temperatures, which were found to have a marginal impact on surface chemistry.
Nonsolvent quantitation of anionic surfactants and other inorganic ingredients in laundry detergent products by X‐ray fluorescence spectrometry
Authors: Kawauchi Akihiko
Published: November 2006

This paper reports the development of a method for measuring alkyl‐benzene sulfonates, alkyl sulfates, and other inorganic ingredients in laundry detergent products without requiring the use of chlorinated organic solvents such as chloroform. Zeolite is first filtered as a residue on filter paper from an aqueous detergent solution. A calcium solution is then added to the filtrate. Alkyl‐benzene sulfonates, alkyl sulfates, and phosphate are precipitated as calcium salts and recovered as residues via filtration. The filters are then subjected to X‐ray fluorescence spectrometry (XRF) for measuring the levels of zeolite, phosphate, and total anionic surfactant. The remaining filtrate is also subjected to XRF by using the microdroplet preparation for measuring levels of sulfate and silicate. Separately, the level of alkyl‐benzene sulfonates is measured following the same XRF procedure after alkyl sulfates are hydrolyzed using an autoclave. This sample preparation procedure was investigated using XRF and was confirmed to be applicable for simultaneous measurements of alkyl‐benzene sulfonates, alkyl sulfates, zeolite, phosphate, silicate, and sulfate without using any organic solvents. In the method described in this paper, interelement effects between anionic surfactants and phosphate are not negligible. Fluorescent X‐rays of sulfur or phosphorus are absorbed by calcium complexes of phosphate or anionic surfactants. The slope of calibration curves varies with the levels of coexistent elements; external calibration methods cannot be employed for unknown sample matrices. However, for quality assurance purposes, this method is ideal in terms of turnaround time and laboratory hygiene.
Migration behavior of aromatic amines on alumina thin layers developed with water‐in‐oil microemulsion
Authors: Mohammad Ali , Iraqi Eram
Published: November 2006

Water‐in‐oil (w/o) microemulsions consisting of surfactant [sodium dodecyl sulfate (SDS) or N‐Cetyl‐N,N,N‐trimethyl ammonium bromide], water, heptane or hexane, and a cosurfactant (1‐pentanol or butanol) have been used as a mobile phase in combination with alumina, microcrystalline cellulose, silica gel G, silica gel H, and Kieselguhr thin layers to study the retention efficiency of amines. The separation of amines from their ternary and binary mixtures is achieved. Thin layers of alumina as the stationary phase and SDS/water/heptane/1‐pentanol microemulsion as mobile phase is identified as the best chromatographic system for amine analysis. The limits of identification and dilution are reported for amines. Effects of heavy metals, anions, and phenols on the separation efficacy of diphenylamine‐p‐chloroaniline‐p‐nitroaniline have also been examined. The effect of electrolyte in the microemulsion on amine mobility is investigated. The o‐ and p‐isomers move faster compared to the m‐isomer of aniline.
Radiotracer detergency testing in a horizontal‐axis washing machine
Authors: Passwater Deborah K. , Raney Kirk H.
Published: November 2006

Proposed regulations by the U.S. Department of Energy have spurred development of energy‐efficient washing machines that utilize less water and operate with lower energy requirements than conventional machines. As a result, major changes in washing machine design are required. Among expected changes are increased use of a horizontal‐axis wash tub, an increase in fabric‐to‐wash liquor ratio, greater surfactant concentration in the wash water, and reduced average washing temperatures. As a result, surfactants used in future detergent formulations will be required to clean effectively in this new regime while producing minimal foam. Detergency test methods utilizing radiotracer techniques have been developed to study the detergency process in energy‐efficient washing machines. Detergency and redeposition of radiolabeled oily soils can be determined in a full‐size horizontal‐axis washing machine through scintillation counting of wash and rinse water samples. Measurements can be made after each wash process step and combined to determine total cycle detergency. This is a distinct advantage over conventional reflectance detergency methods where only total detergency at the end of the entire washing and rinsing process can be conveniently measured. Also, in contrast to indirect reflectance methods, measurements of absolute soil removal are obtained with the radiotracer method. In this study, soil redeposition was determined by measuring residual radioactivity on fabric swatches and then performing a material balance on the oily soil.
Clearning performance and foaming properties of lauroylamidopropylbetaine/nonionics mixed systems
Authors: Tamura Takamitsu , Iihara Tadashi , Nishida Shigeo , Ohta Seiich
Published: November 2006

