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The phase behaviour of food surfactantsMorley, Wayne Gerald January 1995 (has links)
No description available.
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Effects of monoglycerides on rhodamine 123 accumulation, estradiol 17 β-D-glucuronide bidirectional transport and MRP2 protein expression within Caco-2 cellsJia, Xi Jessica 11 1900 (has links)
Purpose: Oral drug development had been hindered by the bioavailability issue
despite vast market popularity. Lipid excipients have shown to enhance
bioavailability of several reformulated hydrophobic oral drugs, yet the underlying
mechanisms of action by lipids are still unclear. One proposed mechanism is that
lipid could facilitate drug uptake by altering the activities of apical membrane
intestinal efflux transporters. Thus, this study aimed to investigate the effects of
specific monoglycerides on the efflux activity and protein expression of multidrug
resistance-associated protein 2 (MRP2) in vitro.
Methods: A preliminary study was first conducted to determine the effect of
Peceol®, a mono- and di-glyceride mixture, on MPR2 efflux activity. Then, the 24-
hour non-cytotoxic ranges of specific monoglycerides (1-monopalmitin, 1-
monostearin and 1-monoolein) were determined using MTS and LDH assays in
Caco-2 cells. Then, the effects of chosen monoglycerides on the functional
activity of MRP2 were assessed via rhodamine 123 (Rh123) accumulation and
estradiol 17 β-D-glucuronide(E₂17βG) bidirectional transport studies. The dose
responses of Rh123 accumulation with each monoglyceride treatment were also
determined. Lastly, Western blotting was used to probe the monoglycerides
effect on MRP2 protein expression.
Results: In the preliminary study, significant increase in Rh123 accumulation
and decrease in E₂17βG efflux ratio were observed in Peceol® treated cells. The
non-cytotoxic concentration ranges for 1-monopalmitin, 1-monostearin and 1-
monoolein were within 1 mM, 1 mM and 500 μM, respectively. Cells treated with
1 mM 1-monoplamitin, 1 mM 1-monostearin, 500 μM 1-monoolein and 50 μM
MK571 (a MRP2 inhibitor) resulted in significant increases in Rh123
accumulation and decreases in E₂17βG efflux ratio compared to the control
(medium treated only). The three monoglycerides did not show Rh123
accumulation in a dose-responsive manner. MRP2 protein expressions in 1-
monopalmitin and 1-monoolein treated cells were decreased by 19% and 35%,
respectively; however, there was no change of MRP2 protein expression in 1-
monostearin treated cells.
Conclusions: These findings suggested that 1-monoolein, 1-monostearin and 1-
monopalmitin could attenuate the activity of MRP2 and possibly other efflux
transporters in Caco-2 cells. The reduction of efflux activity of MRP2 by 1-
monoolein treatment could be partially explained by the non-specific down
regulation of MRP2 protein expression.
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Effects of monoglycerides on rhodamine 123 accumulation, estradiol 17 β-D-glucuronide bidirectional transport and MRP2 protein expression within Caco-2 cellsJia, Xi Jessica 11 1900 (has links)
Purpose: Oral drug development had been hindered by the bioavailability issue
despite vast market popularity. Lipid excipients have shown to enhance
bioavailability of several reformulated hydrophobic oral drugs, yet the underlying
mechanisms of action by lipids are still unclear. One proposed mechanism is that
lipid could facilitate drug uptake by altering the activities of apical membrane
intestinal efflux transporters. Thus, this study aimed to investigate the effects of
specific monoglycerides on the efflux activity and protein expression of multidrug
resistance-associated protein 2 (MRP2) in vitro.
