Oils' Impact on Comprehensive Fatty Acid Analysis and Their Metabolites in Rats.

Fatty acids, especially polyunsaturated, and their metabolites (eicosanoids) play many pivotal roles in human body, influencing various physiological and pathological processes. The aim of the study was to evaluate the effect of supplementation with edible oils diverse in terms of fatty acid composition on fatty acid contents, activities of converting their enzymes, and on lipoxygenase metabolites of arachidonic and linoleic acids (eicosanoids) in rat serum. Female Sprague-Dawley rats divided into seven groups were used in the study. Animals from six groups were fed one of oils daily (carotino oil, made up by combining of red palm oil and canola oil, linseed oil, olive oil, rice oil, sesame oil, or sunflower oil). One group received a standard diet only. Fatty acids were determined using gas chromatography with flame ionization detection. Eicosanoids-hydroxyeicosatetraenoic (HETE) and hydroxyoctadecadienoic acids (HODE) were extracted using a solid-phase extraction method and analyzed with HPLC. Vegetable oils given daily to rats caused significant changes in serum fatty acid profile and eicosanoid concentrations. Significant differences were also found in desaturases' activity, with the linseed and olive oil supplemented groups characterized by the highest D6D and D5D activity. These findings may play a significant role in various pathological states.

Effects of high-fiber diets enriched with carbohydrate, protein, or unsaturated fat on circulating short chain fatty acids: results from the OmniHeart randomized trial.

BACKGROUND: Short chain fatty acids (SCFAs; e.g., acetate, propionate, and butyrate) are produced by microbial fermentation of fiber in the colon. Evidence is lacking on how high-fiber diets that differ in macronutrient composition affect circulating SCFAs. OBJECTIVES: We aimed to compare the effects of 3 high-fiber isocaloric diets differing in %kcal of carbohydrate, protein, or unsaturated fat on circulating SCFAs. Based on previous literature, we hypothesized that serum acetate, the main SCFA in circulation, increases on all high-fiber diets, but differently by macronutrient composition of the diet. METHODS: OmniHeart is a randomized crossover trial of 164 men and women (≥30 y old); 163 participants with SCFA data were included in this analysis. We provided participants 3 isocaloric high-fiber (∼30 g/2100 kcal) diets, each for 6 wk, in random order: a carbohydrate-rich (Carb) diet, a protein-rich (Prot) diet (protein predominantly from plant sources), and an unsaturated fat-rich (Unsat) diet. We used LC-MS to quantify SCFA concentrations in fasting serum, collected at baseline and the end of each diet period. We fitted linear regression models with generalized estimating equations to examine change in ln-transformed SCFAs from baseline to the end of each diet; differences between diets; and associations of changes in SCFAs with cardiometabolic parameters. RESULTS: From baseline, serum acetate concentrations were increased by the Prot (ß: 0.24; 95% CI: 0.12, 0.35), Unsat (ß: 0.21; 95% CI: 0.10, 0.33), and Carb (ß: 0.12; 95% CI: 0.01, 0.24) diets; between diets, only Prot compared with Carb was significant (P = 0.02). Propionate was decreased by the Carb (ß: -0.10; 95% CI: -0.16, -0.03) and Unsat (ß: -0.10; 95% CI: -0.16, -0.04) diets, not the Prot diet; between diet comparisons of Carb vs. Prot (P = 0.006) and Unsat vs. Prot (P = 0.002) were significant. The Prot diet increased butyrate (ß: 0.05; 95% CI: 0.00, 0.09) compared with baseline, but not compared with the other diets. Increases in acetate were associated with decreases in insulin and glucose; increases in propionate with increases in leptin, LDL cholesterol, and blood pressure; and increases in butyrate with increases in insulin and glucose, and decreases in HDL cholesterol and ghrelin (Ps < 0.05). CONCLUSIONS: Macronutrient composition of high-fiber diets affects circulating SCFAs, which are associated with measures of appetite and cardiometabolic health. This trial was registered at clinicaltrials.gov as NCT00051350.

Process simulation and techno economic analysis of renewable diesel production via catalytic decarboxylation of rubber seed oil - A case study in Malaysia.

