bluuebunny/crossref_metadata_2025 huggingface dataset:
Ether lipids based on the glyceryl ether skeleton: Present state, future potential
Authors: Urata Kouichi , Takaishi Naotake
Published: November 2006

Lipids from natural sources consist mainly of saponifiable substances, such as glycerides, along with some unsaponifiable lipids, some of which are ether lipids. Typical ether lipids are monoalkyl ethers of glycerin, also called alkyl/alkenyl glyceryl ethers. Alkyl/alkenyl glyceryl ethers have also been reported in marine organisms and in human feces. Several chemical syntheses of such ether lipids have been reported. Typical examples are alkyl glyceryl ether formation by the addition reaction of alkyl glycidyl ether and the telomerization reaction of butadiene with glycerin and a transition metal catalyst. Characteristic chemical structures, such as terpene alkyl glyceryl ethers, archaebacterial macrocyclic ether lipids, and glyceryl ethers of condensed cyclic planar molecules, have been obtained as well. Over the past few decades, industry has shown much interest in the chemistry and application of highly branched fatty acids. For example, isostearyl glyceryl ether (GE‐IS) with methyl branching in the middle chain was already known, but it is now prepared at an industrial scale by proprietary alkyl glycidyl ether methods. The characteristic behavior of GE‐IS toward water, such as formation of water‐in‐oil emulsions containing large amounts of water and of liquid crystals, has made it applicable for use in hair and skin‐care cosmetics. Based on these studies and considerations, glyceryl ether lipids, which are rarely investigated, may become one of the most important and useful lipids in the industry.
Synthesis and characterization of cleavable surfactants derived from poly(ethylene glycol) monomethyl ether
Authors: Yue Chengyun , Harris J. Milton , Hellberg Per‐Erik , Bergstrom Karin
Published: November 2006

A series of noncyclic acetal‐linked cleavable surfactants were simply prepared by condensation of aldehydes with poly(ethylene glycol) monomethyl ethers. All of the products were characterized by1H nuclear magnetic resonance. Their hydrophile‐lipophile balance, surface tension, cloud point, critical micelle concentration, and foam height were determined. Hydrolysis kinetic studies, followed by gas chromatography, showed that they had higher hydrolytic reactivity in acidic solution than cyclic acetal‐linked cleavable surfactants.
The bioconversion of ethanol to biosurfactants and dye by a novel coproduction technique
Authors: Osman M. , Ishigami Y. , Someya J. , Jensen Harald B.
Published: November 2006

Rhamnolipids, multifunctional glycolipid biosurfactants, and pyocyanine, a phenazine dye, were coproduced byPseudomonas BOP100 from ethanol as the sole carbon source. Bacterial growth was dependent on the ethanol concentration in the medium. Pyocyanine was produced only during the exponential phase, while rhamnolipids production continued during the stationary phase, indicating two different ways of production for each of the products. Maximum coproduction capacity was observed at a concentration of 3% ethanol; yield of rhamnolipids was 3 g/L, and of pyocyanine 0.2 g/L. The products were characterized to confirm their chemical structures.
An improved falling‐film reactor for viscous liquids
Authors: Talens F. I. , Gutierrez J. M. , Mans C.
Published: November 2006

This paper presents the design of a sulfonation reactor that is intended for enhanced performance when the viscosity of the liquid phase increases, thus reducing gas‐liquid transfer rates. The proposed design allows adequate transfer rates to be maintained by progressively increasing the shear stress exerted by the gas over the liquid film. The effectiveness of the design has been tested in runs in which dodecylbenzene and lauryl alcohol 1.80E are sulfonated/sulfated.
Solubilizing effects caused by the nonionic surfactant octyl glucoside in phosphatidylcholine liposomes
Authors: de la Maza Alfonso , Parra Jose Luis
Published: November 2006

The mechanisms governing the interaction of the nonionic surfactant octyl glucoside (OG) on phosphatidylcholine (PC) liposomes were investigated. Permeability alterations were detected as a change in 5(6)‐carboxyfluorescein (CF) released from the interior of vesicles, and bilayer solubilization was determined as a decrease in the static light scattered by liposome suspensions. A direct relationship was established in the initial interaction steps (10–50% CF release) between the growth of vesicles, the leakage of entrapped CF, and the effective molar ratio of surfactant to phospholipid in bilayers (Re). This dependence was also detected during the solubilization range of Re values between 1.3 and 3.0, where the decrease in the surfactant‐PC aggregate size and in the light scattering of the system depended on the Re parameter and, hence on the composition of these aggregates. The free OG concentrations at subsolubilizing and solubilizing levels showed lower and similar, respectively, values than its critical micelle concentration (CMC). These findings indicated that the alterations in bilayer permeability were due to the action of surfactant monomers, whereas bilayer solubilization was determined by the formation of mixed micelles. This finding supports the generally accepted assumption that the concentration of free surfactant must reach the CMC for solubiliation to occur.
Surface activity and premicellar aggregation of some novel diquaternary gemini surfactants
Authors: Rosen Milton J. , Liu Letian
Published: November 2006

A series of novel cationic gemini surfactants, CnH2n+1 N+(CH3)2CH2CHOHCHOHCH2N+(CH3)2CnH2n+1·2Br−, have been synthesized, and their surface properties were investigated in water, 0.1 N NaCl, and 0.1 N NaBr at 25°C. From surface tension‐log molar concentration plots, the pC20, critical micelle concentration (CMC), and γCMC values have been determined, and the area/molecule at the aqueous solution/air interface was calculated. When the number of carbon atoms in the alkyl (hydrophobic) chains is above a certain number, which depends upon the molecular environment, the surface activity of the compounds is less than expected. This appears to be due to formation of small, soluble aggregates below the CMC. Equilibrium constants calculated for this aggregation indicate that a series of oligomers are formed.
Molar volume and ultrasonic studies of europium soaps in mixed organic solvents
Authors: Mehrotra K. N. , Chauhan M. , Shukla R. K.
Published: November 2006

