Distribution of oleanolic acid glycosides in vacuoles and cell walls isolated from protoplasts and cells of Calendula officinalis leaves.

The contents of oleanolic acid and its 3-0-glucuronide derivatives as well as of 3-0-glucoside derivatives were determined in vacuoles prepared from protoplasts and cell walls obtained from cells of Calendula officinalis leaves. In both cell compartments studied 37% of total cellular oleanolic acid were accumulated, 0.6% occurring as free oleanolic acid (only in vacuoles). Glucuronides accounted for 31.1% (20.7% in vacuoles and 10.4% in cell walls), and glucosides for 5.3% (2.6% in vacuoles and 2.7% in cell walls).