This work describes the economic feasibility of hydroprocessed diesel fuel production via catalytic decarboxylation of rubber seed oil in Malaysia. A comprehensive techno-economic assessment is developed using Aspen HYSYS V8.0 software for process modelling and economic cost estimates. The profitability profile and minimum fuels selling price of this synthetic fuels production using rubber seed oil as biomass feedstock are assessed under a set of assumptions for what can be plausibly be achieved in 10-years framework. In this study, renewable diesel processing facility is modelled to be capable of processing 65,000 L of inedible oil per day and producing a total of 20 million litre of renewable diesel product per annual with assumed annual operational days of 347. With the forecasted renewable diesel retail price of 3.64 RM per kg, the pioneering renewable diesel project investment offers an assuring return of investment of 12.1% and net return as high as 1.35 million RM. Sensitivity analysis conducted showed that renewable diesel production cost is most sensitive to rubber seed oil price and hydrogen gas price, reflecting on the relative importance of feedstock prices in the overall profitability profile.

Antioxidant activity of alkyl hydroxytyrosyl ethers in unsaturated lipids.

The antioxidant activity of ethyl and octyl hydroxytyrosyl ethers toward lipids was determined using the Rancimat and open cup methods at high temperatures and 50 °C, respectively. The effect of the unsaturation of the matrix was evaluated using sunflower, soya, and fish refined oils. The antioxidant activities of alkyl hydroxytyrosyl ethers (HTy ethers), hydroxytyrosyl esters, and free hydroxytyrosol are similar, and are much higher than that of α-tocopherol at the same millimolar concentration. The relationship between the induction period and the concentration of the HTy ethers is a sigmoidal curve; an accurate concentration of HTy ethers is necessary to achieve maximum activity, as it increases with the level of matrix unsaturation. The presence of tocopherols in commercial oils affects the antioxidant effect of HTy ethers. Thus, the addition of a low concentration of HTy ethers results in a positive effect, whereas the effect of the addition of high amounts of ethers is slightly less than that of the phenol alone. The addition of HTy ethers to commercial refined oils increases the stability of the oils and preserves tocopherols and polyunsaturated fatty acids from oxidation, enabling the oils to maintain their nutritional properties for longer periods of time.

Silver dopants for targeted and untargeted direct analysis of unsaturated lipids via infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI).

RATIONALE: Unsaturated lipids play a crucial role in cellular processes as signaling factors, membrane building blocks or energy storage molecules. However, adequate mass spectrometry imaging of this diverse group of molecules remains challenging. In this study we implemented silver cationization for direct analysis by infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI) to enhance the ion abundances for olefinic lipids and facilitate peak assignment. METHODS: Trace amounts of silver nitrate were doped into the electrospray solvent of an IR-MALDESI imaging source coupled to an Orbitrap mass analyzer. Calcifediol was examined as a model compound to demonstrate the effect of silver dopants on sensitivity and assay robustness. Dried human serum spots were subsequently analyzed to compare Ag-doped solvents with previously described solvent compositions. Mass differences as well as ion abundance ratio filters were employed to interpret results based on the characteristic isotopic pattern of silver. RESULTS: Olefinic lipids were readily observed as silver adducts in IR-MALDESI analyses. Silver cationization decreased the limit of detection for calcifediol by at least one order of magnitude and was not affected in complex biological matrices. The ion abundance ratio and mass difference of [M + (107) Ag(+)](+) and [M + (109) Ag(+)](+) were successfully applied to facilitate the spectral assignment of silver adducts. Overall, silver cationization increased the analyte coverage in human serum by 43% compared with a standard IR-MALDESI approach. CONCLUSIONS: Silver cationization has been shown to enhance IR-MALDESI sensitivity and selectivity for unsaturated lipids, even when applied to complex samples. Increased compound coverage, enhanced robustness as well as the developed tools for peak assignment and mapping of isotopic patterns will clearly benefit future mass spectrometry imaging studies.

