bluuebunny/crossref_metadata_2025 huggingface dataset:
Nonbuilt heavy duty liquids: Detergency and formulating parameters
Authors: McGuire S. E. , Matson T. P.
Published: January 2007

The detergency of nonbuilt heavy duty liquids containing linear alkylate sulfonate and/or linear alcohol ethoxylate nonionic active is discussed. Single cycle detergency on a broad range of linear alkylate sulfonate‐nonionic compositions was evaluated on cloths soiled in the laboratory with a mixture of synthetic sebum and dust and a commercially available soiled cloth, ACH #120A. The effects of multiple cycle wash testing also were covered. Formulating parameters to produce usable nonbuilt heavy duty liquids are discussed. The nonionic of choice for maximum detergency in nonbuilt heavy duty liquids should be derived from ca. a 14 carbon chain length alcohol with ca. 70% ethylene oxide. For optimum solubility, linear alkylate sulfonate should be the sodium salt derived from a linear alkylbenzene of ca. 235–240 mol wt, a product like that currently used in light duty liquids. The presence of linear alkylate sulfonate in nonbuilt heavy duty liquids helped reduce product clear point. Nonionics were found to give the best performance on cotton cloth. Linear alkylate sulfonates were most effective on synthetics. Multiple cycle testing with Spangler soil on nonbuilt heavy duty liquids was shown to be unnecessary. Mixed active systems gave the best overall product on the basis of performance and physical properties.
Effects of feeding formaldehyde treated, full fat soybean flours on milk fat polyunsaturated fatty acids
Authors: Bitman J. , Wrenn T. R. , Wood D. L. , Mustakas G. C. , Baker E. C. , Wolf W. J.
Published: January 2007

Raw, commercial, and extrusion cooked full fat soy flours were treated with formaldehyde and then fed to dairy cows. This treatment protected the polyunsaturated fats of the soy from hydrogenation by microbial action in the cow’s rumen. With all of these materials, higher than usual amounts of polyunsaturated fats were incorporated into the milk. In a screening test limited to one cow, an advantage as measured by milk yield, fat yield, protein, solids‐not‐fat, and increased milk fat C18:2 was seen for the formaldehyde treated, full fat soy flour. The percentage of linoleic acid more than doubled in the milk fat of cows receiving the protected products. Only very slight quantities of formaldehyde (0.1–0.2 ppm) were found in the milk. The efficiency of transfer of the C18:2 from the feed to milk was ca. 37%. This represented a marked improvement over previous trials in which we fed expensive safflower oil‐casein‐formaldehyde supplements.
Gas density balance versus flame ionization detector
Authors: van der Plank P.
Published: January 2007

Comments are made on a paper by Lanser, et al., comparing the flame ionization detector with the gas density balance for quantitative gas liquid chromatography (GLC) analysis of a mixture of aldehydes and aldehydic esters. The suggestion that a gas density balance should be preferred to a flame ionization detector, according to our experience, is not very convincing and requires more supporting evidence.
Proton nuclear magnetic resonance rapid and structure‐specific determination ofω‐3 polyunsaturated fatty acids in fish lipids
Authors: Sacchi Raffaele , Medina Isabel , Aubourg Santiago P. , Addeo Francesco , Paolillo Livio
Published: January 2007

Based on proton nuclear magnetic resonance (1H‐NMR) spectroscopy, a rapid and structure‐specific method for the determination of ω‐3 polyunsaturated fatty acids (PUFAs) in fish lipids is presented. The different chemical shift observed for the methyl resonance of ω‐3 PUFAs (δ=0.95 ppm) with respect to the methyl resonance of all other fatty acids (δ=0.86 ppm) has provided the possibility of proposing a new and rapid method for the determination of ω‐3 PUFA content. Twenty‐four fish lipid samples (raw, cooked and canned albacore tuna) produced results that showed good agreement between1H‐NMR analysis and gas chromatographic determination. Raw and cooked samples showed significantly higher levels of ω‐3 PUFA than canned tuna.
Sunflower oil used for frying: Combination of column, gas and high‐performance size‐exclusion chromatography for its evaluation
Authors: Sánchez‐Muniz F. J. , Cuesta C. , Garrido‐Polonio C.
Published: January 2007

The alterations of a sunflower oil were evaluated by column, gas and high‐performance size‐exclusion chromatography after being used for deep‐fat frying fifteen repeated and discontinuous times. Polar compounds increased significantly (6.2 ± 0.3% to 18.7 ± 0.8% in oil). Linoleic acid decreased (53.8 ± 0.2 to 48.1 ± 0.8 mg/100 mg oil) while oleic acid remained unaltered after 15 fryings. Saturated fatty acids such as palmitic and stearic, also remained unaltered. Triglyceride polymers (0.1 ± 0.0 to 2.4 ± 0.2 mg/100 mg oil), triglyceride dimers (1.0 ± 0.2 to 6.7 ± 0.3 mg/100 mg oil) and oxidized triglycerides (3.4 ± 0.2 to 7.6 ± 0.3 mg/100 mg oil) increased significantly in the oil used 15 times to fry potatoes. These thermoxidative compounds correlated well with the number of fryings (r=0.9864, r=0.9535 and r=0.9758, respectively). Diglyceride compounds remained unaltered, while free fatty acids increased from 0.4 ± 0.0 to 0.6 ± 0.0 mg/100 mg oil. Both of these, which are characteristic of hydrolytic alteration, did not correlate significantly (r=0.5985 and r=0.4261, respectively) with the number of fryings. These data suggest that a thermoxidative process, rather than a hydrolytic one, took place in this study.
On the kinetics of the autoxidation of fats
Authors: Brimberg Ulla I.
Published: January 2007

