in this work, the volatile compounds extracted by simultaneous distillation and extraction as well as the volatile constituents by solid phase micro-extraction (spme) from different structures (in vitro and ex vitro roots, leaves, and inflorescence) of petiveria alliacea were analyzed by gc/fid and gc/ms. forty-one different compounds were identified. differences were observed between plant structures and origin (either in or ex vitro). however, sulfur compounds were common to all samples, like bis(phenyl-methyl)-disulfyde, isothiazole (1,2-thiazole), 2-thiopropane, dimethyl sulphyde, ethylene disulfyde, and 2,3-dimethyl-thiirane. in vitro plant roots exhibited higher chemical diversity among the analyzed plant structures. substances found in all analyzed structures of p. alliacea by spme were benzaldehyde, calamenene and the hydrocarbons dodecane, tridecane, and tetradecane.