Extraction of bioactive cosmetic compounds

In the cosmetics industry, every manufacturing process involves, directly or indirectly, extraction. Cosmetic active ingredients extracted from medicinal plants, aromatic herbs and spices are the result of a complex mixture of chemical substances. What's more, they are generally present in very low concentrations in the plants themselves. Before such substances can be used in cosmetic formulations, they need to be extracted from their plant matrix. Several extraction methods have been developed, including petrochemical solvent extraction, steam stripping, hydrodiffusion and maceration. However, these compounds are known to be thermosensitive and vulnerable to chemical reactions. The loss of certain constituents, the degradation of certain unsaturated compounds by thermal effect or hydrolysis, as well as the presence of more or less toxic organic solvent residues can be generated by these extraction techniques. These drawbacks have attracted the attention of a number of academic and industrial research laboratories, leading to the development of new, much more environmentally-friendly extraction techniques for cosmetic active ingredients, using less toxic solvents and in smaller quantities, such as :

• supercritical fluid extraction ;

• subcritical water extraction ;

• the use of agro-solvents ;

• flash détente ;

• controlled instantaneous expansion ;

• turbodistillation ;

• extrusion ;

• ultrasound ;

• microwave extraction.

The main challenges facing chemists are to control or accelerate chemical reactions by means of mechanical, thermal or electromagnetic energy flow. The simple act of heating or mixing a reaction medium is one such means of control. Technological advances have given rise to even more specific applications that are now used in our everyday lives. This article presents scientific advances in the field of cosmetic active ingredient extraction, in terms of both intensification and sustainability, in order to achieve optimum extract quality, raw material consumption and energy efficiency.

This article presents :

• the overall process for obtaining cosmetic active ingredients, detailing each unit operation and showing the methodological and technological variants;

• the concept, technology and application of new, innovative or intensified extraction techniques;

• the substitution of petroleum solvents by alternative solvents, from both...