Lauroylamidopropylbetaine (LPB) has good cleaning and foaming performance with excellent low skin irritation. We have investigated the relationship between cleaning performance and foaming properties of aqueous solutions containing binary and ternary LPB/nonionic surfactant systems. Foaming properties were evaluated by observing dynamic surface tension and aqueous core thickness of a vertical foam film measured by Fourier transform infrared spectroscopy. The LPB/lauroyldiethanolamide (LDE) system has a positive synergistic effect on cleaning performance and foam stability, estimated from the grease removal test and dishwashing test for a light‐duty detergent. However, this system shows very poor initial foam performance in both the sponge test and Ross‐Miles foam test. This disadvantage of the LPB/LDE system was improved using C12En (polyoxyethylene dodecyl ethers). Addition of C12En promoted dynamic surface tension lowering, indicating an improvement in the initial foaming performance, while maintaining cleaning performance and foam durability. Thus, the LPB/LDE/C12En ternary system has an excellent cleaning and foam performance as a light‐duty liquid detergent.
Proton Nuclear magnetic resonance studies on the aggregation‐induced conformational changes in secondary alkyl sulfate/sulfonate+phenol system
Authors: Kumar V. V. , Goon Piyali , Das S.
Published: November 2006

Many interesting aggregation‐induced conformational changes in sodium salts of linear alkylbenzene sulfonates (NaLAS) previously have been reported. Some of these findings include the looping back of one of the hydrocarbon chains toward the palisade layer and the upfield shift of the meta protons of the phenyl ring upon micellization. The objective of this work is to compare the aggregation behavior of sodium salts of secondary alkyl sulfates (NaSAS) and secondary alkane sulfonates (NaSAlkS) in the presence of added phenol with that of NaLAS. The aggregation behavior of commercial NaSAlkS and several pure NaSAS has been studied in the absence and presence of phenol by 1H nuclear magnetic resonance (NMR) spectroscopy. In the absence of phenol, the protons belonging to the two terminal methyl groups on the two hydrocarbon chains give rise to one triplet above and below the critical micelle concentration (CMC), indicating a similar chemical environment. However, separation of the 1H NMR signals of the terminal methyl groups corresponding to the two hydrocarbon chains is noticed when phenol is added to the NaSAS or NaSAlkS micellar solution. These results indicate that phenol inserts itself into the micelle palisade layer and exerts a phenyl ring effect on the sydrocarbon chains. Because the terminal methyl group of the shorter chain is closer to the phenyl ring, it experiences more ring current effect and hence a separation of the two signals. Corresponding chemical‐shift changes in the proton resonances of phenol are also observed when it is incorporated into the micelle. The ortho protons of phenol remain essentially unshifted while meta and para protons shift upfied. The results indicate that ortho protons of phenol experience an aqueous environment while meta and para protons experience a nonpolar environment confirming the insertion of phenol into the surfactant micelles. Based on these studies, it is concluded that NaSAS/phenol and NaSAlkS/phenol systems mimic the NaLAS system in terms of conformational changes. These results also highlight the fact that the presence of a phenyl ring not only within the molecule (as in the case of NaLAS) but also outside the molecule (added phenol) can be effective in exerting phenyl‐ring effects.
Effect of the lupin protein/surfactant ratio on linear viscoelastic properties of oil‐in‐water emulsions
Authors: Raymundo A. , Franco J. M. , Partal P. , Sousa I. , Gallegos C.
Published: November 2006

This work studies the influence of a low‐molecular‐weight emulsifier/lupin protein ratio on the linear viscoelastic properties of oil‐in‐water emulsions. With this aim, dynamic viscoelasticity tests, as well as droplet‐size distribution measurements, were done. Four types of low‐molecular‐weight emulsifiers were used. From the results, we conclude that emulsions stabilized by emulsifier blends show, in general, lower values of both the linear viscoelasticity functions and Sauter diameter than those found when lupin protein was used as the only emulsifier. Protein‐free emulsions may have similar parameter values when the surfactant induces a structured gel‐like continuous phase. Evolution of the linear viscoelastic functions with the composition of the mixed emulsifier has been explained on the basis of changes in interdroplet interactions, rheological behavior of the continuous phase, and surface viscoelasticity of the adsorbed emulsifier layer. However, the above‐mentioned behavior cannot be explained from changes in the emulsion droplet‐size distribution.
Effects of dietary defatted squid on cholesterol metabolism and hepatic lipogenesis in rats
Authors: Tanaka Kazunari , Ikeda Ikuo , Yoshida Hiroko , Imaizumi Katsumi
Published: November 2006

