Polyphenol profile and antioxidant activity of extracts from olive leaves

The compounds, derivatives of olive leaves have a high antioxidant activity. The content of the total phenolic compounds (TPC), antioxidant activity (AOA) and HPLC polyphenol profile of methanol extracts from the leaves of the olive cultivars Chondrolia Halkidiki, Kalamon, Koroneiki grown in the nursery (in vivo) and in vitro plants of Chondrolia Halkidiki were compared. The results obtained for TPC varied between 9.2±0.5 mgGAE*gDW-1 and 16.4±0.5 mgGAE*gDW-1 . Antioxidant capacity was determined by four methods DPPH, ABTS, FRAP and CUPRAC. The highest results for TPC and AOA were achieved for the leaves of Chondrolia Halkidiki grown in vitro. A high correlation between the results gained from the TPC and AOA was established. Conducted HPLC analysis revealed the presence of 3,4- dihydroxybenzoic, caffeic, sinapic and ferulic acids and quercetin, hesperidin and luteolin and the quercetin glycosides rutin and hyperoside.