TOTAL PHENOLIC CONTENT, PHENOLIC PROFILE AND ANTIOXIDANT ACTIVITY IN LEAVES AND DRUPES OF GREEK OLIVE CULTIVARS

Ten Greek olive cultivars, ‘Koroneiki’, ‘Lianolia Kerkyras’, ‘Mastoidis’, ‘Arbequina’, ‘Adramytini’, ‘Megaritiki’, ‘Gaidourelia’, ‘Kalamon’, ‘Konservolia’ and ‘Chalkidiki’, were studied in order to determine the phenolic profile, the phenolic content, and the antioxidant activity, both in leaves and drupes (green and black) in each cultivar. Total phenolic content, in new season leaves, ranged between 1.01 mg GAE/g (‘Adramytini’) and 2.06 mg GAE/g (‘Konservolia’), while the antioxidant activity ranged between 157.64 ppm (‘Konservolia’) and 285.80 ppm (‘Adramytini’). In green drupes, total phenolic content ranged between 0.59 mg GAE/g (‘Megaritiki’) and 1.98 mg GAE/g (‘Mastoidis’) while the antioxidant activity ranged between 119.66 ppm (‘Lianolia Kerkyras’) and 496.45 ppm (‘Megaritiki’). Total phenolic content in black drupes ranged between 0.54 mg GAE/g (‘Gaidourelia’) and 0.99 mg GAE/g (‘Lianolia Kerkyras’), while the antioxidant activity ranged between 284.23 ppm (‘Lianolia Kerkyras’) and 886.36 ppm (‘Chalkidiki’). The HPLC analysis showed the presence of flavonoids, hydroxy-cinnamic derivatives and secoiridoids. In leaves the most abundant compounds were oleuropein, luteolin-7-o-glucoside and rutin while luteolin-4-o-glucoside, hydroxy-tyrosol and caffeic acid were detected in lower amounts. In drupes the most abundant compounds were verbascoside and oleuropein.