The mechanism of fat autoxidation is elucidated from the rate data. All the data treated here and in an earlier publication follow the same basic rate equation, including the time function f(t) empirically derived for heterogeneous oxidation. Metals and glass (the wall of the reaction vessel) are catalysts. Depending on the state of the catalyst, f(t)=t2 or f(t)=t. When f(t)=t, the kinetics are first‐order as found for monolayer autoxidation, but in bulk phase they are complicated by a transient stage caused by the solubilization of O2 into the hydroperoxide micelles produced in the exponential (“autocatalytic”) part of the oxidation. Certain additives, such as inhibitors, affect the catalyst and thereby f(t). The kinetics, as determined by O2 consumption or by analysis of the remaining unreacted substrate, show the first oxidation step. It is unaffected by further chemical changes of the primary oxidation products,e.g., decomposition of hydroperoxides and trimerization in the autoxidation of 9,11‐octadecadienoic acid methyl ester.
Enzymatic pretreatment of deodorizer distillate for concentration of sterols and tocopherols
Authors: Ramamurthi Suresh , McCurdy Alan R.
Published: January 2007

Separation of sterols and tocopherols from fatty acids in deodorizer distillate was facilitated through lipase‐catalyzed modification of fatty acids in canola, mixed and soya deodorizer distillates. The fatty acid esterification with methanol catalyzed by SP‐382 (an immobilized nonspecific lipase) proceeded rapidly, with conversion of fatty acid to methyl ester in 5 h being 96.5, 83.5 and 89.4%, respectively. A model mixture of pure oleic acid and dl‐α‐tocopherol was used to study any potential side reactions that may lower the tocopherol content during the esterification reaction. Under the conditions employed, the loss of tocopherol was less than 5%. Simple vacuum distillation (1–2 mm Hg) was employed to remove the volatile fraction (methyl esters of fatty acids, some fatty acids and other volatiles) of the esterified deodorizer distillate, leaving behind sterols, sterol esters and tocopherols. Sterols and tocopherols were almost completely retained in the residue fraction with recoveries in the range of 95%. Overall recoveries of sterols and tocopherols after esterification and distillation were over 90% for all the deodorizer distillate samples.
Behavior of chlorophyll derivatives in canola oil processing
Authors: Suzuki Kiyoji , Nishioka Akira
Published: January 2007

Chlorophyll derivatives in canola oil were analyzed quantitatively by reversed‐phase high‐performance liquid chromatography without any pretreatment. The main components were pheophytin (pheo) a and b and pyropheophytin (pyro) a and b. The factors affecting the types and concentration of chlorophyll derivatives in oil have been investigated during seed preparation, expelling, extraction, degumming and alkali‐refining processes. Bleaching tests of alkali‐refined canola oil with activated earth indicated the adsorption of each derivative to decrease in the following order: pheo a > pyro a >> pheo b > pyro b. In bleaching with activated carbon, however, the following order was observed: pyro b > pheo b > pheo a > pyro a.
Effect of temperature on linolenic acid loss and 18:3 Δ9‐cis, Δ12‐cis, Δ15‐trans formation in soybean oil
Authors: O’Keefe Sean F. , Wiley V. A. , Wright D.
Published: January 2007

Oil was extracted from soybeans, degummed, alkalirefined and bleached. The oil was heated at 160, 180, 200, 220 and 240°C for up to 156 h. Fatty acid methyl esters were prepared by boron trifluoride‐catalyzed transesterification. Gas‐liquid chromatography with a cyanopropyl CPSil88 column was used to separate and quantitate fatty acid methyl esters. Fatty acids were identified by comparison of retention times with standards and were calculated as area % and mg/g oil based on 17:0 internal standard. The rates of 18:3ω3 loss and 18:3 Δ9‐cis, Δ12‐cis, Δ15‐trans (18:3c,c,t) formation were determined, and the activation energies were calculated from Arrhenius plots. Freshly prepared soy oil had 10.1% 18:3ω3 and no detectable 18:3c,c,t. Loss of 18:3ω3 followed apparent first‐order kinetics. The first‐order rate constants ranged from .0018±.00014 min−1 at 160°C to .083±.0033 min−1 at 240°C. The formation of 18:3c,c,t did not follow simple kinetics, and initial rates were estimated. The initial rates (mg per g oil per h) of 18:3c,c,t formation ranged from 0.0031±0.0006 at 160°C to 2.4±.24 at 240°C. The Arrhenius activation energy for 18:3ω3 loss was 82.1±7.2 kJ mol−1. The apparent Arrhenius activation energy for 18:3c,c,t formation was 146.0±13.0 kJ mol−1. The results indicate that small differences in heating temperature can have a profound affect on 18:3c,c,t formation. Selection of appropriate deodorization conditions could limit the amount of 18:3c,c,t produced.
Synthesis and properties of cationic surfactants containing a disulfide bond
Authors: Pinazo A. , Diz M. , Solans C. , Pés M. A. , Erra P. , Infante M. R.
Published: January 2007

Two new cationic surfactants containing a disulfide bond were synthesized, and the physical chemical characteristics and the fundamental surface‐active properties were determined. These new surfactants have potential applications in the textile and cosmetic field. These compounds have been prepared by condensation of a commercial Nα,Nα‐dimethyl amino betaine with cystine dimethyl ester or cystamine by means of the mixed anhydride method. The study of their properties revealed that these molecules are soluble in water (stable at pH≤8) and show surface activity with similar low critical micelle concentration values. Microscopic examination of water/surfactant systems containing these compounds shows that they form liquid crystals with patterns corresponding to typical hexagonal and lamellar structures.
Synthesis of alkyl glycoside fatty acid esters in non‐aqueous media byCandida sp. lipase
Authors: Mutua Lydia N. , Akoh Casimir C.
Published: January 2007