Male Sprague‐Dawley rats were fed a cholesterol‐free (Exp. 1) or cholesterol‐supplemented (Exp. 2) diet containing 20% casein (control group) or 15% defatted squid and 5% casein (defatted squid group), as protein, for 14 d. Serum and hepatic cholesterol concentrations were lower in rats fed defatted squid than in those fed casein in both cholesterol‐free (−20%, P<0.05 and −15%, P<0.05, respectively) and cholesterol‐supplemented (−25%, P<0.05 and −15%, P<0.05, respectively) diets. Hepatic triglyceride concentration was lower in the defatted squid than in the control groups in both cholesterol‐free (−51%, P<0.05) and cholesterol‐supplemented diets (−38%, P<0.01). The activities of cytosolic fatty acid synthase and the NADPH‐generating enzymes, malic enzyme and glucose‐6‐phosphate dehydrogenase, in the liver were lower in the defatted squid than in the control groups in both cholesterol‐free (−21%, P<0.01, −33%, P<0.05, and −33%, P<0.01, respectively) and cholesterol‐supplemented diets (−34%, P<0.05, −57%, P<0.05, and −67%, P<0.05, respectively). The activity of mitochondrial carnitine palmitoyltransferase in the liver was comparable between the control and defatted squid groups. The activity of Mg2+‐dependent phosphatidate phosphohydrolase in the liver cytosol was lower in the defatted squid (−9%, P<0.05) than in the control groups only in the cholesterol‐free diet. Fecal excretion of total steroids was stimulated by the feeding of defatted squid in both cholesterol‐free (+77%, P<0.005) and cholesterol‐supplemented diets (+29%, P<0.01). These results suggest that the nonlipid fraction of squid exerts a hypocholesterolemic effect by increasing the excretion of total steroids in feces. The fraction also induces a triglyceride‐lowering activity in the liver by decreasing hepatic lipogenesis.
Synthetic routes and lipase‐inhibiting activity of long‐chain α‐keto amides
Authors: Chiou Antonia , Verger Robert , Kokotos George
Published: November 2006

Synthetic routes to primary and N‐alkyl α‐keto amides are presented in this paper. Primary α‐keto amides may be prepared by using an aldehyde as starting material. Commercially available α‐keto acids may be coupled in high yield with primary amines by the mixed carbonic anhydride method affording N‐alkyl α‐keto amides. Alternatively, N‐alkyl α‐keto amides may be prepared by coupling long‐chain α‐hydroxy acids with amino components, followed by oxidation with pyridinium dichromate or NaOCl in the presence of 4‐acetamido‐2,2,6,6‐tetramethyl‐1‐piperidinyloxy free radical. The α‐keto amide derivatives prepared according to these procedures were tested for their ability to form stable monomolecular films at the air/water interface. The inhibition of porcine pancreatic lipase by the α‐keto amides, spread as mixed films with 1,2‐dicaprin, was studied with the monolayet technique. Among the compounds tested in this study, methyl 2‐[(2‐ketododecanoyl)aminol]hexadecanoate was shown to be the most potent inhibitor, causing a 50% decrease in lipase activity at a 0.09 molar fraction.
Effects of Δ5 polyunsaturated fatty acids of maritime pine (Pinus pinaster) seed oil on the fatty acid profile of the developing brain of rats
Authors: Pasquier E. , Ratnayake W. M. N. , Wolff R. L.
Published: November 2006

