Comparison of the Efficiency of Different Extraction Methods on Antioxidants of Maltease Orange Peel

Affiliation

¹UR11ES44, Ecophysiology and Agri Processes, Higher Institute of Biotechnology of Sidi Thabet, University of Manouba, BP-66, 2020 Ariana-Tunis,Tunisie

²Lorraine University, ENSAIA- Biomolecular Engineering Laboratory (LIBio), 2 avenue de la Forêt de Haye, TSA 40602 Vandoeu vre Cedex 54518, France

Abstract

The effect of conventional solvent extraction, CSE, ultrasound assisted extraction, UAE, microwave assisted extraction, MAE and supercritical CO₂ extraction, SC-CO₂ on the total phenols content, total flavonoids, individual flavonoids and antioxidant activity of orange peel were compared. Neohesperidin (from 0.624 ± 0.013 for SC-CO₂ extraction to 1.045 ± 0.001 g100 g orange peel powder for MAE) and hesperidin (from 0.407 ± 0.008 for SC-CO₂ extraction to 0.836 ± 0.029 g/100 g orange peel powder for UAE) are the major flavonoids (80% of total flavonoids by MAE and 87% by CSE) of orange peel whatever the used extraction method. The method giving the highest total phenol and flavonoid contents is microwave assisted extraction (2.363 ± 0.014 g GAE/100g orange peel powder), followed by ultrasound assisted extraction, conventional solvent extraction, and supercritical CO₂ extraction. However, antioxidant activity (DPPH method) cannot be correlated to TPC, TFC or individual flavonoids. Orange peel extracted by CSE (ethanol (80%), m/v: 5 g: 50 ml, 30 min, 35°C, mechanical stirring at darkness, 3 successive extractions) presents the higher radical scavenging capacity compared to the other extracts obtained by MAE (Ethanol (80%), m/v: 5 g: 50 ml, 10s, 35°C, 170 W, 3 successive extractions) and UAE (ethanol (80%), m/v: 5g: 50 ml, 30 min, 35°C, magnetic stirring at darkness, 3 successive extractions, 125 W), SC-CO₂ extraction (ethanol (80%), m/v:5 g: 50 ml, 30 min, 35°C, 22 MPa, 3 successive extractions). Besides, no additivity on the antioxidant activity is found with the DPPH method.