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Human Milk Samples (human + milk_sample)
Selected AbstractsOxidation products of polyunsaturated fatty acids in infant formulas compared to human milk , A preliminary studyMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 12 2008Marie-Caroline Michalski Abstract Information about lipid oxidation in fresh and stored human milk compared with infant formulas is scarce. We aimed to assess n -6 and n -3 PUFA oxidation in these milks by measuring the 4-hydroxynonenal (4-HNE) and 4-hydroxyhexenal (4-HHE) content. Human milk samples (n = 4), obtained from volunteer mothers, were analyzed fresh and after 1 wk at 4°C or 24 h at 18°C. Vitamin E and malondialdehyde (MDA) were measured by HPLC and fatty acid profile by GC. The 4-HHE and 4-HNE contents were measured by GC-MS. Infant formulas (n = 10) were tested; their fat droplet size was measured by laser light scattering and observed by confocal laser scanning microscopy. Human milk samples contained 31.0 ± 6.3 g/L of lipids and 1.14 ± 0.26 mg/L of vitamin E. Fat droplets were smaller in infant formulas than reported in human milk. The (4-HHE/n -3 PUFA) ratio was 0.19 ± 0.01 ,g/g in fresh human milk (unchanged after storage) versus 3.6 ± 3.1 ,g/g in dissolved powder formulas and 4.3 ± 3.8 ,g/g in liquid formula. (4-HNE/n -6 PUFA) was 0.004 ± 0.000 ,g/g in fresh milk (0.03 ± 0.01 ,g/g after storage) versus 1.1 ± 1.0 ,g/g in dissolved powder formulas and 0.2 ± 0.3 ,g/g in liquid formula. Infant formulas also contained more MDA than human milk. n -3 PUFA were more prone to oxidation than n -6 PUFA. Whether threshold levels of 4-HHE and 4-HNE would be of health concern should be elucidated. [source] A selective and sensitive approach to characterize odour-active and volatile constituents in small-scale human milk samplesFLAVOUR AND FRAGRANCE JOURNAL, Issue 6 2007Andrea Buettner Abstract A sensitive and selective analytical approach was developed for the characterization of trace volatile and odorous substances in body fluids. The methodology was successfully applied for identification of more than 40 characteristic odorants in human milk. The technique comprises a modified stir bar sorptive extraction system in combination with two-dimensional gas chromatographic separation and parallel mass spectrometric and olfactometric characterization of the analytes. The present study shows that the technique can be used for both direct extractive sampling and headspace analysis, and that it is applicable for small sample volumes. Copyright © 2007 John Wiley & Sons, Ltd. [source] Oxidative status of human milk and its variations during cold storageBIOFACTORS, Issue 3 2004María Miranda Abstract Breastfeeding and human milk are widely accepted as optimal for human infants' nutrition. Nowadays lifestyle often makes it difficult to maintain or even initiate human lactation. This situation is mostly related to the workload of women away from home. New approaches are needed to enable maternal lactation under these circumstances. Human breastmilk storage for differed use is one possibility. The aim of this study was to assess changes in glutathione peroxidase (GPx) activity and in the concentration of the lipid peroxidation marker, malondialdehyde (MDA), when human milk was kept refrigerated or frozen. Thirty-two human milk samples were assayed for GPx activity and MDA concentration. Samples were divided in three aliquot portions, the first to be immediately analysed, the second to be refrigerated at 4°C and analysed 24 h thereafter, and the third to be frozen at -20°C and assayed after 10 days. GPx activity was significantly decreased in refrigerated and in frozen milk, when compared to their control samples. MDA was increased only in refrigerated milk but not in frozen samples. Thus, freezing seems better than refrigeration in order to prevent lipid peroxidation in stored human milk samples. [source] Concentrations of dioxins and other organochlorines (PCBs, DDTs, HCHs) in human milk from Seveso, Milan and a Lombardian rural area in Italy: a study performed 25 years after the heavy dioxin exposure in SevesoACTA PAEDIATRICA, Issue 4 2003J Weiss Aim: To investigate whether those who were exposed to high levels of the dioxin TCDD 25 years ago in Seveso, northern Italy still have higher than the expected levels of dioxins in their fat stores, and to investigate the concentrations of dioxins in the breast milk of mothers in Seveso and in two other regions in Italy. The load of vertically transmitted dioxins to the next generation, if being breastfed, was also investigated. Methods: As there may be a synergistic effect of mixtures of organic chlorines, the concentrations of pesticides such as DDTs and PCBs have also been studied in the same human milk samples. Breast milk from 12 mothers from Seveso, Central Milan and a Lombardian village was collected for analysis during the first week and 1 and 3 mo after delivery. Individual samples were used for the analysis of pesticides and PCBs, whereas dioxins were analysed in pooled samples from all 12 mothers on each occasion. Results: In human milk from Seveso, the TCDD concentration in fat calculated on a fresh weight basis was more than twice as high as the level in the other two regions, whereas the concentrations of investigated other toxins were lower in Seveso possible due to induction of the enzyme cytochrome P4501A, which means that the total level of dioxins was the same in all three locations. The congener profile, measured as mean toxic equivalency (TEQ) values, was the same in the Italian samples as previously reported from Stockholm. The calculations are based on the most recent WHO TCDD equivalency factors (TEF). The DDE concentration was higher in the samples from Milan than in the samples from the other two Italian regions, which may be due to the fact that, to a greater extent than in the other regions, Milanese food is imported from countries where DDT is still used as a pesticide. Conclusion: Twenty-five years after the dioxin catastrophe, human milk from mothers in Seveso has concentrations of the highly toxic dioxin congener TCDD that are more than twice as high as those in central Milan and a Lombardian village. This means that breastfed infants in Seveso still store an appreciable amount of TCDD in their body fat. The health consequences of this fact remain to be elucidated. The effect of the high load of DDTs in central Milan also has to be considered [source] | ||||||||||