Relación entre la calidad de la grasa ingerida en el desayuno y el riesgo cardiovascular. Revisión / Relationship between quality of fat consumed at breakfast and cardiovascular risk. Review

Introducción: Existe evidencia científica que relaciona el hábito del desayuno regular con una disminución del riesgo cardiovascular por disminuir la grasa corporal. Sin embargo existe incertidumbre sobre si el tipo de grasa consumida en el desayuno influye sobre el perfil lipidico y de ese modo sobre el riesgo cardiovascular. Objetivo: Mostrar una perspectiva tras analizar la evidencia científica publicada sobre el efecto que el tipo de grasa ingerida en el desayuno ejerce sobre el riesgo cardiovascular en el ser humano. Este tipo de estudio se plantea como un instrumento para sugerir directrices y recomendaciones en políticas sanitarias dentro del ámbito de la nutrición humana. Método: Se realizó la revisión empleando las bases de datos de las revistas con fecha de publicación entre 2000 y 2014, utilizando criterios de inclusión específicos (estudios con seres humanos). Resultado: Las evidencias bibliográficas afirman que en las diferentes etapas de la vida del ser humano, los individuos que desayunan regularmente tienen un menor contenido de grasa corporal. Los resultados también muestran que el consumo regular del desayuno con grasas insaturadas está asociado con un perfil cardiovascular saludable, y que este hábito saludable puede anular en parte el efecto del exceso de adiposidad en colesterol total y LDL-C. Conclusión: El consumo regular en el desayuno de grasas insaturadas (poli y monoinsaturadas) mejora el perfil lipídico, disminuyendo el riesgo cardiovascular, por lo que estas grasas poli y monoinsaturadas se deben recomendar como parte del desayuno habitual de una dieta saludable (AU)

Introduction: There is scientific evidence linking regular breakfast habit with decreased cardiovascular risk by lowering body fat. However, there is uncertainty about whether the type of fat consumed at breakfast influences the lipid profile and so on cardiovascular risk. Objective: To show a perspective after analyzing the published scientific evidence on the effect that the type of fat eaten at breakfast exerts on cardiovascular risk in humans. This type of study is proposed as a tool to suggest guidelines and recommendations on health policy in the field of human nutrition. Method: The review was conducted using the databases of journals published between 2000 and 2014, using specific inclusion criteria (human studies). Result: The bibliographical evidences say that at different stages of human life, individuals who regularly eat breakfast have a lower body fat content. The results also show that regular consumption of breakfast with unsaturated fats is associated with a healthier cardiovascular profile, and that this healthy habit can override some of the effects of excess adiposity in total cholesterol and LDLc. Conclusion: Regular breakfast consumption of unsaturated fats (poly and monounsaturated) improves the lipid profile, reducing cardiovascular risk, so these poly and monounsaturated fats should be recommended as part of the usual breakfast of a healthy diet (AU)

Direct determination of unsaturation level of milk fat using Raman spectroscopy.

We have demonstrated the potential of visible Raman spectroscopy in combination with chemometric analysis as a fast and simple tool for the determination of the unsaturation level of milk fat. The Raman measurements have been performed directly on liquid milk and on fat extracted from liquid milk. The Raman spectra taken from the extracted fat showed a higher resolution. The spectra directly obtained from the milk samples had some fluorescence background but nevertheless yielded the desired information. For calibration purposes, the iodine value (IV) was determined in all cases in order to evaluate the unsaturation level of the investigated samples. Two separate calibration models have been constructed; one for the milk samples and the second one for the extracted fat. The accuracy of these calibration models was estimated using the root mean square error of calibration and validation (RMSE) and the coefficient of determination (R(2)) between actual and predicted values.

Diferenças estruturais e qualitativas dos óleos de oliva, girassol e linhaça e seus efeitos sobre as doenças cardiovasculares / Structure and qualitative differences in the olive, sunflower and flaxseed oils and their effects on cardiovasculare disease

A qualidade dos lípides na alimentação é um dos principaisfundamentos na prevenção e mortalidade por doenças crônicasnão transmissíveis. Ensaios anteriores já estabeleceramos benefícios das gorduras insaturadas ante as saturadas,principalmente em relação ao ômega 3 (w-3). Mais recentemente,os estudos têm buscado avaliar os efeitos metabólicosde diversos óleos, tanto de forma isolada como associados.Como parte da dieta Mediterrânea, o óleo de oliva pareceexercer papel efetivo na diminuição plasmática de colesterol,especialmente na lipoproteína de baixa densidade (LDL). Entreos óleos ricos em ácidos polinsaturados, o de girassol e o delinhaça estão sendo analisados quanto às suas ações e sobre anecessidade de se estabelecer uma relação de consumo. Esteartigo revisa os conceitos da estrutura química dos óleos deoliva, girassol e linhaça e os efeitos que exercem sobre a saúdecardiovascular.