The ultrasonic velocity and density measurements of europium soaps in a mixture of benzene and methanol (3:2, vol/vol) were used to evaluate various acoustic parameters and molar volume and to determine the critical micelle concentration. The results showed that the ultrasonic velocity, specific acoustic impedance, molar sound velocity, and molar compressibility increase, and intermolecular free length, adiabatic Compressibility, and relative association decrease with increasing concentration and chainlength of the soap. The results were interpreted in terms of soap‐solvent interaction.
Catalytic effect of dipotassium glycyrrhizinate on the hydrolysis of nonionic ester surfactants
Authors: Koide Misao , Takahashi Masahiko , Tamagaki Seizo , Tagaki Waichiro
Published: November 2006

The family of dipotassium glycyrrhizinate (GK2) catalyzes the hydrolysis of nonionic ester surfactants (NES), such as hydrogenated castor oil with 60 oxyethylene units attached (HCO‐60) and monostearate with 25 oxyethylene units attached (SA‐25), even in the pH range of 3–6, where NES are generally stable in the absence of GK2. Long‐chain fatty acids also accelerate the hydrolysis reaction. Analyses, based on circular dichroism spectroscopy, and empirical force field calculations suggest that a GK2 and an NES molecule form an energetically stable complexvia hydrophobic interactions in which the ester carbonyl is in close contact with either one of the three different carboxyl groups in GK2, acting as an acid catalyst.
Dietary triacylglycerol structure and saturated fat alter plasma and tissue fatty acids in piglets
Authors: Innis Sheila M. , Dyer Roger , Quinlan Paul T. , Diersen‐Schade Deborah
Published: November 2006

Human and pig milk triacylglycerols contain a large proportion of palmitic acid (16:0) which is predominately esterified in the 2‐position. Other dietary fats contain variable amounts of 16:0, with unsaturated fatty acids predominantly esterified in the 2‐position. These studies determined if the amount or position of 16:0 in dietary fat influences the composition or distribution of liver, adipose tissue, lung, or plasma fatty acids in developing piglets. Piglets were fed to 18 d with sow milk or formula with saturated fat from medium‐chain triglyceride (MCT), coconut or palm oil, or synthesized triacylglycerols (synthesized to specifically direct 16:0 to the 2‐position) with, in total fatty acids, 30.7, 4.3, 6.5, 27.0, and 29.6% 16:0, and in 2‐position fatty acids, 55.3, 0.4, 1.3, 4.4, and 69.9% 16:0, respectively. The percentage of 16:0 in the 2‐position of adipose fat from piglets fed sow milk, palm oil, and synthesized triacylglycerols were similar and higher than in piglets fed MCT or coconut oil. Thus, the amount, not the position, of dietary 16:0 determines piglet adipose tissue 16:0 content. The effects of the diets on the plasma and liver triacylglycerols were similar, with significantly lower 16:0 in total and 2‐position fatty acids of the MCT and coconut oil groups, and significantly higher 16:0 in the plasma and liver triacylglycerol 2‐position of piglets fed the synthesized triacylglycerols rather than sow milk or palm oil. The lung phospholipid total and 2‐position 16:0 was significantly lower in the MCT, coconut, and palm oil groups, but similar in the synthesized triacylglycerol group and sow milk group. The lung phospholipid total and 2‐position percentage of arachidonic acid (20:4n‐6) was significantly lower in all of the formula‐fed piglets than in milk‐fed piglets. The physiological significance of this is not known.
Isolation and identification of the multiple forms of soybean phytases
Authors: Hamada Jamel S.
Published: November 2006

Sequential precipitation with polyethylene glycol (PEG) and KCl followed by preparative anion exchange high‐performance liquid chromatography was used to isolated acid phosphatases (APases) from germinating soybean seeds. KCl inhibited the PEG precipitation of APases. Thus individual APases can be isolated directly from crude extracts by controlling PEG and KCl concentrations. Four of the isolated APases were phytases. APases 3 and 5 exhibited optimal activity at pH 4.5 and and 5.8. Phytase activity was at its peak at 40°C for APase 4 and at 60°C for APases 3, 5, and 6. This isolation method can be used to identify endogenous and/or exogenous phytases that are suitable for phytic acid hydrolysis in many food and feed systems, especially during the processing. of oilseeds and cereal‐based ingredients.
Characterization of stored regular and low‐linolenic canola oils at different levels of consumer acceptance
Authors: Malcolmson L. J. , Vaisev‐Genser M. , Przybylski R. , Ryland D. , Eskin N. A. M. , Armstrong L.
Published: November 2006

A ten‐member trained sensory panel evaluated regular (RCO) and low‐linolenic (LLCO) canola oils that had been stored at 60°C to four levels of consumer acceptance identified in a prior study. These levels were 70, 60, 50, and 40% acceptance for RCO and 80, 70, 60, and 50% acceptance LLCO. Painty odor intensity increased as consumer acceptance decreased. This same trend was found for chemical measurements of peroxide values, total volatiles, total carbonyls, unsaturated carbonyls, and dienals. These chemical indices were significantly correlated with each other, suggesting that they can be used to monitor related changes in oil quality with respect to lipid oxidation. Values for 19 individual volatiles at each consumer acceptance level were also reported. The data collected in this study provide chemical and sensory characterization of stored RCO and LLCO at distinct levels of consumer acceptance.
Determination of vernolic acid content in the oil ofEuphorbia lagascae by gas and supercritical fluid chromatography
Authors: Borch‐Jensen Christina , Mollerup Jørgen
Published: November 2006

