The fractions of the cell wall,
organelle, and cytoplasm of tea roots and leaves were isolated
according to the methods proposed by Weigel and Jager.22 In brief,
100 pieces of 10 mm tea root tips or 2.0 g of tea leaves was
homogenized using a mortar and pestle in a medium containing 250
mM sucrose, 50 mM Tris-HCl (pH7.5), and 1 mM dithiothreitol. All
the steps were performed at 4 °C.