Hippocratic medicinal flora on the Greek Island of Kos: Spatial distribution, assessment of soil conditions, essential oil content and chemotype analysis

Abstract

In recent years, interest in traditional medicine has significantly increased worldwide. Our research focused on an extended survey conducted in Kos Island in order to determine the distribution of Hippocratic Medicinal Flora, to evaluate the composition of their essential oils and the relationship between their occurrence and the soil environment. Cistus salviifolius, Hypericum empetrifolium and Teucrium capitatum were mostly observed at higher altitudes, whereas Hypericum hircinum, Crithmum maritimum, Anthemis arvensis, Ferula communis and Artemisia arborescens at lower ones. Canonical correspondence analysis served to quantify the relationship among soil variables and the occurrence and density of the studied plant species. The most important variables according to CCA were in decreasing order Na, soil organic content (%) and pH. Three species exhibited high essential oil yields, namely A. arborescens (3.4%), H. empetrifolium (3%) and C. maritimum (2.3%). Germacrene D was the main constituent of the essential oil of C. salviifolius and T. capitatum, while (cis)-chrysanthenyl acetate was for A. arvensis. For C. maritimum, the main constituent was sabinene, E-caryophyllene for H. hircinum, α-pinene for H. empetrifolium, δ-cadinene for F. communis, and chamazulene for A. arborescens. The domestication feasibility of the aforementioned plant species is also discussed.