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Artemis Karaali - One of the best experts on this subject based on the ideXlab platform.
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human milk fat substitutes containing omega 3 fatty acids
Journal of Agricultural and Food Chemistry, 2006Co-Authors: Nese Sahin, Casimir C. Akoh, Artemis KaraaliAbstract:Structured lipids resembling human milk fat (HMF) enriched with omega-3 fatty acids were synthesized by enzymatic acidolysis reactions between Tripalmitin, hazelnut oil fatty acids (FA), and omega-3 FA concentrate. Response surface methodology was used to model and optimize the incorporation of omega-3 FA and oleic acid into Tripalmitin, in hexane, using immobilized sn-1,3-specific lipase, Lipozyme RM IM. The three factors chosen were substrate molar ratio, reaction temperature, and reaction time. Good quadratic models were obtained for the incorporation of eicosapentaenoic acid (EPA) plus docosahexaenoic acid (DHA) (response 1) and oleic acid (response 2) by multiple regression and backward elimination. The determination coefficient (R2) value for the models was 0.95. The adjusted R2 values were 0.91 and 0.92 for responses 1 and 2, respectively. The optimal conditions generated from the models for the targeted total EPA and DHA (5%) and oleic acid (40%) incorporation were 12.4 mol/mol, 55 degrees C, and 24 h for substrate ratio, temperature, and time, respectively. The model was verified, which led to the production of a HMF ingredient with 76.6% palmitic acid at the sn-2 position.
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enzymatic production of human milk fat substitutes containing γ linolenic acid optimization of reactions by response surface methodology
Journal of the American Oil Chemists' Society, 2005Co-Authors: Casimir C. Akoh, Nese Sahin, Artemis KaraaliAbstract:Structured lipids resembling human milk fat and containing GLA were synthesized by an enzymatic interesterification between Tripalmitin, hazelnut oil FA, and GLA in n-hexane. Commercially immobilized 1,3-specific lipases, lipozyme® RM IM and Lipozyme® TL IM, were used as the biocatalysts. The effect of these enzymes on the incorporation levels was investigated. A central composite design with five levels and three factors—substrate ratio, reaction temperature, and time—were used to model and optimize the reaction conditions via response surface methodology. Good quadratic models were obtained for the incorporation of GLA (response 1) and oleic acid (response 2) by multiple regression and backward elimination. The determination coefficient (R 2) values for the models were found to be 0.92 and 0.94 for the reactions catalyzed by Lipozyme RM IM, and 0.92 and 0.88 for the reactions catalyzed by Lipozyme TL IM, respecitively. The optimal conditions generated from the models for the targeted GLA (10%) and oleic acid (45%) incorporation were 14.8 mol/mol, 55°C, and 24 h; 14 mol/mol, 55°C, and 24 h for substrate ratio (moles total FA/mol Tripalmitin), temperature and time for the reactions catalyzed by Lipozyme RM IM and Lipozyme TL IM, respectively. Human milk fat substitutes containing GLA that can be included in infant formulas were success-fully produced using both Lipozyme RM IM and Lipozyme TL IM enzymes. The effect of the two enzymes on the incorporation of GLA and oleic acid were found to be similar.
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lipase catalyzed acidolysis of Tripalmitin with hazelnut oil fatty acids and stearic acid to produce human milk fat substitutes
Journal of Agricultural and Food Chemistry, 2005Co-Authors: Nese Sahin, Casimir C. Akoh, Artemis KaraaliAbstract:Structured lipids (SLs) containing palmitic, oleic, stearic, and linoleic acids, resembling human milk fat (HMF), were synthesized by enzymatic acidolysis reactions between Tripalmitin, hazelnut oil fatty acids, and stearic acid. Commercially immobilized sn-1,3-specific lipase, Lipozyme RM IM, obtained from Rhizomucor miehei was used as the biocatalyst for the enzymatic acidolysis reactions. The effects of substrate molar ratio, reaction temperature, and reaction time on the incorporation of stearic and oleic acids were investigated. The acidolysis reactions were performed by incubating 1:1.5:0.5, 1:3:0.75, 1:6:1, 1:9:1.25, and 1:12:1.5 substrate molar ratios of Tripalmitin/hazelnut oil fatty acids/stearic acid in 3 mL of n-hexane at 55, 60, and 65 °C using 10% (total weight of substrates) of Lipozyme RM IM for 3, 6, 12, and 24 h. The fatty acid composition of reaction products was analyzed by gas−liquid chromatography (GLC). The fatty acids at the sn-2 position were identified after pancreatic lipase hyd...
