Metabolomics and antioxidant activity of the leaves of Prunus dulcis Mill. (Italian cvs. Toritto and Avola).

Prunus dulcis leaves have been reported to exert some biological activity, in particular potent free radical-scavenging capacity, but so far there is limited information on their chemical composition. With the aim to achieve deep insight on the chemical constituents of the leaves of P. dulcis cultivars "Toritto" and "Avola", the most appreciated in Italy, an approach based on liquid chromatography-mass spectrometry (LC-MS) combined with isolation and structure elucidation of pure compounds by Nuclear Magnetic Resonance (NMR) analysis was carried out. Results allowed to detect in cv. Toritto leaves phenolics, terpenoids and a cyanogenic glycoside. Successively, various solvent systems were chosen to afford different extracts and an approach based on principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) from LC-MS data sets highlighted eco-friendly methods as selective in extracting phenolics and glycosides. Comparison of LC-MS profiles of the MeOH extracts of cv. Toritto and cvs. Avola (Pizzuta, Fascionello and Romana) leaves and evaluation of their phenolic contents and antioxidant activity were also carried out.