Antioxidant capacity of crude extracts and their solvent fractions of selected Algerian Lamiaceae

The present study was carried out to evaluate the antioxidant capacity of the aerial parts of ethanol crude extracts and their four solvent fractions (hexane (HF), ethyl acetate (EAF), butanol (BuOHF), and aqueous (WF)) of three selected Algerian Lamiaceae: Calamintha clinopodium, Teucrium flavum and Thymus algeriensis. The extracts of the three Lamiaceae were evaluated for their total phenols, flavonoids, flavonols content and antioxidant activity (reducing power, total antioxidant capacity, DPPH radical and hydrogen peroxide scavenging effect). WF of T. algeriensis was the most effective fraction with 75.13 mg ascorbic acid equivalent (AscA E)/g of powder for reducing power, and 218.37 mg(AscA E)/g of powder for total antioxidant activity. It also showed the highest DPPH and hydrogen peroxide scavenging capacities with IC50 values of 0.01 and 0.08 mg/mL, respectively. Moreover, WF of T. algeriensis exhibited higher total phenolic content (99.21 mg gallic acid equivalent (GAE)/g of powder). Aqueous fraction of T. algeriensis has a strong ability to act as antioxidant, and may be considered as a natural source of active compounds. (C) 2013 Elsevier B.V. All rights reserved.