Cymbopogon, better known as lemongrass, is a genus of Asian, African, Australian, and tropical island plants in the grass family. Some species (particularly Cymbopogon citratus) are commonly cultivated as culinary and medicinal herbs because of their scent, resembling that of lemons (Citrus limon). Common names include lemon grass, barbed wire grass, silky heads, citronella grass, cha de Dartigalongue, fever grass, tanglad, hierba Luisa, or gavati chahapati, amongst many others.
The essential oil of the lemon-scented gum mainly consists of citronellal (80%),[4] produced largely in Brazil and China.[5] Unrefined oil from the lemon eucalyptus tree is used in perfumery, and a refined form of this oil is used in insect repellents, especially against mosquitoes. The refined oil’s citronellal content is turned into cis- and trans- isomers of p-menthane-3,8-diol (PMD), a process which occurs naturally as the eucalyptus leaves age. This refined oil, which includes related compounds from the essential corymbia citriodora, is known widely by its registered tradename, “Citriodiol”, but also by generic names which vary by region: “oil of lemon eucalyptus” or “OLE” (USA); “PMD rich botanic oil” or “PMDRBO” (Europe); “PMD and related oil of lemon eucalyptus compounds” (Canada); Extract of Lemon Eucalyptus (Australia). Pure PMD is synthesized for commercial production from synthetic citronellal.