- Revealing ruthenium and basicity synergetic effects in Ru-MgAl catalysts for isomerization of linoleic acid to conjugated linoleic acid
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Ru-MgAl catalysts were prepared by co-precipitation at different pH values (x = 7-12), with the aims of investigating the effect of pH on their catalytic performance for isomerization of linoleic acid to conjugated linoleic acid and of understanding the relationship of basicity site and ruthenium activity site. The results showed that strong basicity and highly dispersed ruthenium may be the active sites for linoleic acid isomerization. Only if all three conditions, i.e., high Ru dispersion, appropriate SMSI effect and high number of strong basicity sites, are fulfilled can highly effective active sites be formed for the isomerization of linoleic acid to conjugated linoleic acid. A possible reaction mechanism for the isomerization was also proposed.
- Chen, Jiebo,Zhang, Liaoyuan,Zheng, Xinyu,Zheng, Ying
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p. 54747 - 54755
(2017/12/12)
-
- Investigation of Micellization and Vesiculation of Conjugated Linoleic Acid by Means of Self-Assembling and Self-Crosslinking
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Bioactive and biocompatible conjugated linoleic acid (CLA) has been only considered as a food or medicine ingredient due to its rare natural occurrence. In this work, the surface activities and pH-induced self-assembling behaviors of the semi-synthetic CLA molecules into micelles or vesicles were systematically investigated. First, the self-assembling of CLA was studied in detail, and it was found that aside from temperature and ionic strength, pH is the prominent factor affecting the self-assembling of CLA. Moreover, stable CLA ufasomes (unsaturated fatty acid liposomes) in uniform size were obtained by self-crosslinking of the CLA ufasomes, and the morphologies of the crosslinked CLA assemblies were recorded by transmission electron microscopy, which made known the pH-induced formation of the CLA ufasomes or the CLA micelles. The crosslinked CLA assemblies presented improved properties such as a higher calcium stability, a lower lime soap dispersing requirement and a better solubilization ability than that of the CLA molecules themselves or the pre-crosslinked linoleic acids. These investigations could be helpful for comprehensively understanding effects of environment factors on self-assembling behaviors of conjugated fatty acids and responsive polymerization of polymerizable surfactants.
- Fan, Ye,Fang, Yun,Ma, Lin,Jiang, Hang
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p. 179 - 188
(2015/07/27)
-
- Synergetic effect of ruthenium and basicity sites in the Ru-MgAl catalyst for hydrogen-free production of conjugated linoleic acids
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A series of Ru-MgAl composite oxide catalysts prepared by calcining the ruthenium grafted hydrotalcite-like precursor at various temperatures were used in the hydrogen-free production of conjugated linoleic acid. The effect of calcination temperature on the textural, base and catalytic properties of the materials was investigated. Results indicated that the Ru-MgAl composite oxides calcined at 450 °C showed high activity, namely, CLA productivity, CLA production rate and TOF up to 1.52 g CLA g (CLA) L-1 (solvent) min-1, 284 g (CLA) g-1 (Ru) h-1 and 102.6 mol (LA converted) mol-1 (Ru) h-1. Moreover, the biologically active CLA isomers, cis-9, trans-11, trans-10, cis-12 and trans-9, trans-11-CLA, were the main products, while almost no hydrogenated products were formed. Meanwhile, the role of ruthenium and basicity sites in the catalytic reaction has been studied. It was found that the basicity sites of the Ru-MgAl catalyst and the ruthenium activity sites seem to have a synergic effect on the catalytic reaction. The possible reaction mechanism for the isomerization was also proposed. This journal is
- Chen, Jiebo,Chen, Xinxiang,Zheng, Ying,Li, Qinglu
-
p. 20248 - 20255
(2015/03/18)
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- Synthesis of phosphatidylcholine with conjugated linoleic acid and studies on its cytotoxic activity
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Phospholipids with conjugated linoleic acid (CLA), which are potential lipid prodrugs, were synthesised. CLA was obtained by the alkali-isomerisation of linoleic acid and was subsequently used in the synthesis of 1,2-di(conjugated)linoleoyl-sn-glycero-3-phosphocholine in good (82%) yield. 1-Palmitoyl-2-(conjugated)linoleoyl-sn-glycero-3-phosphocholine was obtained by a two-step synthesis in 87% yield. All the compounds were tested in an in vitro cytotoxicity assay against two human cancer cell lines, HL-60 and MCF-7, and a mouse fibroblast cell line, Balb/3T3. The free form of CLA exhibited the highest activity against all cancer cell lines. Results obtained for the Balb/3T3 line proved that phosphatidylcholine derivatives decreased the cytotoxic effect of CLA against healthy cell lines.