Conifer (pine) seeds are a potential source of dietary oils, but their safety and nutritional properties are not well established. Conifer seed oils differ from common edible vegetable oils in having a series of unusual polyunsaturated fatty acids (PUFA) with a polymethylene‐interrupted (PMI) double bond system and a double bond at the Δ5 position. A rat study was conducted to assess whether Δ5 PMI‐PUFA of conifer seeds could alter the levels of n−6 and n−3 long‐chain polyunsaturated fatty acids (LC‐PUFA) in mothers' milk and the developing brain of fetuses and pups. Feeding maritime pine (Pinus pinaster) seed oil (MPO) diet with a Δ5 PMI‐PUFA content of 1.4 g/100 g throughout pregnancy and lactation resulted in a large incorporation of Δ5 PMI‐PUFA in mothers' milk (5.1±0.5% of total fatty acids). The fetus (17 d old) and pup (22 d) brains, however, accumulated very little (0.6 and 0.4% of total fatty acids, respectively) Δ5 PMI‐PUFA. Mother's milk and pup's brain of the MPO group contained normal levels of 20∶4n−6, 22∶4n−6, and 20∶5n−3 compared to a reference group of rats fed a fat blend of sunflower, high‐oleic sunflower, and canola oils. The level of 22∶6n−3, however, was slightly but significantly (P<0.05) higher in milk and pup brain of the MPO group. These results show that Δ5 PMI‐PUFA of MPO exert no negative effect on the levels of n−6 and n−3 LC‐PUFA in rat brain during its early development.
Action of 1‐(11‐selenadodecyl)‐glycerol and 1‐(11‐selenadodecyl)‐3‐trolox‐glycerol against lipid peroxidation
Authors: Raneva Violeta , Shimasaki Hiroyuki , Furukawa Yumi , Ueta Nobuo , Yanishlieva Nedyalka , Aaseng Jon Erik , Partali Vassilia , Sliwka Hans‐Richard , Yoshida Yasukazu , Niki Etsuo
Published: November 2006

The antioxidant action on lipid peroxidation of the synthesized selenium compounds 1‐(11‐selenadodecyl)‐glycerol (SeG) and 1‐(11‐selenadodecyl)‐3‐Trolox‐glycerol (SeIrG, where Trolox=6‐hydroxyl‐2,5,7,8‐tetramethylchroman‐2‐carboxylic acid) was investigated. We compared the reactivity of the selenium compounds toward peroxyl radicals and their inhibitory effect on lipid peroxidation, induced by several kinds of initiating species such as azo compounds, metal ions, and superoxide/nitric oxide in solution, micelles, membranes, and rat plasma. SeTrG, but not SeG, scavenged peroxyl radicals. SeG reduced methyl linoleate hydroperoxides in organic solution and in methyl linoleate micelles oxidized by ferrous ion (Fe2+)/ascorbic acid. In rat plasma SeG and SeTrG decreased the formation of lipid hydroperoxides generated by hydrophilic azo compounds. SeG and SeTrG spared α‐tocopherol (α‐TOH) consumption in multilamellar vesicle membranes oxidized by hydrophilic or lipophilic initiators, and only SeTrG spared α‐TOH in superoxide/nitric oxide oxidized membranes. In rat plasma oxidized by radical initiators (either hydrophilic or lipophilic) or superoxide/nitric oxide, SeTrG suppressed α‐TOH consumption, but SeG had no effect. The two selenium‐containing compounds showed inhibitory effects on lipid peroxidation that depended on their structure, the medium where they acted, and the oxidant used.
Comparison of ex vivo inhibitory effect between 2‐hydroxyestradiol and its 17‐sulfate on rat hepatic microsomal lipid peroxidation
Authors: Takanashi Kaori , Osanai Yasunori , Kyo Takahiro , Yoshizawa Itsuo
Published: November 2006

Two endogenous antioxidants that are speculated to be defense substances against preeclampsia, 2‐hydroxyestradiol (2‐OH‐E2) and its 17‐sulfate, 2‐hydroxyestradiol 17‐sulfate (2‐OH‐E2‐17‐S), were administered to rats to compare their inhibitory effects on hepatic microsomal lipid peroxidation, and the lipid peroxides were determined in NADPH‐ and ascorbic acid‐dependent systems. The two catechols showed a strong inhibitory effect on lipid peroxidation in both systems, and the effect was dose dependent. However, a large difference was observed in their inhibition patterns. After administration of 2‐OH‐E2, the effect appeared immediately and decreased gradually with time. In contrast, the effect of 2‐OH‐E2‐17‐S appeared some time after administration and persisted for a longer time. Both catechols also showed a striking difference in their dynamics. After administration, 2‐OH‐E2 was detected in the blood together with its metabolites, 2‐methoxyestradiol and 2‐methoxyestrone, and they disappeared immediately. In contrast, 2‐OH‐E2‐17‐S was present in the blood for a longer time together with its O‐methylated product, 2‐methoxyestradiol 17‐sulfate, but disappeared from liver microsomes within 2 h after administration. The results imply no occurrence of a direct inhibition effect of 2‐OH‐E2‐17‐S.
Cyanolipid‐rich seed oils from Allophylus natalensis and A. dregeanus
Authors: Avato P. , Rosito I. , Papadia P. , Fanizzi F. P.
Published: November 2006

