Eucalyptus Oil : Method of Preparation, Chemical Constituents and Uses

Source and Distribution of Eucalyptus Oil:

Eucalyptus oil is the volatile oil which is obtained by distillation from the fresh leaves of Eucalyptus globulus and the other species of Eucalyptus, which belongs to the family Myrtaceae.

It is also known as Eucalyptus, dinkum oil and lemon gum tree. It is cultivated in Australia, Tasmania, United States, California, Spain, Portugal, India. Large scale production of Eucalyptus citriodora which is also known as citron scented or lemon scented gum is grown in Kerala, Tamil Nadu and other states.

Preparation of Eucalyptus Oil:

English: Glass vial containing Eucalyptus Globulus Essential Oil (Photo credit: Wikipedia)

The Eucalyptus oil is commercially prepared in Niligiris on large scale. The trees which are of 16 years of age are preferred for the collection of leaves. The leaves which weigh about 750 to 1200kg are collected per hectare. The leaves are dried in shade for about 3 days and then they are subjected to steam distillation. The distillation unit consists of a false perforated bottom made of copper. At a single charge, it contains 350 kg of leaves. Sufficient amount of water is also charged into the still and the steam under pressure is passed through it. The distillation takes about 6 hours for completion. Eucalyptus oil is produced and is collected in the receiver. Crude oil is produced and it is rectified again after treating it with sodium hydroxide. The oil is filtered and is filled in suitable containers. The oil is colourless or pale yellow coloured liquid, with aromatic and camphoraceous odour and pungent taste. It gives cold sensation after tasting.

Chemical constituents of Eucalyptus Oil :

It mainly contains cineole which is also known as eucalyptol. The other components are pinene, camphene, phellandrene, citronellal and geranyl acetate.

Uses of Eucalyptus Oil:

• Counter irritant
• Antiseptic
• Expectorant
• Relieves cough
• Used in chronic bronchitis
• Used as inhalation
• Ingredient for several liniments and ointments
• Eucalyptus oil solution is used as nasal drops

English: Eucalyptus globulus (fruit). Location: Maui, Makawao Forest Reserve (Photo credit: Wikipedia)

It is stored in well closed container away from light and in cool place.