2.6.1.4 Enzymatic Hydrolysis
It has been observed that the volatile oil is normally found in plant substances in the form of odourless glycosidal combinations. However, the odoriferous components are liberated free only by hydrolysis of such aforesaid glycosides. A few typical examples of such volatile components are given below:2.6.1.4.1 Volatile Oil of Bitter Almond (Benzaldehyde) It is found to be present in the kernels of bitter almond in the form of the glyoside amygdalin:
2.6.1.4.2 Volatile Oil of Black Mustard The volatile oil component is present is allyl isothiocyanate in the form of the naturally occurring glycosides sinigrin:
2.6.1.4.3 Eugenol It occurs invariably in the form of glycosides combination as gein present in the roots of Geum urbanum Linn. belonging to family Rosaceae.
2.6.1.4.4 Methyl Salicyalate It is found to occur in the form of glycosidal combination as gaultherin (Synonym: monotropin or monotropitiside) in the leaves of Gaultheria procumbens Linn. belonging to family Ericaceae. The glycosides gaultherin undergoes hydrolysis in the presence of the enzyme gautherase to yield the aglycone methyl salicylate and the corresponding sugars glucose and xylose.