As a continuation of our study on plants of the Sapindaceae, the chemical composition of the oil extracted from seeds of Allophylus natalensis (Sonder) De Winter and of A. dregeanus (Sonder) De Winter has been investigated. The oil from both species contained approximately equal amounts of TAG and type I cyanolipids (CL), 1‐cyano‐2‐hydroxymethylprop‐2‐en‐1‐oldiesters, with minor amounts of type III CL, 1‐cyano‐2‐hydroxymethylprop‐1‐en‐3‐ol‐diesters. Structural investigation of the oil components was accomplished by chemical, chromatographic (TLC, CC, GC, and GC‐MS), and spectroscopic (IR, NMR) means. GC and GC‐MS analysis showed that C20 FA were dominant in the CL components of the oil from the two species (44–80% vs. 21–26% in TAG), with cis‐11‐eicosenoic acid (36–46%) and cis 13‐eicosenoic acid (paullinic acid, 23–37%) as the major esterified fatty acyl chains in A. natalensis and A. dregeanus, respectively. cis‐Vaccenic acid was particularly abundant (11–31%) in the CL from A. dregeanus, whereas eicosanoic acid (10–22%) was also a major component of CL in both species.
Lipid class distribution of fatty acids including conjugated linoleic acids in healthy and cancerous parts of human kidneys
Authors: Hoffmann Kristina , Blaudszun Jörg , Brunken Claus , Höpker Wilhelm‐Wolfgang , Tauber Roland , Steinhart Hans
Published: November 2006

In this study the FA compositions of healthy and cancerous human renal tissues from the same patients are compared with special reference to the CLA and PUFA content. CLA was preferentially incorporated into neutral lipid compared with phospholipid classes. Its distribution profile was similar to that of monounsaturated FA, but unlike that found with 18∶2n−6. Different incorporation patterns were found for individual CLA isomers. Comparing renal cell carcinoma (RCC) and healthy kidney, the total CLA content was significantly lower in the cholesterylester fraction and significantly higher in the PE and PS fractions from RCC. The most significant differences between healthy and cancerous renal tissue were in the content of t10,c12‐CLA. Furthermore, the lipid class distributions of n−6 PUFA were determined, and several significant differences between RCC and healthy renal tissue were found. This is of interest, as it has been proposed that the anticarcinogenic properties of dietary CLA are associated with their interference in the metabolism of 20∶4n−6. The involvement of CLA in preventing renal cancer cannot be definitively demonstrated from the design of this study, nor was it intended, but the complete determination of the FA composition of adjacent healthy and cancerous tissues may provide an insight if lipids are involved in this disease.
Biochemical, functional, and histochemical effects of essential fatty acid deficiency in rat kidney
Authors: Soares Anísio Francisco , Santiago Rosa Cristina , Martins Aléssio Maria Luíza , Descomps Bernard , de Castro‐Chaves Carmen
Published: November 2006

