Authors:
Barakat, O. M., Badr, M. R. Elsebaie, E. M., Salem, M. A
Volume 30, Issue 1;
Pages: 66-75; 2024
ISSN: 2069-0053 (print), Agroprint;
ISSN (online): 2068-9551
The influence of temperature (40 - 50°C), extraction duration (60-180 minutes), and liquid (ethanol 70%) to solid ratio (10-25 ml/g, solvent volume per g of raw material) on extractability of total phenolics and antioxidant activity of iceplant were examined. Response surface method was used to identify the best extraction conditions for the phenolics and antioxidant activity. The Central Composite Design revealed that polynomials predictive models were in good agreement with the experimental data, with correlation coefficients of 0.9476, 0.8783, 0.9646, and 0.8711 for total phenolics, DPPH, ABTS, and reducing power (RP), respectively. The optimum conditions were a ratio of 15.469 mL/g liquid (ethanol 70%) to solid, an extraction period of 120 minutes, and a temperature of 40 °C. Under optimised conditions, high levels of total phenolic compounds (9.45 mg GAE g -1) were produced, as well as high levels of DPPH (88.17%) and ABTS (57.15%) free radical scavenging ability and reducing power (15.1 mg ascorbic acid/g extract). The experimental results coincided with those predicted, showing that the utilised model was appropriate and that the response surface method was successful in optimising the extraction parameters of the examined system. This is the first publication on optimising the extraction method of phenol components and the antioxidant activity of iceplant.