Alkyl glycoside fatty acid esters were successfully synthesized by lipase‐catalyzed transesterification of methyl glucoside, methyl glucoside, methyl galactoside and octyl glucoside with methyl oleate. The experiments were carried out in organic media with lipase enzymes fromCandida sp. as biocatalysts. Time course and the effects of temperature, solvent type, substrate concentration, added water and of immobilizedvs. nonimmobilized enzyme were studied. The optimal conditions for the enzymatic synthesis of alkyl glycoside fatty acid esters were: a molar ratio of alkyl glycoside and methyl oleate of 1:4, an immobilized lipase, SP382 fromCandida sp.; benzene/pyridine (2:1, vol/vol) with no added water; temperature, 55°C; reaction time, 48 h; and shaking at 200 rpm. Acceptable levels of oleic acid incorporation (58.6–100 mol%) onto the alkyl glycosides were achieved.
Influence of calcium concentration in the washing liquor on detergency performance of linear alkylbenzene sulfonate
Authors: Cohen L. , Moreno A. , Berna J. L.
Published: January 2007

The effect of the concentration of linear alkylbenzene sulfonate (LAS) on soil removal efficiency at various water hardnesses was studied. The present investigation indicates that: (i) For each LAS concentration, a calcium ion concentration interval exists, defined by 0.78<(Log(LAS)/Log(Ca))<0.85, where the detergency reaches a maximum; (ii) 24 h after having been prepared, the solutions present either clear solutions (water appearance), milky solutions (without precipitate in the bottom of the bottle), or clear solutions with precipitate in the bottom of the bottle. The milky solutions correspond to the defined interval. The solutions where the relationship LAS/Ca is defined are located, surprisingly in a precise zone of the LAS‐calcium solubility diagram. The study has been carried out with and without ionic strength buffering, and the addition of electrolyte moves the maximum detergency performance interval to higher calcium concentrations.
Heterocyclic compounds derived from aliphatic amines
Authors: Foglia T. A. , Maerker G.
Published: January 2007

The photolytic rearrangement of N‐chloroamines derived from secondary fatty amines, such as N‐methyloctadecylamine, has been investigated. The intermediate δ‐ or ε‐chloroamines, or both, were not isolated from the reaction medium but were converted directly to their corresponding N‐methyl‐2‐alkylpyrrolidine or piperidine analogs, or both, by treatment with alkali. The synthetic utility of this reaction has been extended to include the two functionally substituted secondary amines, N,N‐dimethylazelaylamine and methyl 11‐methylaminoundecanoate. The yields of isolated pure products are in the range of 50–80%.
The thermal alkylation of phenol with olefins
Authors: Anderson R. G. , Sharman S. H.
Published: January 2007

Linear alkylphenols from α‐olefins can be made by reaction at 260–425 C without added catalyst. By proper choice of conditions, up to 95% monoalkylphenol having the phenol moiety attached at the 1‐and 2‐carbon of the side chain (primarilyortho orientation) can be obtained.
Changes in oil‐type sunflowerseed stored at 20 C at three moisture levels
Authors: Robertson J. A. , Roberts R. G. , Chapman G. W.
Published: January 2007

Oil‐type hybrid sunflowerseed held at 63%, 83% and 93% relative humidities (RH) at 20 C attained equilibrium moisture contents (mc) of 6.7 ± 0.1%, 9.8 ± 0.1% and 13.4 ± 0.3%, respectively, and were stored under these conditions for up to 60 weeks (wk). Germinability was inversely related to both storage duration and RH. Initially, the seed contained only field fungi (mainlyAlternaria spp. andPhoma macdonaldii) and 0.5% free fatty acids (FFA). At 6.7% mc, the amount ofAlternaria spp. andP. macdonaldii isolated declined slowly with time, storage fungi did not invade the seed, and FFA in extracted oil did not change significantly during 60 wk storage. No significant correlation was found between FFA, germination, mold count (cfu/g) or fungi recovered. At 9.8% mc, field fungi declined more rapidly than at 6.7% mc, storage fungi (mainlyEurotium rubrum andE. repens) were isolated from the seed after 4 wk, and FFA increased to 2.5% after 40 wk. FFA content was negatively correlated with germination (r=−0.91) and withAlternaria alternata (r=−0.90) but was positively correlated withE. rubrum (r=0.78). At 13.4% mc, field fungi vanished and storage fungi invaded the seed more rapidly than at 9.8% mc, and FFA increased to 6.3% after 24 wk storage. FFA content was positively correlated with storage fungi such asAspergillus versicolor (r=0.74) and negatively correlated with germination (r=−0.88) andA. alternata (r=−0.82). After 14 wk storage the fungus recovered most frequently wasA. versicolor, followed byEurotium rubrum, E. repens, A. alternata, E. amstelodami, Penicillium spp. andMalbranchea sulphurea.
Rapid separation of free sterols by reversed‐phase high performance liquid chromatography
Authors: Holen Børge
Published: January 2007

The separation of eight common, structurally closely related sterols on C8 and C18 reversed‐phase columns with UV‐detection at 206 nm is described. Good separation was obtained in less than 18 min on the C18 column using methanol‐water as mobile phase and a column temperature of 30 C. Except for brassicasterol and cholesterol, the sterols also were readily separated on the C8 column. Applications of the method on sterols from natural sources are described.
Alkaline cortaminant materials in used frying oils: A new quick test
Authors: Blumenthal M. M. , Stockler J. R. , Summers P. J.
Published: January 2007

