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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Effect of plant sterol supplementation and endurance training on cardiovascular disease risk parameters and cholesterol kinetics in previously sedentary hypercholesterolemic adults

Varady, Kristina A. January 2006 (has links)
No description available.
22

Influence of phytosterols versus phytostanols on plasma lipid levels and cholesterol metabolism in hypercholesterolemic humans

Vanstone, Catherine A. January 2001 (has links)
No description available.
23

The effects of formulation and dosing frequency of plant sterols on plasma lipid profiles and cholesterol kinetics parameters in hypercholesterolemic subjects /

AbuMweis, Suhad Sameer January 2007 (has links)
No description available.
24

Efeito do extrato hidrossolúvel de soja ou castanha-do-Brasil em ratos idosos /

Cabral, Bruna Raniel Vieira Pinto January 2019 (has links)
Orientador: Guilherme de Paula Nogueira / Resumo: O objetivo foi analisar os efeitos da suplementação do extrato hidrossolúvel de soja (EHS) ou castanha-do-Brasil nos fêmures de ratos Wistar idosos. Foram utilizados 27 ratos, com 570 dias, distribuídos em 3 grupos: grupo controle (C) (n=8) recebeu dieta padrão; grupo suplementado com extrato hidrossolúvel de soja (S) (n=9) (300 mL/dia); grupo (B) (n=10), oferecida 1 unidade de castanha-do-Brasil (±3,7g) por animal/dia. O experimento teve duração de 30 dias e ao final os ratos foram eutanasiados com 600 dias de idade. Foram analisadas: a massa corporal semanalmente (g), a ingestão de ração (g) e de água (mL) diariamente, foram feitas análises biofísicas, bioquímicas e hormonais das amostras (sangue, fêmur, gordura visceral, testículos e glândulas sexuais acessórias) colhidas no pós-morte. Os animais do grupo S e B consumiram menos ração quando comparados com o C. O grupo S consumiu menos água em relação ao controle. Em relação as concentrações dos hormônios (insulina, leptina, LH, testosterona) entre os grupos, estes não apresentaram diferença estatística significativa. Não houve diferença na densitometria e microtomografia óssea, mas a região da cabeça do fêmur dos ratos do grupo B apresentaram maior resistência (p=0,04) (B 151±15N, C 112±37N, S 137±37N). Os fêmures do grupo controle possuíram menor concentração de fosforo (p=0,03; 15±1%) comparados com os do S 16±1% e B 16±1%. Conclui-se que a ingestão de EHS não interferiu no metabolismo ósseo, mas o consumo da castanha-do... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objective was to analyze the effects of soybean or Brazil nut supplementation on the femurs of elderly Wistar rats. Twenty-seven rats with 570 days of age were used, distributed in 3 groups: control group (n=8, C) with standard diet; group S (n=9) supplemented with soy milk (300 mL/day); group B (n=10), added 1 unit of Brazil nut (± 3.7g) per animal/day. The experiment lasted for 30 days, and at the end, the rats were euthanized with 600 days of age. Were measured: body mass weekly (g); feed intake (g) and water intake (mL) daily, as well as biophysical, biochemical and hormonal analysis of postmortem samples (blood, femur, visceral fat, testicles and sexual accessories glands) were analyzed. The animals of group S and B consumed less ration when compared to group C. The group S ingested less water compared to the control. Regarding the applications of hormone concentrations (insulin, leptin, LH, testosterone) between groups, these are not relevant. There were no differences on bone densitometry and microtomography but femoral head from the group B rats presented greater shear resistance (p = 0.04; B 151 ± 15N, C 112 ± 37N, S 137 ± 37N) than the other groups. Bones from control rats had lower phosphorus concentration (p=0.03; 15±1%) compared to S 16±1% and B 16±1%. It was possible to concluded that soy milk intake did not interfere on the bone metabolism, but the Brasil nut consumption resulted in greater bone strength and phosphorus concentration on the femoral head and ... (Complete abstract click electronic access below) / Mestre
25

Desenvolvimento de lipídios estruturados obtidos a partir de gordura do leite, óleo de girassol e ésteres de fitosteróis para aplicação em spreads / Development of structured lipids obtained from milk fat, sunflower oil, and phytosterol esters for application in a tablespread

