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Synthesis of structured phospholipids with conjugated linolenic acid, and evaluation of their physical propertiesQuezada Arboleda, Nathalie 15 May 2009 (has links)
Structured phospholipids with conjugated linolenic acid were produced for potential applications in nutraceuticals and functional foods. Structured phospholipids were synthesized with conjugated linolenic acid (CLnA) from natural sources by catalytic enzymatic reaction. Pomegranate seed oil, as a natural source of CLnA, and an isomerized-concentrated mixture (ICM) of CLnA from flaxseed oil were used for the enzymatic reaction with phosphotidylcholine (PC) using Liposyme TL IM for fatty acid modification at 57 °C for 96 h. The enzymatic process was an effective way to produce structured phospholipids with CLnA. The maximum incorporation of CLnA from pomegranate seed oil and ICM from flaxseed oil into PC was 11.3% and 4.9% after 72 h, respectively. Structured lysophospholipids were also obtained as a result of the enzymatic reaction. The maximum incorporation of CLnA from pomegranate oil and ICM from flaxseed oil into lysophospholipids was 17.2% and 13.5% after 72h, respectively. Physical properties such as dropping point and viscosity at 40 and 50 °C of the structured phospholipids produced were measured when they were added to a chocolate mixture (unsweetened chocolate 94.6%, coconut oil 5% and 0.4 % phospholipids). Two controls were used for comparison: the chocolate mixture without phospholipids and the chocolate mixture with Lipoid S100 (phosphatidylcholine 94%). Structured phospholipids with CLnA showed lower dropping point and viscosities than the controls. Oil-in-water emulsions were prepared with whey protein (1%), soy bean oil (10%) and phospholipids (0.5%) in a high pressure homogenizer at 20MPa. The emulsion stability of the emulsions prepared, control (without phospholipids), Lipoid S 100 and structured phospholipids with CLnA were determined by visual observation of phase separation. The structured phospholipids emulsion showed higher emulsion stability than the controls. This emulsion was stable up to 108 h while the emulsion without phospholipid and Lipoid S100 were 48 h and 96 h stable, respectively. Oxidative stability of the emulsions prepared was determined by measuring the peroxide value and p-anisidine value after 1, 3 and 7 days at 50 °C. Oil was extracted from the emulsions using isooctane:isopropanol (3:2 v/v). The structured phospholipid emulsions showed lower oxidative stability than the controls.
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Synthesis of structured phospholipids with conjugated linolenic acid, and evaluation of their physical propertiesQuezada Arboleda, Nathalie 15 May 2009 (has links)
Structured phospholipids with conjugated linolenic acid were produced for potential applications in nutraceuticals and functional foods. Structured phospholipids were synthesized with conjugated linolenic acid (CLnA) from natural sources by catalytic enzymatic reaction. Pomegranate seed oil, as a natural source of CLnA, and an isomerized-concentrated mixture (ICM) of CLnA from flaxseed oil were used for the enzymatic reaction with phosphotidylcholine (PC) using Liposyme TL IM for fatty acid modification at 57 °C for 96 h. The enzymatic process was an effective way to produce structured phospholipids with CLnA. The maximum incorporation of CLnA from pomegranate seed oil and ICM from flaxseed oil into PC was 11.3% and 4.9% after 72 h, respectively. Structured lysophospholipids were also obtained as a result of the enzymatic reaction. The maximum incorporation of CLnA from pomegranate oil and ICM from flaxseed oil into lysophospholipids was 17.2% and 13.5% after 72h, respectively. Physical properties such as dropping point and viscosity at 40 and 50 °C of the structured phospholipids produced were measured when they were added to a chocolate mixture (unsweetened chocolate 94.6%, coconut oil 5% and 0.4 % phospholipids). Two controls were used for comparison: the chocolate mixture without phospholipids and the chocolate mixture with Lipoid S100 (phosphatidylcholine 94%). Structured phospholipids with CLnA showed lower dropping point and viscosities than the controls. Oil-in-water emulsions were prepared with whey protein (1%), soy bean oil (10%) and phospholipids (0.5%) in a high pressure homogenizer at 20MPa. The emulsion stability of the emulsions prepared, control (without phospholipids), Lipoid S 100 and structured phospholipids with CLnA were determined by visual observation of phase separation. The structured phospholipids emulsion showed higher emulsion stability than the controls. This emulsion was stable up to 108 h while the emulsion without phospholipid and Lipoid S100 were 48 h and 96 h stable, respectively. Oxidative stability of the emulsions prepared was determined by measuring the peroxide value and p-anisidine value after 1, 3 and 7 days at 50 °C. Oil was extracted from the emulsions using isooctane:isopropanol (3:2 v/v). The structured phospholipid emulsions showed lower oxidative stability than the controls.
