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In recent years it has been confirmed that the consumption of olive oil prevents the oxidation of biomolecules owing to its monounsaturated fatty acids (MUFA) and phenolic content. The main objective of the study was to develop an ultra-high-performance liquid chromatography (UHPLC) tandem mass spectrometry (MS/MS) method for the determination of phenolic compounds in human high-density lipoprotein (HDL) samples. At the same time, the influence of olive oil consumption on the phenolic metabolite levels was evaluated in a European population. The participants were 51 healthy men, aged 20-60. They were randomized to two consecutive intervention periods with the administration of raw olive oil with low and high polyphenolic content. The UHPLC-MS/MS analytical method has been validated for hydroxytyrosol and homovanillic acid in terms of linearity ( r2 = 0.99 and 1.00), repeatability (5.7 and 6.5%) reproducibility (6.2 and 7%), recovery (98 to 97%), limits of detection (1.7 to 1.8 ppb) and quantification (5.8 and 6.3 ppb).The levels of the studied metabolites increased significantly after high polyphenolic content virgin olive oil ingestion ( p <0.05) compared with lowpolyphenolic content olive oil. Virgin olive oil consumption increases the levels of phenolic metabolites in HDL and thus provides human HDL with more efficient antioxidant protection. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objective: To investigate differences in fatty acid and sn-2 fatty acid composition in colostrum, transitional and mature human milk, and in term infant formulas.Setting: Departament de Nutrició i Bromatologia, University of Barcelona, Spain and University Hospital of Granada, Spain.Subjects: One-hundred and twenty mothers and 11 available types of infant formulas for term infants.Design: We analysed the fatty acid composition of colostrum (n=40), transitional milk (n=40), mature milk (n=40) and 11 infant formulas. We also analysed the fatty acid composition at sn-2 position in colostrum (n=12), transitional milk (n=12), mature milk (n=12), and the 11 infant formulas.Results: Human milk in Spain had low saturated fatty acids, high monounsaturated fatty acids and high linolenic acid. Infant formulas and mature human milk had similar fatty acid composition. In mature milk, palmitic acid was preferentially esterified at the sn-2 position (86.25%), and oleic and linoleic acids were predominantly esterified at the sn-1,3 positions (12.22 and 22.27%, respectively, in the sn-2 position). In infant formulas, palmitic acid was preferentially esterified at the sn-1,3 positions and oleic and linoleic acids had higher percentages at the sn-2 position than they do in human milk.Conclusion: Fatty acid composition of human milk in Spain seems to reflect the Mediterranean dietary habits of mothers. Infant formulas resemble the fatty acid profile of human milk, but the distribution of fatty acids at the sn-2 position is markedly different. [ABSTRACT FROM AUTHOR]

Objective: To assess the effect of long-chain polyunsaturated fatty acids (LCPUFA)- and vitamin E-supplemented formula feeding on erythrocyte and plasma alpha-tocopherol (VE), and plasma retinol (VA) concentrations in neonates and to compare these values with those found in infants feeding on infant formula without LCPUFA or breast milkSetting: University Hospital of Granada, Spain.Subjects: 49 full-term infants.Design and Intervention: Subjects who chose not to breast feed were fed either (i) unsupplemented infant formula (F) or (ii) infant formula supplemented with LCPUFA and vitamin E (FL). Alpha-tocopherol and retinol were measured at 7 days, 1 month and 3 months.Results: Plasma and erythrocyte VE concentrations and plasma VE/total lipids ratio increased significantly in all groups at 1 month of life (P < 0.05), but did not change significantly between 1 month and 3 months in any group (P > 0.05). Erythrocyte VE and VA retinol concentrations were higher in infants fed an infant formula than in breast milk-fed infants at 1 month of life (P < 0.05). Finally, there were no significant differences in plasma or erythrocyte VE levels, plasma VA or plasma VE/total lipid ratio between any groups at 3 months of life (P > 0.05).Conclusion: Infants fed on LCPUFA- and vitamin E-supplemented infant formula for 3 months have similar vitamin E and A status to infants fed on breast milk or infant formula without LCPUFA supplementation. [ABSTRACT FROM AUTHOR]

