The Essential Oil Components in Lemon Verbena Significantly Vary According to Diurnal Variations and Drying Process

This study investigated the effects of harvesting time, dried, and or fresh leaf on essential oil components in lemon verbena (Lippia citriodora H.B.K.). Essential oil was obtained from fresh and dried leaves harvested at different times using the hydro-distillation method. The essential oil components were determined using a GC-MS device. A two-way analysis of variance (ANOVA) was applied to the essential oil components determined at all harvesting times (HT), on dry or fresh (DF) leaves. Except for Myrcene and Guaiol, the essential oil content of Limonene, ß-Citral, α-Citral, Caryophyllene oxide, ß-Guaiene, Geranyl acetate, Prenylacetone, Linalool, Verbenol, Humulene, Curcumene, Carvone, Nerolidol, Spathulenol, and α-Cadinol were significantly affected by the HT×DF interactions (P<0.05). It was found that especially for the cosmetic industry, Limonene should be obtained from fresh leaves harvested at 12(pm), β-Citral from fresh leaves harvested at 12(am), and α-Citral from dry leaves harvested at 6(pm), which are active compounds derived from the volatile oil of lemon verbena. According to the PCA results obtained from the study, we can clearly state that harvesting time has differently influenced each active compound in the essential oil of lemon verbena. This study has provided important insights into the application areas of the active compounds derived from the essential oil of lemon verbena.