- Niezgoda, Natalia,Mitula, Pawel,Kempinska, Katarzyna,Wietrzyk, Joanna,Wawrzenczyk, Czeslaw
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p. 354 - 361
(2013/05/22)
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- Method For The Production Of Conjugated Polyunsaturated Fatty Acids With Heterogenous Catalysts
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The present invention relates to an improved process for the production of conjugated polyunsaturated fatty acids (PUFA), preferably conjugated linoleic acid (CLA), using finely dispersed heterogeneous metal catalysts on a mesoporous support, in the absence of Hg. The present invention also relates to a method to increase the large microporosity and (optionally) the small mesoporosity of a zeolite, thus obtaining a modified zeolite having a large and highly accessible internal surface.
- -
-
Paragraph 0105
(2013/09/26)
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- Sustainable and efficient methodology for CLA synthesis and identification
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Microwave-assisted organic synthesis and continuous-flow techniques have been successfully employed for the preparation of conjugated linoleic acids (CLA), compounds with high health beneficial effects. A good production rate of CLA was obtained. A sustainable methodology for the differentiation of both positional and geometrical CLA isomers (diene), based on the analysis by NMR spectroscopy of the resulting Diels-Alder cycloadducts with an appropriate dienophile, was developed.
- Moreno, Maria,Gomez, M. Victoria,Cebrian, Cristina,Prieto, Pilar,De La Hoz, Antonio,Moreno, Andres
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p. 2584 - 2594
(2013/02/23)
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- Probing lipid peroxidation by using linoleic acid and benzophenone
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A thorough mechanistic study has been performed on the reaction between benzophenone (BZP) and a series of 1,4-dienes, including 1,4-cyclohexadiene (CHD), 1,4-dihydro-2-methylbenzoic acid (MBA), 1,4-dihydro-1,2-dimethylbenzoic acid (DMBA) and linoleic acid (LA). A combination of steady-state photolysis, laser flash photolysis (LFP), and photochemically induced dynamic nuclear polarization (photo-CIDNP) have been used. Irradiation of BZP and CHD led to a cross-coupled sensitizer-diene product, together with 6, 7, and 8. With MBA and DMBA as hydrogen donors, photoproducts arising from cross-coupling of sensitizer and diene radicals were found; compound 7 was also obtained, but 6 and o-toluic acid were only isolated in the irradiation of BZP with MBA. Triplet lifetimes were determined in the absence and in the presence of several diene concentrations. All three model compounds showed similar reactivity (k q≈108 M-1 s-1) towards triplet excited BZP. Partly reversible hydrogen abstraction of the allylic hydrogen atoms of CHD, MBA, and DMBA was also detected by photo-CIDNP on different timescales. Polarizations of the diamagnetic products were in full agreement with the results derived from LFP. Finally, LA also underwent partly reversible hydrogen abstraction during photoreaction with BZP. Subsequent hydrogen transfer between primary radicals led to conjugated derivatives of LA. The unpaired electron spin population in linoleyl radical (LA.) was predominantly found on H(1-5) protons. To date, LA-related radicals were only reported upon hydrogen transfer from highly substituted model compounds by steady-state EPR spectroscopy. Herein, we have experimentally established the formation of LA. and shown that it converts into two dominating conjugated isomers on the millisecond timescale. Such processes are at the basis of alterations of membrane structures caused by oxidative stress. Copyright
- Andreu, Inmaculada,Neshchadin, Dmytro,Rico, Enrique,Griesser, Markus,Samadi, Abdelouahid,Morera, Isabel M.,Gescheidt, Georg,Miranda, Miguel A.