Objectives: To assess the incorporation of n-3 polyunsaturated fatty acids (PUFA) in plasma and erythrocyte lipids of elderly subjects after ingestion of very low doses of fish oil. The effects on alpha-tocopherol and retinol concentrations were also studied.Setting: Municipal nursing home in Barcelona, Spain.Subjects: Forty-five elderly subjects aged 60-92 y.Design and Intervention: Subjects received a non-commercialized milk formula containing 1% fish oil for 15 months, which provided 0.40 g/d of n-3 PUFA. Fatty acid profiles and antioxidant concentrations were measured before and after the intervention period.Results: Fish oil ingestion was associated with significant increases in total n-3 PUFA in plasma and erythrocytes by 32% and 18%, respectively. Eicosapentaenoic (EPA) and docosahexaenoic (DHA) acid concentrations were higher after the ingestion period both in plasma and erythrocytes (P < 0.05), whereas linoleic and arachidonic acids remained unchanged. The n-6/n-3 ratio decreased by 21% in plasma and by 16% in erythrocytes (P < 0.05). Moreover, younger subjects showed a greater incorporation of EPA and DHA than older subjects. Plasma alpha-tocopherol and retinol concentrations did not vary significantly, whereas erythrocyte alpha-tocopherol was significantly higher after the intervention period.Conclusion: This study shows that low doses of n-3 PUFA supplemented with adequate amounts of alpha-tocopherol can be incorporated into blood lipids in elderly subjects without lowering their antioxidant concentrations. [ABSTRACT FROM AUTHOR]

mentation because of its nutritional and immunological properties. Banked human milk is stored at low temperature, which may produce losses of some bioactive milk components. During lactation, colostrum provides the requirements of the newborn during the first days of life. The aim of this study was to evaluate the effect of cooling storage at 4°C and freezing storage at -20°C and -80°C on bioactive factors in human colostrum. For this purpose, the content of IgA, growth factors such as epidermal growth factor, transforming growth factor (TGF)-β1 and TGF-β2, and some cytokines such as IL-6, IL-8, IL-10, and tumor necrosis factor (TNF)-a, and its type I receptor TNF-RI, were quantified. Some colostrum samples were stored for 6, 12, 24, and 48 h at 4°C and others were frozen at -20°C or -80°C for 6 and 12 mo. We quantified IgA, epidermal growth factor, TGF-β1, and TGF-β2 by indirect ELISA. Concentrations of IL-6, IL-10, and TNF-a cytokines, IL-8 chemokine, and TNF-RI were measured using the BD Cytometric Bead Array (BD Biosciences, Erembodegem, Belgium). Bioactive immunological factors measured in this study were retained in colostrum after cooling storage at 4°C for at least 48 h, with the exception of IL-10. None of the initial bioactive factor concentrations was modified after 6 mo of freezing storage at either -20°C or -80°C. However, freezing storage of colostrum at -20°C and -80°C for 12 mo produced a decrease in the concentrations of IgA, IL-8, and TGF-β1. In summary, colostrum can be stored at 4°C for up to 48 h or at -20°C or -80°C for at least 6 mo without losing its immunological properties. Future studies are necessary to develop quality assurance guidelines for the storage of colostrum in human milk banks, and to focus not only on the microbiological safety but also on the maintenance of the immunological properties of colostrum. [ABSTRACT FROM AUTHOR]