The present study was designed to examine the effects of EFA deficiency (EFAD) on biochemical, functional, and structural aspects of the kidney in growing and adult rats fed a normal or EFAD diet for 9 wk after weaning. Food and fluid intake (FI), urine volume, and Na+ and K+ excretions were measured weekly from weeks 4 to 8 by placing the rats in individual metabolic cages for 24 h. At week 9, Li+ and a 5% water load, respectively, were administered at 14 and 1.5 h prior to glomerular and proximal tubular function studies, as assessed by 3‐h creatinine (CCr) and Li+ (CLi+) clearances. Hematocrit and urine volume; serum and urine [Cr], [Li+], [Na+], and [K+]; and renal FA distribution were also measured. Data [corrected to 100 g/body weight (bw) and presented as means ±SEM] were significant, at P<‐0.05. Despite a similar ingestion of solids from weeks 4 to 7 (weeks 7 to 10 of life), the rats on the EFAD diet showed a decreased body weight from week 5. From weeks 4 to 8, Fl and urine volume were similar for both groups, but the Fl increased at week 6 in the EFAD group; 24‐h Na+ and K+ excretions were similar at all weeks, except for an increase in the EFAD group for both ions at week 7. In the EFAD group, CCr and CLi+ decreased by 27 and 56.3%, respectively (385.7±33.4 vs. 280±21.1, and 21.0±2.1 vs. 9.2±1.1 μL/min/100 g; n=9 vs. 10), the latter result suggesting increased proximal reabsorption. The 3‐h Na+ and K+ excretions were similar, but the Li+ decreased (0.78±0.06×10−2 vs. 0.32±0.03×10−2 μeq/min/100 g) in the EFAD group, giving additional support to the suggestion. Renal structure was normal and similar for both groups, but the EFAD group showed a more prominent proximal tubule brush border, together with heavier periodic acid‐Schiff staining in all specimens from weeks 5 to 9. In the EFAD group, FA of the n−9 and n−7 series were higher, but most of the n−6 series were lower as a percentage of total lipids in the medulla and cortex. Medullary levels of 20∶4n−6 were maintained, 22∶4n−6 declined twice, arachidonic acid was maintained, and 20∶5n−3 was lower. The EFAD diet affected glomerular function, proximal tubular structure and function, and FA distribution in the rat kidney.
Molecular species of PC and PE formed during castor oil biosynthesis
Authors: Lin Jiann‐Tsyh , Chen Jennifer M. , Chen Pei , Liao Lucy P. , McKeon Thomas A.
Published: November 2006

As part of a program to elucidate castor oil biosynthesis, we have identified 36 molecular species of PC and 35 molecular species of PE isolated from castor microsomes after incubations with [14C]‐labeled FA. The six [14C]FA studied were ricinoleate, stearate, oleate, linoleate, linolenate, and palmitate, which were the only FA identified in castor microsomal incubations. The incorporation of each of the six FA into PC was better than that into PE. The [14C]FA were incorporated almost exclusively into the sn‐2 position of both PC and PE. The incorporation of [14C]stearate and [14C]palmitate into 2‐acyl‐PC was slower compared to the other four [14C]FA. The incorporation does not show any selectivity for the various lysoPC molecular species. The level of incorporation of [14C]FA in PC was in the order of: oleate>linolenate>palmitate>linoleate >stearate>ricinoleate, and in PE: linoleate>linolenate> oleate>palmitate>stearate>ricinoleate. In general, at the sn‐1 position of both PC and PE, linoleate was the most abundant FA, palmitate was the next, and oleate, linolenate, stearate, and ricinoleate were minor FA. The activities of oleoyl‐12‐hydroxylase, oleoyl‐12‐desaturase seem unaffected by the FA at the sn‐1 position of 2‐oleoyl‐PC. The FA in the sn‐1 position of PC does not significantly affect the activity of phospholipase A2, whereas ricinoleate is preferentially removed from the sn‐2 position of PC. The results show that (i) [14C]oleate is most actively incorporated to form 2‐oleoyl‐PC, the immediate substrate of oleoyl‐12‐hydroxylase; (ii) 2‐ricinoleoyl‐PC is formed mostly by the hydroxylation of 2‐oleoyl‐PC, not from the incorporation of ricinoleate into 2‐ricinoleoyl‐PC; and (iii) 2‐oleoyl‐PF is less actively formed than 2‐oleoyl‐PC.
Synthesis and in vitro cytotoxic activity of N‐, F‐, and S‐ether derivatives of podophyllotoxin fatty acid adducts
Authors: Mustafa Jamal , Khan Shabana I. , Ma Guoyi , Walker Larry A. , Khan Ikhlas A.
Published: November 2006