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scheme or table
p. 10089 - 10096
(2011/10/13)
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- Linoleic acid isomerization over mesoporous carbon supported gold catalysts
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Gold catalyst supported on mesoporous carbon and silica were synthesized, characterized by TEM, XRD, XPS and tested in linoleic acid isomerization. Nature of the support affects the selectivity towards isomerization in relation to unwanted hydrogenation.
- Simakova, Olga A.,Leino, Anne-Riikka,Campo, Betiana,M?ki-Arvela, P?ivi,Kordás, Krisztián,Mikkola, Jyri-Pekka,Murzin, Dmitry Yu.
-
experimental part
p. 32 - 36
(2010/11/16)
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- Superior anticarcinogenic activity of trans, trans-conjugated linoleic acid in N-methyl-N-nitrosourea-induced rat mammary tumorigenesis
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The anticarcinogenic activity of a mixture of trans,trans-conjugated linoleic acid (trans,trans-CLA) was investigated in rat mammary tumorigenesis induced by N-methyl-N-nitrosourea (MNU), with references to cis-9,trans-11-CLA and trans-10,cis-12-CLA isomers. Female, 7-week-old Sprague-Dawley rats were intraperitoneally injected with MNU (50 mg/kg of body weight) and then subjected to one of five diets (control, 1% trans,trans-CLA, 1% cis-9,trans-11-CLA, 1% trans-10,cis-12-CLA, and 1% linoleic acid; 8 rats/group) for 16 weeks. Food and water were made available ad libitum. trans,trans-CLA significantly (p 0.05) reduced tumor incidence, number, multiplicity, and size and significantly (p 0.05) increased apoptosis, relative to cis-9,trans-11-CLA and trans-10,cis-12-CLA. The molecular mechanism of trans,trans-CLA was elucidated by measuring apoptosis-related gene products and fatty acid composition in tumors. trans,trans-CLA led to increases in the p53 protein and Bax protein levels but suppressed the expression of Bcl-2 protein. The activation of caspase-3 led to the cleavage of poly(ADP-ribose) polymerase, which resulted in the execution of apoptosis. In addition, trans,trans-CLA reduced cytosolic phospholipase A2, cyclooxygenease-2, and peroxisome proliferator-activated receptor γ protein levels. These results suggest that the trans,trans-CLA inhibits MNU-induced rat mammary tumorigenesis through the induction of apoptosis in conjunction with the reduction of arachidonic acid metabolites and that the efficacy of trans,trans-CLA is superior to cis-9,trans-11-CLA and trans-10,cis-12-CLA.
- Islam, Mohammad A.,Kim, Young S.,Oh, Tae W.,Kim, Gon S.,Won, Chung K.,Kim, Hoon G.,Choi, Myung S.,Kim, Jeong O.,Ha, Yeong L.
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experimental part
p. 5670 - 5678
(2011/08/05)
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- Chemoenzymatic conversion of linoleic acid into conjugated linoleic acid
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An efficient chemoenzymatic method for preparing conjugated linoleic acid (CLA) using free linoleic acid (LA) as a substrate is described. In the first step, LA was transformed into 10-hydroxy-cis-12octadecenoic acid (HA) by the whole cells of Lactobacillus plantarum after 48 h of incubation. The preincubation of whole cells with 0.03% LA resulted in a better yield of HA (480 mg/g) compared to cells grown without LA. In a second fast microwave step, HA was converted to cis-9, trans-11-octadecadienoic acid in the presence of iodine as a catalyst over a silica gel surface. The advantage of this method in preparing cis-9,.trans-11 CLA is simple via the whole cell bioconversion of LA into HA via L plantarum followed by the fast microwave-assisted synthesis of cis-9, trans-11 CLA in higher yields.