Determination of the content of vernolic acid (12,13‐epoxy‐9c‐octadecenoic) in the oil ofEuphorbia lagascae has been performed by gas chromatography of the fatty acid methyl ester derivatives of the triacylglycerols in the oil and by supercritical fluid chromatography (SFC) of the raw oil and the fatty acid derivatives of the oil. The content of vernolic acid was found to be 55 wt%. The three methods were compared, and SFC analysis of the fatty acid derivatives was found to be the most accurate method.
Singlet oxygen oxidation of lipids resulting from photochemical sensitizers in the presence of antioxidants
Authors: Yasaei Parvin M. , Yang George C. , Warner Charles R. , Daniels Dan H. , Ku Yuoh
Published: November 2006

Singlet oxygen produced by photochemical sensitizers may play an important role in the oxidation of lipids in foods. Therefore, we studied the singlet oxygen oxidation of lipids and the scavenging ability of antioxidants. Singlet oxygen was generated using the photosensitizer rose bengal. The oxidation products of lipids and antioxidants were separated by high‐performance liquid chromatography and monitored using post‐column chemiluminescence and/or iodometric detection. The competitive reaction rates of various antioxidants and lipids were studied to elucidate the roles played by antioxidants in the prevention of food oxidation by singlet oxygen.
Stabilization of seal blubber and menhaden oils with green tea catechins
Authors: Wanasundara U. N. , Shahidi F.
Published: November 2006

Catechins, namely (−)epicatechin (EC), (−)epigallocatechin (EGC), (−)epicatechin gallate (ECG) and (−)epigallocatechin gallate (EGCG), were isolated from commercial Chinese green leaves. The antioxidant activity of isolated catechins was compared with those of α‐tocopherol, butylated hydroxyanisole (BHA), butylated hydroxytolene (BHT) andtert‐butylhydroquinone (TBHQ), all at 200 ppm, in refined, bleached and deodorized seal blubber oil and menhaden oil. The study was carried out under Schaal oven test conditions at 65°C over a 144‐h period, except for weight gain measurements, which were continued for up to 200 h. Progression of oxidation was monitored by measuring changes in weight gain and values of peroxide, conjugated diene, and 2‐thiobarbituric acid‐reactive substances. Oils treated with tea catechins showed excellent oxidative stability as compared with samples that contained commonly used antioxidants, such as α‐tocopherol, BHA, BHT, and TBHQ. The potency of catechins in prevention of oxidation of marine oils was in the decreasing order of ECG> EGCG> EGC> EC; ECG was slightly more effective than TBHQ in systems studied.
Applications of milk‐fat fractions in confectionery products
Authors: Hartel Richard W.
Published: November 2006

Incompatibilities between fats limit the use of modified milk fat in confectionery applications. To further enhance the use of milk‐fat fractions in chocolates and compound coatings, a better understanding of mixed crystallization effects between lipids is required. Recent work documents that highmelting fractions incorporated into chocolates drastically reduce bloom formation and cause less softening than anhydrous milk fat. Isosolids diagrams for mixtures of cocoa butter and milk‐fat fractions show that softening occurs due to both dilution effects and a slight eutectic formation. Incorporation of milk‐fat fractions into palm kernel oil‐based coatings shows some differences with results in chocolates. Milk fat and its fractions cause significant bloom formation in these coatings, as compared to the control, and cause significant softening. However, both milk fat and milk‐fat fractions are fully compatible with palm kernel oil, based on isosolids diagrams. Softening occurs only because of dilution effects, rather than eutectic formation. Further work is necessary to understand the effects of milk‐fat fractions on bloom formation in compound coatings.
Restructuring butterfat through blending and chemical interesterification. 3. Rheology
Authors: Rousseau Dérick , Hill Arthur R. , Marangoni Alejandro G.
Published: November 2006

Interesterified and noninteresterified butterfat‐canola oil blends, ranging from 100% butterfat to 60∶40 butterfat‐canola oil (w/w) in 10% increments, were evaluated for hardness index (HI), dropping point, viscosity, and viscoelastic properties at small deformation. Both blending and chemical interesterification diminished HI in a nonlinear fashion. HI changes in interesterified blends were more pronounced than in noninteresterified blends. Dropping points yielded information on the structure of the blends. Butterfat’s dropping point (DP) was 34.4°C, whereas that of interesterified butterfat was 37.0°C, which is indicative of a more structured network for the latter. DP values of blends with 60–90% butterfat (interesterified vs. noninteresterified) were not significantly different (P<0.05). Interesterified blends had a higher crystallization onset temperature than did noninteresterified blends. All blends in the liquid state displayed Newtonian behavior. Oscillatory frequency sweep measurements at small amplitude showed that interesterified blends generally had lower storage moduli (G′) than their noninteresterified counterparts. BothG′ andG″ were frequency‐dependent. Replacement of 30% butterfat by canola oil led to notable changes in small deformation measurements, whereas replacement of 20% butterfat led to big changes in large deformation measurements.
Is plastic fat rheology governed by the fractal nature of the fat crystal network?
Authors: Marangoni Alejandro G. , Rousseau Dérick
Published: November 2006

