Corymbia citriodora: A Valuable Resource from Australian Flora for the Production of Fragrances, Repellents, and Bioactive Compounds

Abstract

As global chemical manufacturing has historically relied on inexpensive feedstocks from the petrochemical industry, the identification of new naturally derived feedstocks represents an important and sustainable alternative. This review introduces Corymbia citriodora (Hook.) K.D.Hill & L.A.S.Johnson as an attractive renewable resource of natural compounds for organic chemical transformations. Although native to Australia, this plant species is now grown and harvested worldwide. The chemical composition of citriodora oils varies with location, harvesting season and age of leaves. Beyond their historic uses as fragrances or repellents, the more abundant terpenes found in citriodora oils such as citronellal, citronellol, and isopulegol have notable roles in the manufacture of fine chemicals. This review highlights several industrial processes intimately related to the citriodora terpenes, some advances in fragrances and repellents, as well as the use of these terpenes in the most recently reported synthesis of bioactive compounds. Where relevant, processes highlighting the adoption of green chemistry principles are presented and briefly discussed.

Solar Photooxygenations for the Manufacturing of Fine Chemicals—Technologies and Applications

“…Many of the industrially relevant photochemical processes convert naturally occurring or semi-synthetic starting materials to their corresponding oxygenated products [ 53 , 54 , 55 ]. Of these, essential oil derived starting materials are especially common [ 55 , 77 ], which makes photooxygenations promising applications for product diversification and value-adding in the essential oil industry [ 78 ]. This review will focus on demonstration (multigram)- to technical (multikilogram)-scale transformations conducted in purpose-designed solar reactors.…”

Insecticidal and Repellent Activities of Four Essential Oils Against Sitophilus zeamais (Coleoptera: Curculionidae)

“…Johnson (Myrtaceae) essential oil include allelopathic (bioherbicide), antimicrobial, insect toxicity, and repellent effects, especially against S. zeamais and mosquitoes (Diptera: Culicidae) and perfumery. [21][22][23] The tea tree, Melaleuca alternifolia (Maiden and Betche) Chee (Myrtaceae) essential oil when topically applied presents anti-microbial properties and has insecticidal action, especially against S. zeamais. 24,25 The essential oil of peppermint, Mentha × piperita L. (Lamiaceae) is used for culinary, medicinal products, and agricultural, and domestic insecticides, 26,27 while that of the Brazilian peppertree, Schinus terebinthifolius Raddi (Anacardiaceae) presents astringent, antibacterial, antiviral, diuretic, digestive stimulant, tonic, and wound healing properties.…”