- Demir, Ayhan S.,Talpur, Farah N.
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experimental part
p. 1646 - 1652
(2010/09/09)
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- Fatty acid desaturation and elongation reactions of trichoderma sp. 1-OH-2-3
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The fatty acid desaturation and elongation reactions catalyzed by Trichoderma sp. 1-OH-2-3 were investigated. This strain converted palmitic acid (16:0) mainly to stearic acid (18:0), and further to oleic acid (c9-18:1), linoleic acid (c9,c12-18:2), and α-linolenic acid (c9,c12,c15-18:3) through elongation, and Δ9, Δ12, and Δ15 desaturation reactions, respectively. Palmitoleic acid (c9-16:1) and cis-9,cis-12- hexadecadienoic acid were also produced from 16:0 by the strain. This strain converted n-tridecanoic acid (13:0) to cis-9-heptadecenoic acid and further to cis-9,cis-12-heptadecadienoic acid through elongation, and Δ9 and Δ12 desaturation reactions, respectively. trans-Vaccenic acid (t11-18:1) and trans-12-octadecenoic acid (t12-18:1) were desaturated by the strain through Δ9 desaturation. The products derived from t11-18:1 were identified as the conjugated linoleic acids (CLAs) of cis-9,trans-11-octadecadienoic acid and trans-9,trans-11-octadecadienoic acid. The product derived from t12-18:1 was identified as cis-9,trans-12-octadecadienoic acid. cis-6,cis-9-Octadecadienoic acid was desaturated to cis-6,cis-9,cis-12-octadecatrienoic acid by this strain through Δ12 desaturation. The broad substrate specificity of the elongation, and Δ9 and Δ12 desaturation reactions of the strain is useful for fatty acid biotransformation.
- Ando, Akinori,Ogawa, Jun,Kishino, Shigenobu,Ito, Taiyo,Shirasaka, Norifumi,Sakuradani, Eiji,Yokozeki, Kenzo,Shimizu, Sakayu
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experimental part
p. 227 - 233
(2010/06/16)
-
- Process for producing concentrate of conjugated fatty acid
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An easy and inexpensive process by which a concentrate of a given unsaturated fatty acid can be obtained from a mixture which has conventionally been difficult to concentrate. The process, which is for producing a concentrate of a desired isomer (a) from a conjugated fatty acid mixture (A), is characterized by comprising: a step in which the conjugated fatty acid mixture (A) is mixed with at least one unsaturated fatty acid (B) to obtain a mixture solution containing the isomer (a) dissolved therein; a crystallization step in which either crystals rich in the isomer (a) or crystals poor in the isomer (a) are precipitated from the mixture solution; and a solid-liquid separation step for obtaining the crystals rich in the isomer (a) or for obtaining a solution rich in the isomer (a) by removing the crystals poor in the isomer (a).
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Page/Page column 4; 5; 6
(2008/06/13)
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- Method for the preparation of conjugated linoleic acid
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Methods are disclosed for the preparation of conjugated linoleic acid from linoleic acid-containing starting material(s) by alkali isomerization in apolar solvents. According to one of the method variations, the apolar solvent is an apolar aprotic solvent and an alkali metal alcoholate is used as base. In the other method variation a long chain alcohol of 6-20 carbon atoms is used as solvent, an alkali metal hydroxide or an alkali earth metal hydroxide or an alkali metal alcoholate is used as base, and the isomerization is carried out at 100-170° C.
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Page/Page column 4-6
(2008/06/13)
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- Method for preparing unsaturated fatty acids
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Disclosed relates to a method for preparing unsaturated fatty acids and, more particularly, to a method for preparing unsaturated fatty acids in a high purity of at least 99% by isolating and purifying unsaturated fatty acids via a secondary nucleation mechanism using fatty acid-urea inclusion compounds.
