Volatile Constituents of Two Croton Species from Caatinga Biome of Pernambuco-Brasil

Leaf and stem essential oils from Croton pulegioides Mull. Arg. and C. rhamnifolius var. heliotropiifolius (Kunth) Mull. Arg were obtained by hydrodistillation and analyzed using gas chromatography and gas chromatography-mass spectrometry. The composition of the oils from the two Croton species was very different. The main components of the C. pulegioides oils were 1,8-cineole (15.86+/- 0.23% in leaf), p-cymene (14.40+/- 0.01% in leaf), camphor (13.28%+/- 0.12% in leaf) and alpha-humulene (12.98+/- 0.22% in leaf), alpha-calacorene (12.95+/- 0.45% in stem), cis-isolongifolane (8.94+/-0.54% in stem) and juniper camphor (6.44+/-0.45% in stem). The main components of the C. rhamnifolius var. heliotropiifolius oils were beta-caryophyllene (20.820+/-0.48% in leaf), spathulenol (16.37+/-0.56% in leaf) and beta-elemene (17.28+/-0.06% in stem) and guaiol (18.38+/-0.84% in stem). Phenylpropanoids common to Croton species were only found in C. rhamnifolius var. heliopropiifolius oils at percentages below 5%. This is the first report of the essential oil constituents of C. pulegioides and C. rhamnifolius var. heliotropiifolius from the Caatinga biome of the state of Pernambuco (Northeastern Brazil).