The rheological properties of interesterified and noninteresterified butterfat‐canola oil blends do not seem to be strongly related to either solid fat content (SFC) or crystal polymorphic behavior, but rather to the microstructure of the fat crystal network. The microstructure of the fats was quantified by using fractal geometric relationships between the elastic moduli (G′) of the fats and their SFC values using the approach of Shih, W.H., W.Y. Shih, S.I. Kim, J. Liu, and I.A. Aksay [Phys. Rev. A 42:4772–4779 (1990))] for weak‐link regimes. Chemical interesterification decreased the fractal dimension of the fat crystal network from 2.46 to 2.15. We propose that fat microstructure, as quantified by a fractal dimensionality, could be modified to attain specific rheological properties.
Validation of the rancimat test for the assessment of the relative stability of fish oils
Authors: Méndez Eduardo , Sanhueza Julio , Speisky Hernán , Valenzuela Alfonso
Published: November 2006

The induction periods for the peroxidation of various fish oils at 55–90°C were studied by the Rancimat test. The natural logarithms of the induction periods varied linearly with respect to temperature, with a mean coefficient of −7.5×10−2°C−1, which was significantly different from that reported for vegetable oils. The activation energy for the formation of volatile acids had a mean value of 38.9 kJ/mol and was independent of the fish oil source. Peroxide formation under Rancimat test conditions followed first‐order kinetics. The same kinetics were followed under Schaal Oven test conditions (forced‐air oven, 60°C). On the basis of the results obtained, the Rancimat test appears to be useful in determining the relative stabilities of fish oils without the change in peroxide decomposition kinetics that may occur at elevated temperatures.
Crystallization kinetics of the pure triacylglycerols glycerol‐1,3‐dipalmitate‐2‐oleate, glycerol‐1‐palmitate‐2‐oleate‐3‐stearate, and glycerol‐1,3‐distearate‐2‐oleate
Authors: Rousser Ph. , Rappaz M.
Published: November 2006

Crystallization kinetics of the three main components of cocoa butter, the triacylglycerols POP, POS, and SOS (where P, O, and S stand for palmitic, oleic, and stearic acids, respectively) were studied by combined differential scanning calorimetry and polarized light microscopy. The morphologies, nucleation kinetics, growth kinetics, and phases of the grains formed were identified with this system. The experimental data, as well as two different models to simulate crystallization and to predict behavior of the pure triacylglycerols, are presented. The first model is based on a macroscopical approach to solidification by using time‐temperature‐transformation (TTT) diagrams and the additivity principle. It allows prediction of the proportion of the different phases formed for any given thermal path imposed on the sample once the TTT diagram is known for the product. It is illustrated for SOS at constant cooling rates and is compared with experimental results. The second model directly simulates growth of the spherulites in the sample by using nucleation and growth rates that are determined experimentally. It provides a view of the structure as it would be observed with a microscope and shows evolution of the heat released in the sample. Isothermal solidification of POP at 15°C is displayed. The experiment and the model are in good agreement.
Esterification of oleic acid with glycerol in the presence of sulfated iron oxide catalyst
Authors: Guner F. S. , Sirkecioglu A. , Yilmaz S. , Erciyes A. T. , Erdem‐Senatalar A.
Published: November 2006

Esterification of oleic acid with glycerol was investigated in view of the reaction kinetics, using “superacidic” sulfated iron oxide catalysts. A series of different sulfate contents were prepared and characterized by a multitude of techniques prior to their use as catalysts. The sulfated iron oxide reaction was carried out with equivalent amounts of reactants in the temperature range of 180–240°C. Effects of the sulfate content and the catalyst amount on reaction kinetics at different temperatures were evaluated.
Studies on stability of rapeseed wet gum as a source of pharmaceutical lecithin
Authors: Sosada M.
Published: November 2006

Lecithin wet gum with high water content is less stable during storage than dry lecithin. Deoiling and dehydrating the fresh gum can result in a purified lecithin of high quality. The stability of rapeseed wet gum obtained from double‐zero rapeseed varieties was determined at various temperatures. The effect of storage time on volatile substances, acetone insolubles, neutral lipids and acid, iodine, and peroxide values were investigated. The rapeseed wet gum stored a little above 20°C is stable for up to ten days, although in the frozen state (−20°C) no changes in general composition, acid, iodine, and peroxide values were observed during 24 mon of storage.
Antioxidative effect of ethanol tea extracts on oxidation of canola oil
Authors: Chen Z. Y. , Chan P. T. , Ma H. M. , Fung K. P. , Wang J.
Published: November 2006

There is an increasing interest in the biological effects of natural antioxidants present in teas on formation ofin vivo free radicals, carcinogenesis, and atherogenesis. Teas are traditionally classified into six major groups, namely, green, yellow, white, black, dark‐green, and oolong teas. The present study examined the antioxidative activity of ethanol extracts from these six major groups of teas against oxidation of heated canola oil. The oxidation was conducted at 100°C by monitoring oxygen consumption and changes in linoleic and linolenic acids in canola oil. The ethanol extracts of green, yellow, and white teas strongly inhibited oxidation of canola oil compared to butylated hydroxytoluene, probably due to the presence of natural polyphenols. In contrast, oolong teas examined exhibited only moderate antioxidative activity because of the partial destruction of natural polyphenols by semifermentation. The ethanol extracts of black, dark‐green, and ginseng teas studied showed little or no protection to canola oil from lipid oxidation, probably due to the complete destruction of natural polyphenols by fermentation during manufacturing processes.
Transient testing of soy methyl ester fuels in an indirect injection, compression ignition engine
Authors: Purcell D. L. , McClure B. T. , McDonald J. , Basu Hemendra N.
Published: November 2006

