Walking through a rose garden is pleasant and joyful due to our sensitive noses sensing the essential oil components such as monoterpenes emitted from roses. There are an astonishing number of volatile organic compounds, primarily monoterpenes in the air, emitted from plants. Monoterpenes are the fragrant components of the essential oils. Essential oils have been used for a wide range of applications such as cooking spices, aromatherapy, perfumery, medicinal therapies, pesticides and food preservatives. Citronella oil obtained from the plants Cymbopogon (lemongrass) is used topically on people to control mosquitoes and other pests of medical importance. Basil (Ocimum basilicum) is a popular culinary herb. Basil oil has shown to be a potent biopesticide and food preservative. Basil oil contains more than 200 chemicals. Carvacrol, linalool and pulegone in basil oil showed excellent potency against thrips, melon fly, as well as turnip aphids. Basil oil, and its major components trans-anethole, estragole, and linalool are very potent against adult fruit flies of Ceratitis capitata, Bactrocera dorsalis, and Bactrocera cucurbitae. Electrophysiological studies indicated that linalool inhibits both mammalian γ-aminobutyric acid type A receptor (GABA_AR) and nicotinic acetylcholine receptor (nAChR), which may explain its insecticidal activity. Linalool is a concentration-dependent, non-competitive inhibitor on the GABA_AR. The half maximal inhibitory concentration (IC₅₀) of linalool on the GABA_AR and nAChR was approximately 3.2 mM and 3.0 mM, respectively. In this talk, we will also have a summary with new perspectives of the book recently published “Pesticides Organic Contaminants and Pathogens in Air: Chemodynamics, Health Effects and Analysis.” This book describes the use of terpenes among the many natural products as biopesticides and now accepted for organic food production. The monoterpene camphene is chlorinated to produce toxaphene. Toxaphene contains over 700 individual congeners, only a few of which are potent insecticides. There are sure to be terpenes and terpene blends yet to be developed that can play roles in pest control in the future.

James Seiber

Appearances