Annals of the University Dunarea de Jos of Galati. Fascicle VI: Food Technology (Mar 2018)
Optimized ultrasonic-assisted extraction of total phenolics and antioxidant activity of date (Phoenix dactylifera l.) using response surface methodology
Abstract
In the present study, we have optimized the ultrasonic-assisted extraction conditions of total phenolic compounds (TPC) and antioxidant activity of date fruit using response surface methodology (RSM). Three factors including methanol concentration (40- 80%), sonication amplitude (50-100%) and extraction time (10-30 min) were investigated. The analysis of results with JMP software, using Box-Behnken model, indicated that 65% methanol, ultrasound amplitude of 84.50%, and of extraction time of 17.64 min were the optimal combination that maximized antioxidants extraction. Under the optimized conditions, the experimental values for both TPC and antioxidant activity were 246.46 mg EAG/100g and 26.48 mg EAG/100g, respectively. Predicted models were highly significant (P < 0.01) with high regression coefficients (R2 ≥ 0.97), while the lack of fit is insignificant. RSM was shown to be an adequate approach for modeling the total phenolic extraction and the antioxidant activity of date palm fruit.
