In the globe artichoke, both the edible portion and the waste biomass are recognized as valuable sources of bioactive compounds. For this study, heads with 30 cm-long floral stems including two to three leaves were harvested from five genotypes, which included two traditional vegetative-propagated varietal types ("Brindisino" and "Violetto di Foggia") and three "seed"-propagated hybrids ("Tempo", "Opal", and "Madrigal"). The study aimed to determine the total and individual polyphenolic concentrations (measured spectrophotometrically and using HPLC) and antioxidant activity (AA) in different artichoke parts, namely the "hearts" (H), head waste (HW), stem waste (SW), and leaf waste (LW). "Brindisino" SW exhibited the highest accumulation of luteolin (26,317 mg kg-1 F.W.), while "Tempo" H displayed the highest cynarin content (190 mg kg-1 F.W.). "Tempo" HW and H showed the highest levels of apigenin (640 mg kg-1 F.W.), and the greatest source of chlorogenic acid was found in the HW of "Opal" and the H of "Brindisino" (4300 mg kg-1 F.W.). The hybrids generally exhibited lower total polyphenolic concentrations than the traditional genotypes, particularly evident in the LW. The SW demonstrated the highest concentration of total polyphenols (18,000 mg kg-1 F.W.), followed by the edible H and non-edible HW (12,000 mg kg-1 F.W.), while the LW exhibited the lowest concentration (2000 mg kg-1 F.W.). Interestingly, the AA did not precisely align with the total polyphenolic concentration, showing slight variations between the examined parts and genotypes.
Keywords: Brindisino; Cynara cardunculus L. subsp. scolymus; Madrigal; Opal; Tempo; Violetto di Foggia; apigenin; chlorogenic acid; cynarin; luteolin; polyphenols.