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Orange Roughy Oil for Sensitive Skin and Other Topics: Literature Findings
By: Charles Fox, Independent Consultant
Posted: March 31, 2009, from the April 2009 issue of Cosmetics & Toiletries.
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Thus, molecular targets for skin pigmentation associated with aging should be focused on mechanisms related to the EMU. There are three basic approaches. The first is the melanin/melanosome exfoliation process, which can be subdivided into exfoliation of horny-layered cells, accelerated growth of these cells, and their water and sebum content. The second is the transfer and degradation of melanin/melanosomes, which concerns molecules affecting the growth and differentiation of either melanocytes, keratinocytes or both. The third target are the molecules responsible for melanin and melanosome biosynthesis.
The step-by-step dissection of each of these processes should provide improved or novel management of aging-related facultative skin pigmentation.
Photostable UV absorber: Shiseido Company Ltd. has disclosed sunscreens including dibenzoylmethane derivatives in combination with alkyl diphenylacrylate and benzalmalonate derivatives10 that do not hinder the photostabilizing effect of the dibenzoylmethane derivatives. The composition is an effective UV absorber across a wide wavelength range, from UVA to UVB. Specifically, the composition contains a dibenzoylmethane derivative; an alkyl beta, beta-diphenylacrylate and/or an alpha-cyano-beta, beta-diphenylacrylate (for example, octocrylene); and a specific benzalmalonate derivative; for example, di-(2-ethylhexyl)-4-methoxybenzalmalonate.
Broad-spectrum UV filter: Herzog et al. review the development of broad-spectrum UV filters for cosmetic applications.11 Modern sunscreens must protect against both UVB and UVA radiation. This requires UVB absorbers as well as photostable UVA or broad-spectrum UV filters. Bis-ethylhexyloxyphenol methoxyphenyltriazine (BEMT)a is a hydroxy-phenyl-triazine derivative that is designed for optimal spectral performance and solubility in cosmetic oils. Due to its molecular structure, the material exhibits a UV spectrum with two absorption peaks, indicating broad-spectrum protection even at the low concentration of 2%. It also exhibits efficacious photostability based on rapid photo-tautomerization, recognized by a change in molecular configuration brought about with exposure to UV.
The material can efficiently stabilize photo-labile UV filters such as T-butylmethoxydibenzoylmethane or ethylhexyl methoxycinnamate. Furthermore, it shows a synergistic effect on SPF with commonly used UVB filters as well as with bis-benzotriazolyl tetramethylbutylphenol.b