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Tadahiro Nagata - One of the best experts on this subject based on the ideXlab platform.
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cis trans isomerisation of Triolein trilinolein and trilinolenin induced by heat treatment
Food Chemistry, 2008Co-Authors: Wakako Tsuzuki, Reiko Nagata, Ritsuko Yunoki, Mitsutoshi Nakajima, Tadahiro NagataAbstract:Abstract To estimate the trans -fatty acid production of edible oils during the frying process, 1.0 g of Triolein, trilinolein and trilinolenin, as representative oils, were heated at 180 °C for a defined period. The amounts of trans -fatty acids in heated triacylglycerols were quantitatively determined by gas chromatography after methylation. It was revealed that heating induced cis to trans -isomerisation of unsaturated triacylglycerols, and that trans -fatty acid amounts increased gradually, depending on the heating period. For example, trans -isomer amounts in Triolein, trilinolein and trilinolenin (per gram) were 5.8 mg, 3.1 mg and 6.5 mg, respectively, after 8 h incubation at 180 °C. At that time, the contents of polar compounds contained in the heated Triolein, trilinolein and trilinolenin were 22%, 27% and 31%, respectively. When Triolein was heated under a N 2 stream, neither trans -isomerisation nor polar compounds were detected. The addition of α-tocopherol (1.0%) to Triolein significantly prevented not only lipid oxidation but also trans -isomerisation during heating. A commercially available vegetable oil was also heated under the same conditions as these model oils. Compared with the trans -isomerisation in model oils, the degree of trans -isomerisation in the edible oil was relatively low. Tocopherols in the oil would prevent not only lipid oxidation but also isomerisation. These results suggest that the geometric isomerisation of unsaturated fatty acids during heating accompanies lipid oxidation.
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cis/trans-Isomerisation of Triolein, trilinolein and trilinolenin induced by heat treatment
Food Chemistry, 2008Co-Authors: Wakako Tsuzuki, Reiko Nagata, Ritsuko Yunoki, Mitsutoshi Nakajima, Tadahiro NagataAbstract:Abstract To estimate the trans -fatty acid production of edible oils during the frying process, 1.0 g of Triolein, trilinolein and trilinolenin, as representative oils, were heated at 180 °C for a defined period. The amounts of trans -fatty acids in heated triacylglycerols were quantitatively determined by gas chromatography after methylation. It was revealed that heating induced cis to trans -isomerisation of unsaturated triacylglycerols, and that trans -fatty acid amounts increased gradually, depending on the heating period. For example, trans -isomer amounts in Triolein, trilinolein and trilinolenin (per gram) were 5.8 mg, 3.1 mg and 6.5 mg, respectively, after 8 h incubation at 180 °C. At that time, the contents of polar compounds contained in the heated Triolein, trilinolein and trilinolenin were 22%, 27% and 31%, respectively. When Triolein was heated under a N 2 stream, neither trans -isomerisation nor polar compounds were detected. The addition of α-tocopherol (1.0%) to Triolein significantly prevented not only lipid oxidation but also trans -isomerisation during heating. A commercially available vegetable oil was also heated under the same conditions as these model oils. Compared with the trans -isomerisation in model oils, the degree of trans -isomerisation in the edible oil was relatively low. Tocopherols in the oil would prevent not only lipid oxidation but also isomerisation. These results suggest that the geometric isomerisation of unsaturated fatty acids during heating accompanies lipid oxidation.
Wakako Tsuzuki - One of the best experts on this subject based on the ideXlab platform.
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cis trans isomerisation of Triolein trilinolein and trilinolenin induced by heat treatment
Food Chemistry, 2008Co-Authors: Wakako Tsuzuki, Reiko Nagata, Ritsuko Yunoki, Mitsutoshi Nakajima, Tadahiro NagataAbstract:Abstract To estimate the trans -fatty acid production of edible oils during the frying process, 1.0 g of Triolein, trilinolein and trilinolenin, as representative oils, were heated at 180 °C for a defined period. The amounts of trans -fatty acids in heated triacylglycerols were quantitatively determined by gas chromatography after methylation. It was revealed that heating induced cis to trans -isomerisation of unsaturated triacylglycerols, and that trans -fatty acid amounts increased gradually, depending on the heating period. For example, trans -isomer amounts in Triolein, trilinolein and trilinolenin (per gram) were 5.8 mg, 3.1 mg and 6.5 mg, respectively, after 8 h incubation at 180 °C. At that time, the contents of polar compounds contained in the heated Triolein, trilinolein and trilinolenin were 22%, 27% and 31%, respectively. When Triolein was heated under a N 2 stream, neither trans -isomerisation nor polar compounds were detected. The addition of α-tocopherol (1.0%) to Triolein significantly prevented not only lipid oxidation but also trans -isomerisation during heating. A commercially available vegetable oil was also heated under the same conditions as these model oils. Compared with the trans -isomerisation in model oils, the degree of trans -isomerisation in the edible oil was relatively low. Tocopherols in the oil would prevent not only lipid oxidation but also isomerisation. These results suggest that the geometric isomerisation of unsaturated fatty acids during heating accompanies lipid oxidation.