An evaluation of the exhaust emissions from a compression ignition engine for fuels composed of 100 and 30% methyl esters of soy oil (SME) is described. These fuels were compared with a low‐sulfur, petroleum #2 diesel fuel in a Caterpillar 3304, prechamber, 75 kW diesel engine, operated over heavy‐ and light‐duty transient test cycles developed by the United States Bureau of Mines. More than 60 h of testing was performed on each fuel. The objective was to determine the influence of the fuels upon diesel particulate matter (DPM) and gaseous emissions. The effect of a modern diesel oxidation catalyst (DOC) also was determined in an effort to minimize emissions. Neat SME produced a higher volatile fraction of the DPM, but much less carbon soot fraction, leading to overall DPM reductions of 23 to 30% for the light‐ and heavy‐duty transients. The DOC further reduced the volatile fraction and the total DPM. The SME fuel reduced gaseous emissions of CO by 23% and hydrocarbons by over 30% without increasing NOx. The DOC further reduced CO and hydrocarbon levels. Mutagenicity of the SME exhaust was low. Results indicate that SME fuel, used with a proper DOC, may be a feasible emission reduction technology for underground mines.
Fatty acid variation in seed oil amongOcimum species
Authors: Angers Paul , Morales Mario R. , Simon James E.
Published: November 2006

Content, fatty acid composition, and glyceride profile of oil from seeds of seven basil (Ocimum sp.) chemotypes were determined. The species studied includedO. basilicum, O. canum, O. gratissimum, andO. sanctum. The oil content ranged from 18 to 26%, with triglycerides comprising between 94 and 98% of extracted neutral lipids. The major acylated fatty acids were linolenic (43.8–64.8%), linoleic (17.8–31.3%), oleic (8.5–13.3%), and palmitic acid (6.1–11.0%). Linolenic acid was similar among the fourO. basilicum chemotypes (57–62%), highest inO. canum (65%), and lowest inO. sanctum (44%). Basil seed oil appears suitable as an edible oil or can be used for industrial purposes, and could be processed in the same way as linseed oil. Preliminary calculations estimate that a hectare of basil could produce from 300 to 400 kg of seed oil.
Solubilization of octafluoronaphthalene by mixed micelles of fluorocarbon and hydrocarbon surfactants in aqueous solutions
Authors: Asakawa Tsuyoshi , Ikehara Junichiro , Miyagishi Shigeyoshi
Published: November 2006

Solubilization of octafluoronaphthalene (OFN) by fluorocarbon and hydrocarbon surfactants in aqueous solutions has been examined to investigate the effects of mixing surfactants and added salt. Diethylammonium perfluoronanoate (DEAPFN) micelles have the most solubilization power toward OFN. The difference in micellar solubilization power will be caused by the hydrophobicity of ionic groups and micellar size. Large positive synergistic effects on solubilization behavior were observed in the DEAPFN‐diethylammonium tetradecyl sulfate mixed micellar systems. Solubilization of OFN depended on the concentrations of added salt and the aggregation number, that is, the micellar size.
Comparative study of conventional and compact detergents
Authors: Sanchez Leal J. , Perez L. , Ribosa I. , Garcia M. T. , Gonzalez J. J.
Published: November 2006

Experimental work has been carried out on conventional and compact detergent formulations. Comparative study has focused not only on the package size but also on the type of builder contained in the finished product. The detergency as a function of dosage and some parameters concerning the environmental impact of each category of formulation also have been evaluated. Soiled (with carbon black/olive oil) cotton and polyester/cotton fabrics have been used to determine the detergency (% soil removal). Considering the overall results obtained, it can be stated that compact tripolyphosphate‐built detergents impose the lowest chemical load upon the environment for the same detergency performance.
α‐sulfonated fatty acid esters: II. Solution behavior of α‐sulfonated fatty acid polyethylene glycol esters
Authors: Okano Tomomichi , Egawa Naoyuki , Fujiwara Masami , Fukuda Masahiro
Published: November 2006

Sodium α‐sulfonated, fatty acid polyethylene glycol monoesters [CmH2m+1CH(SO3Na)COO(C2H4O)nH] and diesters [CmH2m+1CH(SO3Na)COO(C2H4O)nCOCH(SO3Na)CmH2m+1], wherem=10–16 andn=1–35, were prepared by esterification of α‐sulfonated, fatty acids with polyethylene glycols, followed by neutralization with NaOH. Crude products were purified by reversed‐phase column chromatography on an octadecyl‐modified silica gel. Characteristic solution behavior of these α‐sulfonated fatty acid esters was, examined, and the following features were observed. All monoesters prepared in this work had Krafft points below 0°C and also possessed good calcium stabilities. Critical micelle concentrations of the monoesters increased monotonously, as a rule, with an increase in the number of oxyethylene units. These results suggest that the polyethylene glycol residue of the monoester behaves as a hydrophile. On the other hand, diesters possessed high water solubility, low foamability, and critical micelle concentrations that were lower by a factor of ten compared to those of the monoesters.
A comparison of the ethoxylation of a fatty alcohol, fatty acid, and dimethiconol
Authors: O’Lenick Anthony J. , Parkinson Jeffrey K.
Published: November 2006

Knowing that dimethiconols or silanols condense under acid or alkaline catalysis, a study was undertaken to determine if these compounds could be successfully ethoxylated under conditions similar to those used to ethoxylate fatty alcohols and acids. It was anticipated that the condensation reaction would take precedent over ethoxylation reaction. We determined that ethoxylation reaction occurs preferentially to condensation reaction. In addition, kinetics of ethoxylation are similar to kinetics observed when fatty alcohols are ethoxylated. This reaction gives rise to a new class of hydrolyzable silicone compounds that have applications in industrial as well as in personal‐care products.
Nonionic amphiphilic compounds from aspartic and glutamic acids as structural mimics of lecithins
Authors: Allouch Mohamed , Infante Ma Rosa , Seguer Joan , Stebe M.‐Jose , Selve Claude
Published: November 2006

