Abstract—The objective of this study was to optimize the extraction conditions for phenolic compounds, total flavonoids, and antioxidant activity from Deglet-Nour variety. The extraction of active components from natural sources depends on different factors. The knowledge of the effects of different extraction parameters is useful for the optimization of the process, as well for the ability to predict the extraction yield. The effects of extraction variables, namely types of solvent (methanol, ethanol and acetone) and extraction time (1h, 6h, 12h and 24h) on phenolics extraction yield were evaluated. It has been shown that the time of extraction and types of solvent have a statistically significant influence on the extraction of phenolic compounds from Deglet-Nour variety. The optimised conditions yielded values of 80.19 ± 6.37 mg GAE/100 g FW for TPC, 2.34 ± 0.27 mg QE/100 g FW for TFC and 90.20 ± 1.29% for antioxidant activity were methanol solvent and 6 hours of time. According to the results obtained in this study, Deglet-Nour variety can be considered as a natural source of phenolic compounds with good antioxidant capacity. Keywords—Deglet-Nour variety, Date palm Fruit, Phenolic compounds, Total flavonoids, Antioxidant activity, Extraction, Optimization. I. INTRODUCTION ATE, fruit of the date palm (Phoenix dactylifera L.), very exploited in Mediterranean Africa, especially in the Algerian south, constitute an essential food for Muslims during all seasons, notably in the holy month of Ramadan. Date palm fruits have been an important component of the diet in most of the arid and semiarid regions of the world. Several studies indicate that consumption of fruits and vegetables reduces the risk of several chronic diseases: coronary heart disease, blood pressure, obesity, diabetes and cancers [1], [2]. Dietary phenolic compounds and flavonoids have generally been considered, as non-nutrients and their possible beneficial effect on human health have only recently been recognized. These compounds are secondary metabolites that gather a large set of molecules, divided into fourteen chemical classes [3]. These valuable molecules possess very interesting biological properties, which are used in various fields, such as medicine, pharmacy and nutrition. A. Lekbir, O. Alloui-Lombarkia, Y. Noui, and S. Baississe are with the Department of Food Technology, food science laboratory, University of Hadj Lakhdar-Batna, Algeria (e-mail: lekbiradel@yahoo.fr, ouridaa@hotmail.com, noui.yassine@gmail.com, baississe.nourhane@yahoo.fr). S. Mekentichi was with the Department of Food Technology, food science laboratory, University of Hadj Lakhdar-Batna, Algeria (e-mail: mekentichisihem@yahoo.fr). Extraction is an important step in the isolation and later in the identification and quantification of phenolic compounds; it is very difficult to develop a standardized extraction method that would simultaneously extract all phenolic compounds [4]. The extraction parameters may affect the quality and quantity of antioxidant activity. Many factors, such as solvent composition, the extraction time, temperature, pH, liquid-solid ratio and particle size, may significantly influenced the liquid- solid extraction. The extraction and purification of bioactive compounds from natural sources has become very important for the utilization of phytochemicals in the preparation of dietary supplements or nutraceuticals, functional food ingredients, and additives to food, pharmaceutical and cosmetic products [5]. The purpose of the present study was to examine the influence of extraction conditions (solvent type and extraction time) on extractability of phenolic compounds from Deglet- Nour variety, and to measure the antioxidant capacity of resultant extracts. II. MATERIAL AND METHODS A. Plant Material The variety of date palm fruit used in this study is semi-soft date namely Deglet-Nour date (moisture content 26%). This variety was purchased from a local fruit supplier in Batna, Algeria. The samples were selected identically in terms of size, colour, ripening stage, without damaged and calamity, and were stored in paper bags at 4°C until use. B. Chemicals and Standards Acetone, ethanol, methanol, gallic acid, quercetin, Folin- Ciocalteu’s reagent, sodium carbonate, aluminum chloride and DPPH (2,2-diphenyl-1-picryhydrazyl). All chemicals were purchased from Sigma-Aldrich (USA), Fluka Chemie (Switzerland) and Merck (Germany). All Chemicals and reagents used were of analytical grade. C. Moisture Content Moisture was determined according to standard AOAC méthod 920.151 [6]. D. Extraction of the Phenolic Compounds After cleaning and pitting dates, maceration was carried out on 1g of crashed pulp with 40ml of solvent at room temperature during different times with continued agitation. After centrifugation and filtration, the extracts were concentrated under reduced pressure at 40°C in a rotary evaporator. The extracts were kept in dark glass bottles inside the freezer until use. The storage conditions (time and Lekbir Adel, Alloui-Lombarkia Ourida, Mekentichi Sihem, Noui Yassine, Baississe Salima Optimization of Deglet-Nour Date (Phoenix dactylifera L.) Phenol Extraction Conditions D World Academy of Science, Engineering and Technology International Journal of Nutrition and Food Engineering Vol:7, No:11, 2013 1023 International Scholarly and Scientific Research & Innovation 7(11) 2013 scholar.waset.org/1307-6892/17259 International Science Index, Nutrition and Food Engineering Vol:7, No:11, 2013 waset.org/Publication/17259