Fumiyuki Nakashio - One of the best experts on this subject based on the ideXlab platform.
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enzymatic interesterification of triglyceride with surfactant coated lipase in organic media
Biotechnology and Bioengineering, 1995Co-Authors: Masahiro Goto, Muneharu Goto, Noriho Kamiya, Fumiyuki NakashioAbstract:Several surfactant-coated enzymes have been prepared by coating lipases of various origins with a nonionic surfactant, glutamic acid dioleylester ribitol (2C18Δ9GE). Enzymatic interesterification of Tripalmitin with oleic acid using the surfactant-coated lipase was carried out in organic media. The surfactant-coated lipases could effectively catalyze the interesterification of glycerides better than did the powder lipases. A suitable organic solvent was an aliphatic hydrocarbon such as isooctane. The enzymatic activity for the interesterification strongly depended on the origin of the lipase. The surfactant-coated lipase prepared by Mucor javanicus showed the highest enzymatic activity for the interesterification of glycerides, although its powder lipase did not show enzymatic activity. Selective interesterification of glycerides could be performed by adjusting the concentration ratio of oleic acid to Tripalmitin in isooctane. Di-substituted glyceride could be selectively produced when the concentration ratio of carboxylic acid to glycerides was 7. © 1995 John Wiley & Sons, Inc.
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Enzymatic interesterification of triglyceride with surfactant-coated lipase in organic media.
Biotechnology and bioengineering, 1995Co-Authors: Masahiro Goto, Muneharu Goto, Noriho Kamiya, Fumiyuki NakashioAbstract:Several surfactant-coated enzymes have been prepared by coating lipases of various origins with a nonionic surfactant, glutamic acid dioleylester ribitol (2C(18)Delta(9)GE). Enzymatic interesterification of Tripalmitin with oleic acid using the surfactant-coated lipase was carried out in organic media. The surfactant-coated lipases could effectively catalyze the interesterification of glycerides better than did the powder lipases. A suitable organic solvent was an aliphatic hydrocarbon such as isooctane. The enzymatic activity for the interesterification strongly depended on the origin of the lipase. The surfactant-coated lipase prepared by Mucor javanicus showed the highest enzymatic activity for the interesterification of glycerides, although its powder lipase did not show enzymatic activity. Selective interesterification of glycerides could be performed by adjusting the concentration ratio of oleic acid to Tripalmitin in isooctane. Di-substituted glyceride could be selectively produced when the concentration ratio of carboxylic acid to glycerides was 7. (c) 1995 John Wiley & Sons, Inc.
D. J. Mcclements - One of the best experts on this subject based on the ideXlab platform.
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effect of omega 3 fatty acids on crystallization polymorphic transformation and stability of Tripalmitin solid lipid nanoparticle suspensions
Crystal Growth & Design, 2009Co-Authors: T. S. Awad, T. Helgason, J. Weiss, Eric A Decker, D. J. McclementsAbstract:We examined the effect of lipid phase composition on the crystallization, polymorphic transition and stability of solid lipid nanoparticle (SLN) suspensions. A series of fine-disperse oil-in-water emulsions was prepared at an elevated temperature (75 °C) from a lipid phase containing different amounts of a high melting lipid (Tripalmitin) and a low melting lipid (fish oil). These emulsions were cooled to induce crystallization and form SLN suspensions. In the absence of fish oil, the SLN suspensions formed a gel after the emulsified Tripalmitin crystallized, which was attributed to particle shape changes leading to aggregation and network formation. Light scattering and rheology measurements indicated that incorporation of fish oil into the lipid phase (≥10 wt %) increased the stability of SLN to aggregation. DSC measurements suggested that crystallization, melting, and polymorphic transitions of SLN were influenced by the amount of fish oil incorporated. The rate of α- to β-polymorphic transitions of tri...