This paper represents the first synthesis, spectroscopic characterization, and antitumor evaluation of F‐, N‐, and S‐containing C4α‐FA derivatives of podophyllotoxin. In a synthetic strategy, a FA unit of 4‐O‐podophyllotoxinyl 12‐hydroxyoctadec‐Z‐9‐enoate 2, a derivative of podophyllotoxin, was functionalized at the C−12 position by incorporating the F atom and N‐containing moieties. The FA olefin (Z, C−9/C−10) of 2 was hydrogenated to produce a derivative possessing a hydroxy function (C−12) on a saturated C18 FA chain. In another synthetic strategy, two S‐ethers of podophyllotoxin (C4α) were synthesized from a terminal unsaturated FA analog, 4‐O‐podophyllotoxinyl undec‐10‐enoate. Syntheses were achieved through effective synthetic procedures; 1H NMR, 13C NMR, IR, and high‐resolution mass data proved excellent tools to characterize these derivatives. In vitro antitumor activity was investigated against a panel of five human neoplastic cell lines, SK‐MEL (malignant, melanoma), KB (epidermal carcinoma, oral), BT‐549 (ductal carcinoma, breast), SK‐OV‐3 (ovary carcinoma), and HL‐60 (human leukemia). Keeping in view the severe lack of tumor selectivity of podophyllotoxin over normal cells, we assayed new analogs against noncancerous mammalian VERO (African green monkey kidney fibroblast) cell lines to gauge their extent of toxicity. Several of these compounds showed excellent moderation of antitumor activity. In general, we found excellent growth inhibition against the human leukemia cell line (HL‐60), particularly for the analogs containing S‐ethers and carbamates. None of the compounds were toxic to normal cell lines.
Inhibition of 2,2′‐azobis(2,4‐dimethylvaleronitrile)‐induced lipid peroxidation by sesaminols
Authors: Kang Myung‐Hwa , Katsuzaki Hirotaka , Osawa Toshihiko
Published: November 2006

We found that sesaminols, a mixture of sesaminol and its stereoisomers, are potent inhibitors of the oxidation of low‐density lipoprotein induced by 2,2′‐azobis(2,4‐dimethylvaleronitrile). Although sesaminols strongly inhibit lipid peroxidation related to their ability to scavenge free radicals, their antioxidant effects have not been investigated. To confirm the involvement of the phenolic moiety in the sesaminol structure in antioxidant activity, sesaminols were reacted with 2,2′‐azobis(2,4‐dimethylvaleronitrile). The reaction products were isolated by high‐performance liquid chromatography and found to have a 1‐cyano‐1,3‐dimethyl‐butyl‐peroxyl group in their structures. These chemical structures suggest that the sesaminols reacted with the alkylperoxyl radicals to form four major reaction products that are stereoisomers of each other, although the stereochemistry of each isomer has not yet been confirmed. Further instrumental analyses of the reaction products may increase our understanding of the antioxidant activity of sesaminols.
Descending serotonergic facilitation of spinal ERK activation and pain behavior
Authors: Svensson Camilla I. , Tran Thao K. , Fitzsimmons Bethany , Yaksh Tony L. , Hua Xiao-Ying
Published: November 2006

Serotonin (5‐HT) derived from bulbo‐spinal projection is released by nociceptive input into the spinal dorsal horn. Here we report that formalin injection in the paw produced pain behavior (flinching) and phosphorylation of spinal ERK1/2 (P‐ERK1/2, indicating activation) in rats. Depletion of spinal 5‐HT by intrathecal (IT) 5,7‐DHT, a serotonergic neurotoxin, profoundly reduced formalin evoked flinching and the increase in P‐ERK1/2. Ondansetron (a 5‐HT3 receptor antagonist) at IT doses that inhibited flinching also attenuated spinal ERK activation. These findings reveal that primary afferent‐evoked activation of spinal ERK requires the input from an excitatory 5‐HT descending pathway.
Manufacturing strategy: The story of its evolution
Authors: Skinner Wickham
Published: November 2006

This essay has two stories to tell: first, as promised, the evolution of what is known as “manufacturing strategy” and, also, the parallel story of the value of combining teaching and research through the Harvard Business School's focus on teaching by the case method. This second tale may be of particular interest in view of recent critiques of business schools and their research practices [Bennis, W.G., O’Toole, J., 2005. How business schools lost their way. Harvard Business Review 83 (5), 96–104].
Collaborative computer-mediated music composition in cyberspace
Authors: Seddon Frederick A.
Published: November 2006