Human milk is considered the optimal nutritional source for infants. Banked human milk is processed using low-temperature, long-time pasteurization, which assures microbial safety but involves heat denaturation of some desirable milk components such as IgA. High-pressure processing technology, the subject of the current research, has shown minimal destruction of food macromolecules. The objective of this study was to investigate the influence of pressure treatments on IgA content. Moreover, bacterial load was evaluated after pressure treatments. The effects of high-pressure processing on milk IgA content were compared with those of low-temperature, long-time pasteurization. Mature human milk samples were heat treated at 62.5°C for 30 min or pressure processed at 400, 500, or 600 MPa for 5 min at 12°C. An indirect ELISA was used to measure IgA in human milk whey obtained after centrifugation at 800 × g for 10 min at 4°C. All 3 high-pressure treatments were as effective as low-temperature, long-time pasteurization in reducing the bacterial population of the human milk samples studied. After human milk pressure processing at 400 MPa, 100% of IgA content was preserved in milk whey, whereas only 72% was retained in pasteurized milk whey. The higher pressure conditions of 500 and 600 MPa produced IgA retention of 87.9 and 69.3%, respectively. These results indicate that high-pressure processing at 400 MPa for 5 min at 12°C maintains the immunological protective capacity associated with IgA antibodies. This preliminary study suggests that high-pressure processing may be a promising alternative to pasteurization in human milk banking. [ABSTRACT FROM AUTHOR]

Introduction: Childhood obesity has become a worldwide epidemic. Spain is the third European country in childhood obesity (IDEFICS study, 2011 ) with 44.5% of overweight children (ALADINO study, 2010-2011). In obesity, fatty acids (FAs) composition of blood and tissues changes, affecting a wide number of important physiological functions relating to body fatness. As is known, saturated FAs are related to obesity and lower intake of these FAs is associated with decreased body weight and inflammation markers. Objective: To identify the relationship between plasma fatty acid composition, anthropometric indicators of adiposity and blood pressure in overweight and obese adolescents. Methodology: This study comprised 126 overweight and obese adolescent participants in the EVASYON study, aged 12-17 years, from Granada, Zaragoza, Madrid and Pamplona. They received a treatment based on calorie-restricted diet, increased physical activity, psychological therapy and nutritional education. FA composition was determined in plasma samples before starting treatment and at 2, 6 and 12 months of intervention by fast gas chromatography. Results: Studied anthropometric indicators [weight, body mass index (BMI), fat-muscle index (FMI), body fat, waist circumference (WC), waist-hip ratio, waist-height ratio] and blood pressure decreased with the treatment. Myristic, stearic and linoleic acids decreased and oleic acid, EPA and DHA increased after 2 months of intervention. Myristic acid was positively correlated with BMI, FMI, body fat, WC, waist-height ratio and systolic blood pressure, and stearic acid with BMI. Conclusions: Myristic and stearic acids were associated with anthropometric indicators of adiposity. [ABSTRACT FROM AUTHOR]

For the first time, a procedure for the simultaneous determination of the iodinated drug amiodarone and its major metabolite, N-desethylamiodarone, in sludge from urban sewage treatment plants (STPs) is proposed. Matrix solid-phase dispersion (MSPD) followed by on-line cationic exchange clean-up, in modular configuration, was used as sample preparation technique. Liquid chromatography with tandem mass spectrometry (LC-MS/MS), based on a hybrid quadrupole time-of-flight (QTOF) system, was employed for the selective determination of target compounds. The optimized procedure provided exhaustive recoveries with little effect of the sample matrix in the efficiency of electrospray ionization (ESI). The overall recoveries of the method ranged between 95 and 111%, for samples spiked at different concentration levels. The achieved limits of quantification (LOQs) remained below 10ngg(-1) for both compounds, and the linear response range extended up to 2500ngg(-1). Amiodarone and N-desethylamiodarone were ubiquitous in sludge samples, from different STPs located in the Northwest of Spain, with maximum concentrations above 300ngg(-1) referred to the freeze-dried matrix. They were also present in stabilized sludge (mixed with lime and thermally dehydrated), which is mostly disposed in agriculture fields as fertilizer. Furthermore, mono-iodinated analogues of amiodarone and N-desethylamiodarone were also tentatively identified in some samples from their accurate MS and MS/MS spectra., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Background: Maternal genetics and feeding before and during pregnancy, different maternal metabolic pathologies, as well as nutrient intakes of newborns in their first months of life may be involved in the obesity aetiology and its long-term consequences. The possible role of these and others factors, the mechanisms and the effects on the metabolism, and the development of this disease need further research., Objective: To acquire more knowledge about foetal adipose tissue development and the influence of genetic, dietetic and environmental factors on the risk to suffer from obesity., Methodology: Four study groups have been established with 30 pregnant women in each one: 1) control group; 2) mothers with glucose intolerance/gestational diabetes; 3) women with low weight gain during pregnancy, and 4) women with overweight/obesity at the beginning of the pregnancy. The magnitudes to be studied are: 1) dietary intake; 2) life-style habits; 3) physical activity; 4) anthropometry and body composition; 5) haematological study; 6) biochemical study (lipid and metabolic biomarkers); 7) immune function profile related to nutritional status; 8) psychological profile; 9) genetic biomarkers, and 10) microbiological markers; all of them in relation to the development of the foetal adipose tissue in the first stages of life and the risk of suffering from obesity in the future., Conclusion: This project, coordinated by the Department of Paediatrics of the School of Medicine in the University of Granada, and with the collaboration of well-known and expert research groups, tries to contribute to the knowledge about the obesity aetiology in infancy and its subsequent development in later periods of life.