The AOCS recommended practice Cc 17–79 measures titratable alkalinity (soaps) at the low parts per million level in fresh, alkalirefined vegetable oils. This method indicated that titratable alkalinity is present at levels equivalent to many parts per million of “soap” in used frying oils. A colorimetric quick test was developed to show the presence and semi‐quantitative concentration of alkaline contaminant materials (ACM), such as soap, in two types of fresh and used frying oils. The quick test works with fresh and used vegetable and animal/vegetable oil blends where it is not possible to use Cc 17–79.
Antioxidant effects of chlorophyll and pheophytin on the autoxidation of oils in the dark. I. Comparison of the inhibitory effects
Authors: Endo Yasushi , Usuki Richiro , Kaneda Takashi
Published: January 2007

The effects of chlorophyll and pheophytin on the autoxidation of oils in the dark were investigated by oven tests. The results indicated that both chlorophyll and pheophytin show antioxidant activity when methyl linoleate is used as substrate. Furthermore, chlorophyll retarded the oxidative deterioration of triglycerides in rapeseed and soybean oils at 30 C. Among the four chlorophyll derivatives (chlorophylls a and b and pheophytins a and b), chlorophyll a showed the strongest antioxidant activity. The antioxidant effects of chlorophyll and pheophytin depended on the storage temperature and the kinds of oil used as substrate.
Interactions between linear alkylbenzene sulfonates and water hardness ions. I. Effect of calcium ion on surfactant solubility and implications for detergency performance
Authors: Matheson K. Lee , Cox Michael F. , Smith Dewey L.
Published: January 2007

This paper examines the interactions of linear alkylbenzene sulfonate (LAS) surfactants with calcium ions. Calcium sulfonate precipitation boundary diagrams are given which provide a convenient way to study these interactions over a wide range of surfactant and hardness ion levels. Some implications of these interactions for detergency performance are discussed.
Rheological characteristics of a detergent slurry containing pentasodium triphosphate
Authors: Guerrero A. F. , Rodríguez Patino J. M. , Albea L. , Flores V. , Gallegos C.
Published: January 2007

The purposes of the present work are to analyze the rheological characteristics of a detergent slurry containing pentasodium triphosphate (TPP) and to study the influence that some factors exert on the rheological consistency of this slurry. Experimental results were achieved using a Brabender Plastograph and have been analyzed according to approximate methods to convert torque‐rheometer data into fundamental rheological units.

From the experimental results it can be inferred that: (i) The systems studied exhibit plastic rheological behavior at steady shear and a progressive decrease in consistency by increasing shear rate; (ii) an increase in the yield value and apparent viscosity of the slurry are produced by increasing the concentration of nonaqueous substances or the phase I/phase II TPP ratio; and by decreasing the temperature or the hydrotrope content; (iii) the effect that temperature and concentration exert on the rheological consistency of the slurry may be quantified according to the usual equations found in the references.
Noncarotenoid hydrocarbons in palm oil and palm fatty acid distillate
Authors: Goh S. H. , Gee P. T.
Published: January 2007

Column chromatographic and gas chromatographic‐mass spectroscopic (GCMS) analyses for minor and trace noncarotenoid hydrocarbons of crude palm oil and palm fatty acid distillate revealed the presence of a wide range of n‐alkanes (C12H26to C36H74) and n‐alkenes in addition to the major component, squalene. Hydrocarbon components concentrated in palm fatty acid distillate where squalene was dominant, but degradation products such as alkenes (from fatty acids or glycerides), aromatic hydrocarbons (from carotenes) and diterpene hydrocarbons (from tocotrienols) were detected in significant quantities, superseding the naturally occurring n‐alkanes. Mechanisms proposed suggest that degradation of the valuable vitamin E or tocotrienols needs to be minimized in physical refining.
Effect of food emulsifiers on polymorphic transitions of cocoa butter
Authors: Garti Nissim , Schlichter Judith , Sarig Sara
Published: January 2007

The polymorphic behavior of cocoa butter in the presence of several food emulsifiers serving as crystal structure modifiers was investigated. Emphasis was placed on transitions among the relatively stable forms IV, V and VI, which are significant for a confectionery industry.

As known from industry work, within the series of sorbitan esters and ethoxylated sorbitan esters, the solid emulsifiers were the most efficient in retarding transition of V form into VI modification. Blends of sorbitan monostearate (Span 60), ethoxylated sorbitan monostearate (Tween 60) and Span 60‐Tween 65 used in the present study were particularly effective. Surprisingly, it was found that some combinations of emulsifiers accelerate the transition of form IV into form V. Transition of form V into form VI occurs via the solid state, and other transitions are known to take place via the liquid phase. Emulsifier was found to increase liquid fraction of the fat prior to its transition. Mechanistic considerations concerning these transitions are suggested.
Adulterated butterfat: Fatty acid composition of triglycerides and 2‐monoglycerides
Authors: Soliman Mervat A. , Younes N. A.
Published: January 2007

Beef tallow and cottonseed oil were mixed with a pure butterfat in the ratios of 2%, 4% and 6% to obtain admixtures of beef tallow with butterfat and cottonseed oil with butterfat. The hydrolysis of individual triglycerides was carried out using the lipase to obtain 2‐monoglycerides. The results indicated that butterfat had a higher percentage of C14:0 and C16:0 acids than found in the triglycerides and 2‐monoglycerides of beef tallow and cottonseed oil.

Beef tallow contained a higher proportion of C18:0 and C18:1 acids than butterfat and cottonseed oil triglycerides or 2‐monoglycerides. Cottonseed oil had a higher percentage of C18:2 acid located in triglyceride or 2‐monoglyceride than found in butterfat or beef tallow triglycerides and 2‐monoglycerides.

