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Köln, Germany

Lu F.S.H.,Technical University of Denmark | Nielsen N.S.,Technical University of Denmark | Baron C.P.,Technical University of Denmark | Diehl B.W.K.,Spectral Service AG | Jacobsen C.,Technical University of Denmark
Journal of Agricultural and Food Chemistry | Year: 2012

The objective of this study was to investigate the oxidative stability of dispersions prepared from different levels of purified marine phospholipid (PL) obtained by acetone precipitation, with particular focus on the interaction between α-tocopherol and PL in dispersions. This also included the investigation of nonenzymatic browning in purified marine PL dispersions. Dispersions were prepared by high-pressure homogenizer. The oxidative and hydrolytic stabilities of dispersions were investigated by determination of hydroperoxides, secondary volatile oxidation products, and free fatty acids, respectively, during 32 days of storage at 2 °C. Nonenzymatic browning was investigated through measurement of Strecker aldehydes, color changes, and pyrrole content. Dispersions containing α-tocopherol or higher levels of purified marine PL showed a lower increment of volatiles after 32 days storage. The results suggested that tocopherol is an efficient antioxidant in PL dispersions or that the presence of α-tocopherol and pyrroles may be the main reason for the high oxidative stability of purified marine PL dispersions. © 2012 American Chemical Society. Source

Mecozzi M.,European Commission - Joint Research Center Ispra | Pietroletti M.,European Commission - Joint Research Center Ispra | Monakhova Y.B.,Spectral Service AG | Monakhova Y.B.,Chernyshevsky Saratov State University
Marine Pollution Bulletin | Year: 2016

We inserted 190 FTIR spectra of plastic samples in a digital database and submitted it to Independent Component Analysis (ICA) to extract the "pure" plastic polymers present. These identified plastics were polypropylene (PP), high density polyethylene (HDPE), low density polyethylene (LDPE), high density polyethylene terephthalate (HDPET), low density polyethylene terephthalate (LDPET), polystyrene (PS), Nylon (NL), polyethylene oxide (OPE), and Teflon (TEF) and they were used to establish the similarity with unknown plastics using the correlation coefficient (r), and the crosscorrelation function (CC). For samples with r <. 0.8 we determined the Mahalanobis Distance (MD) as additional tool of identification. For instance, for the four plastic fragments found in the Carretta carretta, one plastic sample was assigned to OPE due to its r = 0.87; for all the other three plastic samples, due to the r values ranging between 0.83 and0.70, the support of MD suggested LDPET and OPE as co-polymer constituents. © 2016 Elsevier Ltd. Source

Bjorndal B.,University of Bergen | Strand E.,University of Bergen | Gjerde J.,University of Bergen | Bohov P.,University of Bergen | And 6 more authors.
Lipids in Health and Disease | Year: 2014

Background: Herring roe is an underutilized source of n-3 polyunsaturated fatty acids (PUFAs) for human consumption with high phospholipid (PL) content. Studies have shown that PL may improve bioavailability of n-3 PUFAs. Arctic Nutrition's herring roe product MOPL™30 is a PL: docosahexaenoic acid (DHA)-rich fish oil mixture, with a DHA:eicosapentaenoic acid (EPA) ratio of about 3:1, which is also rich in choline. In this pilot study, we determined if MOPL30 could favorably affect plasma lipid parameters and glucose tolerance in healthy young adults. Methods. Twenty female and one male adults, between 22 and 26 years of age, participated in the study. Participants took encapsulated MOPL30, 2.4 g/d EPA + DHA, for 14 days, and completed a three-day weighed food record before and during the capsule intake. Plasma lipids and their fatty acid (FA) composition, plasma and red blood cell (RBC) phosphatidylcholine (PC) FA composition, acylcarnitines, choline, betaine and insulin were measured before and after supplementation (n = 21), and one and four weeks after discontinuation of supplementation (n = 14). An oral glucose tolerance test was performed before and after supplementation. Results: Fasting plasma triacylglycerol and non-esterified fatty acids decreased and HDL-cholesterol increased after 14 days of MOPL30 intake (p < 0.05). The dietary records showed that PUFA intake prior to and during capsule intake was not different. Fasting plasma glucose was unchanged from before to after supplementation. However, during oral glucose tolerance testing, blood glucose at both 10 and 120 min was significantly lower after supplementation with MOPL30 compared to baseline measurements. Plasma free choline and betaine were increased, and the n-6/n-3 polyunsaturated (PUFA) ratio in plasma and RBC PC were decreased post-supplementation. Four weeks after discontinuation of MOPL30, most parameters had returned to baseline, but a delayed effect was observed on n-6 PUFAs. Conclusions: Herring roe rich in PL improved the plasma lipid profile and glycemic control in young adults with an overall healthy lifestyle. © 2014 Bjørndal et al.; licensee BioMed Central Ltd. Source