The importance of lipids in our nutrition is a major corner stone in the prevention and mortality from chronic diseases, both in their quantity, and quality. Previous trials have already establishedthe benefits of unsaturated fats compared to saturated, especially in relation to omega 3 (w-3). More recently, several studies try to evaluate the metabolic effects of different oils,either alone or associated. As part of the Mediterranean diet, olive oil seems to play an effective role in reducing plasmacholesterol, especially in low-density lipoprotein (LDL). Among the oils rich in polyunsaturated acids, the sunflowerand flax seed oils are being analyzed for their actions and the need to establish a consumer relationship. This article reviews the concept of the chemical structure of olive oil, sunflower oil and flaxseed oil, and their effects on cardiovascular health.

Elaboração de um sistema de pontos para intervenções dietéticas em indivíduos hiperlipidêmicos / Preparations a scoring system for dietetic interventions in hyperlipidemic individuals

Fundamentos: Sabe-se da existência de substâncias dietéticas aterogênicas e promotoras de doenças cardiovasculares. Assim a utilização de um guia de fácil compreensão e manejo poderia auxiliar na escolha de alimentos saudáveis. Objetivo: Elaborar um instrumento de orientação alimentar como ferramenta para intervenção dietética em indivíduos com hiperlipidemias. Métodos: Foi elaborado um sistema de pontos com alimentos em medidas caseiras, considerando-se as características socioculturais da população. Criou-se uma listagem de alimentos que receberam pontuações para índicede colesterol/gordura saturada (CSI). O CSI foi calculado por meio de metodologia validada, utilizando a seguinte fórmula: CSI=(1,01xg de gordura saturada) + (0,05xmg decolesterol). Um índice baixo significa alta capacidade de redução das hiperlipidemias. A necessidade individual de gorduras e colesterol para o cálculo do CSI foi extraída das recomendações da American Heart Association. Resultados: Foi organizada uma dieta de pontos para colesterol em formato de cartilha acompanhada de material explicativo. Utilizou-se como representação gráfica o Guiada Pirâmide Alimentar Saudável, pois reflete rapidamente conceitos alimentares importantes, porém em formato decoração em alusão à prevenção de doenças cardiovasculares. Conclusão: Elaborou-se, com sucesso, um instrumento de orientação alimentar denominado Sistema de Pontos para Controle de Colesterol e Gordura no Sangue. É uma ferramenta que pode apoiar a capacitação de profissionais promotores da saúde, para orientar pacientes e a população em geral.

Background: The existence of foods containing atherogenic substances that cause cardiovascular diseases is well known. An eating guide that is easy tohandle and understand could thus help patients choose healthier foods.Objective: To prepare an eating guide as a tool for dietetic intervention in hyperlipidemic individuals. Methods: A food scoring system was drawn up,assigning points to foods using ordinary home measurements, considering the social and cultural characteristics of the population. A list of foods was prepared, assigning points based on the Cholesterol / Saturated Fat Index (CSI). This Index was calculatedthrough a validated methodology based on the following formula: CSI=(1.01xg saturated fat) + (0.05xmg of cholesterol). A low score indicates goodcapacity for reducing hyperlipidemias. The individual fat and cholesterol requirements for calculating thisIndex are drawn from the American Heart Association recommendations. Results: A cholesterol score diet was designed and presented in a leaflet, together with explanatory materials,using the Healthy Food Guide Pyramid as this clearly demonstrates important food-related concepts, but reshaped into a heart in order to underscore its importance for preventing cardiovascular diseases. Conclusion: A successful eating guide was prepared,using a points system to score cholesterol and fat in the blood. This tool can provide input for trainingprofessional health promoters, as well as offering guidance to patients and the population in general.

Chemistry of deep-fat frying oils.