Methods: A preliminary study was first conducted to determine the effect of
Peceol®, a mono- and di-glyceride mixture, on MPR2 efflux activity. Then, the 24-
hour non-cytotoxic ranges of specific monoglycerides (1-monopalmitin, 1-
monostearin and 1-monoolein) were determined using MTS and LDH assays in
Caco-2 cells. Then, the effects of chosen monoglycerides on the functional
activity of MRP2 were assessed via rhodamine 123 (Rh123) accumulation and
estradiol 17 β-D-glucuronide(E₂17βG) bidirectional transport studies. The dose
responses of Rh123 accumulation with each monoglyceride treatment were also
determined. Lastly, Western blotting was used to probe the monoglycerides
effect on MRP2 protein expression.
Results: In the preliminary study, significant increase in Rh123 accumulation
and decrease in E₂17βG efflux ratio were observed in Peceol® treated cells. The
non-cytotoxic concentration ranges for 1-monopalmitin, 1-monostearin and 1-
monoolein were within 1 mM, 1 mM and 500 μM, respectively. Cells treated with
1 mM 1-monoplamitin, 1 mM 1-monostearin, 500 μM 1-monoolein and 50 μM
MK571 (a MRP2 inhibitor) resulted in significant increases in Rh123
accumulation and decreases in E₂17βG efflux ratio compared to the control
(medium treated only). The three monoglycerides did not show Rh123
accumulation in a dose-responsive manner. MRP2 protein expressions in 1-
monopalmitin and 1-monoolein treated cells were decreased by 19% and 35%,
respectively; however, there was no change of MRP2 protein expression in 1-
monostearin treated cells.
Conclusions: These findings suggested that 1-monoolein, 1-monostearin and 1-
monopalmitin could attenuate the activity of MRP2 and possibly other efflux
transporters in Caco-2 cells. The reduction of efflux activity of MRP2 by 1-
monoolein treatment could be partially explained by the non-specific down
regulation of MRP2 protein expression.
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Effects of monoglycerides on rhodamine 123 accumulation, estradiol 17 β-D-glucuronide bidirectional transport and MRP2 protein expression within Caco-2 cellsJia, Xi Jessica 11 1900 (has links)
Purpose: Oral drug development had been hindered by the bioavailability issue
despite vast market popularity. Lipid excipients have shown to enhance
bioavailability of several reformulated hydrophobic oral drugs, yet the underlying
mechanisms of action by lipids are still unclear. One proposed mechanism is that
lipid could facilitate drug uptake by altering the activities of apical membrane
intestinal efflux transporters. Thus, this study aimed to investigate the effects of
specific monoglycerides on the efflux activity and protein expression of multidrug
resistance-associated protein 2 (MRP2) in vitro.
Methods: A preliminary study was first conducted to determine the effect of
Peceol®, a mono- and di-glyceride mixture, on MPR2 efflux activity. Then, the 24-
hour non-cytotoxic ranges of specific monoglycerides (1-monopalmitin, 1-
monostearin and 1-monoolein) were determined using MTS and LDH assays in
Caco-2 cells. Then, the effects of chosen monoglycerides on the functional
activity of MRP2 were assessed via rhodamine 123 (Rh123) accumulation and
estradiol 17 β-D-glucuronide(E₂17βG) bidirectional transport studies. The dose
responses of Rh123 accumulation with each monoglyceride treatment were also
determined. Lastly, Western blotting was used to probe the monoglycerides
effect on MRP2 protein expression.
Results: In the preliminary study, significant increase in Rh123 accumulation
and decrease in E₂17βG efflux ratio were observed in Peceol® treated cells. The
non-cytotoxic concentration ranges for 1-monopalmitin, 1-monostearin and 1-
monoolein were within 1 mM, 1 mM and 500 μM, respectively. Cells treated with
1 mM 1-monoplamitin, 1 mM 1-monostearin, 500 μM 1-monoolein and 50 μM
MK571 (a MRP2 inhibitor) resulted in significant increases in Rh123
accumulation and decreases in E₂17βG efflux ratio compared to the control
(medium treated only). The three monoglycerides did not show Rh123
accumulation in a dose-responsive manner. MRP2 protein expressions in 1-
monopalmitin and 1-monoolein treated cells were decreased by 19% and 35%,
respectively; however, there was no change of MRP2 protein expression in 1-
monostearin treated cells.
