IntroductionEssential oils are complex volatile natural compounds formed by aromatic plants as secondary metabolites. They are an important source of potential therapeutic compounds (Sherry et al., 2013). Essential oil constituents from aromatic herbs and dietary plants include monoterpenes, sesquiterpenes, oxygenated monoterpenes, oxygenated sesquiterpenes, and phenolics, among others (Bhalla et al., 2013).Sesquiterpenes, which are one of the most common terpenes, are a class of natural products with a diverse range of attractive industrial properties (Wang et al., 2011;Scalcinati et al., 2012). They are compounds containing 3 isoprene units, which have 15 carbons and 24 hydrogens per molecule (C 15 H 24 ). There are more than 10,000 kinds of sesquiterpenes (Davis and Croteau, 2000). They have long been investigated for biological activities including anticarcinogenic (