Chemical composition of the essential oil of Ziziphora clinopodioides Lam. (Lamiaceae) from Georgia

Abstract

Taxa belonging to the Ziziphora L. genus are represented in the Caucasian flora [1,2] and are commonly used in traditional food and for medicinal purposes [2]. Ziziphora clinopodioides Lam. (Lamiaceae), known as blue mint bush is widespread in the Caucasus region and used to treat gastrointestinal disorders and as an aperitive, carminative, antiseptic and wound healing material [2]. To the best of our knowledge, there are limited data on the composition of Z. clinopodioides essential oil and no previous studies of the essential-oil constituents of Z. clinopodioides aerial parts from Georgia. The plant material used for the present study was collected near Jvari Monastery, Mtskheta, Georgia and subjected to hydrodistillation for 3 h using a Clevenger-type apparatus to produce the essential oil. The essential oil was analyzed by GC and GC-MS and this allowed the identification of 28 constituents representing 99% of the total detected GC-peak areas. The essential oil of Z. clinopodioides aerial parts from Georgia was found to be characterized by high levels of oxygenated monoterpenes, with the main components identified as pulegone (29.4%),
p-menth-3-en-8-ol (15.2%), germacrene D (9.2%), neomenthol (5.6%),
cis-pulegol (5.3%), menthofuran (4.5%), piperitenone (4.3%) and piperitone (3.1%). Pulegone, the most abundant constituent, is a widespread component of the Lamiaceae essential oils [3], however, it has been proven to be highly toxic to laboratory animals, primarily expressing pulmonary and hepatotoxic effects [4]. Having in mind that pulegone represents almost one-third of the oil, further toxicological studies of the Z. clinopodioides aerial parts essential oil are needed.