Conclusions: These findings suggested that 1-monoolein, 1-monostearin and 1-
monopalmitin could attenuate the activity of MRP2 and possibly other efflux
transporters in Caco-2 cells. The reduction of efflux activity of MRP2 by 1-
monoolein treatment could be partially explained by the non-specific down
regulation of MRP2 protein expression. / Pharmaceutical Sciences, Faculty of / Graduate
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Desenvolvimento de poliuretano empregando poliol de óleo de andiroba obtido via catálise enzimáticaSilva, João Antonio Pessoa da January 2017 (has links)
O objetivo deste trabalho foi estudar a síntese de poliol de óleo de andiroba (POA) e utilizá-lo como matéria prima para a produção de poliuretanos (PUs). A síntese do poliol foi realizada por catálise enzimática com a lipase comercial Novozym 435. A reação foi feita em reator de leito fixo, empregando óleo de andiroba e glicerol (GLI) como substrato, em proporção molar 2:1, e t-butanol (TB) como solvente. Foram avaliadas as relações solvente:substrato de 50, 100 e 150 % e temperaturas de 40, 50 e 60 °C. Os produtos da reação, monoglicerídeos (MAGs), diglicerídeos (DAGs) e triglicerídeos (TAGs), foram quantificados através de cromatografia líquida de alta eficiência (CLAE), índice de acidez (IA) e espectroscopia de infravermelho com transformada de Fourier (FTIR). O poliol obtido na condição 50°C e 150 % solvente foi escolhido para a produção dos PUs, devido à sua maior quantidade de MAG (66 %) e menor de DAG (28 %) e TAG (5 %). Os PUs foram produzidos empregando-se poliol, biureto de hexametileno de diisocianato (BHD), dibutil dilaurato de estanho como catalisador e, apenas para produção de espumas, água destilada como agente expansor. Utilizaram-se razões NCO/OH de 0,8 e 1 para os filmes e NCO/OH=1 para as espumas. Na produção das espumas o POA foi combinado com GLI nas proporções de 25 e 50 %. A formação de PU a partir do poliol de andiroba foi confirmada por FTIR e análise termogravimétrica. Os filmes de PU obtidos apresentaram caráter hidrofílico e defeitos de superfície devido à formação de bolhas durante o processo de formação. A resistência à tração dos filmes mostrou-se dependente da quantidade de poliol, não tendo sido possível a obtenção de espumas sem a adição de glicerol. A resistência mecânica das espumas produzidas foi baixa, devido à baixa funcionalidade do POA e a presença de DAG e TAG, porém similar àquela reportada na literatura para alguns outros tipos de espumas de PU. Assim, este trabalho demonstrou a possibilidade da utilização do óleo de andiroba para a produção de PUs e, com base nas propriedades mecânicas dos materiais produzidos e nas características intrínsecas da andiroba, abre novas possibilidades de desenvolvimento de materiais com potencial para aplicações medicinais. / The goal of this work was to study the synthesis of andiroba oil polyol (AOP) and use it as raw material for the preparation of polyurethanes (PUs). The AOP synthesis was performed by enzymatic catalysis employing the commercial lipase Novozym 435. The reaction was carried out in a fixed bed reactor using andiroba oil and glycerol (GLI) at 1:2 molar ratio as substrate, and t-butanol (TB) as solvent. Solvent:substrate ratios of 50, 100 and 150 % and temperatures of 40, 50 and 60 °C were evaluated. The reaction products, monoglycerides (MAGs), diglycerides (DAGs) and triglycerides (TAGs), were quantified through high performance liquid chromatography (HPLC), acidity index (IA), and Fourier transform infrared spectroscopy (FTIR). The polyol obtained at 50 °C and 150% solvent was chosen for PU production, due to its higher content of MAG (66 %) and lower content of DAG (28 %) and TAG (5 %). PUs were prepared from AOP, hexamethylene diisocyanate biuret (BHD), dibutyl-tin dilaurate as catalyst, and, for the foams, distilled water as blowing agent. NCO/OH ratios of 0.8 and 1 were used for the films. For the foams, NCO/OH = 1 and AOP/GLI blends with 25 and 50 % of glycerol were employed. The formation of PU from the AOP was confirmed by FTIR and thermogravimetric analysis. The obtained PU films presented hydrophilicity and surface defects due to the formation of bubbles during the formation process. The tensile strength of the films was shown to be dependent on the amount of polyol, and it was not possible to obtain foams without the addition of glycerol. The mechanical strength of the foams produced was low, due to the low functionality of the POA and the presence of DAG and TAG, but similar to that reported in the literature for some other types of PU foams. Thus, this work demonstrated the possibility of using andiroba oil for the production of PUs. Besides, based on the mechanical properties of the materials produced and the intrinsic characteristics of andiroba, it opens new possibilities for the development of materials with potential for medicinal applications.