Monodisperse nonionic surfactant molecules, based on aspartic or glutamic acid, with two hydrogenated or fluorinated fatty amide chains in the hydrophobic part and one polyoxyethylene methoxy‐capped chain (EOn−Me) in the hydrophilic head group have been synthesized. These compounds are structural mimics of natural lecithins. Their solubility in water or in formamide and the surface activities at 60°C have been measured and discussed in comparison with lecithin analogues that contained short chains. The compounds reported in this study showed physicochemical properties comparable with those of lecithins.
Activity and stability ofPenicillium cyclopium lipase in surfactant and detergent solutions
Authors: Xia J. , Chen X. , Nnanna I. A.
Published: November 2006

Activity and stability of an alkaline lipase fromPenicillium cyclopium var.album (PG 37) were studied in surfactant and detergent solutions. Three anionic surfactants [Na salts of C12SO4− (sodium dodecyl sulfate), C12ØSO3/− (linear alkyl benzene sulfonate), and C11COO− (laurate)] and four homologous series of nonionic surfactants of C12–15 polyoxethylenated fatty alcohols (AEO3, AEO5, AEO7, and AEO9) were evaluated. At a concentration range of 3.2–40 μM, sodium dodecyl sulfate and laurate stimulated the activity of PG 37 lipase. At concentrations greater than 5.6 μM, linear alkylbenzene sulfonate inhibited PG 37 lipase activity. Nonionic surfactants, AEO5 and AEO7, in the concentration range of 0.25–20 mM, enhanced and stabilized the activity of PG 37 lipase. The presence of PG 37 lipase in detergent formulaton improved detergency ∼20%. The mechanism of inhibition of the lipolytic activity of PG 37 lipase is proposed to be partly due to the formation of inactive (BR)n‐E complex between the hydrophobic moiety of the surfactants and the surface of the lipase. Conversely, formation of a soluble (RB)n‐E complex between the hydrophilic group of the surfactant and lipase may account for the increased lipolytic activity of PG 37 lipase.
Foaming properties of surfactin, a lipopeptide biosurfactant fromBacillus subtilis
Authors: Razafindralambo Hary , Paquot Michel , Baniel Alain , Popineau Yves , Hbid Choukri , Jacques Philippe , Thonart Philippe
Published: November 2006

Foaming properties of surfactin were investigated and compared to those of sodium dodecyl sulfate (SDS) and bovine serum albumin (BSA). Foams were formed by a bubbling technique. Evolution of the foam volume and the liquid in the foam was monitored with optical and conductimetric methods to characterize foam formation and stability. Excellent foaming properties of surfactin were shown by its higher ability to form and stabilize the foam at a concentration as low as 0.05 mg/mL, in comparison with SDS and BSA. Surfactin produced a foam with intermediate maximum density and stabilized the liquid in foam, as well as BSA.
Malaysian red palm oil in a surfactant association structure
Authors: Zaizi D. , Hamdan S. , Dzulkefly K. , Anuar K. , Faujan B. H. A. , Laili C. R.
Published: November 2006

The interlayer spacings of a lamellar liquid‐crystalline structure, before and after incorporation of red palm oil, were determined by means of small‐angle X‐ray diffraction. The results agreed with earlier investigations on refined, bleached, and deodorized palm olein for the anionic host. The cationic host, after addition of red palm oil, showed two features of interest. First, the results showed a drastic decrease of its extrapolated interlayer spacing, and, second, the slope exhibited a value twice that of the host value.
A novel compound, 12,13,17‐trihydroxy‐9(Z)‐Octadecenoic acid, from linoleic acid by a new microbial isolateClavibacter sp. ALA2
Authors: Hou Ching T.
Published: November 2006

A novel compound, 12,13,17‐trihydroxy‐9(Z)‐octadecenoic acid (THOA), was produced from linoleic acid by microbial transformation at 25% yield. The newly isolated microbial strain that catalyzed this transformation was identified asClavibacter sp. ALA2. The product was purified by high‐pressure liquid chromatography, and its structure was determined by1H and13C nuclear magnetic resonance, Fourier transform infrared, and mass spectroscopy. Maximum production of THOA was reached after 85 h of reaction. THOA was not further metabolized by strain ALA2. This is the first report on 12,13,17‐trihydroxy unsaturated fatty acid and its production by microbial transformation.
Enzymatic synthesis of geranyl acetate by transesterification with acetic anhydride as acyl donor
Authors: Yee Lisa N. , Akoh Casimir C.
Published: November 2006

Pseudomonas sp. lipase (PS) was immobilized by adsorption technique onto glass beads and tested for its ability to synthesize geranyl acetate by transesterification with acetic anhydride as the acyl donor. Reactions were carried out inn‐hexane containing 0.1 M geraniol, 0.1 M acetic anhydride, and 200 units of lipase PS. Enzyme load, effect of substrate concentration, added water, temperature, time course, organic solvent, pH memory, and enzyme reuse were studied. Yields of up to 96% were obtained with 200 units (approximately 11% w/w of reactants) of enzyme. Increasing amounts of geraniol inhibited lipase activity, while excess acyl donor concentration enhanced ester production. Yields as high as 97% were obtained at 50°C, 24 h incubation, with no added water. Solvents with logP values ≥3.0 showed the highest conversion yields. Solvent‐free samples also performed well. The pH range of 4–9 gave good yields (92–98.4%). Enzyme reuse studies showed the lipase remained active after 15 runs.
Combined nonenzymatic‐enzymatic method for the synthesis of simple alkyl fatty acid esters from soapstock
Authors: Haas Michael J. , Scott Karen M.
Published: November 2006