Ract, Juliana Neves Rodrigues 03 May 2006 (has links)
Durante anos, a manteiga foi muito apreciada pelo consumidor, mas por conter grande quantidade de ácidos graxos saturados e colesterol, seu consumo tem diminuído. Recentemente, a descoberta dos malefícios causados pelos ácidos graxos trans presentes nas margarinas produzidas por hidrogenação parcial aumentou o interesse por métodos alternativos de modificação de lipídios. Assim, o objetivo deste trabalho foi desenvolver um lipídio estruturado à base de gordura do leite que apresentasse maiores teores de ácidos graxos insaturados que a manteiga original e, consequentemente, melhor espalhabilidade, além de conter fitosteróis, constituindo a base de um alimento funcional com capacidade de reduzir os níveis de colesterol no sangue. Foram realizadas misturas da gordura do leite (GL) com óleo de girassol (OG) e ésteres de fitosteróis (EF) e foi efetuada interesterificação química e enzimática. As misturas e os lipídios estruturados obtidos foram analisados quanto a composição em ácidos graxos, consistência, conteúdo de gordura sólida (CGS), cinética de cristalização e estrutura cristalina, entre outras propriedades físico-químicas. Foram obtidos produtos contendo cerca de 60% de ácidos graxos insaturados pela adição de até 40% de OG e 25% de EF à gordura do leite, que originalmente possuía cerca de 33% de ácidos graxos insaturados. A interesterificação química melhorou a plasticidade das misturas, enquanto que a modificação enzimática não modificou de maneira expressiva sua consistência. A adição de pequenas quantidades de OG à GL provocou grande diminuição de sua consistência, enquanto que a diminuição do CGS ocorreu em proporções semelhantes às esperadas por interpolação linear. A edição de vídeos que permitam a observação da formação da estrutura cristalina de gorduras mostrou ser uma ferramenta de grande utilidade no estudo da cristalização de óleos e gorduras. A emulsão preparada com a mistura contendo 25,0% de EF, 7,5% de OG e 67,5% de GL apresentou diminuição expressiva na consistência quando comparada à manteiga, representando um efeito benéfico. / For many years, butter has been held in the highest esteem by consumer but its world consumption has steadily declined due to its high contents of saturated fatty acids and cholesterol. More recently, trans fatty acids, which are commonly resent in hydrogenated argarines, have been found to cause detrimental effects when consumed in high amounts. This observation has increased the interest in alternative methods of lipid modification. Therefore, the objective of this work was to develop a milkfat based structured lipid, presenting higher contents of unsaturated fatty acids than original butter and consequently better spreadability, besides containing phytosterols and serving as a base of a functional food with a cholesterol lowering health claim. Blends containing milkfat (MF), sunflower oil (SO) and phytosterol esters (PE) were prepared and then chemically and enzimatically interesterified. The fatty acid composition, consistency, solid fat content (SFC), crystallization kinetics and crystal structure, among other physical and chemical properties were analyzed. The blends presented about 60% of unsaturated fatty acids with the addition of up to 40% of SO and 25% of PE to MF, which originally presented close to 33% of unsaturated fatty acids. Chemical interesterification improved the plasticity of the blends, while the enzymatic reaction did not substantially alter it. The addition of small amounts of SO and PE to MF caused a great decrease in its consistency, while SFC decreased almost proportionally to the addition of these components. The edition of videos made possible the observation of crystal structure formation and it represented a tool of great importance in the fats and oils crystallization research. The emulsion prepared with the blend containing 25.0% of PE, 7.5% of SO, and 67.5% of MF presented a substantial improvement in consistency when compared to butter commercially available.
26

Ação dos fitoesteróis sobre lesão aterosclerótica em camundongos com ablação gênica do receptor de LDL / Phytosterols effects over atherosclerotic lesion in mice with ablation of the LDL receptor gene