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cis/trans-Isomerisation of Triolein, trilinolein and trilinolenin induced by heat treatment
Food Chemistry, 2008Co-Authors: Wakako Tsuzuki, Reiko Nagata, Ritsuko Yunoki, Mitsutoshi Nakajima, Tadahiro NagataAbstract:Abstract To estimate the trans -fatty acid production of edible oils during the frying process, 1.0 g of Triolein, trilinolein and trilinolenin, as representative oils, were heated at 180 °C for a defined period. The amounts of trans -fatty acids in heated triacylglycerols were quantitatively determined by gas chromatography after methylation. It was revealed that heating induced cis to trans -isomerisation of unsaturated triacylglycerols, and that trans -fatty acid amounts increased gradually, depending on the heating period. For example, trans -isomer amounts in Triolein, trilinolein and trilinolenin (per gram) were 5.8 mg, 3.1 mg and 6.5 mg, respectively, after 8 h incubation at 180 °C. At that time, the contents of polar compounds contained in the heated Triolein, trilinolein and trilinolenin were 22%, 27% and 31%, respectively. When Triolein was heated under a N 2 stream, neither trans -isomerisation nor polar compounds were detected. The addition of α-tocopherol (1.0%) to Triolein significantly prevented not only lipid oxidation but also trans -isomerisation during heating. A commercially available vegetable oil was also heated under the same conditions as these model oils. Compared with the trans -isomerisation in model oils, the degree of trans -isomerisation in the edible oil was relatively low. Tocopherols in the oil would prevent not only lipid oxidation but also isomerisation. These results suggest that the geometric isomerisation of unsaturated fatty acids during heating accompanies lipid oxidation.
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Acidolysis between Triolein and short-chain fatty acid by lipase in organic solvents.
Bioscience biotechnology and biochemistry, 2005Co-Authors: Wakako TsuzukiAbstract:Ten kinds of lipases were examined as biocatalysts for the incorporation of short-chain fatty acids (acetic, propionic, and butyric acids) into Triolein in order to produce one kind of reduced-calorie structured lipids. Trans-esterification (acidolysis) was successfully done in n-hexane by several microbial lipases. Among them, lipase from Aspergillus oryzae was used to investigate the effects of incubation time, substrate molar ratio, and water content on acidolysis. Finally, more than 80% of Triolein was incorporated by butyric acid (molar ratio of Triolein to butyric acid, 1:10) in the dried n-hexane at 52 °C for 72 h. More than 90% of the products was monosubstituent, which was esterified with this short chain fatty acid at the 1-position of the glycerol moiety of Triolein. These results suggest that A. oryzae lipase would be a powerful biocatalyst for the synthesis of low caloric oil, such as triacylglycerol containing a mixture of long- and short-chain aliphatic acids.
Zijian Wang - One of the best experts on this subject based on the ideXlab platform.
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Removal of persistent organic pollutants from micro-polluted drinking water by Triolein embedded absorbent.
Bioresource technology, 2009Co-Authors: Huijuan Liu, Ruihua Dai, Zijian WangAbstract:A new biomimetic absorbent, cellulose acetate (CA) embedded with Triolein (CA-Triolein), was prepared and applied for the removal of persistent organic pollutants (POPs) from micro-polluted aqueous solution. The comparison of CA-Triolein, CA and granular activated carbon (GAC) for dieldrin removal was investigated. Results showed that CA-Triolein absorbent gave a lowest residual concentration after 24 h although GAC had high removal rate in the first 4 h adsorption. Then the removal efficiency of mixed POPs (e.g. aldrin, dieldrin, endrin and heptachlor epoxide), absorption isotherm, absorbent regeneration and initial column experiments of CA-Triolein were studied in detail. The linear absorption isotherm and the independent absorption in binary isotherm indicated that the selected POPs are mainly absorbed onto CA-Triolein absorbent by a partition mechanism. The absorption constant, K, was closely related to the hydrophobic property of the compound. Thermodynamic calculations showed that the absorption was spontaneous, with a high affinity and the absorption was an endothermic reaction. Rinsing with hexane the CA-Triolein absorbent can be regenerated after absorption of POPs. No significant decrease in the dieldrin removal efficiency was observed even when the absorption-regeneration process was repeated for five times. The results of initial column experiments showed that the CA-Triolein absorbent did not reach the breakthrough point at a breakthrough empty-bed volume (BV) of 3200 when the influent concentration was 1-1.5 microg/L and the empty-bed contact time (EBCT) was 20 min.
