*3.1. Chemicals*

Sucrose, formic acid, DMSO, and sodium phosphate were purchased from Sigma-Aldrich Co., LLC (St. Louis, MO, USA). Daidzin, glycitin, genistin, daidzein, glycitein, and genistein were bought from Extrasynthese (Genay, France). Malonyldaidzin, malonylglycitin, malonylgenistin, acetyldaidzin, acetylglycitin, and acetylgenistin were purchased from Wako Chemical Co. (Tokyo, Japan). HPLC-grade water, acetonitrile, and methanol were obtained from Fisher Scientific (Hampton, NH, USA). All other chemicals used in this study were of analytical reagent grade.