A new method for the determination of the main isomers of conjugated linoleic acid (CLA) in human and animal plasma was developed by gas chromatography coupled to flame ionization detection (GC-FID). The new method introduces three main advantages in comparison to the current available methodologies: firstly it does not require previous lipid extraction, secondly the chromatographic separation of CLA isomers was performed on an Rtx-2330 column significantly shorter and thinner than the typical long highly polar capillary columns in use that allows a faster analysis than in current methodologies, and thirdly the amount of sample needed to perform the analyses was substantially lower than the amount used in current routine methodologies. Its application to human plasma and rat plasma showed to be robust and reliable for quick and correct identification of the main CLA isomers in particular, and the total fatty acid profile in general, in routine analysis.

A new method for the determination of phospholipid fatty acids in biological samples, combination of solid-phase extraction (SPE) and fast gas chromatography (GC) was developed. Its application to human plasma and human erythrocytes showed to be robust and reliable for quick and correct identification in routine analysis.

A rapid direct method (Method I) for measuring gamma- and alpha-tocopherols in human milk was developed and validated using reversed-phase high-performance liquid chromatography with ultraviolet/visible (UV-vis) detection. Human milk, with an internal standard (alpha-tocopherol acetate) added, was diluted in hexane. The chromatographic system consisted of a short column (50 mm x 2.1mm I.D., 3 microm particle size) that allowed the separation of the gamma- and alpha-tocopherols in less than 6 min. The new direct method (Method I) was compared with other methods. Method II (saponification with ultraviolet/visible detection) determined 24% and 22% less gamma- and alpha-tocopherols, respectively. Method III (saponification with evaporative light scattering detection) gave the same values for alpha-tocopherol content as Method II. However, the amount of sample used in the application of Method III was higher than that used in Method II. Furthermore, Method I uses smaller amounts of solvents, and it is simpler and faster than Methods II or III. Only a small volume of sample is needed, which is an additional advantage for biological assays.

Here we studied whether the chemical structure of dietary arachidonic and docosahexaenoic acids in full-term infant diets affects their incorporation into erythrocyte membrane phospholipids. From birth to 3 months, infants were fed breast milk (n = 9) or formula milk containing arachidonic acid and docosahexaenoic acid provided by egg phospholipids (n = 10) or by low-eicosapentaenoic acid fish oil and fungal triglycerides (n = 10). We compared the fatty acid composition of erythrocyte phosphatidylethanolamine, phosphatidylcholine and sphingomyelin before and after administration of the experimental diet. At 3 months, infants on formula milk showed lower concentrations of docosahexaenoic acid (in phosphatidylcholine and in phosphatidylethanolamine) and arachidonic acid (in phosphatidylcholine) than those receiving breast milk. We conclude the incorporation of the two fatty acids into erythrocyte phospholipids depends mainly on the lipid composition of the diet received rather than the chemical form in which they are delivered.