Bombo, Renata de Paula Assis 13 August 2014 (has links)
Introdução: Os fitoesteróis (FE) são reconhecidos por reduzirem a concentração plasmática de LDL-colesterol, sendo importantes coadjuvantes no tratamento da hipercolesterolemia moderada. Entretanto, estudos publicados recentemente demonstram resultados conflitantes em relação à eficiência dos FE na prevenção da aterosclerose. Além disso, algumas investigações evidenciaram que o aumento da concentração plasmática de FE está positivamente relacionado ao risco de desenvolvimento de aterosclerose. Com a finalidade de elucidar a sua ação sobre esses parâmetros, o objetivo deste estudo foi avaliar os efeitos da suplementação de FE no desenvolvimento da aterosclerose em camundongos com ablação gênica para o receptor de LDL (LDLr-KO). Métodos: Os animais foram alimentados durante 16 semanas, com dieta rica em gordura (40% do valor calórico total da dieta), suplementada (grupo FE; 2%, n=10) ou não (Controle; n=10) com FE. Foram avaliadas as concentrações plasmáticas e hepáticas de colesterol, triglicérides, FE (beta-sitosterol, campesterol e latosterol). Na aorta dos animais, determinaram-se as concentrações de colesterol total, colesterol livre e éster e FE, além do infiltrado de macrófagos e infiltrado de lípides. Nos macrófagos do peritôneo dos animais, os quais assemelham-se aos presentes na artéria, avaliou-se a expressão de RNA mensageiro dos genes envolvidos no efluxo e influxo de colesterol (ABCA1, ABCG1, LOX1 e CD36). Também determinou-se as concentrações de FE no intestino e baço dos animais. Resultados: Conforme esperado, o consumo de FE induziu elevação plasmática dos principais FE, campesterol e de beta-sitosterol, reduzindo a concentração de colesterol no plasma. Houve aumento nas concentrações hepáticas de triglicérides e FE, entretanto, não foram observadas diferenças entre os grupos nas expressões de RNA mensageiro de genes lipolíticos (CPT, PPAR alfa) e lipogênicos (SREBP1-c, MTP, LXR e PPAR gamma) no fígado. Não houve, também, alteração no SREBP2, gene relacionado à síntese de colesterol. O conteúdo de colesterol total na artéria foi menor nos animais do grupo FE, não diferindo entre as formas livre e éster. As concentrações de FE na artéria foram iguais entre os grupos. A área de lesão no grupo FE foi menor em relação ao grupo-controle. A suplementação com FE induziu redução na expressão de RNA mensageiro de ABCG1, não interferindo na expressão dos outros genes estudados na artéria. Conclusão: Os achados deste estudo demonstram que a elevação de FE no plasma não induziu o seu acúmulo na parede da artéria e preveniu o desenvolvimento da aterosclerose / Introduction: The plasma cholesterol-reducing effect of hytosterols (PS) is well recognized and they are considered important adjuncts in the treatment of moderate hypercholesterolemia. However, recent studies have shown conflicting results regarding the efficiency of PS in the prevention of atherosclerosis. In addition, some studies showed that the increase in plasma PS concentration is positively correlated to the risk of atherosclerosis. In order to elucidate its action on these parameters, the objective of this study was to evaluate the effects of PS supplementation in the development of atherosclerosis in LDL receptor knock-out mice (LDLr -KO). Methods: The animals were fed during 16 weeks with high fat diet (40 % of calories as fat), supplemented (PS group, 2%, n = 10) or not (Control, n = 10) with PS. Plasma and liver concentrations of cholesterol, triglycerides, PS (beta - sitosterol, campesterol and lathosterol) were evaluated. In the aorta of the animals, the concentrations of total cholesterol, free cholesterol, cholesterol ester and PS, besides macrophage and lipids infiltration were determined. The mRNA expression of genes involved in cholesterol efflux and influx (ABCA1, ABCG1, LOX1 and CD36) were evaluated, in peritoneum macrophage, which resemble those present in the artery. It was also determined the intestine and spleen PS concentrations from the animals of both groups. Results: As expected, PS supplementation induced increasing plasma concentration of the main PS, campesterol and beta -sitosterol and reducing cholesterol plasma concentration. It was observed an increase so intestine and spleen PS concentrations. There was an increase in hepatic triglyceride concentrations and PS, however, no differences were observed between the groups of hepatic mRNA expression of lipolytic (CPT, PPARalfa) and lipogenic genes (SREBP1c, MTP, CPT, LXR, and PPAR gamma). There was no difference on SREBP2, gene related to cholesterol synthesis. The content of total cholesterol in the artery was lower in PS group animals however did not differ between the free and ester forms. Artery PS concentrations did not differ between groups. The lesion area in the PS group was lower than in the control group. PS supplementation induced reduction in mRNA expression of ABCG1, not affecting the expression of other genes studied in artery. Conclusion: The findings of this study demonstrate that the elevation of plasma PS concentration did not induce its accumulation in the arterial wall and prevented the development of atherosclerosis
27

Effects of phytosterols and phytosterol oxidation products on the vasculature.

