Optimization of the solid-liquid extraction process of phenolic compounds from mulberry fruit

Abstract

The study was designed to examine the influence of solvent concentration (ethanol/water 20-80% by volume), extraction time (15-240 min) and extraction technique on the extraction yield of phenolic compounds, flavonoids and antioxidant activity from Morus nigra L., Morus rubra L. and Morus alba L. fruits. The optimum conditions for the extraction of total phenols, flavonoids and monomeric anthocyanins by the maceration and ultrasonic extraction processes were: 213.6 min with 80% ethanol, and 182.1 min and 71.2% ethanol, respectively (black mulberry), and 216.5 min with 78.3% ethanol and 198.7 min and 70.6% ethanol, respectively (red mulberry). In case of white mulberry for the extraction of total phenols and flavonoids optimum extraction conditions (maceration and ultrasonic) were 232.7 min and 80% ethanol, and 187.2 min and 68.7% ethanol, respectively (white mulberry). Obviously, ultrasonic extraction was less time consuming, and it requires for all performed extractions solvent with less percentage of ethanol.