Composition of free and glycosidically bound volatiles of Mentha aquatica L.

Free and glycosidically bound volatiles of Mentha aquatica L. were investig ated. Free volatile compounds were isolated from the dried plant material b y hydrodistillation and glycosides by extraction with water during hydrodis tillation. Free volatile compounds (essential oil) as well as the aglycones obtained after the hydrolysis of glycosides were analyzed by gas chromatog raphy-mass spectrometry (GC-MS). The essential oil was composed of monoterp ene hydrocarbons (10.47%), sesquiterpene hydrocarbons (20.09%) and oxygen c ontaining compounds (68.42%). The major components of the essential oil wer e: menthofuran (3978.08 mg kg(-1)), 1,8-cineole (1716.44 mg kg(-1)) and tra ns-caryophyllene (1109.20 mg kg(-1)). After enzymatic hydrolysis, the major volatile aglycones were: 1-octen-3-ol (30.22 mg kg(-1)), eugenol (10.21 mg kg(-1)), 2-phenylethanol (6.81 mg kg(-1)), 3-hexen-1-ol (5.35 mg kg(-1)), perilla alcohol (4.13 mg kg(-1)), 1-hexanol (3.58 mg kg(-1)), and 3-octanol (2.44 mg kg(-1)). Moderate similarity was found between volatile aglycones and the corresponding free volatiles in the essential oil. Acidic hydrolys is, after enzymatic hydrolysis, liberated additional amounts of aglycones. Approx. 38% of the glycosides were not hydrolyzed by the used enzyme.