January 2011 (has links)
Yang, Chao. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 137-146). / Abstracts in English and Chinese. / Thesis Committee --- p.i / Acknowledgements --- p.ii / Contents --- p.iii / Declaration --- p.vii / Abstract --- p.viii / 摘要 --- p.xi / Abbreviations --- p.xiii / Chapter CHAPTER ONE: --- INTRODUCTION / Chapter 1.1 --- Occurrence and Structure of Phytosterols in Plants --- p.P.1 / Chapter 1.2 --- Biological Effects of Phytosterols / Chapter 1.2.1 --- Cholesterol-lowering Effect of Phytosterols --- p.P.3 / Chapter 1.2.2 --- Anti-cancer Effect of Phytosterols --- p.P.5 / Chapter 1.2.3 --- Anti-proliferative Effect of Phytosterols --- p.P.5 / Chapter 1.3 --- Intake and Absorption of Phytosterols in Human Beings --- p.P.6 / Chapter 1.4 --- Occurrence and Physiological Levels of Phytosterol Oxidation Products (POPs) / Chapter 1.4.1 --- Occurrence of POPs --- p.P.8 / Chapter 1.4.2 --- Physiological Levels of POPs --- p.P.8 / Chapter 1.5 --- Endothelium and the Vascular Tone / Chapter 1.5.1 --- Role of Endothelium in the Control of Vascular Tone --- p.P.11 / Chapter 1.5.2 --- "Endothelial Dysfunction, Cholesterol Oxidation Products (COPs) and Phytosterol Oxidation Products (POPs)" --- p.P.12 / Chapter 1.6 --- Calcium Homeostasis in the Vascular Smooth Muscle Cells (VSMCs) / Chapter 1.6.1 --- Modes of Ca2+ Entry in VSMCs --- p.P.15 / Chapter 1.6.2 --- Modes of Ca2+ Efflux in VSMCs --- p.P.18 / Chapter 1.7 --- Objectives of the Study --- p.P.19 / Chapter CHAPTER TWO: --- β-SITOSTEROL OXIDATION PRODUCTS ATTENUATE VASORELAXATION BY INCREASING REACTIVE OXYGEN SPECIES AND CYCLOOXYGENASE-2 / Chapter 2.1 --- Introduction --- p.P.21 / Chapter 2.2 --- Materials and Methods / Chapter 2.2.1 --- Preparation of SOPs --- p.P.24 / Chapter 2.2.2 --- Gas Chromatography -mass Spectrometry (GC-MS) Identification of SOPs --- p.P.24 / Chapter 2.2.3 --- Analysis of SOPs --- p.P.25 / Chapter 2.2.4 --- Vessel Preparation --- p.P.25 / Chapter 2.2.5 --- Isometric Force Measurement --- p.P.26 / Chapter 2.2.6 --- Western Blotting --- p.P.27 / Chapter 2.2.7 --- Primary Culture of Rat Aortic Endothelial Cell --- p.P.28 / Chapter 2.2.8 --- Measurement of SOPs-induced Intracellular Oxidative Stress --- p.P.29 / Chapter 2.2.9 --- Drugs --- p.P.30 / Chapter 2.2.10 --- Data Analysis --- p.P.30 / Chapter 2.3 --- Results / Chapter 2.3.1 --- GC-MS Identification of SOPs --- p.P.32 / Chapter 2.3.2 --- Analysis of SOPs --- p.P.34 / Chapter 2.3.3 --- SOPs But Not β-Sitosterol Impaired ACh- and A23187-induced relaxations --- p.P.36 / Chapter 2.3.4 --- Inhibition of COX Pathway Reversed SOPs-induced Impairment in Relaxation --- p.P.39 / Chapter 2.3.5 --- SOPs Elevated Endothelial COX-2 Expression --- p.P.42 / Chapter 2.3.6 --- SOPs Increased COX-2 Expression via An Oxidative Stress-sensitive Pathway --- p.P.45 / Chapter 2.4 --- Discussion --- p.P.52 / Chapter 2.5 --- Conclusion --- p.P.56 / Chapter CHAPTER THREE: --- β-SITOSTEROL OXIDATION PRODUCTS POSSESS POTENTIAL VOCC BLOCKING EFFECT IN VSMCs / Chapter 3.1 --- Introduction / Chapter 3.1.1 --- 2+ Modes of Ca Entry and Efflux in Vascular Smooth Muscle Cells (VSMCs) --- p.P.57 / Chapter 3.1.2 --- Effect of Cholesterol and COPs on VSMCs --- p.P.57 / Chapter 3.2 --- Methodology and Materials / Chapter 3.2.1 --- Vessel Preparation --- p.P.59 / Chapter 3.2.2 --- Isometric Force Measurement iv --- p.P.59 / Chapter 3.2.3 --- Drugs --- p.P.60 / Chapter 3.2.4 --- Data Analysis --- p.P.61 / Chapter 3.3 --- Results / Chapter 3.3.1 --- SOPs but not β-Sitosterol