This article reports on an exploratory investigation of the relationship between prior experience of formal instrumental music tuition (FIMT) and the process of collaborative computer-based music composition. The study linked a school in the UK with a school in Norway to engage in computer-mediated collaborative composition via e-mail. Participants were grouped into composing pairs (one from each country) balanced for prior musical experience. Results revealed prior experience of FIMT was associated with extended and complex musical dialogues, critical engagement with musical ideas and produced an ‘exploratory’ environment. No prior experience of FIMT was associated with uncritical and descriptive dialogues and a ‘cumulative’ environment. Proposals for future research are discussed.
Revisiting the frequency of peripheral arterial disease in patients with coronary artery disease: is there a difference between diabetic and non-diabetic patients?
Authors: Papanas  , Tziakas  , Hatzinikolaou  , Chalikias  , Maltezos  , Louridas  , Hatseras
Published: November 2006

Background: The aim of this study was to investigate whether frequency of concomitant peripheral arterial disease (PAD) is associated with angiographic severity of coronary artery disease (CAD), as well as to ascertain if diabetic patients differ from those without diabetes in the association between these two manifestations of atherosclerosis. Patients and methods: This study included 302 patients (229 men, mean age 62.2 ± 11.5 years) with documented CAD, divided into groups I–III, according to the angiographic severity of coronary atherosclerosis. Group I comprised 140 patients (104 men) with severe CAD, group II comprised 63 patients (48 men) with moderate CAD and group III comprised 99 patients (77 men) with mild CAD. Each of the groups I-III was further divided into the subgroups of diabetic and non-diabetic patients. Included were also 88 patients (42 men, mean age 61.7 ± 9.5 years) without CAD and a control group of 60 healthy volunteers (30 men), aged 18–40 years. PAD was diagnosed by means of a Doppler apparatus. Results: Frequency of PAD was associated with angiographic severity of CAD (p = 0.0001). This association was shown both in diabetic (p = 0.012) and in non-diabetic patients (p = 0.0041). Significantly (p ≤ 0.01) higher frequency of PAD among diabetic patients was found in each of the groups I–III. Conclusions: Among patients with CAD, frequency of concomitant PAD is associated with angiographic severity of coronary atherosclerosis. This association is demonstrated both in diabetic and in non-diabetic patients. Finally, PAD is significantly more frequent in diabetic patients, irrespective of the angiographic severity of CAD.
Efficient haemodialysis despite complete central venous thrombosis
Authors: Hecking  , Aschwanden  , Dickenmann  , Thalhammer  , Blum  , Bilecen  , Jaeger
Published: November 2006

Two cases with a fully functional haemodialysis access, in spite of complete thrombotic occlusion of the ipsilateral subclavian and/or brachiocephalic vein are reported. The coincidentally detected complete venous occlusions may indicate that occult venous stenosis or thrombosis is more frequent than generally assumed. In order to avoid deterioration of the haemodynamic situation interventions may be withheld unless clinical problems related to a diminished outflow occur.
Design of an observational strategy for quantifying the Southern Ocean uptake of CO2
Authors: Lenton Andrew , Matear Richard J. , Tilbrook Bronte
Published: November 2006

A sampling strategy to estimate the annual mean CO2 uptake by the Southern Ocean was developed by applying two‐dimensional Fourier transforms and signal‐to‐noise ratios to the simulated air‐sea CO2 fluxes and ΔpCO2 from an ocean biogeochemical model driven with NCEP‐R1. Observations of pCO2 were used to validate the statistical properties of the model and to estimate the mesoscale variability not captured by the model resolution. Sampling regularly every 3 months, at every 30° in longitude and 3° in latitude is sufficient to determine the net Southern Ocean CO2 uptake. We applied this sampling strategy to the simulated air‐sea fluxes to estimate a net annual mean CO2 uptake of 0.6 ± 0.1 PgC/yr (1990–1999). This uncertainty in the estimate was dominated by the simulated interannual variability, and not by errors in the sampling or unresolved mesoscale variability. Therefore sampling at higher resolutions in space and time would not reduce the uncertainty in the Southern Ocean annual mean uptake any further. These results show that a doubling of the current Southern Ocean sampling (in longitude) would be required to constrain the net annual mean air‐sea CO2 fluxes to within the natural variability of the system.