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Page/Page column 3; Sheet 2
(2008/06/13)
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- Synthesis of trans-vaccenic acid and cis-9-trans-11-conjugated linoleic acid
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The preparation of the monounsaturated fatty acid, trans-vaccenic acid 4 (TVA), using both Wittig and one-pot Julia-Kocieński olefination protocol, was achieved in good yield. Similarly a Wittig approach was employed for the stereoselective synthesis of cis-9-trans-11-conjugated linoleic acid 2 from trans-2-nonenal and (8-carboxyoctyl)triphenylphosphonium bromide 12.
- Duffy, Patricia E.,Quinn, Sonia M.,Roche, Helen M.,Evans, Paul
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p. 4838 - 4843
(2007/10/03)
-
- Process
-
A process for producing a conjugated di- or poly-unsaturated fatty acid having from 12 to 24 carbon atoms, or a salt or ester thereof, comprises reacting a non-conjugated free fatty acid, or a salt or ester thereof with a base in the presence of a solvent comprising a monohydric alcohol having from 1 to 6 carbon atoms, wherein the reaction is carried out at a temperature of from 120° C. to 200° C. in the presence of water in an amount of at least 4% by weight based on alcohol.
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Page/Page column 4-5
(2008/06/13)
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- Prophylactic agent of hypertension containing a conjugated fatty acid as an effective ingredient and the use thereof
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The objects of this invention are to prevent or ameliorate hypertension to improve physical constitution and finally to provide feeds, drinks, foods, health food supplements and pharmaceuticals which may be led to the prophylaxis or amelioration of life style related diseases.A prophylactic or ameliorating agent of hypertension comprising conjugated fatty acids (e.g., conjugated linoleic acid) as effective ingredients.A feed, food and drink, and health food supplement comprising the conjugated fatty acids described above.A pharmaceutical comprising the conjugated fatty acids described above.A method for prophylactic or ameliorating of hypertension in a mammal, which comprises administering to the mammal an effective amount of a conjugated fatty acid for preventing or ameliorating of hypertension in the mammal.Use of a conjugated fatty acid for preparing a pharmaceutical for prophylactic or ameliorating of hypertension.
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-
-
- Compositions comprising reverse isomers of conjugated linoleic acid
-
The present invention relates to the field of human and animal nutrition, and in particular to certain novel compositions of conjugated linoleic acids (CLA). In particular, the present invention relates to CLA compositions comprising the c10,t12, c10,c12, t9,c11 and c9,c11 isomers of conjugated linoleic acid.
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Page/Page column 10
(2008/06/13)
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- Direct conversion of linoleic acid over silver catalysts in the presence of H2: An unusual way towards conjugated linoleic acids
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(Chemical Equation Presented) A silver lining: The isomerization of conjugated double bonds over silver catalysts in the presence of hydrogen are unusual and hitherto unknown. Silver catalysts control the selectivity of the extremely difficult isomerization of linoleic acid towards the physiologically important 9-cis,11-trans- and 10-trans, 12-cis-unsaturated isomers, which are anticarcinogenic and antiarteriosclerotic agents (see scheme, CLA = conjugated linoleic acids).