Deep-fat frying produces desirable or undesirable flavor compounds and changes the flavor stability and quality of the oil by hydrolysis, oxidation, and polymerization. Tocopherols, essential amino acids, and fatty acids in foods are degraded during deep-fat frying. The reactions in deep-fat frying depend on factors such as replenishment of fresh oil, frying conditions, original quality of frying oil, food materials, type of fryer, antioxidants, and oxygen concentration. High frying temperature, the number of fryings, the contents of free fatty acids, polyvalent metals, and unsaturated fatty acids of oil decrease the oxidative stability and flavor quality of oil. Antioxidant decreases the frying oil oxidation, but the effectiveness of antioxidant decreases with high frying temperature. Lignan compounds in sesame oil are effective antioxidants in deep-fat frying.

Estudio comparativo de la composición en ácidos grasos de diversos alimentos cocinados de forma casera y otros tratados industrialmente / No disponible

Se realiza un estudio del porcentaje de grasa de diversos alimentos cocinados de forma casera(en un establecimiento comercial) y otros, que forman parte de la denominada “comida rápida” ,y por tanto tratados industrialmente. La proporción de este último tipo de alimentos ha aumentado considerablemente en la dieta actual, especialmente de los jóvenes. Se realiza a de más la determinación de su proporción de ácidos grasos, observándose que las muestras presentan una composición lipídica formada en su mayoría por ácidos grasos saturados (25-54%) y monoinsaturados (26-62%). Los ácidos grasos poliinsaturados tienen valores muy heterogéneos desde un 3,5% en hamburguesas hasta 45% en croquetas. No se han detectado porcentajes importantes de ácidos grasos trans. Sin embargo, estos resultados abundan en la idea de que debería especificarse el tipo de grasa exacta utilizada en la elaboración de los alimentos (AU)

The fat compositions of several precooked traditional type foods (sold in supermarkets) were compared to those of the more processed “fast foods”. The consumption of fast food has recently increased tremendously in Spain, especially among young people. Fatty acid determinations revealed that the lipid contents of the samples mainly included saturated (25-54%)and monounsaturated (26-62%) fatty acids. Polyunsaturated fatty acids showed highly heterogeneous values ranging from 3.5% in hamburgers to 45% in Spanish croquettes (essentially containing béchamel sauce, meat and breadcrumbs).Proportions of trans fatty acids were insignificant. Our findings highlight the need to clearly specify the exact type of fat used to manufacture each product (AU)

Effects of lipid chain length and unsaturation on bicelles stability. A phosphorus NMR study.

Most studies reported until now on the magnetically alignable system formed by the binary mixtures of long- and short-chain lipids were based on the mixture of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (D14PC) and 1,2-dihexanoyl-sn-glycero-3-phosphocholine (D6PC) lipids. We have recently shown that a large part of the phase diagrams of this lipid mixture could be understood by taking into account the partial miscibility between the long-chain lipids and the short-chain lipids when the sample was heated above the melting transition temperature (Tm) of the long-chain lipids. In this work, we show by modifying the chain length of either one of the two lipids that it is possible to control their miscibility and thus the intervals of temperature and composition where spontaneous alignment is observed in a magnetic field. By using 31P NMR, we demonstrate that the very special properties of such binary lipid mixtures are correlated with the propensity for short-chain lipids to diffuse into the bilayer regions. We also show that lipid mixtures with comparable properties can be formed with unsaturated lipids such as 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC).

Efecto de la alimentación mediterránea en la respuesta lipémica posprandial / Effect of the Mediterranean diet on postprandial lipemic response

