Oligopeptides in Sensory, Proteins in Winter Skin and Carotenoids: Literature Findings

By: Charles Fox, Independent Consultant

Posted: November 26, 2008, from the December 2008 issue of Cosmetics & Toiletries.

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Hair and Hair Care
Raw materials for hair repair: Ikeda et al. review the properties of functional raw materials for hair care.⁸ In the described study, the authors evaluated three raw materials for their ability to rapidly repair damaged hair. A polymer blenda of butyl acrylate/isopropyl acrylamide/PEG-18 dimethacrylate crosspolymer was composed of thermo-responsive, highly-polymerized compounds and hydrophilic, highly-polymerized compounds.

The aqueous solution of this polymer becomes a hydro-gel that forms a sol-gel change at high temperatures. At a transition point, the thermo-responsive, highly-polymerized compound becomes a hydrophobic molecule and produces a hydrophobic film at low concentrations. Researchers found that this hydrophobic film controlled hair moisture content.

Also, liquefied shea was confirmed to absorb UV rays and can be used in hair care formulations to protect hair. Finally, hematinb was combined with the side chain of cysteine and histidine on the surface of the hair and found to repair damaged hair. It additionally was found to assist in maintaining permanent waves by holding moisture in hair.

Mild oxidation coloring: Doering et al. have published on super mild oxidation coloring and preventing hair damage at the molecular level.⁹ Hydrogen peroxide is widely used for oxidation hair coloring or bleaching. It displays a high redox potential and easily penetrates into the hair fiber. This renders hydrogen peroxide capable of nonspecific interactions with cortex and cuticle proteins, resulting in irreversible cleavage of cystine cross-links.

In the present work, various classes of antioxidants were screened for anti-damage effects in a permanent hair dye formulation using NIR spectroscopy. In parallel, the effect of coloring and lightening performance was studied to exclude unwanted side effects on primary product performance. The screening criteria were fulfilled by organic disulfides such as alpha-lipoic acid but interestingly not by antioxidants such as tocopherol, dibutylhydroxytoluene or beta-carotene.