Vitamin C is an antioxidant that can be considered a possible biomarker of oxidative stability in human milk. A high-performance liquid chromatographic method was developed and validated for determining the total Vitamin C (ascorbic acid and dehydroascorbic acid) and ascorbic acid levels in human milk. This method was then compared with an enzymatic method (a Colorimetric technique) for quantifying ascorbic acid levels. Repeatability and reproducibility were acceptable for all methods. However, the high-performance liquid chromatography (HPLC) technique provided more satisfactory results than the enzymatic method due to this last method detected 37% less ascorbic acid and does not determine the total Vitamin C because of the enzymatic method cannot reduce the dehydroascorbic acid (DHA) to ascorbic acid. Furthermore, the HPLC method has the added advantages that it requires less reagents and material, and is simpler and less time consuming than the enzymatic method. In conclusion, the drawbacks of this enzymatic method would justify its substitution for a HPLC method.

The Mediterranean diet, in which olive oil is the main source of fat, has been associated with a reduced incidence of coronary heart disease (CHD) and low blood pressure levels. Virgin olive oil (VOO), besides containing monounsaturated fat, is rich in phenolic compounds (PC) with antioxidant properties. The aim of this study was to examine the antioxidant and anti-hypertensive effect of two similar olive oils, but with differences in their PC (refined: 14.7 mg/kg versus virgin: 161.0 mg/kg), in 40 males with stable CHD. The study was a placebo controlled, crossover, randomized trial. A raw daily dose of 50 mL of VOO and refined olive oil (ROO) were sequentially administered over two periods of 3 weeks, preceded by 2-week washout periods in which ROO was used. Lower plasma oxidized LDL (p < 0.001) and lipid peroxide levels (p = 0.003), together with higher activities of glutathione peroxidase (p = 0.033), were observed after VOO intervention. Systolic blood pressure decreased after intake of VOO (p = 0.001) in hypertensive patients. No changes were observed in diastolic blood pressure, glucose, lipids, and antibodies against oxidized LDL. Consumption of VOO, rich in PC, could provide beneficial effects in CHD patients as an additional and complementary intervention to the pharmacological treatment.

Powder infant milk formula quality deterioration and consequently the termination of shelf life results in the appearance of off-flavors mainly determined by a composite effect of spoilage volatiles. A headspace gas chromatographic method to determine propanal, pentanal and hexanal as the main volatiles present in the headspace of powder infant formula oxidation is described as a rapid indication of oxidative status. Under optimum conditions the limits of detection for propanal, pentanal and hexanal were 17.19, 16.87 and 19.60 ng and the limits of quantification were 37.37, 31.96 and 35.97, respectively. The calibration graphs of the method were linear from 25 to 1500, 20 to 3500 and 30 to 8500 ng for propanal, pentanal and hexanal, respectively, with determination coefficients exceeding 0.99. The precision results showed that the relative standard deviations of the repeatability and reproducibility were between 2.2 and 5.5%. The analytical method was simple, rapid, and reliable and permitted the analysis of a large number of formulas using small sample volumes.

A rapid, sensitive method has been developed for the simultaneous determination of retinol acetate, delta-, gamma-, alpha-tocopherol and alpha-tocopherol acetate. We compare two experimental procedures for simultaneous direct solvent extraction of these vitamins without previous saponification. Method I: the fat milk sample was extracted with ethanol-hexane and injected directly into the chromatographic column. Method II: the power milk sample was extracted with ethanol-hexane and also injected directly into the column. Under optimum conditions the limits of detection for retinol acetate, delta-, gamma-, alpha-tocopherol and alpha-tocopherol acetate were 0.33, 21.2, 32.9, 32.5 and 3.2 ng and the limits of quantification were 0.42, 25.3, 37.9, 36.8 and 6.3 ng, respectively. The precision results showed that the relative standard deviations of repeatability and reproducibility were between 0.74 and 5.7%.

