Abstract
Ultrasound assisted extraction (UAE) of antioxidant polyphenols from Aronia melanocarpa berries was studied. The influence of various parameters (time and temperature of extraction, solvent composition, solid-solvent ratio, particle size, and ultrasonic irradiations) on the extraction kinetics and yields was evaluated. Very clear effect of ultrasound was observed (up to 85% increase of the yield of extracted polyphenols). High temperature and the presence of ethanol in the solvent improved also greatly the extraction process. The high antioxidant activity of the extracts determined by DPPH tests confirmed suitability of UAE for the preparation of antioxidant-rich plant extracts. A very good correlation between the concentration of polyphenols in the extracts and the corresponding antioxidant activity was observed. (C) 2012 Elsevier BM. All rights reserved.