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influence of polymorphic transformations on gelation of Tripalmitin solid lipid nanoparticle suspensions
Journal of the American Oil Chemists' Society, 2008Co-Authors: T. Helgason, T. S. Awad, K. Kristbergsson, D. J. Mcclements, J. WeissAbstract:Solid lipid nanoparticle (SLN) suspensions, which consist of submicron-sized crystalline lipid particles dispersed within an aqueous medium, can be used to encapsulate, protect and deliver lipophilic functional components. Nevertheless, SLN suspensions are susceptible to particle aggregation and gelation during their preparation and storage, which potentially limits their industrial utilization. In this study, we examined the aggregation and gelation behavior of SLN suspensions composed of 10 wt% Tripalmitin particles (r < 150 nm) stabilized by 1.5% Tween 20. The Tripalmitin and aqueous surfactant solution were homogenized above the lipid melting temperature and cooled under controlled conditions to initiate SLN formation. The aggregation and gelation of SLN suspensions during storage was then examined by shear rheometry, differential scanning calorimetry (DSC), light scattering and microscopy. Rheology measurements indicated that gelation times decreased with increasing storage temperature, e.g., samples formed weak gels after 62, 23, and 10 min at 1, 5, and 10 °C, respectively. DSC revealed increasingly rapid α- to β-polymorphic transformations in SLN dispersions stored at 1, 5, and 10 °C, respectively. We propose that the observed aggregation and gelation of SLN suspensions are associated with a change in the shape of the nanoparticles from spherical (α-form) to non-spherical (β-form) when they undergo the polymorphic transition. When they change shape there is no longer sufficient surfactant present to completely cover the lipid phase, which promotes particle aggregation through hydrophobic attraction. Our results have important implications for the design and fabrication of stable SLN suspensions.
Nese Sahin - One of the best experts on this subject based on the ideXlab platform.
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human milk fat substitutes containing omega 3 fatty acids
Journal of Agricultural and Food Chemistry, 2006Co-Authors: Nese Sahin, Casimir C. Akoh, Artemis KaraaliAbstract:Structured lipids resembling human milk fat (HMF) enriched with omega-3 fatty acids were synthesized by enzymatic acidolysis reactions between Tripalmitin, hazelnut oil fatty acids (FA), and omega-3 FA concentrate. Response surface methodology was used to model and optimize the incorporation of omega-3 FA and oleic acid into Tripalmitin, in hexane, using immobilized sn-1,3-specific lipase, Lipozyme RM IM. The three factors chosen were substrate molar ratio, reaction temperature, and reaction time. Good quadratic models were obtained for the incorporation of eicosapentaenoic acid (EPA) plus docosahexaenoic acid (DHA) (response 1) and oleic acid (response 2) by multiple regression and backward elimination. The determination coefficient (R2) value for the models was 0.95. The adjusted R2 values were 0.91 and 0.92 for responses 1 and 2, respectively. The optimal conditions generated from the models for the targeted total EPA and DHA (5%) and oleic acid (40%) incorporation were 12.4 mol/mol, 55 degrees C, and 24 h for substrate ratio, temperature, and time, respectively. The model was verified, which led to the production of a HMF ingredient with 76.6% palmitic acid at the sn-2 position.
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enzymatic production of human milk fat substitutes containing γ linolenic acid optimization of reactions by response surface methodology
Journal of the American Oil Chemists' Society, 2005Co-Authors: Casimir C. Akoh, Nese Sahin, Artemis KaraaliAbstract:Structured lipids resembling human milk fat and containing GLA were synthesized by an enzymatic interesterification between Tripalmitin, hazelnut oil FA, and GLA in n-hexane. Commercially immobilized 1,3-specific lipases, lipozyme® RM IM and Lipozyme® TL IM, were used as the biocatalysts. The effect of these enzymes on the incorporation levels was investigated. A central composite design with five levels and three factors—substrate ratio, reaction temperature, and time—were used to model and optimize the reaction conditions via response surface methodology. Good quadratic models were obtained for the incorporation of GLA (response 1) and oleic acid (response 2) by multiple regression and backward elimination. The determination coefficient (R 2) values for the models were found to be 0.92 and 0.94 for the reactions catalyzed by Lipozyme RM IM, and 0.92 and 0.88 for the reactions catalyzed by Lipozyme TL IM, respecitively. The optimal conditions generated from the models for the targeted GLA (10%) and oleic acid (45%) incorporation were 14.8 mol/mol, 55°C, and 24 h; 14 mol/mol, 55°C, and 24 h for substrate ratio (moles total FA/mol Tripalmitin), temperature and time for the reactions catalyzed by Lipozyme RM IM and Lipozyme TL IM, respectively. Human milk fat substitutes containing GLA that can be included in infant formulas were success-fully produced using both Lipozyme RM IM and Lipozyme TL IM enzymes. The effect of the two enzymes on the incorporation of GLA and oleic acid were found to be similar.