Induced Relaxation in 60 mM K+ -preconstricted Endothelium-denuded Aorta --- p.P.62 / Chapter 3.3.2 --- Both SOPs and β-Sitosterol did not Relax U46619-preconstricted Endothelium-denuded Aorta --- p.P.64 / Chapter 3.3.3 --- Both SOPs and β-Sitosterol did not Relax PDA -preconstricted Endothelium-denuded Aorta --- p.P.66 / Chapter 3.3.4 --- SOPs Attenuated 60 mM K+-induced Contraction --- p.P.68 / Chapter 3.3.5 --- SOPs Attenuated Phenylephrine-induced Contraction --- p.P.70 / Chapter 3.3.6 --- Effect of SOPs on Concentration-dependent Responses to U46619 --- p.P.72 / Chapter 3.3.7 --- Preincubation with Bay K 8644 Abolished SOPs-induced Relaxation in 60 mM K+ -preconstricted Rings --- p.P.74 / Chapter 3.3.8 --- Preincubation with Thapsigargin did not Affect SOPs-induced Relaxation in 60 mM K+ -preconstricted Rings --- p.P.76 / Chapter 3.3.9 --- Preincubation with Ouabain did not Affect SOPs-induced Relaxation in 60 mM K+ -preconstricted Rings --- p.P.78 / Chapter 3.3.10 --- Preincubation with Nickel Potentiated SOPs-induced Relaxation in 60 mM K+ -preconstricted Rings --- p.P.80 / Chapter 3.4 --- Discussion --- p.P.84 / Chapter 3.5 --- Conclusion and Future Work --- p.P.88 / Chapter CHAPTER FOUR: --- INVOLEMENT OF NITRIC OXIDE IN THE PROTECTIVE EFFECTS OF PHYTOSTEROLS AGAINST HOMOCYSTEINE-INDUCED IMPAIRMENT OF ENDOTHELIUM-DEPENDENT RELAXATIONS OF RAT AORTA / Chapter 4.1 --- Introduction --- p.P.89 / Chapter 4.2 --- Materials and Method / Chapter 4.2.1 --- Vessel Preparation --- p.P.93 / Chapter 4.2.2 --- Isometric Force Measurement --- p.P.93 / Chapter 4.2.3 --- Western Blotting --- p.P.94 / Chapter 4.2.4 --- "1,1 -diphenyl-2-picrylhydrazyl (DPPH) Radical Scavenging Capacity" --- p.P.96 / Chapter 4.2.5 --- Primary Culture of Rat Aortic Endothelial Cells V --- p.P.96 / Chapter 4.2.6 --- Measurement Intracellular Oxidative Stress --- p.P.97 / Chapter 4.2.7 --- Nitric Oxide (NO) Measurement --- p.P.97 / Chapter 4.2.8 --- Drugs --- p.P.98 / Chapter 4.2.9 --- Data Analysis --- p.P.99 / Chapter 4.3 --- Results / Chapter 4.3.1 --- Impairment of Endothelium-dependent Relaxation by HC was Reversed by ROS Scavenger --- p.P.100 / Chapter 4.3.2 --- Brassicasterol Reversed HC-induced Endothelial Dysfunction In a Dose-dependent Manner --- p.P.102 / Chapter 4.3.3 --- β-Sitosterol and Stigmasterol Reversed HC-induced Endothelial Dysfunction --- p.P.104 / Chapter 4.3.4 --- Effects of β-Sitosterol Oxidation Products (SOPs) on HC-induced Endothelial Dysfunction --- p.P.106 / Chapter 4.3.5 --- Effects of Brassicasterol and β-Sitosterol on H2O2-induced Impairment of Endothelium-dependent Relaxation --- p.P.108 / Chapter 4.3.6 --- Phytosterols did not Directly Scavenge Free Radicals --- p.P.110 / Chapter 4.3.7 --- "HC and Brassicasterol did not Affect the Expression of SOD-1, SOD-2, eNOS, COX-1 and COX-2 in Aorta" --- p.P.112 / Chapter 4.3.8 --- HC Increased ROS Production in Primary Rat Aortic Endotelial Cells --- p.P.116 / Chapter 4.3.9 --- Brassicasterol did not Reverse the ROS Production by HC treatment In the Endothelial Cells --- p.P.120 / Chapter 4.3.10 --- Effect of L-NAME on Reversing the Effect of Brassicasterol on ACh-induced Relaxation --- p.P.123 / Chapter 4.3.11 --- Brassicasterol Reversed the Inhibitory Effect of HC on ACh-induced NO Production in Endothelial Cells --- p.P.125 / Chapter 4.4 --- Discussion --- p.P.128 / Chapter 4.5 --- Conclusion and Future Work --- p.P.132 / Chapter CHAPTER FIVE: --- CONCLUSIONS AND FUTURE WORK --- p.P.134 / Chapter CHAPTER SIX: --- REFERENCES --- p.P.137
28