The analysis of the samples of butterfat containing 2%, 4% and 6% beef tallow revealed that the addition of beef tallow to butterfat affected the fatty acid composition of butterfat triglycerides and 2‐monoglycerides with C18:0 and C18:1 acids; the effect was increased with increasing percentages of beef tallow.

The addition of cottonseed oil to butterfat in the ratios of 2%, 4% and 6% affected the fatty acid composition of butterfat triglycerides and 2‐monoglycerides. It was found that both C18:1 and C18:2 increased as the added cottonseed oil percentages increased.
Retardation of rancidity in deep‐fried instant noodles (ramyon)
Authors: Rho K. L. , Seib P. A. , Chung O. K. , Chung D. S.
Published: January 2007

The storage stability of instant fried noodles (ramyon) was determined by accelerated aging at 63 C with organoleptic evaluation of the onset of rancidity. Three methods of extending the shelf‐life of ramyon were examined: (a) addition of 200 ppm antioxidant, butylated hydroxyanisole (BHA), t‐butylhydroquinone (TBHQ), or a polymeric antioxidant (Poly‐A) to the frying (palm) oil; (b) coating the inner surface of the polyethylene package with TBHQ equivalent to 200, 500 and 1000 ppm based on the oil in the ramyon; and (c) addition of a mixture of 200 ppm TBHQ and 200 or 500 ppm disodium ethylene‐diaminetetraacetate (EDTA) to the frying oil. When the antioxidants were added to the oil, BHA and Poly‐A approximately doubled while TBHQ tripled the shelf‐life of ramyon. The mixture of TBHQ (200 ppm) and disodium EDTA (500 ppm) in the frying oil quintupled the shelf‐life. The inner surface application of TBHQ (200 ppm) extended shelf‐life twice that of an equal amount of TBHQ in the frying oil. Rancid off‐flavors developed slowest in noodles with aw 0.3. Hexanal concentration in ramyon was a good indicator of the development of oxidative rancidity. Organoleptic evaluation showed the flavor of ramyon was objectionable when hexanal concentration reached 3.5 ppm based on the weight of ramyon (as is). The relative effectiveness of antioxidants in preventing off‐flavor in ramyon could be determined from the hexanal concentration in stored ramyon.
Low‐calorie triglyceride synthesis by lipase‐catalyzed esterification of monoglycerides
Authors: McNeill G. P. , Sonnet P. E.
Published: January 2007

Monoglycerides of erucic acid (C22:1, Δ13), prepared by conventional methods, were reacted with caprylic acid (octanoic acid, C8.0) by using lipases as catalysts with the intention of synthesizing a triglyceride that contains two molecules of caprylic acid and one molecule of erucic acid (caprucin). The reaction was carried out by mixing lipase powder, a small quantity of water, and the reactants in a temperature‐controlled stirred batch reactor. Organic solvents or emulsifying agents were not required. When the nonspecific lipase fromPseudomonas cepacia was used, a yield of approximately 37% caprucin was obtained, together with a complex mixture of di‐ and triglycerides that resulted from the random transesterification of the erucic acid. The fatty acid‐specific lipase fromGeotrichum candidum promoted minimal transesterification of erucic acid and resulted in a yield of 75% caprucin and approximately 10% interesterification products. Lipase fromCandida rugosa exhibited a similar, although less pronounced, specificity to that fromG. candidum and promoted more transesterification of erucic acid. Optimum conditions forG. candidum lipase were at 50°C and an initial water content of 5.5%. After the reaction, erucic acid was converted to behenic acid by hydrogenation, thereby converting caprucin into caprenin, a commercially available low‐calorie triglyceride.
Invert emulsion as a medium for fungal lipase activity
Authors: Mozaffar Zahid , Weete John D.
Published: January 2007

An extracellular lipase from the fungusPythium ultimum was active in an invert [water‐in‐oil] emulsion consisting of 4% water emulsified into edible oils with taurocholic acid as the surfactant. The pH range for optimum lipolytic activity was 7.5–8.5, and the optimum temperature for activity was 45°C. Specific activity of the purified lipase was 919.5 µmol/min/mg protein in the invert emulsion. Water content of the invert emulsion influenced activity of the lipase differently, depending on the substrate. The rate of olive oil hydrolysis with thePythium lipase decreased with time, possibly due to inactivation of the enzyme and inhibition by free fatty acid products of the reaction. Total hydrolysis of olive oil by thePythium lipase was compared with that by lipases fromCandida rugosa andRhizopus arrhizus in the invert emulsion. Hydrolysis essentially ceased within 24 h or less for the lipases from each source. However, the addition of aqueous solution at 8 h from the beginning of incubation stimulated hydrolysis byC. rugosa andR. arrhizus lipases by 1.8‐fold and 2.5‐fold, respectively, but not by theP. ultimum lipase, over corresponding controls after 48 h.
Factors affecting the acyltransfer activity of the lipase fromCandida parapsilosis in aqueous media
Authors: Briand Delphine , Dubreucq Eric , Galzy Pierre
Published: January 2007

This study describes the influence of various factors on the hydrolysis and alcoholysis activities of the lipase fromCandida parapsilosis (Ashford), Langeron and Talice in aqueous media. Optimal activities were obtained at 45°C and pH 6–6.5. The influence of the nature of the substrate on the temperature activity profiles was observed. Total or partial recovery of the activities was obtained when methanol was added to the enzyme extract after thermal denaturation. A tyrosin residue appeared to be necessary for lipase function. Magnesium was a required metal cofactor. These activities were optimal in the presence of high amounts of water (water activity >0.9).
Transesterification of soy lecithin by lipase and phospholipase
Authors: Aura Anna‐Marja , Forssell Pirkko , Mustranta Annikka , Poutanen Kaisa
Published: January 2007