Introducción. La variabilidad individual de la respuesta lipémica posprandial excede a la que se produce en la lipemia del ayuno, debido a la influencia de factores ambientales y genéticos. Uno de los factores ambientales más relevantes es el tipo de alimentación habitual de las personas. El consumo de dietas ricas en grasa saturada favorece un mayor aumento de partículas ricas en triglicéridos posprandiales que con el consumo de dietas muy pobres en grasa y de dietas ricas en grasa poliinsaturada n-3. Sin embargo, son pocos los estudios que investiguen el efecto de la grasa monoinsaturada sobre los valores de lípidos plasmáticos en estado posprandial. Por consiguiente, nuestro objetivo fue analizar el efecto agudo de la ingesta de distintos tipos de grasa sobre la lipemia posprandial. Sujetos y métodos. La población a estudiar consistió en 21 voluntarios varones jóvenes sanos y con una edad media de 23 años a los que se sometieron a 3 sobrecargas grasas con vitamina A. La composición de la sobrecarga grasa fue de 1 g de grasa/kg de peso (el 65% grasa) con diferente composición grasa y siguiendo un protocolo aleatorizado y cruzado. La composición de las 3 sobrecargas grasas fue la siguiente: comida rica en ácidos grasos monoinsaturados procedente del aceite de oliva (un 22% de grasas saturadas, un 38% de ácidos grasos monoinsaturados, un 4% de ácidos grasos poliinsaturados y un 0,7% de ácido alfa-linolénico); comida rica en grasa saturada (un 38% de grasas saturadas, un 22% de ácidos grasos monoinsaturados, un 4% de ácidos grasos poliinsaturados y un 0,7% de ácido alfa-linolénico), y por último, una comida rica en ácidos grasos poliinsaturados n-3 de origen vegetal (un 20% de grasas saturadas, un 24% de ácidos grasos monoinsaturados, un 16% de ácidos grasos poliinsaturados y un 4% de ácido alfa-linolénico). Se extrajo sangre venosa en el tiempo 0 y a las 2, 4, 6 y 8,5 h. Se determinaron los valores plasmáticos de triglicéridos, colesterol total, lipoproteínas de alta densidad, lipoproteínas de baja densidad y apolipoproteínas A-I y B. Resultados. Se observó una mayor concentración de triglicéridos en el tiempo 2, con la comida rica en aceite de oliva que con las grasas saturada y poliinsaturada, rica en nueces. En el tiempo 8 se encontró una menor concentración de triglicéridos tras la sobrecarga rica en aceite de oliva comparada con la rica en nueces. No hubo cambios para el resto de partículas lipídicas estudiadas. Conclusión. Las personas mostraron una cinética de aclaramiento distinta en los valores de triglicéridos posprandiales tras la comida rica en aceite de oliva en comparación con la comida rica en grasa saturada y poliinsaturada n-3 (AU)

Introduction. Because of environmental and genetic factors, individual variability in postprandial lipemic response is greater than that produced in fasting lipemia. One of the most important environmental factors is the individual's normal diet. Diets rich in saturated fatty acids (SAFA) favor a greater increase in postprandial triglyceride (TG)-rich particles than low-fat diets and those rich in polyunsaturated N-3 fatty acids (PUFA). However, few studies have investigated the effect of monounsaturated fatty acids (MUFA) on plasma lipid levels in the postprandial state. Consequently, the aim of this study was to analyze the acute effect of intake of distinct types of fat on postprandial lipemia. Subjects and methods. Twenty-one healthy male volunteers with a mean age of 23 years underwent three vitamin A-fat load tests consisting of 1 g of fat/kg body weight (65% fat) with distinct fat compositions, following a randomized, crossover protocol. The composition of the diets was: high-MUFA diet from olive oil (22% SAFA, 38%; MUFA, 4%; PUFA, 0.7%; alpha-linolenic acid); high-SAFA diet (38% SAFA; 22% MUFA, 4% PUFA, 0.7% alpha-linolenic acid); PUFA-rich diet from vegetable fats (20% SAFA, 24% MUFA, 16% PUFA, 4% alpha-linolenic acid). Blood samples were taken at 0, 2, 4, 6, and 8.5 hours.. Plasma TG, total cholesterol, high-density lipoprotein (HDL)-cholesterol, low-density lipoprotein (LDL)-cholesterol, apolipoprotein (Apo) A-I and Apo B were determined. Results. TG concentration was greater at 2 hours the after intake of food rich in olive oil than after the intake of saturated and polyunsaturated fats, rich in nuts. At 8 hours, TG concentration was lower after the intake of food rich in olive oil than after the intake of polyunsaturated fat, rich in nuts. No changes in total cholesterol, HDL, LDL, Apo A-I or Apo B were observed. Conclusion. The kinetics of TG clearance differed after the monounsaturated fat load test compared with polyunsaturated N-3 and saturated fat loads (AU)

Analysis of unsaturated compounds by Ag+ coordination ionspray mass spectrometry: studies of the formation of the Ag+/lipid complex.

