Enzyme-Catalysed Conversion of Atranol and Derivatives into Dimeric Hydrosoluble Materials: Application to the Preparation of a Low-Atranol Oakmoss Absolute

Oakmoss absolute, a solvent extract from Evernia prunastri, is a valuable fragrance ingredient widely used in fine fragrance for almost two centuries. Some minor components of oakmoss absolute, such as atranol and chloroatranol, are attested contact allergens and their presence in fragrance and cosmetic products should be as low as possible. In this context, we have developed an enzyme-based protocol upon which these undesirable molecules are converted in a hydrosoluble dimeric material, and thus easily separated from the absolute by liquid⁻liquid extraction. Analytical and sensory analyses were performed to confirm the specificity of the process, the absence of alteration of the olfactory quality of the absolute, and the final titles of atranol and chloroatranol, which eventually were observed in the ppm range. This highly sustainable process is a viable alternative to conventional time-, energy-, and manpower-consuming techniques to produce very low-atranol oakmoss absolute.