The objective of this study is the qualitative and quantitative analysis of encapsulated fish oil supplements by utilizing high-resolution multinuclear ( 1 H, 13 C, 31 P) and multidimensional NMR spectroscopy. By employing sophisticated 2D NMR experiments, such as HSQC-TOCSY, band-selective HSQC and semi-selective constant-time HMBC we performed a systematic two-dimensional analysis of the various components in fish oil. The present analysis offered a solid proof and confirms earlier assignments based on model compounds. Moreover, this study revealed the presence of n-1 acyl chains and trans fatty acids in concentrations ranging from 1.9-2.9% and 3.7-5.2%. Application of 31 P NMR spectroscopy to the analysis of micro-constituents in fish oil supplements allowed the fast and accurate determination of additional minor compounds in it. Quantitative determination of the various compounds in the supplements was achieved upon integration of the appropriate NMR signals in the relevant spectra.

Fourier transform can be effectively used for processing of sparsely sampled multidimensional data sets. It provides the possibility to acquire NMR spectra of ultra-high dimensionality and/or resolution which allow easy resonance assignment and precise determination of spectral parameters, e.g., coupling constants. In this chapter, the development and applications of non-uniform Fourier transform is presented.

A methodology based on 13C NMR spectroscopy was employed to detect and quantify fourteen mono-, di- and trisaccharide molecules in authentic Greek honey samples with no prior separation.

The compressed sensing NMR (CS-NMR) is an approach to processing of nonuniformly sampled NMR data. Its idea is to introduce minimal l(p) -norm (0 < p ≤ 1) constraint to a penalty function used in a reconstruction algorithm. Here, we demonstrate that 2D CS-NMR spectra allow the full spectral assignment of near-symmetric β-cyclodextrin derivatives (mono-modified at the C6 position). The application of CS-NMR ensures experimental time saving and the resolution improvement, necessary because of very low chemical shift dispersion. In the overnight experimental time, the set of properly resolved 2D NMR spectra required for the unambiguous assignment of mono(6-deoxy-6-(1-1,2,3-triazo-4-yl)-1-propane-3-O-(phenyl)) β-cyclodextrin was obtained. The highly resolved HSQC spectrum was reconstructed from 5.12% of the data. Moreover, reconstructed 2D HSQC-TOCSY spectrum yielded information about the correlations within one sugar unit, and 2D HSQC-NOESY technique allowed the sequential assignment of the glucosidic units.