- Kreich, Markus,Claus, Peter
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p. 7800 - 7804
(2007/10/03)
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- Heterogeneous catalytic production of conjugated linoleic acid
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Kinetic experiments in selective isomerization of technical grade (~55%) linoleic acid to cis-9,trans-11-conjugated linoleic acid (B) and trans-10,cis-12-conjugated linoleic (E) acid isomers were performed batchwise at 165°C over two series of supported metal catalysts, i.e., hydrogen preactivated and nonpreactivated. Activated carbon- and aluminium oxide-supported Ru, Pd, Os, Ir, and Pt-Rh catalysts with 5 wt % metal loading were screened. Catalyst characterization was done by X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy-energy-dispersive X-ray analysis (SEM-EDX), temperature-programmed desorption of hydrogen (H2-TPD), direct current plasma atomic emission spectrometry (DCP-AES), and nitrogen adsorption techniques. Over such catalysts, the reaction scheme involves six steps: (1) double bond migration of linoleic acid to conjugated linoleic acid, (2) positional and geometric isomerization of conjugated linoleic acid, (3) double bond hydrogenation of linoleic acid to monoenoic acids, (4) double bond hydrogenation of conjugated linoleic acid to monoenoic acids, (5) positional and geometric isomerization of monoenoic acids, and (6) double bond hydrogenation of monoenoic acids to stearic acid. Over Ru/C catalyst, chemisorbed hydrogen on the metal surface dramatically increased the linoleic acid isomerization rate in a diluted system as an astoichiometric component-enhancing double bond migration but decreased the isomerization rate by promoting deactivation in a solvent-free system. Over Ru/Al2O3 catalyst, on the other hand, dissociated hydrogen increased the isomerization rate for both the diluted and nondiluted systems. The effect of eliminating the solvent was an increase of the turnover frequency (TOF) at 165°C by a factor of 12 with respect to that shown in a diluted system. At the same conversion carbon-and aluminium oxide-supported Ru catalyst showed higher selectivity toward B and E than carbon-supported Pd, Os, Ir, and Pt-Rh catalysts.
- Bernas, Andreas,Kumar, Narendra,Maeki-Arvela, Paeivi,Holmbom, Bjarne,Salmi, Tapio,Murzin, Dmitry Yu.
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p. 341 - 352
(2013/09/05)
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- NEW CONJUGATED LINOLENIC ACIDS AND METHODS FOR COMMERCIAL PREPARATION AND PURIFICATION
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A method for the preparation and purification of conjugated linolenic acids is described. The method comprises blending a mixture of vegetable oils and or fats including various concentrations of alpha or gamma and or both linolenic acids with a base. The method transforms approximately over two thirds of α-linolenic acid (9Z,12Z,15Z-octadecatrienoic acid) into 9Z,11E,15Z-octadecatrienoic acid and 9Z,13E,15Z-octadecatrienoic acid. The method also transforms gamma-linolenic acid (6Z,9Z,12Z-octadecatrienoic acid) into 6Z,8E,15Z-octadeccatrienoic acid and 6Z,10E,12Z-octadecatrienoic acid. In all cases, geometrical isomers and fully conjugated isomers are also produced.
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- Purification of conjugated linoleic acid isomers through a process including lipase-catalyzed selective esterification.
-
A mixture of conjugated linoleic acids (CLAs) was prepared by alkali conjugation of high purity linoleic acid. The preparation contained 45.1 wt% cis-9, trans-11 (c9,t11)-CLA, 46.8 wt% trans-10, cis-12 (t10,c12)-CLA, and 5.3 wt% other CLAs. A process comprising Candida rugosa lipase-catalyzed selective esterification with lauryl alcohol, molecular distillation, and urea adduct fractionation under strict conditions in ethanol was very effective for purification of c9,t11- and t10,c12-CLAs. In particular, the urea adduct fractionation efficiently eliminated CLAs except c9,t11- and t10,c12-isomers. Purification of c9,t11- and t10,c12-CLAs from 1.0 kg of the CLA mixture increased the c9,t11-CLA purity to 93.1% with 34% recovery of the initial content, and increased the t10,c12-CLA purity to 95.3% with 31% recovery.
- Nagao, Toshihiro,Yamauchi-Sato, Yoshie,Sugihara, Akio,Iwata, Toshio,Nagao, Koji,Yanagita, Teruyoshi,Adachi, Shuji,Shimada, Yuji
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p. 1429 - 1433
(2007/10/03)
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- Ricinoleic acid and castor oil as substrates for conjugated linoleic acid production by washed cells of Lactobacillus plantarum.