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Accumulation of organochlorine pesticides from water using Triolein embedded cellulose acetate membranes.
Environmental science & technology, 2005Co-Authors: Zijian Wang, Shahamat U. KhanAbstract:A new type of composite membrane, Triolein embedded cellulose acetate membrane (TECAM), was produced by embedding Triolein drops in the matrix of cellulose acetate polymers. The distribution of six organochlorine pesticides (OCPs) between water and TECAM was investigated in a static water system. Its field application was tested in Taihu Lake (China). Results from both laboratory and field experiments indicate that TECAM quickly and efficiently accumulated hydrophobic OCPs from water. Under laboratory conditions, uptake equilibrium was achieved within 24 h for all of the six OCPs. Significant correlations were obtained between log Kp TECAM (TECAM−water partition coefficient) and log Kow (octanol−water partition coefficient); between log Ktw (Triolein−water partition coefficient, Triolein in TECAM) and log Kow; and between log Ktw and log BCF (bioconcentration factor in rainbow trout calculated from literatures). Triolein in TECAM significantly increased the accumulation of strongly hydrophobic OCPs when c...
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Preparation and characteristic of Triolein-embedded composite sorbents for water purification
Separation and Purification Technology, 2005Co-Authors: Jin-xian Huo, Huijuan Liu, Zijian Wang, Haining LiuAbstract:Abstract The novel Triolein-embedded composite sorbents for removing persistent organic pollutants (POPs) in water were developed. Comprehensive structural characteristics of the composite sorbents were characterized using scanning electron microscope (SEM), fourier transform infrared spectrum (FT-IR) and X-ray photoelectron spectrum (XPS). It is suggested that Triolein/cellulose acetate (CA) viscous syrup can be deposited on the surface of silica gel granules, because the silica gel granules have the large enough aperture to make the polymer penetrate into. Triolein is also embedded into a hybrid membrane perfectly. Dieldrin is regarded as a representative compound of POPs. Sorption experiments in solutions with constant concentrations show that adsorption capacity increased with increased Triolein content in composite adorbents. Dieldrin removal could reach 80% at 50 ng/l initial concentration, which is near the environmental level.
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Accumulation of organochlorinated pesticides by Triolein-containing semipermeable membrane device (Triolein-SPMD) and rainbow trout.
Water research, 2003Co-Authors: Zijian WangAbstract:An important advance in aquatic ecotoxicology is the development and application of biomimetic sampling technology for hydrophobic contaminants. In this paper, accumulation kinetics of five organochlorinated pesticides, i.e. hexachlorobenzene, lindan, aldrin, heptachlor epoxide and 4,4'-DDT, by Triolein-containing semipermeable membrane device (Triolein-SPMD) and by fish (rainbow trout) were compared in a laboratory continuous flow system. Accumulation kinetics of organochlorinated pesticides by the Triolein-SPMD and by rainbow trout were linear during the exposure period of 20 d, except for lindan. Approach of an asymptote could be observed for lindan at the end of the exposure for rainbow trout. When the kinetic data were used to calculate the first-order uptake rate constants, it was found that the uptake rates of the chemicals in Triolein-SPMD were 1-2.5 times higher than those in the fish. The estimated bioconcentration factors of the five pesticides in rainbow trout were in the range of 1000-7000 and the device concentration factor in the range of 1500-18000. Although equilibrium was not reached for most pesticides under 21-d exposure period, correlations between C-L/C-w and K-ow (R-2 = 0.887) and C-f/C-w and K-ow (R-2 = 0.931) could be observed which was a clear indication that Triolein-SPMD accumulates chlorinated pesticides in a quite similar way as fish do. Our results show that Triolein-SPMD could serve as a good surrogate for rainbow trout for simulating accumulations of chlorinated pesticides and may be used as a universal surrogate for fish in natural waters. (C) 2003 Elsevier Science Ltd. All rights reserved.
