Non-targeted NMR approach to unveil and promote the biodiversity of globe artichoke in the Mediterranean area

The globe artichoke is an important constituent of the Mediterranean diet, being rich in bioactive compounds. Artichoke is widely cultivated in Italy, especially in the Apulia region, with a multitude of local varieties. Most of this genetic material is endangered and its metabolic profile is not yet characterized. In this work, we aimed at dissecting landrace biodiversity by characterizing the metabolic profiles of edible hearts, i.e. the edible inner part of the flower heads, and external bracts of artichoke flower heads, using a simple, fast, and affordable analytical methodology. A non-targeted spectroscopic approach combining NMR experiments and multivariate data analysis provided a comprehensive picture of the chemical composition of 16 artichoke landraces, some of which are at risk of extinction. A special focus was on hydrosoluble compounds, contributing to the functional food value of the artichoke. Moreover, a possible correlation between the metabolic composition and the head color was established. Our analyses highlight the nutraceutical diversity and value of newly studied artichoke landraces. Specifically, the hearts of the deep purple-colored "Nero del Salento" are rich in both mono- and dicaffeoylquinic acids along with inulin, while the hearts of the green "Bianco di Taranto" and "Centofoglie di Rutigliano" are characterized by a relatively higher content of dicaffeoylquinic acids. The results can help promote endangered local varieties for production and commercialization, against the ongoing genetic erosion and loss of crop diversity.