We developed and validated a new high-performance liquid chromatographic method for the separation of phospholipid classes in human milk, infant formulas and phospholipidic sources of long-chain polyunsaturated fatty acids (LC-PUFAs) used in paediatric nutrition. Phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylserine and sphingomyelin were separated in less than 25 min using an Extrasil silica column (150 x 4.0 mm I.D., 3-microm particle size) by isocratic elution with a mixture of isopropanol-hexane-water. Phospholipids were determined by an evaporative light-scattering detector. Several chromatographic conditions were assayed to optimise the method, whose suitability is shown by the detection limits, linearity ranges and precision rates obtained. The main advantages of the proposed method are its speed and the direct determination of the main phospholipids present in human milk, infant formulas and the phospholipid sources of LC-PUFAs used in paediatric nutrition.

Objective: To measure the incorporation of oleic acid and antioxidants (phenols and vitamin E) to low density lipoprotein (LDL) after acute and short-term ingestion of virgin olive oil. To study whether this incorporation contributes to an increase in LDL resistance to oxidation., Setting: Department of Food and Nutrition, University of Barcelona, Spain and Department of Lipids and Cardiovascular Epidemiology, IMIM, Barcelona, Spain., Subjects: Sixteen healthy volunteers aged 25-65 y., Design and Interventions: To observe the change in the fatty acid profile, vitamin E, phenolic compounds and LDL oxidation-related variables after the postprandial phase and after daily ingestion of olive oil for one week., Results: Few changes were observed in the postprandial phase. However, after a week of olive oil consumption there was an increase in oleic acid (P=0.015), vitamin E (P=0.047), phenolics (P=0.021) and lag time (P=0.000), and a decrease in the maximum amount of dienes (P=0.045) and oxidation rate (P=0.05)., Conclusion: After ingestion of virgin olive oil, an increase in antioxidants and oleic acid in LDL was observed as well as an improvement of LDL resistance to oxidation. Our results support the idea that daily ingestion of virgin olive oil could protect LDL from oxidation., Sponsorship: This study was supported by a research grant from Spain (ALI 97-1607-C02-02).

The distribution of long-chain saturated fatty acids in triglycerides is different in infant formulas to that in human milk. In human milk, palmitic acid is predominantly esterified in the sn-2 position (beta-position) of the triglycerides, whereas in infant formulas, it is esterified mainly in the sn-1,3 positions (alpha,alpha'-positions). The specific distribution of the fatty acids in the triglyceride plays a key role in lipid digestion and absorption. We studied fatty-acid, calcium and magnesium composition in the faeces of three groups of at term newborn infants fed different diets: Group A (n=12) was fed from birth to 2 months with human milk (66% palmitic acid in beta-position), Group B (n=12) was fed with formula alpha (19% palmitic acid esterified in beta-position) for 2 months, and Group C (n=12) was fed with formula alpha during the first month and with formula beta (44.5% palmitic acid in beta-position) during the second month. Samples were taken at the end of the first month (t0) and at the end of the second month (t1). Groups A and C presented significantly lower contents of palmitic acid in faeces at t1 than at t0, whereas in Group B, amounts remained similar. Faecal calcium in Groups A and C decreased in the second month (t1), although the fall was no statistically significant. In Group B, calcium amounts showed no change. We found that infant formula beta when compared with infant formula alpha reduced significantly the contents of total fatty acids and palmitic acid in faeces. We conclude that palmitic acid in beta-position is, therefore, beneficial for term infants.

Alongside the French paradox, the REGICOR Study (Girona, Spain) has shown another paradox in the Mediterranean area: a high prevalence of cardiovascular risk factors with low incidence of myocardial infarction in the population of Girona, Spain. The antioxidant effects associated with olive oil consumption could explain part of this 'Mediterranean Paradox'. Virgin olive oils processed by two centrifugation phases and with low fruit ripeness have the highest levels of antioxidant content. The total content of phenolic compounds (PC) from virgin olive oil could delay LDL oxidation. The content and nature of olive oil PC have a high influence in the antioxidant capacity of an olive oil. PC from diet could bind human LDL in non-supplemented volunteers. PC from virgin olive oil could bind LDL and tyrosol is bioavailable in humans from ingestion of virgin olive oil in its natural form.