T. Rannem - One of the best experts on this subject based on the ideXlab platform.
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The [14C]-Triolein breath test is not valid as a test of fat absorption.
Scandinavian journal of clinical and laboratory investigation, 1991Co-Authors: N. T. Pedersen, B. Bang Jørgensen, T. RannemAbstract:The [14C]-Triolein breath test is used as a test of fat absorption. However, its validity has not been established. The aim of this study was to investigate, whether the absorption of [14C]-Triolein could be estimated from the breath test, and whether the breath test could be useful as a clinical test. The [14C]-Triolein absorption was estimated from faecal measurements, using 5lCrCl3 as nonabsorbable marker. The breath test was done according to the standard technique with hourly estimations of the l4C02 expiration. Fifty-one patients participated. A nearly perpendicular, curvilinear relation between the 6-h cumulative 14CO2 expiration and the [14C]-Triolein absorption was found, and no obvious cut-off level for normal 14CO2 expiration could be identified. Accordingly, the diagnostic sensitivity of the breath test was 80% at the expense of a specificity of 45%. In 19 patients duplicate measurements were done. A high intra- and inter-individual variation in the fraction of absorbed [l4C]-Triolein, expired...
Clarence A. Miller - One of the best experts on this subject based on the ideXlab platform.
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solubilisation of Triolein by microemulsions containing c12e4 hexadecane water equilibrium and dynamics
Journal of Colloid and Interface Science, 2008Co-Authors: Peter Robert Garrett, Clarence A. Miller, Denise Carr, Dennis Giles, Edward Staples, Gina Pierrelouis, Bing Hung ChenAbstract:Abstract Increasing Triolein content of oil-in-water microemulsions in the pure C12E4/water/n-hexadecane/Triolein system while maintaining a fixed surfactant concentration and volume fraction of drops raises the temperature of the solubilisation boundary, where excess oil separates, but has only a slight effect on the (higher) cloud point temperature, where excess water appears. Thus, the temperature range of the single-phase microemulsion shrinks and ultimately disappears. When such microemulsions are in equilibrium with excess oil, the hexadecane/Triolein ratio is greater in the microemulsion, probably because the larger Triolein molecules are unable to penetrate the hydrocarbon chain region of the surfactant films of the microemulsion droplets. Indeed, monolayer studies and calculations based on microemulsion and excess oil compositions indicate that the films have minimal Triolein and similar ratios of hexadecane to surfactant. Triolein drops brought into contact with hexadecane-in-water microemulsions first swell as they incorporate hexadecane, then shrink owing to solubilisation. Interfacial tension decreases during this process until it becomes almost constant near 0.01 mN m−1, suggesting that the drops in the final stages of solubilisation have high hexadecane contents. A microemulsion containing 10 wt% C12E4 and 15 wt% hexadecane was able to remove over 50% of Triolein from polyester fabric at 25 °C, more than twice that removed by an oil-free solution with the same surfactant concentration in similar experiments.
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Solubilisation of Triolein by microemulsions containing C12E4/hexadecane/water: equilibrium and dynamics.
Journal of colloid and interface science, 2008Co-Authors: Peter Robert Garrett, Clarence A. Miller, Denise Carr, Dennis Giles, Gina Pierre-louis, Edward Staples, Bing Hung ChenAbstract:Abstract Increasing Triolein content of oil-in-water microemulsions in the pure C12E4/water/n-hexadecane/Triolein system while maintaining a fixed surfactant concentration and volume fraction of drops raises the temperature of the solubilisation boundary, where excess oil separates, but has only a slight effect on the (higher) cloud point temperature, where excess water appears. Thus, the temperature range of the single-phase microemulsion shrinks and ultimately disappears. When such microemulsions are in equilibrium with excess oil, the hexadecane/Triolein ratio is greater in the microemulsion, probably because the larger Triolein molecules are unable to penetrate the hydrocarbon chain region of the surfactant films of the microemulsion droplets. Indeed, monolayer studies and calculations based on microemulsion and excess oil compositions indicate that the films have minimal Triolein and similar ratios of hexadecane to surfactant. Triolein drops brought into contact with hexadecane-in-water microemulsions first swell as they incorporate hexadecane, then shrink owing to solubilisation. Interfacial tension decreases during this process until it becomes almost constant near 0.01 mN m−1, suggesting that the drops in the final stages of solubilisation have high hexadecane contents. A microemulsion containing 10 wt% C12E4 and 15 wt% hexadecane was able to remove over 50% of Triolein from polyester fabric at 25 °C, more than twice that removed by an oil-free solution with the same surfactant concentration in similar experiments.
