 Corresponding author: Leila Derradji Department of Pharmacy, Faculty of Medicine, Badji Mokhtar-Annaba University, Algeria. Copyright © 2022 Author(s) retain the copyright of this article. This article is published under the terms of the Creative Commons Attribution Liscense 4.0. Determination of polyphenolic components by High Performance Liquid Chromatography (HPLC) and evaluation of the antioxidant activity of leaves of Olea europaea L. var. sylvestris (Miller) Lehr Amel Zighed 1 , Leila Derradji 1, * and Youcef Hadef 2 1 Department of Pharmacy, Faculty of Medicine, Badji Mokhtar-Annaba University, Algeria. 2 Laboratory of Development and Control of Pharmaceutical Preparations, Department of Pharmacy, Faculty of Medicine, Badji Mokhtar-Annaba University, Algeria. GSC Biological and Pharmaceutical Sciences, 2022, 20(01), 095–099 Publication history: Received on 02 June 2022; revised on 06 July 2022; accepted on 08 July 2022 Article DOI: https://doi.org/10.30574/gscbps.2022.20.1.0281 Abstract Olea europaea L. var. sylvestris (Miller) Lehr is an inseparable entity of the Mediterranean people, used in traditional medicine for its many therapeutic virtues.Its leaves are rich in polyphenols.In the present study we wanted to research its polyphenolic components in which it is rich. The method we used is high performance liquid chromatography (HPLC) and evaluation of the antioxidant activity in the methanolic extract of its leaves. For this evaluation we followed the free radical reduction method DPPH (2, 2-diphenyle-1-picryl hydrazyl) by an antioxidant. The results show, the presence of polyphenolic components such ascaffeic acid, chlorogenic acid and rutin, and significant antioxidant activity. Olea europaea L. var. sylvestris (Miller) Lehr is could be placed as an alternative treatment for certain pathologies because it is of value for public health. Keywords: Olea europaea L. var. sylvestris; Leaves; Methanolic extract; Polyphenolic components; Antioxidant activity 1. Introduction Olea europaea var. sylvestris is used in traditional medicine for its therapeutic properties. It has been used in traditional medicine to treat hypertension and diabetes [1]. It has also been widely used as a remedy for the treatment of fever and other diseases such as malaria [2]. The activity of standardized extract has been demonstrated in numerous in vitro or in vivo experiments [3]. The leaves of Olea europaea var. sylvestris are rich in polyphenolic components, mainly oleuropein, hydroxytyrosol and other flavonoids [4]. The present study aims to determine these polyphenol components by high performance liquid chromatography (HPLC) and to evaluate the antioxidant activity of the leaves of this plant. The method that we have recommended is that of the reduction of the free radical DPPH (2, 2-diphenyle- 1-picryl hydrazyl) by an antioxidant (anti-free radical). The results show the presence of polyphenolic components such as caffeic acid, chlorogenic acid and rutin and significant antioxidant activity. Olea europaea var. sylvestris, whose pharmacological properties have given it a good place in traditional medicine, could be placed as an alternative treatment against certain pathologies because it is of value for public health.