An alternative method to determine the sn-2 monopalmitin in infant formulas was developed and validated. This method offers many advantages over the traditional methods. It follows the official method in the first steps, purification of the fat or oil through an alumina column, and subsequently the triglycerides are incubated with pancreatic lipase in order to obtain the sn-2 monoglycerides. In traditional methods the sn-2 monoglycerides are separated by preparative thin-layer chromatography and then, the 2-monoglycerides are converted into the corresponding fatty acid methyl esters and analysed by gas chromatography. In our method, separation, quantification and identification of the sn-2 monoglycerides were achieved by high-performance liquid chromatography with evaporative light-scattering detection. The detection limit (0.19 microg), quantification limit (0.38 microg), linearity range (r=0.999, range 1-200 microg) and precision (SD=1.10) show the suitability of the proposed method. This method is faster, cheaper and simple and does not consume large quantities of reagents and materials.

A reversed-phase HPLC method with diode-array detection was used to simultaneously determine retinol, alpha-tocopherol and beta-carotene in human plasma and low-density lipoproteins. An aliquot of sample was de-proteinized with ethanol containing beta-tocopherol acetate as internal standard, and the analytes were extracted twice with hexane. The solvent was evaporated to dryness under a stream of nitrogen and the residue was redissolved in methanol to be injected directly into the HPLC system. A multiple solvent system based on methanol, butanol and water at a flow-rate of 2 ml/min and held at 45 degrees C provided clear separation of these compounds in only 8 min. The method showed good linearity, precision and accuracy for all compounds. Owing to its simplicity, this method may be useful in routine clinical and epidemiological work.

Objective: Milk triglycerides from colostrum, transitional and mature human milk, were analyzed and compared in order to determine the differences in triacylglycerol composition throughout lactation., Setting: Department of Food and Nutrition, University of Barcelona, Spain, and Neonatology Department of the University Hospital of Granada, Spain., Subjects: Twenty-two healthy lactating women aged 21-35., Design and Interventions: The triacylglycerol profiles of 47 breast milk samples including colostrum (1-3 days), transitional milk (7-10 days) and mature milk (25-60 days) were analyzed by high-performance liquid chromatography (HPLC), with light-scattering detection (LSD)., Results: Significant differences regarding several triglycerides were found between three milk classes when the Kruskal-Wallis nonparametric test was applied to 47 human milk samples that had been compared using the complete chromatographic triacylglycerol profile. The ANOVAS for each equivalent carbon number (ECN) group of triglycerides revealed significant differences between colostrum, transitional milk and mature milk. By the discriminant analysis of triacylglycerol percentages, in 19 colostrum samples, 14 transitional milk samples and 14 mature milk samples, three milk types were distinguished, and three triglycerides (peak no. 4, LnOO and SOO) were found to be the most predictive variables over all the triacylglycerol profile or ECN groups., Conclusions: Each state of lactation shows a specific profile of triacylglycerol composition in human milk. However the two most abundant triacylglycerides in colostrum, POO and POL, which account for more than 49% of the total, are also dominant in transitional (34%) and mature milk (42%).

A quick and direct method for measuring tocopherols (alpha, beta+gamma and delta) in vegetable oils has been developed using RP-HPLC with UV detection. Previous extraction of tocopherols is not required. The oil is diluted in hexane and an aliquot is mixed with ethanol containing an internal standard (alpha-tocopherol acetate). The chromatographic system consists of an ODS-2 column with a methanol-water mobile phase. Tocopherols are detected at 292 nm in less than 5 min after injection. The method is precise (RSD=2.69%) and has a high mean recovery (98.14%).

