Influence of food matrix delivery system on the bioavailability of vitamin D: A randomized crossover trial in postmenopausal women.

Objectives: Vitamin D insufficiency (blood 25-hydroxyvitamin D <50 nmol/L) is a global health problem. Vitamin D food fortification might be a solution, but knowledge is sparse on which food matrices yield the highest bioavailability. The aim of this study was to investigate the influence of different food matrices including complex formations with whey proteins on the human bioavailability of vitamin D.

Thermal degradation of metabolites in urine using multiple isotope-labelled internal standards for off-line GC metabolomics - effects of injector and oven temperatures.

Thermal processes are widely used in small molecule chemical analysis and metabolomics for derivatization, vaporization, chromatography, and ionization, especially in gas chromatography mass spectrometry (GC/MS). An optimized derivatization protocol has been successfully applied using multiple isotope labelled analytical internal standards of selected deuterated and C selected compounds, covering a range of different groups of metabolites for non-automated GC metabolomics (off-line). Moreover, the study was also realized in a pooled urine sample, following metabolic profiling.

Simultaneous Determination of L- and D-Amino Acids in Proteins: A Sensitive Method Using Hydrolysis in Deuterated Acid and Liquid Chromatography-Tandem Mass Spectrometry Analysis.

Determination of the L- and D-amino acid composition in proteins is important for monitoring process-induced racemization, and thereby protein quality loss, in food and feed. Such analysis has so far been challenging due to the need for sample hydrolysis, which generates racemization, thereby leading to an overestimation of D-amino acids. Here, validation of an LC-MS/MS-based method for the simultaneous determination of L- and D-amino acids in complex biological matrixes, like food and feed, was performed in combination with deuterated HCl hydrolysis.

Consumption of Whey in Combination with Dairy Medium-Chain Fatty Acids (MCFAs) may Reduce Lipid Storage due to Urinary Loss of Tricarboxylic Acid Cycle Intermediates and Increased Rates of MCFAs Oxidation.

Scope: The aim of the paper is to investigate whether changes in the metabolome could explain observed changes in body composition in overweight adults after consumption of butter with high level of medium-chain fatty acids (MCFAs) in combination with casein or whey.

Methods And Results: With GC-TOF and LC-Q/MS, metabolites in plasma and urine from a 12-week randomized double-blinded human intervention including 52-abdominally overweight adults were analyzed. The participants consumed 63 g per day of milk fat (high or low in MCFAs) and 60 g per day of protein (whey or casein).

Direct Derivatization vs Aqueous Extraction Methods of Fecal Free Fatty Acids for GC-MS Analysis.

A comprehensive and accurate determination of free fatty acids (FFA) is required for fecal metabolomic investigations. The present study compares three aqueous extraction methods (1) ULTRA-TURRAX(®), (2) whirl mixing and (3) basic ULTRA-TURRAX extraction of fecal FFA with a direct derivatization approach using ethyl chloroformate as the derivatization reagent before determination by gas chromatography-mass spectrometry. The direct derivatization method resulted in significantly higher estimations (P < 0.

Content and distribution of phytanic acid diastereomers in organic milk as affected by feed composition.

Phytanic acid (PA) is a bioactive compound found in milk that is derived from the phytol chain of chlorophyll, and the content of PA in milk fat depends on the availability of phytol from feed. In this study, the content of PA diastereomers was analyzed in milk sampled from five organic herds twice during the grazing season (May and September). The total content of PA was higher in September compared to May, but was not affected by breed (Danish Holstein or Danish Jersey).

Metabolomics reveals relationship between plasma inositols and birth weight: possible markers for fetal programming of type 2 diabetes.

Epidemiological studies in man and with experimental animal models have shown that intrauterine growth restriction (IUGR) resulting in low birth weight is associated with higher risk of programming welfare diseases in later life. In the pig, severe IUGR occurs naturally and contribute substantially to a large intralitter variation in birth weight and may therefore be a good model for man. In the present paper the natural form of IUGR in pigs was studied close to term by nuclear magnetic resonance (NMR-)based metabolomics.