Desenvolvimento de lipídios estruturados obtidos a partir de gordura do leite, óleo de girassol e ésteres de fitosteróis para aplicação em spreads / Development of structured lipids obtained from milk fat, sunflower oil, and phytosterol esters for application in a tablespread

Juliana Neves Rodrigues Ract 03 May 2006 (has links)
Durante anos, a manteiga foi muito apreciada pelo consumidor, mas por conter grande quantidade de ácidos graxos saturados e colesterol, seu consumo tem diminuído. Recentemente, a descoberta dos malefícios causados pelos ácidos graxos trans presentes nas margarinas produzidas por hidrogenação parcial aumentou o interesse por métodos alternativos de modificação de lipídios. Assim, o objetivo deste trabalho foi desenvolver um lipídio estruturado à base de gordura do leite que apresentasse maiores teores de ácidos graxos insaturados que a manteiga original e, consequentemente, melhor espalhabilidade, além de conter fitosteróis, constituindo a base de um alimento funcional com capacidade de reduzir os níveis de colesterol no sangue. Foram realizadas misturas da gordura do leite (GL) com óleo de girassol (OG) e ésteres de fitosteróis (EF) e foi efetuada interesterificação química e enzimática. As misturas e os lipídios estruturados obtidos foram analisados quanto a composição em ácidos graxos, consistência, conteúdo de gordura sólida (CGS), cinética de cristalização e estrutura cristalina, entre outras propriedades físico-químicas. Foram obtidos produtos contendo cerca de 60% de ácidos graxos insaturados pela adição de até 40% de OG e 25% de EF à gordura do leite, que originalmente possuía cerca de 33% de ácidos graxos insaturados. A interesterificação química melhorou a plasticidade das misturas, enquanto que a modificação enzimática não modificou de maneira expressiva sua consistência. A adição de pequenas quantidades de OG à GL provocou grande diminuição de sua consistência, enquanto que a diminuição do CGS ocorreu em proporções semelhantes às esperadas por interpolação linear. A edição de vídeos que permitam a observação da formação da estrutura cristalina de gorduras mostrou ser uma ferramenta de grande utilidade no estudo da cristalização de óleos e gorduras. A emulsão preparada com a mistura contendo 25,0% de EF, 7,5% de OG e 67,5% de GL apresentou diminuição expressiva na consistência quando comparada à manteiga, representando um efeito benéfico. / For many years, butter has been held in the highest esteem by consumer but its world consumption has steadily declined due to its high contents of saturated fatty acids and cholesterol. More recently, trans fatty acids, which are commonly resent in hydrogenated argarines, have been found to cause detrimental effects when consumed in high amounts. This observation has increased the interest in alternative methods of lipid modification. Therefore, the objective of this work was to develop a milkfat based structured lipid, presenting higher contents of unsaturated fatty acids than original butter and consequently better spreadability, besides containing phytosterols and serving as a base of a functional food with a cholesterol lowering health claim. Blends containing milkfat (MF), sunflower oil (SO) and phytosterol esters (PE) were prepared and then chemically and enzimatically interesterified. The fatty acid composition, consistency, solid fat content (SFC), crystallization kinetics and crystal structure, among other physical and chemical properties were analyzed. The blends presented about 60% of unsaturated fatty acids with the addition of up to 40% of SO and 25% of PE to MF, which originally presented close to 33% of unsaturated fatty acids. Chemical interesterification improved the plasticity of the blends, while the enzymatic reaction did not substantially alter it. The addition of small amounts of SO and PE to MF caused a great decrease in its consistency, while SFC decreased almost proportionally to the addition of these components. The edition of videos made possible the observation of crystal structure formation and it represented a tool of great importance in the fats and oils crystallization research. The emulsion prepared with the blend containing 25.0% of PE, 7.5% of SO, and 67.5% of MF presented a substantial improvement in consistency when compared to butter commercially available.
29