Soy lecithin was modified by enzymatic transesterification in a solvent‐free system. 1,3‐SpecificRhizomucor miehei lipase was found to be efficient in the transesterification with lauric acid and oleic acid, where oleic acid was more incorporated into soy lecithin. Phospholipase A2 incorporated lauric acid hardly at all, but it hydrolyzed lecithin efficiently. The mixture of lipase and phospholipase A2 (1:1, w/w) incorporated lauric acid to the same extent as did 1,3‐specific lipase alone at the same total enzyme concentration. The main fatty acids replaced were palmitic and linoleic acids by 1,3‐specific lipase and its mixture with phospholipase A2, and linoleic and linolenic acids by phospholipase A2 alone, suggesting an improved oxidative stability of the resulting product. Hydrolysis could not be prevented, but it could be regulated by incubation time and by enzyme dosage. The minimal water content for significant incorporation of lauric acid into lecithin was below 0.5% of the weight of the reaction mixture.
α‐Tocopherol prooxidant effect and malondialdehyde production
Authors: Husain S. Rafat , Cillard J. , Cillard P.
Published: January 2007

α‐Tocopherol at high concentration (1.25×10−4M) exhibited a prooxidant effect during autoxidation of linolenic and arachidonic acids. This prooxidant activity involved a significant increase of the conjugated diene level, especially with linolenic acid. High performance liquid chromatographic evaluation of malondialdehyde, a by‐product of the hydroperoxides of polyunsaturated fatty acids, showed that malondialdehyde was not increased during prooxidant effect ofα‐tocopherol. Thus, malondialdehyde does not seem to be a good indicator for the manifestation of the prooxidant activity ofα‐tocopherol.
Destabilization and fat crystallization of whippable emulsions (toppings) studied by pulsed NMR
Authors: Barfod N. M. , Krog N.
Published: January 2007

The role of lipid surfactants in toppings has been investigated. Based on low‐resolution pNMR analysis it seems that part of the fat phase in toppings is present in a supercooled state induced by lipid‐protein interactions. Upon reconstitution in cold water, protein is desorbed from the fat globule surface and dissolves into the water, thereby eliminating the protein‐induced supercooling of the fat. Subsequently, spontaneous fat crystallization takes place which can be followed by pNMR measurements. These phenomena result in an increase in the viscosity of the reconstituted emulsion. The surfactants usually used in toppings (e.g. propylene glycol monostearate) act as destabilizing factors in the reconstituted topping emulsion, accelerating (i) protein desorption from the fat globule surface, and (ii) the crystallization rate of coalesced fat. The fat crystallization process seems to be important for the texture and foam stability of whipped toppings.
Cholesterol autoxidation‐current status
Authors: Maerker G.
Published: January 2007

Several oxidation products of cholesterol have been reported to have biological activity in animals. Cholesterol oxidizes readily in solution, in aqueous dispersion and in foods when it is exposed to air, elevated temperatures, free radical initiators, light, or a combination of these. The main outline of the pathway for cholesterol oxidation is fairly well understood and involves initial formation of allylic hydroperoxides. HPLC and GC techniques are available for measuring the concentration of cholesterol oxides in animal‐derived lipids. Biologically active cholesterol oxides have been reported to be present in egg products, dairy products, frying oils and other foods. Their concentration may be subject to process control.
Analysis of the oil extraction process in soybeans: A new continuous procedure
Authors: Wiese Kurt L. , Snyder Harry E.
Published: January 2007

Soybean oil extraction techniques were studied in which solvent was recirculated or pumped once through a suspension of soybean tissue. Both refractive index and ultraviolet absorbance were used to monitor the extraction continuously. Slices of soybean tissue showed rapid extraction from damaged tissue, followed by slow extraction from intact tissue. When soybean flakes were extracted, a continuously decreasing rate was noted. When solvent was forced through flakes, extraction was more rapid than when solvent was allowed to diffuse in and out of flakes. Reextraction of partially defatted flakes showed that the last soybean oil to be extracted was not inherently resistant to extraction. The adsorption of soybean oil to defatted flakes may account for slow removal of small quantities of oil at the end of the extraction.
Iron therapy for renal anemia: how much needed, how much harmful?
Authors: Hörl Walter H.
Published: January 2007

Iron deficiency is the most common cause of hyporesponsiveness to erythropoiesis-stimulating agents (ESAs) in end-stage renal disease (ESRD) patients. Iron deficiency can easily be corrected by intravenous iron administration, which is more effective than oral iron supplementation, at least in adult patients with chronic kidney disease (CKD). Iron status can be monitored by different parameters such as ferritin, transferrin saturation, percentage of hypochromic red blood cells, and/or the reticulocyte hemoglobin content, but an increased erythropoietic response to iron supplementation is the most widely accepted reference standard of iron-deficient erythropoiesis. Parenteral iron therapy is not without acute and chronic adverse events. While provocative animal and in vitro studies suggest induction of inflammation, oxidative stress, and kidney damage by available parenteral iron preparations, several recent clinical studies showed the opposite effects as long as intravenous iron was adequately dosed. Thus, within the recommended international guidelines, parenteral iron administration is safe. Intravenous iron therapy should be withheld during acute infection but not during inflammation. The integration of ESA and intravenous iron therapy into anemia management allowed attainment of target hemoglobin values in the majority of pediatric and adult CKD and ESRD patients.
Bone and joint alterations in acromegaly
Authors: Morselli L. L. , Manetti L. , Cosci C. , Sardella C. , Bogazzi F. , Faldini C. , Martino E. , Gasperi M.
Published: January 2007

