*2.2. Purification and Fractionation of PPC by a Sephadex LH-20 Column*

The PPC was fractionated with a Sephadex LH-20 column, according to a means expounded in the literature, with certain modifications [8,19]. A total of 6 g of proanthocyanidin sample was dissolved in a methanol/water solution with the volume ratio of 1:1 and loaded in a Sephadex LH-20 column that was pretreated. Then, the pillar was washed with 50% methanol until the eluent became colorless to clear other phenolic substances, glycosides, and some flavan-3-ol monomers. The column was then developed with the sequence of acetone/methanol/water solutions (respectively, 2:5:3, 4:3:3, and 7:0:3 *v/v/v*), and the volume of all solvent mixtures was 600 mL. The grading elutions were named as fraction 1, 2, and 3, respectively. Then, the organic solvents of these fractions were removed by vacuum rotary evaporation and lyophilized to drying. The obtained components were, respectively, labeled PPC1, PPC2, and PPC3.