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Studies of interfacial organizations and interactions of multi-component phospholipid membranes /Wang, Zhining. January 2009 (has links)
Includes bibliographical references.
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Desenvolvimento de poliuretano empregando poliol de óleo de andiroba obtido via catálise enzimáticaSilva, João Antonio Pessoa da January 2017 (has links)
O objetivo deste trabalho foi estudar a síntese de poliol de óleo de andiroba (POA) e utilizá-lo como matéria prima para a produção de poliuretanos (PUs). A síntese do poliol foi realizada por catálise enzimática com a lipase comercial Novozym 435. A reação foi feita em reator de leito fixo, empregando óleo de andiroba e glicerol (GLI) como substrato, em proporção molar 2:1, e t-butanol (TB) como solvente. Foram avaliadas as relações solvente:substrato de 50, 100 e 150 % e temperaturas de 40, 50 e 60 °C. Os produtos da reação, monoglicerídeos (MAGs), diglicerídeos (DAGs) e triglicerídeos (TAGs), foram quantificados através de cromatografia líquida de alta eficiência (CLAE), índice de acidez (IA) e espectroscopia de infravermelho com transformada de Fourier (FTIR). O poliol obtido na condição 50°C e 150 % solvente foi escolhido para a produção dos PUs, devido à sua maior quantidade de MAG (66 %) e menor de DAG (28 %) e TAG (5 %). Os PUs foram produzidos empregando-se poliol, biureto de hexametileno de diisocianato (BHD), dibutil dilaurato de estanho como catalisador e, apenas para produção de espumas, água destilada como agente expansor. Utilizaram-se razões NCO/OH de 0,8 e 1 para os filmes e NCO/OH=1 para as espumas. Na produção das espumas o POA foi combinado com GLI nas proporções de 25 e 50 %. A formação de PU a partir do poliol de andiroba foi confirmada por FTIR e análise termogravimétrica. Os filmes de PU obtidos apresentaram caráter hidrofílico e defeitos de superfície devido à formação de bolhas durante o processo de formação. A resistência à tração dos filmes mostrou-se dependente da quantidade de poliol, não tendo sido possível a obtenção de espumas sem a adição de glicerol. A resistência mecânica das espumas produzidas foi baixa, devido à baixa funcionalidade do POA e a presença de DAG e TAG, porém similar àquela reportada na literatura para alguns outros tipos de espumas de PU. Assim, este trabalho demonstrou a possibilidade da utilização do óleo de andiroba para a produção de PUs e, com base nas propriedades mecânicas dos materiais produzidos e nas características intrínsecas da andiroba, abre novas possibilidades de desenvolvimento de materiais com potencial para aplicações medicinais. / The goal of this work was to study the synthesis of andiroba oil polyol (AOP) and use it as raw material for the preparation of polyurethanes (PUs). The AOP synthesis was performed by enzymatic catalysis employing the commercial lipase Novozym 435. The reaction was carried out in a fixed bed reactor using andiroba oil and glycerol (GLI) at 1:2 molar ratio as substrate, and t-butanol (TB) as solvent. Solvent:substrate ratios of 50, 100 and 150 % and temperatures of 40, 50 and 60 °C were evaluated. The reaction products, monoglycerides (MAGs), diglycerides (DAGs) and triglycerides (TAGs), were quantified through high performance liquid chromatography (HPLC), acidity index (IA), and Fourier transform infrared spectroscopy (FTIR). The polyol obtained at 50 °C and 150% solvent was chosen for PU production, due to its higher content of MAG (66 %) and lower content of DAG (28 %) and TAG (5 %). PUs were prepared from AOP, hexamethylene diisocyanate biuret (BHD), dibutyl-tin dilaurate as catalyst, and, for the foams, distilled water as blowing agent. NCO/OH ratios of 0.8 and 1 were used for the films. For the foams, NCO/OH = 1 and AOP/GLI blends with 25 and 50 % of glycerol were employed. The