chemical composition of the essential oils extracted from the leaves, stems, flowers and seeds of  heracleum rechingeri manden. were analyzed by gc and gc/ms. twenty-four components were characterized for the leaf oil with octyl acetate(47.2%), octanol(15.2%) and e-caryophyllen (5.7%) as the main constituents. 25 compounds were identified in the stem oil with elemicin (65.3%), octyl acetate (13...