Effects of oleuropein-rich olive leaf extract on the oxidative stability of refined sunflower oil





Antioxidants, Oils oxidative stability, Oleuropein, Olive leaf extract


The aim of this study is to investigate the ability of oleuropein-rich olive leaf extract (OLE) to improve the quality and oxidative stability of sunflower oil subjected to accelerated thermal oxidation. Oleuropein was the major phenolic compound determined by HPLC-DAD with a content ranging from 20.81 to 32.56 mg·g-1 of dry extract (DE). The evaluation of the in vitro antioxidant capacity of OLE showed good scavenging capacity of the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) and hydrogen peroxide (H2O2) (1.01 and 0.96 mmol Trolox equivalents (ET·g-1 DE, respectively). The enrichment of sunflower oil with 0.1, 0.25 and 0.5% OLE (w/v) significantly inhibited thermal-induced peroxidation in a dose-dependent fashion. 0.25% OLE was the most effective concentration and showed a significant reduction in peroxide value and conjugated dienes by 61.4 and 17.4%. These results indicate that OLE can be considered a good natural alternative for extending the shelf-life of polyunsaturated vegetable oils.


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How to Cite

M’Rabet Y, Hosni K, Khwaldia K. Effects of oleuropein-rich olive leaf extract on the oxidative stability of refined sunflower oil. grasasaceites [Internet]. 2023May26 [cited 2023May28];74(2):e505. Available from: https://grasasyaceites.revistas.csic.es/index.php/grasasyaceites/article/view/1985