Influence of genotype, harvest time and plant part on polyphenolic composition of globe artichoke [Cynara cardunculus L. var. scolymus (L.) Fiori]

Globe artichoke is an ancient herbaceous plant native to the Mediterranean Basin. The edible part of the plant (head) is particularly rich in polyphenols, whose therapeutic properties are well documented. A field experiment was conducted in Sicily (south Italy) to examine the influence of genotype and harvest time on the polyphenol content and profile of different head parts. The concentrations of 19 phenolic compounds were determined by HPLC-DAD-ESI/MSn analysis. It was observed that individual phenolic substances were preferentially accumulated in specific head parts and genotypes. Apigenin 7-O-glucuronide was found to be the major flavonoid, with 6298 mg kg(-1) DM in 'Romanesco clone C3' receptacle, whereas chlorogenic acid represented the main caffeoylquinic acid, reaching 14841 mg kg(-1) DM in the inner bracts of 'Violetto di Sicilia'. Our findings prove also the influence of climatic conditions on the phenolic profile and thus suggest giving specific consideration to harvest time. (C) 2009 Elsevier Ltd. All rights reserved.