Similarity and differential NMR spectroscopy in metabolomics: application to the analysis of vegetable oils with 1H and 13C NMR.

Abstract

In NMR based metabolomics there is a need for tools to easily compare spectra and to extract the maximum of information from the data. The calculation of similarity and performing differential NMR spectroscopy provides important additional information for classification and validation in metabolomics experiments. From 13 different vegetable oils samples were analysed by 1H and 13C NMR. The similarity between spectra was calculated and differential NMR spectroscopy was used to discover marker compounds. The similarity between the individual spectra was calculated for the spectra of all samples. The similarity was used to verify and improve the alignment. For vegetable oils which showed a high similarity, e.g. chia seed oil and linseed oil, differential NMR spectroscopy was used to discover marker compounds. The calculation of similarity is an important tool to reveal variability between samples and spectra and can be used to verify data sets and improve alignment or binning procedures. With differential spectroscopy marker compounds are easily discovered. The methods can be seen as an important addition to the routine procedures of metabolomics experiments.