Basic Concepts of Metabolomics and Application to the Food and Nutrition Science

NMR spectroscopy is widely used to investigate living systems mainly for two reasons: i) it is usually regarded as the universal detector for practically all organic substances of natural origin, because it quantitatively records signals for all substances containing hydrogen atoms above the micromolar concentration limit, and ii) the spectrum obtained under controlled experimental conditions (temperature and pH) is highly reproducible so that it is suitable, as it is, for direct multivariate data analysis. For this reason, the NMR spectrum of the cell extract is generally regarded as the metabolic profile of an organism, and from these premises metabolomics has been developed based on the chemometrics analysis of NMR spectra of biological samples, including tissues and cell extracts. The approach allows a measure, against a control population, of the perturbations induced by a treatment, through a holistic view of the cellular composition. Subsequently, the identification of the metabolites contributing to the description of the perturbation is also possible. NMR spectroscopy, thus, is increasingly used in the investigation on the metabolic effects of natural molecules with bacteriostatic and/or bactericidal actions on bacterial growth. The presentation will provide an overview on the methodology, discussing limits and advantages of NMR in the metabolomics approach, and will present possible applications for the evaluation of food transformations during processing, storage and digestion.