Growth hormone (GH) is fundamental for the maintenance of bone mass and metabolism both during childhood and in adulthood. This effect is due to a complex interaction between circulating GH and IGF-I produced peripherally. In vitro data and experimental animal models have clarified many of the regulatory mechanisms underlying the characteristic skeletal changes occurring in acromegaly. This review focuses on the effects of GH excess on bone metabolism and mass in acromegalic patients and, in particular, on the influence of factors such as hypogonadism, gender, age and therapy on bone metabolism and arthropathy.
Beyond the epithelium: Cadherin function in fibrous connective tissues
Authors: El Sayegh T.Y. , Kapus A. , McCulloch C.A.
Published: January 2007

In fibrous connective tissues, fibroblasts are organized into syncytia, cellular networks that enable matrix remodeling and that are interconnected by intercellular adherens junctions (AJs). The AJs of fibroblasts are mediated by N‐cadherin, a broadly expressed classical cadherin that is critically involved in developmental processes, wound healing and several diseases of mesenchymal tissues. In contrast to E‐cadherin‐dependent junctions of epithelia, the formation of AJs in fibrous connective tissues is relatively uncharacterized. Work over the last several years has documented an expanding list of molecules which function to regulate N‐cadherin mediated junctions such as: Fer, PTP1B, cortactin, calcium, gelsolin, PIP5KIγ, PIP2, and the Rho family of GTPases. We present an overview on the regulation of N‐cadherin‐mediated junction formation that highlights recent molecular advances in the field and rationalizes the roles of N‐cadherin in connective tissue function.
Sacred Camp: Transgendering Faith in a Philippine Festival
Authors: Alcedo Patrick
Published: January 2007

By embodying the paradoxes found in three webs of signification – panaad (devotional promise), sacred camp and carnivalesque during the Ati-atihan festival – Augusto Diangson, an individual of the ‘third sex’, was able to claim membership in the Roman Catholic community of Kalibo, Aklan in the Central Philippines while also negotiating the Church's institution of heterosexuality. The narratives of mischief and the gender ambiguity of the Santo Niño or the Holy Child Jesus, the centre of Ati-atihan's religious veneration, further enabled Diangson to interact with Kalibo's Roman Catholicism. Through an analysis of Diangson and his participation in the festival, this article exposes how ordinary individuals in extraordinary events localise their faith through cross-dressing and dance performance. Seen throughout the Philippines, these processes of mimicry and gender transformation transport individuals into zones of ambivalence and contradictions in which they are able to navigate through the homogenising discourse of their culture and the Church's homogenising myth of Roman Catholicism.
Descriptions of Female Sexuality in Ayu Utami's Saman
Authors: Marching Soe Tjen
Published: January 2007

Ayu Utami's Saman, published in May 1998, describes female sexuality openly, a factor which has caused some controversy in Indonesia. Several critics have applauded the explicit descriptions of sexuality in this novel, claiming they are a means of ‘talking back’ and/or challenging patriarchal authorities in Indonesia. In contrast, some senior and well-known Indonesian writers have alleged that the novel is an example of the increasing Westernisation of their culture. The contemporary debate regarding depictions of sexuality in Saman, however, has failed to appreciate the complex post-colonial situation of the novel.
The rules and the reality of mountain gorilla Gorilla beringei beringei tracking: how close do tourists get?
Authors: Sandbrook Chris , Semple Stuart
Published: January 2007

Mountain gorilla Gorilla beringei beringei tracking tourism generates important revenue for conservation efforts but brings with it the threat of disease transmission into the gorilla population. This study quantifies for the first time aspects of encounters between gorillas and tourists at Bwindi Impenetrable National Park that are likely to contribute to the risk of disease transmission. These include how close tourists get to gorillas, how close encounters are initiated, how long they last, and the age class of gorillas involved. Tourists got significantly closer to gorillas than the park rules allow (a mean of 2.76 m, compared to the rule of 7 m), and remained close for long periods. Contacts with the gorillas most vulnerable to disease, the juveniles, were closer but of shorter duration than those with adults. Contacts initiated by gorillas were closer but shorter than those initiated by tourists. Taken together these results demonstrate that the present rules are failing, and that the risk of disease transmission may be greater than previously believed.
Methyl halide emissions from greenhouse‐grown mangroves
Authors: Manley Steven L. , Wang Nun‐Yii , Walser Maggie L. , Cicerone Ralph J.
Published: January 2007

Two mangrove species, Avicennia germinans and Rhizophora mangle, were greenhouse grown for nearly 1.5 years from saplings. A single individual of each species was monitored for the emission of methyl halides from aerial tissue. During the first 240 days, salinity was incrementally increased with the addition of seawater, and was maintained between 18 and 28‰ for the duration of the study. Exponential growth occurred after 180 days. Methyl halide emissions normalized to leaf area were measured throughout the study and varied dramatically. Emission rates normalized to land area (mg m−2 y−1), assuming a LAI = 5, yielded 82 and 29 for CH3Cl, 10 and 1.6 for CH3Br, and 26 and 11 for CH3I, for A. germinans and R. mangle, respectively. From these preliminary determinations, only CH3I emissions emerge as being of possible global atmospheric significance. This study emphasizes the need for field studies of methyl halide emissions from mangrove forests.
Experimental investigation of liquid spall in laser shock-loaded tin
Authors: de Rességuier T. , Signor L. , Dragon A. , Boustie M. , Roy G. , Llorca F.
Published: January 2007

