Optimization of Microwave‐Assisted Extraction of Anthocyanins from Mulberry and Identification of Anthocyanins in Extract Using HPLC‐ESI‐MS

Anthocyanins are naturally occurring compounds that impart color to fruits, vegetables, and plants. This study aims to optimize the microwave-assisted extraction (MAE) conditions of anthocyanins from mulberry (M. atropurpurea Roxb.) using response surface methodology (RSM). A Box-Behnken experiment was employed in this regard. Methanol concentration, microwave power, and extraction time were chosen as independent variables. The optimized conditions of MAE were as follows: 59.6% acidified methanol, 425 W power, 25 (v/w) liquid-to-solid ratio, and 132 s time. Under these conditions, 54.72 mg anthocyanins were obtained from 1.0 g mulberry powder. Furthermore, 8 anthocyanins were identified by high-performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS) in mulberry extract. The results showed that cyanidin-3-glucoside and cyanidin-3-rutinoside are the major anthocyanins in mulberry. In addition, in comparison with conventional extraction, MAE is more rapid and efficient for extracting anthocyanins from mulberry.