Assessing the concentration of conjugated fatty acids within pomegranate seed oil using quantitative nuclear magnetic resonance (qNMR).

Introduction: Pomegranate seed is rich in oil, and seed oil of pomegranate consists of conjugated fatty acids with different percentages.

Objectives: The current contribution covers how to determine percentages of different isomeric conjugated fatty acids.

Methods: The percentages of these isomers are analysed by quantitative nuclear magnetic resonance (qNMR) using benzoic acid as an internal reference chemical with a well-defined amount.

Quantification of tributyltin in seawater using triple isotope dilution gas chromatography-inductively coupled plasma mass spectrometry achieving high accuracy and complying with European Water Framework Directive limits.

A triple isotope dilution GC-ICPMS method for the determination of tributyltin (TBT) was developed and validated to meet the European Water Framework Directive (WFD) requirements. The validation procedure involved the evaluation of trueness, precision (repeatability, intermediate precision), limit of detection (LOD) and limit of quantification (LOQ), stability, measurement uncertainty and traceability studies. The method is one of the most sensitive methods published to date with good accuracy, 103% average recovery in the range with %RSDs of 2.

The BIPM Mycotoxin Metrology Capacity Building and Knowledge Transfer Program: Accurate Characterization of a Pure Aflatoxin B Material to Avoid Calibration Errors.

The contamination of food and feed by mycotoxins, Aflatoxin B (AfB) being one of the most prominent examples, is of imminent concern to many countries. Regulatory limits for mycotoxins have been implemented, and these need to be supported by a sound measurement infrastructure for mycotoxin analysis in order to enforce and verify products, protect populations, and avoid technical barriers to trade in food stuffs. A Capability Building and Knowledge Transfer program on Metrology for Safe Food and Feed in Developing Economies was started at the International Bureau of Weights and Measures to allow National Metrology Institutes or Designated Institutes to work together to strengthen their national mycotoxin metrology infrastructure.

Analysis of olive oil for authentication and shelf life determination.

High-field proton (H) nuclear magnetic resonance (NMR) spectroscopy was applied for screening the fatty acyl contents of 33 olive oil samples from five different geographical regions of Turkey to do geographical discrimination analysis. The H NMR data were subjected to principal component analysis (PCA) and analysis of variance (ANOVA) to discriminate the origin of olive oils. The combination of discriminative screening by H NMR and ANOVA did not require further analysis of olive oil such as gas chromatography (GC).

The diverse behaviour of the P-Cl bonds in the spiro-cis-ansa spermidine derivative cyclotriphosphazene towards mono-functional nucleophilic reagents.

A number of new spiro-ansa spermidine derivative cyclotriphosphazenes (2-10) is synthesized in order to provide insight into the reaction mechanism for nucleophilic substitution. The structures of the compounds were determined by elemental analysis, mass (MS), (1)H, (19)F (for 9) and (31)P NMR spectroscopies. Compounds (2-8) and 9, 10 can be formed by a proton abstraction-chloride elimination and both the S(N)(1) and S(N)(2) reaction mechanisms, respectively.

Structural investigations of phosphorus-nitrogen compounds. 7. Relationships between physical properties, electron densities, reaction mechanisms and hydrogen-bonding motifs of N3P3Cl(6 - n)(NHBu(t))n derivatives.

A series of compounds of the N3P3Cl(6 - n)(NHBu(t))n family (where n = 0, 1, 2, 4 and 6) are presented, and their molecular parameters are related to trends in physical properties, which provides insight into a potential reaction mechanism for nucleophilic substitution. The crystal structures of N3P3Cl5(NHBu(t)) and N3P3Cl2(NHBu(t))4 have been determined at 120 K, and those of N3P3Cl6 and N3P3Cl4(NHBu(t))2 have been redetermined at 120 K. These are compared with the known structure of N3P3(NHBu(t))6 studied at 150 K.