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Synthèse enzymatique de phospholipides structurés riches en DHA / Enzymatic synthesis of structured phospholipids rich in DHAHubert, Florence 12 July 2018 (has links)
Ce travail étudie l’obtention de phospholipides structurés enrichis en DHA et en acide caprylique (PC DHA-C8) par voie enzymatique. Deux voies de synthèse sont étudiées, l’acidolyse et l’estérification. Suite à un criblage enzymatique, la lipase retenue pour les deux voies de synthèse est TL-IM. Une optimisation des paramètres de la réaction d’acidolyse a été réalisée entre l’acide caprylique (C8:0) et la phosphatidylcholine de tournesol (PC) par le biais d’un plan d’expériences. Les conditions optimales déterminées sont une température de 38°C, une activité de l’eau de 0,7, une quantité d’enzyme de 15% de la masse en substrat ainsi qu’un rapport molaire C8:0/PC de 18. Ces conditions ont ensuite été utilisées pour l’acidolyse de phospholipides microalgaux riches en DHA issus de la microalgue Tisochrysis lutea afin d’obtenir de la PC DHA-C8. Les résultats n’ont pas été concluants. L’autre voie de synthèse étudiée est l’estérification par des lipases de la GPC, de l’acide caprylique et du DHA en milieu fondu. Cette réaction a été optimisée par la technique du pas par pas. Les paramètres étudiés sont la température, la quantité d’enzyme, le rapport molaire GPC/C8:0/DHA et l’application d’un vide. Pour l’obtention de PC DHA-C8, il faut fixer chacun de ces paramètres respectivement de la sorte : 45°C, 20% d’enzyme, un rapport molaire de 1/3/15 et un vide de 100 mbar. La production de PC DHA-C8, bien qu’optimisée ne dépasse pas 2% de rendement. Cependant, durant cette expérience, il a été constaté une forte production de LPC DHA, atteignant 16% sans optimisation des paramètres de synthèse. / The enzymatic synthesis of structured phsopholipids enriched in DHA and caprylic acid (PC DHA-C8) is studied. Two different ways are studied, acidolysis and esterification. An enzymatic screening led to the choice of the immobilized lipase from Thermomyces lanuginosa (TL-IM) for the 2 reactions. Parameters of the acidolysis reaction between carpylic acid (C8:0) and sunflower phosphatidylcholine (PC) were optimized by means of an experimental design. The optimum conditions determined are a temperature of 38°C, an aw of 0.7, an amount of enzyme of 15% of the mass of substrate and a molar ratio of C8:0/PC of 18. These conditions were applied to the acidolysis of microalgal phospholipids from T. lutea, rich in DHA, in order to produce PC DHA-C8. The other studied reaction is the lipase catalyzed esterification of GPC with C8:0 and DHA in a solvent-free medium This reaction has been optimized by studying each factor independently. The parameters studied are the temperature, the amount of lipase, the molar ratio GPC/C8:0/DHA and the use of reduced pressure. In order to obtain PC DHA-C8, each of theses parameters are respectively set at: 45°C, 20% of enzyme, a molar ratio of 1/3/15 and a pressure of 100 mbar. The production of PC DHA-C8, although optimized, does not exceed a yield of 2%. However, during this experiment, a high production of LPC DHA is observed, up to 16% without optimization of the synthesis parameter.
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