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lipase catalyzed acidolysis of Tripalmitin with hazelnut oil fatty acids and stearic acid to produce human milk fat substitutes
Journal of Agricultural and Food Chemistry, 2005Co-Authors: Nese Sahin, Casimir C. Akoh, Artemis KaraaliAbstract:Structured lipids (SLs) containing palmitic, oleic, stearic, and linoleic acids, resembling human milk fat (HMF), were synthesized by enzymatic acidolysis reactions between Tripalmitin, hazelnut oil fatty acids, and stearic acid. Commercially immobilized sn-1,3-specific lipase, Lipozyme RM IM, obtained from Rhizomucor miehei was used as the biocatalyst for the enzymatic acidolysis reactions. The effects of substrate molar ratio, reaction temperature, and reaction time on the incorporation of stearic and oleic acids were investigated. The acidolysis reactions were performed by incubating 1:1.5:0.5, 1:3:0.75, 1:6:1, 1:9:1.25, and 1:12:1.5 substrate molar ratios of Tripalmitin/hazelnut oil fatty acids/stearic acid in 3 mL of n-hexane at 55, 60, and 65 °C using 10% (total weight of substrates) of Lipozyme RM IM for 3, 6, 12, and 24 h. The fatty acid composition of reaction products was analyzed by gas−liquid chromatography (GLC). The fatty acids at the sn-2 position were identified after pancreatic lipase hyd...
Masahiro Goto - One of the best experts on this subject based on the ideXlab platform.
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enzymatic interesterification of triglyceride with surfactant coated lipase in organic media
Biotechnology and Bioengineering, 1995Co-Authors: Masahiro Goto, Muneharu Goto, Noriho Kamiya, Fumiyuki NakashioAbstract:Several surfactant-coated enzymes have been prepared by coating lipases of various origins with a nonionic surfactant, glutamic acid dioleylester ribitol (2C18Δ9GE). Enzymatic interesterification of Tripalmitin with oleic acid using the surfactant-coated lipase was carried out in organic media. The surfactant-coated lipases could effectively catalyze the interesterification of glycerides better than did the powder lipases. A suitable organic solvent was an aliphatic hydrocarbon such as isooctane. The enzymatic activity for the interesterification strongly depended on the origin of the lipase. The surfactant-coated lipase prepared by Mucor javanicus showed the highest enzymatic activity for the interesterification of glycerides, although its powder lipase did not show enzymatic activity. Selective interesterification of glycerides could be performed by adjusting the concentration ratio of oleic acid to Tripalmitin in isooctane. Di-substituted glyceride could be selectively produced when the concentration ratio of carboxylic acid to glycerides was 7. © 1995 John Wiley & Sons, Inc.
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Enzymatic interesterification of triglyceride with surfactant-coated lipase in organic media.
Biotechnology and bioengineering, 1995Co-Authors: Masahiro Goto, Muneharu Goto, Noriho Kamiya, Fumiyuki NakashioAbstract:Several surfactant-coated enzymes have been prepared by coating lipases of various origins with a nonionic surfactant, glutamic acid dioleylester ribitol (2C(18)Delta(9)GE). Enzymatic interesterification of Tripalmitin with oleic acid using the surfactant-coated lipase was carried out in organic media. The surfactant-coated lipases could effectively catalyze the interesterification of glycerides better than did the powder lipases. A suitable organic solvent was an aliphatic hydrocarbon such as isooctane. The enzymatic activity for the interesterification strongly depended on the origin of the lipase. The surfactant-coated lipase prepared by Mucor javanicus showed the highest enzymatic activity for the interesterification of glycerides, although its powder lipase did not show enzymatic activity. Selective interesterification of glycerides could be performed by adjusting the concentration ratio of oleic acid to Tripalmitin in isooctane. Di-substituted glyceride could be selectively produced when the concentration ratio of carboxylic acid to glycerides was 7. (c) 1995 John Wiley & Sons, Inc.