formation of PU from the AOP was confirmed by FTIR and thermogravimetric analysis. The obtained PU films presented hydrophilicity and surface defects due to the formation of bubbles during the formation process. The tensile strength of the films was shown to be dependent on the amount of polyol, and it was not possible to obtain foams without the addition of glycerol. The mechanical strength of the foams produced was low, due to the low functionality of the POA and the presence of DAG and TAG, but similar to that reported in the literature for some other types of PU foams. Thus, this work demonstrated the possibility of using andiroba oil for the production of PUs. Besides, based on the mechanical properties of the materials produced and the intrinsic characteristics of andiroba, it opens new possibilities for the development of materials with potential for medicinal applications.
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Desenvolvimento de poliuretano empregando poliol de óleo de andiroba obtido via catálise enzimáticaSilva, João Antonio Pessoa da January 2017 (has links)
O objetivo deste trabalho foi estudar a síntese de poliol de óleo de andiroba (POA) e utilizá-lo como matéria prima para a produção de poliuretanos (PUs). A síntese do poliol foi realizada por catálise enzimática com a lipase comercial Novozym 435. A reação foi feita em reator de leito fixo, empregando óleo de andiroba e glicerol (GLI) como substrato, em proporção molar 2:1, e t-butanol (TB) como solvente. Foram avaliadas as relações solvente:substrato de 50, 100 e 150 % e temperaturas de 40, 50 e 60 °C. Os produtos da reação, monoglicerídeos (MAGs), diglicerídeos (DAGs) e triglicerídeos (TAGs), foram quantificados através de cromatografia líquida de alta eficiência (CLAE), índice de acidez (IA) e espectroscopia de infravermelho com transformada de Fourier (FTIR). O poliol obtido na condição 50°C e 150 % solvente foi escolhido para a produção dos PUs, devido à sua maior quantidade de MAG (66 %) e menor de DAG (28 %) e TAG (5 %). Os PUs foram produzidos empregando-se poliol, biureto de hexametileno de diisocianato (BHD), dibutil dilaurato de estanho como catalisador e, apenas para produção de espumas, água destilada como agente expansor. Utilizaram-se razões NCO/OH de 0,8 e 1 para os filmes e NCO/OH=1 para as espumas. Na produção das espumas o POA foi combinado com GLI nas proporções de 25 e 50 %. A formação de PU a partir do poliol de andiroba foi confirmada por FTIR e análise termogravimétrica. Os filmes de PU obtidos apresentaram caráter hidrofílico e defeitos de superfície devido à formação de bolhas durante o processo de formação. A resistência à tração dos filmes mostrou-se dependente da quantidade de poliol, não tendo sido possível a obtenção de espumas sem a adição de glicerol. A resistência mecânica das espumas produzidas foi baixa, devido à baixa funcionalidade do POA e a presença de DAG e TAG, porém similar àquela reportada na literatura para alguns outros tipos de espumas de PU. Assim, este trabalho demonstrou a possibilidade da utilização do óleo de andiroba para a produção de PUs e, com base nas propriedades mecânicas dos materiais produzidos e nas características intrínsecas da andiroba, abre novas possibilidades de desenvolvimento de materiais com potencial para aplicações medicinais. / The goal of this work was to study the synthesis of andiroba oil polyol (AOP) and use it as raw material for the preparation of polyurethanes (PUs). The AOP synthesis was performed by enzymatic catalysis employing the commercial lipase Novozym 435. The reaction was carried out in a fixed bed reactor using andiroba oil and glycerol (GLI) at 1:2 molar ratio as substrate, and t-butanol (TB) as solvent. Solvent:substrate ratios of 50, 100 and 150 % and temperatures of 40, 50 and 60 °C were evaluated. The reaction products, monoglycerides (MAGs), diglycerides (DAGs) and triglycerides (TAGs), were quantified through high performance liquid chromatography (HPLC), acidity index (IA), and Fourier transform infrared spectroscopy (FTIR). The polyol obtained at 50 °C and 150% solvent was chosen for PU production, due to its higher content of MAG (66 %) and lower content of DAG (28 %) and TAG (5 %). PUs were prepared from AOP, hexamethylene diisocyanate biuret (BHD), dibutyl-tin dilaurate as catalyst, and, for the foams, distilled water as blowing agent. NCO/OH ratios of 0.8 and 1 were used for the films. For the foams, NCO/OH = 1 and AOP/GLI blends with 25 and 50 % of glycerol were employed. The formation of PU from the AOP was confirmed by FTIR and thermogravimetric analysis. The obtained PU films presented hydrophilicity and surface defects due to the formation of bubbles during the formation process. The tensile strength of the films was shown to be dependent on the amount of polyol, and it was not possible to obtain foams without the addition of glycerol. The mechanical strength of the foams produced was low, due to the low functionality of the POA and the presence of DAG and TAG, but similar to that reported in the literature for some other types of PU foams. Thus, this work demonstrated the possibility of using andiroba oil for the production of PUs. Besides, based on the mechanical properties of the materials produced and the intrinsic characteristics of andiroba, it opens new possibilities for the development of materials with potential for medicinal applications.
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Otimização da sintese de monoacilglicerois acetilados por via enzimaica / Otimizations of enzymatic synthesis of acetylated monoacylglycerolsCruz, Carla Lea de Camargo Vianna 23 August 2007 (has links)
Orientador: Daniel Barrera Arellano / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-09T03:51:29Z (GMT). No. of bitstreams: 1
Cruz_CarlaLeadeCamargoVianna_D.pdf: 616206 bytes, checksum: 98da89ebbff6356a40ef492ce249aa2f (MD5)
Previous issue date: 2007 / Resumo: Os monoacilgliceróis acetilados (MGA) são produtos de alto valor agregado utilizados em coberturas ou filmes comestíveis, gomas de mascar e produtos farmacêuticos entre outros. Esses são usualmente produzidos através de interesterificação química na presença de catalisadores ácidos ou básicos sob alta temperatura, acima de 200°C, consumindo grande quantidade de energia e produzindo compostos indesejáveis no produto. Além disso, há necessidade de se realizar uma destilação molecular para purificar o produto. A interesterificação enzimática ocorre em condições mais suaves eliminando tais problemas e o processo de purificação pode ser uma destilação simples. Este estudo apresenta um processo de obtenção de MGA via enzimática através de reação de interesterificação, e subseqüente destilação. Foram realizados testes para selecionar os substratos e via de processo com ácido oléico, óleo de soja e gordura parcialmente hidrogenada de soja esterificados com triacetina em diferentes proporções. Foram testadas quatro enzimas diferentes Lipozyme TL 100L, Lipozyme IM, Lipozyme RM IM e Lipozyme TL IM. Após seleção da enzima (Lipozyme TL IM) e substrato (gordura parcialmente hidrogenada) foi realizada a otimização utilizando um desenho experimental fatorial completo 23, totalizando 17 ensaios, sendo 3 pontos centrais e 6 axiais. As variáveis independentes foram: tempo (h), temperatura (°C) e quantidade da enzima (% em relação ao total dos substratos). As variáveis dependentes: rendimento de MGA (%) e relação diacilglicerol/monoacilglicerol, foram determinadas por HPSEC (High Performance Size Exclusion Chromatography). A faixa ótima encontrada foi: 6 horas, 65°C e 4% de enzima em relação ao total de substratos. Nestas condições foi possível produzir MGA em concentrações até 85% após