Extraction and Characterization of the Phenolic Compounds from Leaves of Olea Europaea L. via Ple

Abstract

Oleuropein is the predominant phenolic compound in olive leaves. It presents high antioxidant and anti-inflammatory activities and has antimicrobial action. The objective of this study was to extract the phenolic compounds from dried olive leaves using pressurized ethanol in a continuous flow and characterize them. The flow rate (0.5 to 1.0 mL min^-1), temperature (30 to 60 °C) and pressure (10 to 20 MPa) were the operational parameters. The results showed that the temperature was a significant factor in the yield of the extracts, with higher yields at the highest temperature. The oleuropein content in the extracts ranged from 80.5 to 82.9 mg g^-1, and the extract presented different classes of compounds. The total phenolic components were in the range of 10.5 to 12.8 mg GAE g^-1 of extract. The best condition to obtain an extract with the highest yield and total phenolic compounds, and suitable oleuropein content and antioxidant capacity was 60 °C, 10 MPa and 0.5 mL min^-1