Cinnamaldehyde, cinnamyl alcohol, cinnamic acid and their derivatives as cosmetics ingredients
Agnieszka Gunia, Henryk Marona
Pracownia Chemii Kosmetycznej, Zakład Chemii Bioorganicznej, Katedra Chemii Organicznej, Wydział Farmaceutyczny, Uniwersytet Jagielloński Collegium Medicum w Krakowie
Cinnamaldehyde, cinnamyl alcohol and cinnamic acid constitute widespread components of plants, where they play various roles. They are also used as cosmetic materials. The development of science and technology enabled to use not only natural products but also synthesis of new compounds in scientific laboratories and moreover, obtaining several derivatives which are characterized by particular properties as a result of changes in the structure. Compounds form that group are used mostly as perfuming agents but some of them are also used as other different ingredients like masking, skin/hair conditioning, antioxidant, or antimicrobial. Due to presence of conjugated double bonds they are able to absorb some ranges of ultraviolet radiation. That property enabled to use derivatives of cinnamic acid in cosmetic products as UV absorbers and UV filters, to protect both cosmetics as well as consumers´ skin and hair from adverse effects of UV radiation. p-Methoxycinnamic acid esters with 2-ethylhexan-1-ol (OMC) and isoamyl alcohol (isoamyl p-methoxycinnamate) as well as 2-cyano-3,3-diphenylprop-2-enoic acid ester with isoamyl alcohol (octocrylene) are well known UVB filters. Occurrence of compounds from that group has become so common that caused conducting of research evaluating their effectiveness but most of all their safety. Some reports which proved possibility of occurrence of allergic reactions caused by perfuming agents have been published. Moreover, one of the UV filter, octocrylene, has been identified as emerging photoallergen. Few compounds from that group are included in the list of substances which cosmetic products must not contain except subject to some restrictions. In that case restrictions mostly concern maximum concentration in ready for use preparation.
Cinnamaldehyde, cinnamyl alcohol and cinnamic acid derivatives are important cosmetic ingredients which should be interested for people associated with cosmetology.
Key words: cinnamaldehyde, cinnamyl alcohol, cinnamic acid, perfuming, UV filters, contact allergy, photoallergic contact dermatitis