Soapstock (SS) is a by‐product of the extraction of oilseeds to produce edible oils. Annual U.S. production exceeds one‐half million tons. A representative sample of SS consists of 45.1% water, 10.0% free fatty acids, 10.1% triglycerides, 1.8% diglycerides, 3.6% phosphatidylethanolamine, 2.2% phosphatidylinositol, 2.7% phosphatidylcholine, 14.0% solvent‐insolubles and 10.5% other material, which was not characterized. A process has been developed that sequentially employs a nonenzymatic and an enzymatic step to convert the lipid‐linked and the free fatty acids of SS to the esters of monohydric alcohols. The first step of the process employed alcohol and potassium hydroxide to transesterify the glyceride‐and phosphoglyceride‐linked fatty acids of the substrate. Because water inhibited the reaction, it was necessary that the SS be dried before use. Nonetheless, even with some batches of SS with water contents below 1% (weight basis), ester hydrolysis accompanied esterification. Each of five examined simple primary alcohols participated effectively in the transesterification reaction, which proceeded rapidly at room temperature and was essentially complete within 1 h. The average ratio of transesterification to hydrolysis in four examined small primary alcohols was 4:1. However, in methanol this value was 99:1 due to the virtual absence of hydrolysis. Significant transesterification by a secondary alcohol (isopropanol) did not occur at room temperature. The minimum effective molar ratio of alcohol to lipid‐linked fatty acids was 20:1. The minimum effective concentration of KOH was between 0.10 and 0.15N. The efficiency of the transesterification reaction exceeded 90% of theoretical maximum. The second step of the process involves lipase‐mediated esterification of the free fatty acids in the preparation that are not esterified by the alkaline transesterfication. Of four lipase preparations examined (Novo Lipozyme IM 20 and SP435, and Amano PS30 and CE), only SP‐435 catalyzed significant esterification of the free fatty acids. The reaction was not catalyzed by heat‐denatured enzyme. In the pH range between 6 and 13.5, the enzyme reaction proceeded best at pH 6, although also well at pH 7. The optimal water concentration was 0.70% (vol/vol). At an enzyme dosage of 1.1% (weight basis, relative to the dry weight of SS present) under optimal conditions and at 42°C, 63% of the free fatty acids in a post‐alcoholysis mixture were enzymatically esterified. The addition of molecular sieves did not increase esterification, which was probably retarded by the high viscosities of the reactions. Under the optimal conditions identified here, the degree of conversion of the fatty acids in SS to simple alkyl esters by the combined reaction scheme was 81%. Opportunities exist for further optimization of these reactions.
Production of docosahexaenoic and docosapentaenoic acids bySchizochytrium sp. isolated from Yap Islands
Authors: Nakahara T. , Yokochi T. , Higashihara T. , Tanaka S. , Yaguchi T. , Honda D.
Published: November 2006

A marine microbe (strain SR21) from the coral reef area of the Yap Islands was isolated by a screening test for polyunsaturated fatty acids and was found to accumulate lipid that contained 22:5n‐6 docosapentaenoic acid (DPA) as well as 22:6n‐3 docosahexaenoic acid (DHA). Strain SR21 was identified as genusSchizochytrium in Labyrinthulomycota, owing to its ultrastructural character and life cycle, which is composed of vegetative cell, zoosporangium, and zoospore stages. After cultural optimization, both in flask and fermenter, the highest DHA and DPA productivities of 2.0 and 0.44 g/L per day, respectively, were obtained in a medium of 60 g/L glucose and corn steep liquor/ammonium sulfate in a half salt concentration of seawater in fermenter culture at 28°C and pH 4. This productivity was almost twice that obtained with flask culture, indicating its high resistance to mechanical stirring. The lipid extracted from the cell was about 50% of the dry cell weight and was composed of 93% triacylglycerol (TG). DHA content of the lipid was 34% of total fatty acids. The TG profile was simple, and the content of the most dominant TG, 1,3‐dipalmitoyl‐2‐DHA‐TG, was 27%. TG that contained DHA and n‐6‐DPA amounted to 57 and 17%, respectively, of total TG molecules. Strain SR21 was revealed to be an excellent source of microbial DHA and n‐6 DPA.
Design and action of steroidal aromatase inhibitors
Authors: Li Shengrong , Parish Edward J.
Published: November 2006

The biosynthesis of estrogens involves three sequential hydroxylations, progressing from cholesterol, that are mediated by an enzyme complex referred to as aromatase. The last steps in this sequence involve aromatization of the A ring of the steroid nucleus. Compounds that inhibit aromatase have potential applications in the treatment of advanced estrogen‐dependent mammary carcinoma and prostatic hyperplasia. The enzyme aromatase is currently a priority target for the development of active‐site directed inhibitors. A number of steroid inhibitors may inactivate aromatase by diverse interactions with the enzyme and include competitive inhibitors, affinity labelling agents, and mechanism‐based inhibitors (“suicide substrates”). By designing steroidal analogs with substituents at various positions on the steroid nucleus, information has been obtained on the structural requirements needed for favorable interactions with the enzymatic sites.
Sugar ester‐modified lipase for the esterification of fatty acids and long‐chain alcohols
Authors: Basheer Sobhi , Nakajima Mitsutoshi , Cogan Uri
Published: November 2006