Monakhova Y.B.,Spectral Service AG | Monakhova Y.B.,Chernyshevsky Saratov State University | Diehl B.W.K.,Spectral Service AG
Analytical Methods | Year: 2016

A methodology utilizing 1H NMR spectroscopy has been developed to measure the concentration of hydrogen peroxide in hair sprays, nail treatments, hydrogen peroxide solutions for disinfection and chemical reagents. For sample preparation, only a dilution with DMSO-d6 to prevent coalescence of OH peaks and addition of an internal standard are required. The peroxide content is quantified by a distinct peak at δ 10.2 ppm against the signal of the methyl group of dimethylformamide (δ 2.9 ppm). The limit of detection of the developed methodology varied between 10-4% w/w for chemical reagent and disinfection products and 10-2% w/w for hair sprays and is sufficient to determine concentrations of hydrogen peroxide up to the maximum allowed limit. The coefficients of variation for intraday reproducibility do not exceed 0.9%. The 1H NMR spectra showed linearity for 10-100 μL sample volume (R2 = 0.9958). Recovery values varied in the range of 103-111% (106% on average). The stability of the analytical system was proved for seven days. The methodology was successfully applied to the analysis of nine authentic products. Furthermore, the analysis of signal positions and diffusion constants with varying peroxide concentrations (up to 30 w/w%) indicated the presence of H2O2-(H2O)6 and DMF-(H2O)3 intermolecular complexes in the analytical system. © 2016 The Royal Society of Chemistry. Source

Eiff J.,Spectral Service AG | Monakhova Y.B.,Spectral Service AG | Monakhova Y.B.,Chernyshevsky Saratov State University | Diehl B.W.K.,Spectral Service AG
Journal of Agricultural and Food Chemistry | Year: 2015

A nuclear magnetic resonance (NMR) spectroscopic method was tested to control 12 vitamins and accompanying substances in multivitamin preparations. The limits of detection (LODs) and limits of quantification (LOQs) varied in the 9.0-77.0 mg/kg and in the 34.5-93.5 mg/kg range, respectively. The coefficients of variation (CVs) ranged between 0.9% and 12%. The 1H NMR spectra showed linearity for the 140-260 mg sample weight (R2 > 0.918). The NMR spectra of multivitamin preparations showed the presence of different degradation products of ascorbic acid. The NMR method was applied to 13 different multivitamin preparations including tablets, capsules, and effervescent tablets with average recovery rates between 85% and 132%. A number of accompanying substances (citric acid, mannitol, saccharin, cyclamate, sum of steviol glycosides, and butylhydroxytoluene) were additionally identified and quantified. NMR was found to be suitable for the simultaneous qualitative measurement of water- and fat-soluble vitamins and accompanying substances and shows some promise for quantitative determination of at least 5 vitamins (B1, B3, B5, B6, and E) in multivitamin preparations. © 2015 American Chemical Society. Source

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