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Rates of Solubilization of Triolein/Fatty Acid Mixtures by Nonionic Surfactant Solutions
Langmuir, 1998Co-Authors: Bing Hung Chen, Clarence A. Miller, Peter Robert GarrettAbstract:Spontaneously-generated convection and rapid initial solubilization were observed when drops containing mixtures of Triolein and oleic acid were injected into aqueous solutions of nonionic surfactants. For drops having oleic acid contents between 15% and 25% by weight, solubilization rates were at least an order of magnitude greater than those found for pure Triolein, and drop volumes decreased by amounts ranging from 45% to 70% in less than 5 min with no external stirring. With the assumption that the end of the rapid solubilization period occurred because most of the oleic acid had been solubilized, it could be shown that about two thirds by volume of the material solubilized was Triolein. At later times the solubilization rate was about the same as that for pure Triolein with the same surfactant solutions. A similar effect was observed during the first minute or two after contact for a hydrocarbon/oleic acid mixture. Spontaneously-generated convection and rapid initial solubilization of Triolein occurr...
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Equilibrium and dynamic behavior for systems containing nonionic surfactants, n-hexadecane, Triolein and oleyl alcohol
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 1995Co-Authors: Shehata M. Zourab, Clarence A. MillerAbstract:Abstract Phase behavior and electrical conductivity experiments were carried out for systems containing water, nonionic surfactants, Triolein, n -hexadecane and oleyl alcohol. In systems where the amount of Triolein was equal to or greater than the amount of n -hexadecane, the surfactant appeared successively in the lamellar liquid crystalline phase L α , the sponge phase D′, a bicontinuous microemulsion D and an oil-rich microemulsion O m as the system was made more lipophilic. The temperatures of the various phase transitions decreased with increasing hydrocarbon content. In one system five phases were found to coexist simultaneously: L α , D′, D, and excess water and oil. Conductivity measurements indicated no major change in microstructure of either D′ or D phases when the n -hexadecane-to-Triolein ratio was changed from zero to one. In systems where the amount of hydrocarbon was much greater than the amount of Triolein, the usual microemulsion phase behavior was seen with continuous variation of oil and water solubilization over a wide range. Videomicroscopy contacting experiments were consistent with the phase behavior results in that the D′ phase was observed as one intermediate phase when drops rich in Triolein were injected into aqueous surfactant solutions but not when the drops were mainly hydrocarbon. In the latter case, microemulsions were seen which inverted continuously until the surfactant concentration in the drops became high enough that the lamellar phase formed.
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effect of secondary alcohol ethoxylates on behavior of Triolein water surfactant systems
Journal of the American Oil Chemists' Society, 1994Co-Authors: Teeradetch Tungsubutra, Clarence A. MillerAbstract:Study of the equilibrium phase behavior of systems containing water, Triolein and secondary alcohol ethoxylates showed that a D or microemulsion phase, which solubilized significant amounts of Triolein, formed at temperatures as low as 25°C when the surfactant was a suitable mixture of TERGITOL 15-S-3 and 15-S-5 (Union Carbide, Charleston, WV) with average ethylene oxide numbers of 3 and 5, respectively. In previous work with pure C12 linear ethoxylates and Triolein, the D phase had formed only at temperatures above about 55°C. Based on the earlier studies, formation of the D phase would be expected to improve soil removal from synthetic fabrics by a solubilization-emulsification mechanism. When sufficient oleyl alcohol was mixed with Triolein, the D phase was observed at 25°C with Tergitol 15-S-5 alone. Observation of dynamic behavior in this system for Triolein-oleyl alcohol drops injected into surfactant-water mixtures revealed that intermediate phases frequently formed near the drop surfaces and that considerable spontaneous emulsification of Triolein occurred for appropriate drop compositions. Experiments with drops initially attached to individual polyester fibers confirmed that little oil remained on the fibers when emulsification was extensive. This mechanism involving spontaneous emulsification provides a means for soil removal different from that found previously in other systems, where the soil was solubilized into an intermediate phase, and this phase was emulsified by externally imposed agitation.