Coordination ionspray mass spectrometry (CIS-MS) is a useful tool in the detection and identification of cholesterol ester and phospholipid hydroperoxides and diacyl peroxides. Extensive studies of a series of cholesterol esters using CIS-MS revealed the following: (1) Cholesterol esters with equal number of double bonds as the internal standard showed a linear relative response in the mass spectrometer while compounds with non-equal numbers of double bonds gave a nonlinear relative response. (2) Complex adducts containing cholesterol ester, silver ion, AgF, AgBF(4), and 2-propanoxide form when silver is in molar excess of cholesterol esters, reducing the [M + Ag](+) signal. (3) In a mixture of cholesterol esters where silver is limiting, Ch22:6 and Ch20:4 bind to silver at the expense of Ch18:2 and have a higher signal in the mass spectrometer. (4) In a mixture of cholesterol esters where silver concentration is twofold greater than total cholesterol ester concentration, Ch22:6 and Ch20:4 form large complex adducts more frequently than Ch18:2 and have a lower signal in the mass spectrometer.

[Physico-chemical characteristics of different types of vegetable fats and oils used in the manufacture of candies]. / Características físico-químicas de diferentes tipos de grasas y aceites vegetales utilizados en la elaboración de bombones.

The quality of three vegetable fats (cocoa butter and two commercial fats) and three roasted nut oils (almond, hazelnut and peanut) used as raw material in the chocolate products manufacturing was studied. The hydroperoxide content, oxidative stability and fatty acid composition were determined and its health repercussion by atherogenicity and thrombogenicity indexes. Two commercial fats and cocoa butter showed higher oxidative stability, atherogenic and thrombogenic properties than oils because of its different fatty acid profiles. Peroxide value was a low reliability parameter of raw material shelf live. Rancimat presented a good correlation with the unsaturation index of different fats and oils, it was a better index than peroxide value. In the chocolate products manufacturing it would be advisable a good raw material selection and formulation in order to get a balance between technological properties, organoleptic qualities and the influence on the health. Those raw material with less primary oxidation and higher oxidative stability were also those of higher atherogenicity and thrombogenicity indexes.

[Level of double bonds in lipids in human plasma and erythrocytes]. / Uroven' dvoinykh sviazei v lipidakh plazmy i éritrotsitov cheloveka.

The unsaturation of plasma and red blood cell lipids and their total content of blood were determined in 212 donors. There was a significant individual variability of double binds in human blood lipids. A correlation was found between the magnitude of lipid unsaturation and the total blood lipid levels. The levels of double binds and total lipids did not depend upon the donors' sex and age. There were seasonal variations in the levels of double binds and lipid in plasma and red blood cells.

The nutritive value of dietary fats in relation to their chemical composition. Apparent fat availability and metabolizable energy in two-week-old chicks.

Broiler chicks at 2 wk of age were fed the following fats and oils at 4% in a corn-wheat-soybean basal diet: palm oil (PO); tallow (T1 and T2); tallow + soybean oil (50:50, TSO); tallow+acidulated soybean oil soapstock (50:50, TASO); soybean oil (SO); and linseed oil (LO). All of these, with the exception of T1, contained 5% soybean lecithin. The apparent fat availability (AFA) and AME of added fats ranged from 78.8 to 96.0% and from 7.32 to 8.95 kcal/g, respectively. Three fat sources (TSO, SO, and LO) resulted in the highest values for these two measurements, whereas PO, T1, T2, and TASO showed the lowest values. There was no difference for AME of diets among fat-supplemented treatments, regardless of the difference in the nutritive values of the fats and oils tested. The apparent availability of each fatty acid (AAFA) for C16:0, C18:0, C18:1, C18:2, and C18:3 was calculated from the analysis of the diets and excreta collected over a 4-d period. The results of the present study indicated that 2-wk-old chicks utilize TSO, SO, and LO more efficiently than PO, T1, T2, and TASO.

A histochemical method for the demonstration of unsaturated lipids.

A method has been developed for the histochemical demonstration of unsaturated lipids in light microscopy. It is a peracetic acid-thiocarbohydrazide-silver protein sequence followed by a physical development procedure. In the present study on paraffin and cryostat sections of liver, brain and ovary, unsaturated lipids were visualized as distinct reaction products coloured various shades of brown and black. The reaction products are easier to see and the method is more efficient than the peracetic acid-Schiff method.