Inulin is a naturally occurring carbohydrate with beneficial nutritional and technological properties. A high-performance liquid chromatographic (HPLC) method was developed for the quantitative determination of these beta-fructans in meat products, containing this type of additive. The method includes extraction of inulin with hot water, followed by hydrolysis with inulinase enzyme, and determination of the released fructose by HPLC with refractive index detection. An internal standard of rhamnose was used to quantify fructose. The method incorporates a sample blank (without inulinase hydrolysis) for each specimen to subtract contributions of free fructose and fructose from sucrose. The results showed good precision with average RSDs of 2.4% for repeatability and 5.2% for reproducibility. Analytical recovery ranged from 102 to 106%. Satisfactory linearity (r=0.999) was obtained.

A reversed-phase high-performance liquid chromatographic method was developed for the determination, in one run, of alpha-tocopherol and beta-carotene in virgin olive oil. The method involved a rapid saponification and a later extraction with a mixture of hexane-ethyl acetate. The chromatographic system consists of an ODS-2 column with a mobile phase of methanol-water-butanol and a diode-array detector. Linearity, precision, recovery and sensitivity were satisfactory. The main advantage of the proposed method is the speed and simultaneous determination of both compounds at the same time.

Human milk contains small but nutritionally significant amounts of long-chain polyunsaturated fatty acids (LCP), such as arachidonic (AA, 20:4n-6) and docosahexaenoic (DHA, 22:6n-3) acids, which are not present in most infant formulae. In the present study, the fatty acid composition of plasma and erythrocytes was determined at birth and again at 7 days, 1 and 3 months in 49 healthy full-term infants (37-42 week's gestation). One group of infants was fed exclusively with human milk (n=16) and the others were randomly assigned to a standard term formula (F) (n=15) or the same formula with egg yolk lecithin providing DHA (0.15%) and AA (0.30%) (LCP-F) (n=18). Plasma and erythrocyte LCP values of the three dietary groups did not differ at 7 days of age, but the contents of DHA and AA in plasma and erythrocytes at 1 and 3 months were significantly lower (P<0.05) in infants fed non supplemented formula than in infants fed breast milk and supplemented formula. There were no differences in plasma or erythrocyte AA or DHA concentrations between the group fed breast milk and the group fed supplemented formula during the period studied.

We measured plasma and erythrocyte vitamin E (VE) and plasma vitamin A (VA) profiles in 48 full-term and 8 preterm pairs of neonates and their mothers at birth and we determined whether there is any relationship between maternal and umbilical cord for the nutrients measured. At the same time, we assessed the influence of the delivery type and neonate anthropometric measurements on maternal and cord blood VA and VE levels. We measured vitamin levels in vein and arterial blood in order to establish differences due to fetal metabolism. To determine the influence of pregnancy on vitamin levels, we compared the maternal results with data from a group of 13 non-pregnant women. Cord blood had lower plasma VE (arterial 275.8+/-71.7 microg/dl and vein 282.89+/-64.4 microg/dl values), erythrocyte VE (arterial 256.96+/-50.41 microg/dl packet cells and vein 257.41+/-44.35 microg/dl values), and VA levels (arterial 26.72+/-11.83 microg/dl and 27.15+/-10.05 microg/dl values) and a lower vitamin E/total lipids ratio (VE/LT) (arterial 1.60+/-0.4 and vein 1.62+/-0.3 values) than maternal blood (1474.62+/-424.51 microg/dl, 305.94+/-54.75 microg/dl packet cells, 41.03+/-18.83 microg/dl, 2.34+/-0.5, respectively). VA levels were higher in preterm than full-term neonates (P<0.05). Plasma and erythrocyte VE levels were not correlated in maternal blood but were correlated in neonates and infants (r>0.40; P<0.01). We found a good correlation between erythrocyte tocopherol of maternal and cord blood (r>0.40; P<0.01), although there was no correlation with plasma VE values. Cord vein plasma VE levels were higher than cord arterial blood measurements (P<0.01). The plasma VE and VE/LT of the mother and cord following vaginal delivery were higher than measurements from caesarean delivery (P<0.05), although erythrocyte levels were similar. The plasma VE level was higher in mothers at delivery than non-pregnant women.