The esterification reaction of a long‐chain fatty acid and a fatty alcohol with a surfactant‐modified lipase in a microaqueousn‐hexane system was studied. Various lipases from different sources were first modified with a surfactant of the sugar ester type to improve their dispersibility in apolar organic solvents. This enzyme modification technique converted inactive crude lipases to highly active biocatalysts for the esterification of long‐chain fatty acids and fatty alcohols in a microaqueous n‐hexane system. The hydrophilic‐lipophilic balance value and chainlength of the fatty acid residue of the fatty acid sugar ester, used for modifying the lipases, significantly influenced the amount of precipitated lipase that was dissolved in the aqueous solution, the protein content of the lipase‐surfactant complex and its esterification activity.
Application of lipases to the regioselective synthesis of sucrose fatty acid monoesters
Authors: Sarney Douglas B. , Barnard Mark J. , MacManus David A. , Vulfson Evgeny N.
Published: November 2006

A regioselective synthesis of 6′‐O‐acyl sucrose monoesters has been developed through the lipase‐catalyzed esterification of sucrose acetals with fatty acids in both organic solvents and under solvent‐free conditions. The products were obtained in overall yields of 20–27% after hydrolysis of the isopropylidene groups with aqueous acids. The strict selectivity of the enzymes used also enabled the preparation of a monoester fraction that was highly enriched in 6‐O‐acyl sucrose. This was accomplished by lipase‐catalyzed transesterification of sucrose monoesters, prepared by conventional chemical methods, in propan‐2‐ol. After removal of the transesterification products (sucrose and fatty acid isopropyl esters) and column chromatography on silica gel, the obtained monoester product contained 80% of the single regioisomer, 6‐O‐acyl sucrose.
Synthesis of medium‐chain glycerides by lipase in organic solvent
Authors: Kwon Dae Young , Song Hyo Nam , Yoon Suk Hoo
Published: November 2006

Using commercial lipases from various microbial origins, medium‐chain glycerides, such as mono‐, di‐, and tricaprin, were synthesized in isooctane from glycerol and capric acid. The enzyme reaction was performed with 0.35 M capric acid, 0.025 M glycerol, and 0.46 g silica gel to remove water in 5 mL of isooctane with 30 mg lyophilized lipase. Of the 21 kinds of lipases, 11 showed good synthetic activities. Lipases fromPseudomonas aeruginosa (Lipase PS),Rhizomucor miehei lipase andChromobacterium viscosum lipase (Lipase CV) showed high activities for the production of tricaprin, while lipase OF‐360 (fromCandida rugosa) and lipase D (Rhizopus delemar) were good for dicaprin production. Lipases CC and MY fromC. rugosa (C. cylindracea) and lipase D (Rhizopus delemar) were good for dicaprin production. Lipases CC and MY fromC. rugosa (C. cylindracea) also showed high activities for dicaprin and tricaprin. Some lipases, especially lipase PS, had high thermal stability over 60°C. The optimal lyophilization pH to dehydrate the lipase coincides with the optimal buffer solution pH for hydrolysis.
Esterification and interesterification reactions catalyzed by acetone powder from germinating rapeseed
Authors: Jachmanián I. , Mukherjee K. D.
Published: November 2006

Acetone powder from germinating rape (Brassica napus L.) seedlings exhibits essentially similar activity in lipolysis of triacylglycerols as the corresponding seedling homogenates. Acetone powder from rape seedlings catalyzes the esterification of a fatty acid, such as oleic acid, withn‐butanol or a long‐chain alcohol, such as oleyl alcohol. Furthermore, the acetone powder catalyzes alcoholysis of a methyl ester, such as methyl oleate withn‐butanol or oleyl alcohol, and acidolysis of methyl oleate with a fatty acid, such as erucic acid. However, triacylglycerols are not accepted as substrates fro interesterification reactions. In esterification of fatty acids withn‐butanol, catalyzed by the acetone powder from rape seedlings, fatty acids having an olefinic bond next to the carboxyl group as acis‐6 double bond, e.g., γ‐linolenic, gorlic and petroselinic acids, or those having acis‐4 double bond, e.g., docosahexaenoic acid, are strongly discriminated against as substrates. Such substrate selectivities can be utilized for the enrichment of definite fatty acids from mixtures, derived from naturally occurring oils,via kinetic resolution.
Distribution of Δ5‐olefinic acids in the triacylglycerols fromPinus koraiensis andPinus pinaster seed oils
Authors: Gresti Joseph , Mignerot Corinne , Bézard Jean , Wolff Robert L.
Published: November 2006

Purified triacylglycerols (TAG) fromPinus koraiensis andP. pinaster seed oils, which are interesting and commercially available sources of Δ5‐olefinic acids (i.e.,cis‐5,cis‐9,cis‐12 18:3 andcis‐5,cis‐11,cis‐14 20:3 acids) were fractionated by reversed‐phase high‐performance liquid chromatography, and each fraction was examined by capillary gas‐liquid chromatography for its fatty acid composition. A structure could be assigned to more than 92% of TAG from both oils. In both instances, ca. 48% of the TAG were shown to contain at least one δ5‐olefinic acid. In the great majority of TAG, our data showed that there is only one molecule of δ5‐olefinic acid per molecule of TAG. This is compatible with theoretical calculations based on the proportion of total δ5‐olefinic in the oils. Thecis‐5,cis‐9,cis‐12 18:3 acid (14.2 and 8.6% of total fatty acids in the seed oils ofP. koraiensis andP. pinaster, respectively) and thecis‐5,cis‐11,cis‐14 20:3 acid (1.1 and 8.1% of total fatty acids in the seed oils ofP. koraiensis andP. pinaster, respectively) are preferentially associated with two molecules of linoleic acid, and to a lesser extent, to one molecule of linoleic acid and one molecule of oleic acid, or two oleic acid molecules. However, several other combinations occur, each in low amounts. The distribution of δ5‐olefinic acids in TAG is evidently not random. Combining these results with the known preferential esterification of δ5‐olefinic acids to the 1,3‐positions of TAG would suggest that most of these acids are present at only one of these positions at a time.