Effects of plant sterols on plasma lipid profiles, glycemic control of hypercholesterolemic individuals with and without type 2 diabetes

Lau, Vivian Wai Yan, 1977- January 2003 (has links)
Plant sterols (PS) are effective in reducing plasma lipid concentrations, however, few studies have examined their cholesterol lowering effects in type 2 diabetics. The objective was to assess whether PS consumption alters blood lipid profile in hypercholesterolemic subjects with and without type 2 diabetes. Fifteen control subjects (age = 55.1 +/- 8.5 yr and BMI = 26.9 +/- 3.0kg/m2) and fourteen diabetic subjects (age = 54.5 +/- 6.7 yr and BMI = 30.2 +/- 3.0kg/m2) participated in a double-blinded, randomized, crossover, placebo-controlled feeding trial. The Western diet included either 1.8g/d of PS or cornstarch placebo each provided over 21 d separated by a 28 d washout period. Subjects consumed only foods prepared in Mary Emily Clinical Nutrition Research Unit of McGill University. Total cholesterol (TC) decreased (p < 0.05) from baseline with PS for control and diabetic subjects by 9.7% and 13.6%, respectively. TC decreased (P < 0.05) from baseline with placebo for control and diabetic subjects by 10.9% and 11.6%, respectively. Non high density lipoprotein cholesterol (non-HDL-C) decreased (p < 0.05) from baseline with PS for diabetic subjects by 18.5%. Low density lipoprotein cholesterol (LDL-C) levels were reduced (p < 0.05) from baseline with PS for control and diabetic subjects by 14.9% and 29.8%, respectively. The reduction of LDL-C due to PS alone is greater with type 2 diabetics. There were no significant changes in HDL-C and TG across diets or treatments. It is thus concluded that PS consumption with diet enhances non-HDL-C and LDL-C reduction compared with diet alone in hypercholesterolemic individuals with and without type 2 diabetes. Demonstration for the first time that PS alone are more efficacious in lowering LDL-C and non-HDL-C in diabetic individuals compared to non-diabetics confirm the beneficial effects of PS to help prevent cardiovascular disease (CVD) for this high risk population.
30

Plant sterols and glucomannan as hypocholesterolemic and hypoglycemic agents in subjects with and without type 2 diabetes

Yoshida, Makiko January 2003 (has links)
The objective of this research was to examine the effects of plant sterols and glucomannan on lipid profiles, plasma plant sterol levels and glycemic control in mildly hypercholesterolemic subjects. Thirteen type 2 diabetic and sixteen non-diabetic individuals participated in a randomized crossover trial consisting of 4 phases, of 21 days each. During the study period, subjects were supplemented with plant sterols and/or glucomannan. Overall reductions of total cholesterol and low-density lipoprotein (LDL) cholesterol concentrations were greater after consumption of plant sterols and glucomannan compared to plant sterol or glucomannan supplementation alone. Plasma lathosterol levels, indicators of cholesterol biosynthesis, were decreased after combination treatment. The results suggest that a combination of glucomannan and plant sterols substantially improve plasma lipids by reducing cholesterol absorption and synthesis simultaneously. Supplementation of plant sterols and glucomannan can thus be used as an effective treatment for management of circulating cholesterol levels and prevention of cardiovascular disease.

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