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Ricinoleic acid (12-hydroxy-cis-9-octadecaenoic acid) was an effective substrate for conjugated linoleic acid (CLA) production by washed cells of Lactobacillus plantarum AKU 1009a. The CLA produced was a mixture of cis-9,trans-11- and trans-9,trans-11-octadecadienoic acids. Addition of alpha-linolenic acid to the culture medium increased the CLA productivity of the washed cells. In the presence of lipase, castor oil, in which the main fatty acid component is ricinoleic acid, also was a substrate for CLA.
- Kishino, Shigenobu,Ogawa, Jun,Ando, Akinori,Omura, Yoriko,Shimizu, Sakayu
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p. 2283 - 2286
(2007/10/03)
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- A New Heterogeneously Catalytic Pathway for Isomerization of Linoleic Acid over Ru/C and Ni/H-MCM-41 Catalysts
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The isomerization reaction of linoleic acid (cis-9,cis-12-octadecadienoic acid) to conjugated linoleic acids (CLA) was studied. A new heterogeneously catalytic pathway was developed for synthesis of CLA at mild reaction conditions (80-120 deg C) over Ru/C and Ni/H-MCM-41 catalysts in a diluted system. The isomerization reaction was tested in 1-octanol and n-decane. Solvents with low polarity were selected to afford good reactant adsorption on the catalyst surface and a high solvent-to-reactant ratio was used to prevent potential side reactions. Catalyst characterization was done by X-ray powder diffraction, X-ray fluorescence, X-ray photoelectron spectroscopy, hydrogen temperature-programmed desorption, direct current plasma atomic emission spectrometry, and BET techniques. The reactions taking place were isomerization of linoleic acid C18:2, hydrogenation of C18:2 acids to C18:1 monounsaturated octadecenoic acids (oleic acid, elaidic acid, cis-vaccenic acid and trans-vaccenic acid), and further hydrogenation of C18:1 acids to C18:0 stearic acid (n-octadecanoic acid) where isomerization and hydrogenation were two competing parallel reactions. The isomerization reaction was enhanced by preactivation of the catalysts under hydrogen, but such a treatment also increased the side reaction double-bond hydrogenation.
- Bernas, Andreas,Laukkanen, Pekka,Kumar, Narendra,Maeki-Arvela, Paivi,Vayrynen, Juhani,Laine, Ensio,Holmbom, Bjarne,Salmi, Tapio,Murzin, Dmitry Yu.
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p. 354 - 366
(2007/10/03)
-
- Conjugated linoleic acid production from linoleic acid by lactic acid bacteria
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After screening 14 genera of lactic acid bacteria, Lactobacillus plantarum AKU 1009a was selected as a potential strain for CLA production from linoleic acid. Washed cells of L. plantarum with high levels of CLA production were obtained by cultivation in
- Kishino, Shigenobu,Ogawa, Jun,Omura, Yoriko,Matsumura, Kenji,Shimizu, Sakayu
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p. 159 - 163
(2007/10/03)
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- Simple method of preparation of methyl trans-10,cis-12- and cis-9,trans-11-octadecadienoates from methyl linoleate
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Pure conjugated isomers of linoleic acid were prepared on a large scale by alkali-isomerization of purified methyl linoleate. The methyl esters of alkali-isomerized linoleic acid contained mainly the methyl cis-9,trans-11- and trans-10,cis-12-octadecadienoates (44 and 47%, respectively). These two isomers were then separated and purified by a series of low-temperature crystallizations from acetone. The isomeric purity obtained for the cis-9,trans-11-octadecadienoate isomer was >90% and that of the trans-10,cis-12-octadecadienoate isomer was 89 to 97%. The isolated yield of the two isomers corresponded to 18 and 25.7%, respectively, of the starting material. The structure of the two isomers was confirmed using partial hydrazine reduction, silver nitrate-thin-layer chromatography of the resulting monoenes and gas chromatography coupled with mass spectrometry of the 4,4-dimethyloxazoline derivatives. Fourier transform infrared spectroscopy of the monoenes gave the confirmation of the geometry of each double bond.
- Berdeaux,Voinot,Angioni,Juaneda,Sebedio
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p. 1749 - 1755
(2007/10/03)
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