destilação. Testes de reutilização da enzima, com 0,4% de enzima nova adicionados em cada ciclo indicam que após 6 ciclos essa mantém alta atividade. O produto purificado apresentou características similares ao produto comercial / Abstract: Acetylated monoacylglycerols (AMG) are high added value products used in coatings or edible films, bubble gums, pharmaceutical products and others. They are usually produced through chemical interesterification, in the presence of acid or basic catalysts at high temperatures (above 200°C), causing high energy demands, producing undesirable by-products and requiring molecular distillation to purify the product. Enzymatic interesterification occurs in mild conditions, eliminating such problems, and the purification process can be a simple distillation. This study presents an enzymatic process to obtain AMG through the interesterification reaction and subsequent distillation. Trials were carried out to select the substrates and process path using oleic acid, soy oil and partially hydrogenated soy fat, esterified with triacetin in different proportions (1:1.5 and 1:3). Four different enzymes were tested: Lipozyme TL 100L, Lipozyme IM, Lipozyme RM and Lipozyme TL IM. After the selection of the enzyme (Lipozyme TL IM) and the substrate (partially hydrogenated fat), the optimization of the reaction was studied using a 23 complete factorial experimental design, totalizing 17 assays, including 3 central and 6 axial points. The independent variables were: time (h), temperature (°C) and quantity of enzyme (% of total substrates). The dependent variables were: AMG yield (%) and diacylglycerol/monoacylglycerol ratio, analyzed through HPSEC (High Performance Size Exclusion Chromatography). The optimal condition found was 6 hours, 65°C and 4% enzyme with respect to total substrates. Under these conditions, it was possible to produce AMG in concentrations of up to 85% after distillation. Enzyme reutilization trials, adding 0.4% new enzyme to each cycle, indicate that, after 6 cycles, high enzyme activity is maintained. The purified product presented characteristics similar to the commercial product / Doutorado / Doutor em Tecnologia de Alimentos
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Maximizing the use of food emulsifiersBaker, Steven R. January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / J. Scott Smith / Emulsifiers have been and remain highly functional ingredients in the food industry. Emulsifiers contain both hydrophilic and lipophilic parts, resulting in their ability to be useful in foods at very low levels. However, knowledge of why emulsifiers work and how to use them most effectively is reserved for the few scientists who specialize in the discipline. Therefore, a comparison of current emulsifier theory with known emulsifier usage in the industry is beneficial to all who use these ingredients. Current emulsifier theory effectively describes how emulsifiers behave in food systems. Emulsion theory details how emulsifiers facilitate the formation and stability of emulsions through study of the kinetics of food systems. Emulsion theory further relates the ability of emulsifiers to interact with other substances in a food system.
The main interactions concerning emulsifiers are their ability to form mesophases with water, to strengthen or weaken protein interactions, to form complexes with starches, and to promote or subdue fat crystallization. However, industrial applications of emulsifiers indicate areas where exceptions to theory exist. While emulsion theory has been found to effectively describe the individual interactions and functions in food, the simplicity of the models indicates that complex food system models are still needed to truly understand how to maximize the functionality of emulsifiers.
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