Eucalyptus: phytochemical composition, extraction methods and food and medicinal applications

Eucalyptus is a large tree belonging to the family Myrtaceae. It is a tree of multiple uses and benefits. The essential oil extracted from its leaves, branch tips and fruits is rich in phytochemicals like eucalyptol, 1,8-cineole, limonene, citronellal, citral, eudesmol, α and β-pinene, p-cymene, terpinen-4-ol, terpineol, α–phellanderene and 9β-sitosterol etc. These compounds can be extracted by various methods like solvent extraction method, hydro-distillation and supercritical fluid extraction. The essential oil from the eucalyptus possesses anti-bacterial, anti-viral, anti-fungal, antioxidant, antimalarial, analgesic, antiseptic, anti-diabetic, anti-cancerous, anti-inflammatory and cytotoxic properties. The historical records of the food and medicinal applications of eucalyptus are available and the recent studies on its phytochemical composition further strengthen its claim for application in the modern food and pharmaceutical industry.