When a metal is shocked above its melting pressure or melted on release, the tensile stresses generated upon reflection of the compressive pulse from a free surface are induced into a liquid state. Instead of the well-known spallation process observed in solid targets, cavitation is expected in the melted material, and liquid fragments are ejected from the free surface. Their size, velocity, and temperature distributions are issues of increasing interest, as well as their impact on other nearby materials, but data are limited on the subject. Here, we present an experimental study performed on tin samples subjected to high pressure laser shocks (ranging from about 50to200GPa) of short duration (∼5ns). The results include post-test observations of the ejecta recovered after impact on a polycarbonate shield and time-resolved measurements of the free surface velocity through the shield. For shock pressures below some 80GPa, the velocity profiles are compared to the predictions of one-dimensional simulations involving a multiphase equation of state. For higher loading pressures, the emergence of the shock at the free surface produces a rapid loss of reflectivity so the particle velocity cannot be determined. In all cases, solidified fragments of tin are recovered on the shield. Their sizes, their shapes, and the induced damage depend significantly on shock pressure, and are indicative of a very wide range of ejection velocities. The data provide a basis for a phenomenological description of the process.
Differences in the reaction kinetics and contact formation mechanisms of annealed Ti∕Al∕Mo∕Au Ohmic contacts on n-GaN and AlGaN∕GaN epilayers
Authors: Wang Liang , Mohammed Fitih M. , Adesida Ilesanmi
Published: January 2007

Ti ∕ Al -based multilayer metallizations are usually used interchangeably for n-GaN and AlGaN∕GaN epilayers. Our investigations show that, although excellent Ohmic performances were obtained on both cases, the reaction pathways/kinetics and Ohmic contact formation mechanisms of Ti∕Al∕Mo∕Au metallization on n-GaN and AlGaN∕GaN are different. In the case of n-GaN, the reaction proceeds by the formation of continuous TiN layer at the metal/GaN interface. Low-barrier Schottky contact or tunneling contact is the possible contact formation mechanisms. On AlGaN∕GaN heterostructures, the existence of the AlGaN layer significantly modifies the reaction pathway, where discrete TiN protrusions form nonuniformly along threading dislocations. The TiN protrusions penetrate through the AlGaN layer and form direct electrical link between the two-dimensional electron gas and the metal contacts which would otherwise be separated by the AlGaN barrier layer. A contact formation mechanism, similar to the “spike mechanism,” which dominates the Ohmic contact formation in GaAs- and InP-based devices, is proposed for the carrier transport in the case of Ti∕Al∕Mo∕Au contacts on AlGaN∕GaN. Kinetically, the formation rate of TiN is lower on AlGaN layer than on n-GaN, a result that is rationalized by the formation enthalpies of different nitrides.
Transparent ZnO thin film transistor fabricated by sol-gel and chemical bath deposition combination method
Authors: Cheng Hua-Chi , Chen Chia-Fu , Tsay Chien-Yie
Published: January 2007

Top-gate thin film transistors with n-type ZnO active channel were performed under 230°C. Especially, ZnO film was deposited by a combined method of sol-gel and chemical bath deposition without any preactivation for film growth. Silicon nitride and indium tin oxide were used as the gate insulator and the conducting electrodes (source, drain, and gate). These transistors were highly transparent in the visible spectrum, with transmittance as high as 75% to approximately 85% at wavelength from 500to700nm. The optimum device has field-effect mobility of 0.67cm2∕Vs and an on-off ratio more than 107.
Combinatorial screening of the effect of temperature on the microstructure and mobility of a high performance polythiophene semiconductor
Authors: Lucas Leah A. , DeLongchamp Dean M. , Vogel Brandon M. , Lin Eric K. , Fasolka Michael J. , Fischer Daniel A. , McCulloch Iain , Heeney Martin , Jabbour Ghassan E.
Published: January 2007

Using a gradient combinatorial approach, the authors report the effects of temperature on the microstructure and hole mobility of poly(2,5-bis(3-dodecylthiophen-2yl)thieno[3,2-b]thiophene) thin films for application in organic field-effect transistors. The gradient heating revealed a detailed dependence on thermal history. Optimal heat treatment achieved mobilities as high as 0.3cm2V−1s−1. Mobility enhancement coincides with an increase in crystal domain size and orientation, all of which occur abruptly at a temperature closely corresponding to a bulk liquid crystal phase transition.
Canonical coset parametrization and the Bures metric of the three-level quantum systems
Authors: Akhtarshenas S. J.
Published: January 2007

An explicit parametrization for the state space of an n-level density matrix is given. The parametrization is based on the canonical coset decomposition of unitary matrices. We also compute, explicitly, the Bures metric tensor over the state space of two- and three-level quantum systems.
Thickness effects on photoinduced current in ferroelectric (Pb0.97La0.03)(Zr0.52Ti0.48)O3 thin films
Authors: Qin Meng , Yao Kui , Liang Yung C. , Shannigrahi Santiranjan
Published: January 2007

Ferroelectric (Pb0.97,La0.03)(Zr0.52,Ti0.48)O3 thin films in different thicknesses were fabricated on Pt∕Ti∕SiO2∕Si substrates through a sol-gel process. Film thickness dependence of photoinduced current was investigated under the illumination of ultraviolet light. A theoretical model was developed to describe the thickness-dependent photocurrent. Both the theoretical model and experimental results showed that the photocurrent increases exponentially with the decrease in film thickness. However, photocurrent may drop in the films with the very small thickness of tens of nanometers and below in which the small size effect of ferroelectricity is considered. This model also reveals the relationship between the photocurrent and the internal electric field or remnant polarization and predicts a small diffusion current in the opposite direction at very low field or polarization region. These results provide useful guides for the design of ferroelectric film photovoltaic devices.