Optimization and kinetic modelling of microwave-assisted extraction of phenolic contents and antioxidants from Turkish artichoke

Abstract

Replacing traditional extraction technology with ultrasonic or microwave-assisted extraction has attracted considerable attention. In order to maximize the yield of extracted polyphenolic compounds and antioxidants from Sakiz artichoke by-products, a central composite design (CCD) was applied to optimize the microwave-assisted extraction (MAE) in the current study. The study found that the optimal conditions for MAE of Sakiz artichoke by-products were: extraction time 6 min; ethanol/water ratio 50:50 (v/v); (ethanol-water)/solid ratio 15:1 mL/g; microwave power 320 W; and temperature 80°C; resulting in the total phenolic compounds (TPC), DPPH, and CUPRAC antioxidant activity values of 607 mg GAE/100 g, 878 mg TE/100 g, and 2922 mg TE/100 g, respectively. The extraction of TPC, DPPH, and CUPRAC antioxidants from artichoke by-products was investigated by the first-order, second-order, Peleg’s, and Page’s kinetic models. These results confirmed that MAE has a great potential for the extraction of polyphenolic compounds and antioxidants from Sakiz artichoke by-products.