Optimization of the Extraction of the Total Phenolics and Antioxidant Compounds from Solanum nigrum Fruit using Response Surface Methodology

Subject Areas : Microbiology

F. Khanlari ¹ (دانش‌آموخته کارشناسی ارشد، گروه علوم و صنایع غذایی، دانشکده کشاورزی، واحد یزد، دانشگاه آزاد اسلامی، یزد، ایران)
A. Yasini Ardakani ² (استادیار گروه صنایع غذایی، واحد یزد، دانشگاه آزاد اسلامی، یزد، ایران)
N. Nasirizadeh ³ (استادیار گروه صنایع غذایی، واحد یزد، دانشگاه آزاد اسلامی، یزد، ایران)

Received: 2016-05-14 Accepted : 2016-05-14 Published : 2016-05-21

Keywords: Antioxidant Activity, Optimization, RSM, Solanum nigrum, Total Phenolics,

Abstract :

Introduction: Solanum nigrum L. (SN) is a herbal plant indigenous to the north-east of Asia. The plant is believed to have various biological activities. In this study, the optimum conditions for the extraction of phenolic compounds from Solanum nigrum were determined using response surface methodology (RSM). Materials and Methods: Extraction was carried out using different solvents in order to determine the best solvent for the highest extraction yield. Central composite design was employed to optimise the three independent variables such as incubation temperature (25–70 ºC), time (30–240 min) and liquid-to-solid ratio (10–20 ml/g). Total phenols (TP) was measured using Folin – Ciocalteu method and IC50 scavenging activity was analyzed using DPPH method. Results: The preliminary experiments with p<0.05 showed that ethanol was the best solvent for the extraction of Solanum nigrum. The experimental data were fitted into a second-order polynomial equation and 3D response surfaces showed that the optimal conditions were at the temperature of 70 ºC, time of 30 min and liquid to solid ratio of 20 ml/g. These optimum conditions obtained the total phenolic compounds of 18.04 mg gallic acid equivalents/100 g and DPPHsc of 61.9 μg/ml. Conclusion: The result of this study indicated the suitability of the response surface methodology employed in optimizing the extraction conditions. The optimized conditions showed a fast and high extraction yield of phenolic and antioxidant compounds from Solanum nigrum.