Free and glycosidically bound volatiles of <i>Mentha citrata</i> Ehrh.

Free and glycosidically bound volatiles of surficial parts of Mentha citrata were investigated. Free volatile compounds were isolated from dried plant material by two methods: hydrodistillation and extraction with pentane used as control. Free volatile compounds as well as the aglycones obtained after enzymatic hydrolysis of gly-cosides were analyzed by gas chromatography-mass spectrometry (GC-MS). A significant difference in qualitative and quantitative composition of volatile compounds of the essential oil and pentane extract was found. The major components of the essential oil and pentane extract were linalyl acetate (21.46%; 42.02%), linalool (13.68%; 22.66%), 1,8-cineole (12.51%; 6.40%), β-myrcene (8.10%; 2.87%), α-terpineol (7.38%; 0.73%) and geranyl acetate (8.66%; 1.76%). The major components of the volatile aglycones were 1-octen-3-ol (40.28%), eugenol (12.29%), 3-octanol (7.09%), linalool (4.59%), benzyl alcohol (3.71%), 2-phenylethanol (3.67%), 3-hexene-1-ol (2.87%) and 1-heptene-3-ol (2.88%). Compared with free volatile compounds (essential oil: 1.56%; pentane extract: 1.64% ), the glycosidically bound volatiles were present in a lower concentration, about 0.0068%