Microemulsions for Sprayable Delivery and Other Topics: Literature Findings

By: Charles Fox, Independent Consultant

Posted: March 30, 2010, from the April 2010 issue of Cosmetics & Toiletries.

page 3 of 6

Among the selected organo-sulfur compounds, only PM displayed a significant inhibitory effect on tyrosinase activity. It also showed the highest inhibitory action on o-quinone formation. Further analysis of the inhibitory kinetics revealed that PM is a mixed-type inhibitor. This is the first study indicating that organo-sulfur compounds tested may play an important role in the regulation of melanin formation, making them potent candidates for skin lightening agents.

Silencing the siRNA gene to inhibit tyrosinase: Avon Products Inc. disclosed siRNA-mediated gene silencing oligomers to inhibit tyrosinase and reduce pigmentation.⁶ The described invention discusses compositions and methods for treating, preventing and improving hyperpigmentation or other unwanted pigmentation such as age spots and skin discoloration. The compositions preferably are applied to the skin or delivered by directed means to the site in need.

Fish DNA fragments for anti-wrinkle skin care: Jung has disclosed the preparation of DNA fragments from fish semen or egg by enzymic hydrolysis and their use in antiwrinkle skin care.⁷ The fish semen or egg must first be thawed, followed by hydrolyzing the DNA with enzymes at pH 7.0–7.4 under a temperature range of 43–47 °C; then sterilizing the DNA fragments under a temperature range of 100–109°C for 10–30 min in weak acidic solution and reducing the molecular weight of the fragments at pH 4.0–4.4 under a tempurature range of 68–72°C; and finally, precipitating and performing dry granulation. This method can be used to increase the efficacy of the preparation by 7% and the DNA fragments can be used in antiwrinkle skin care.

Hair and Hair Care
Indigofera tinctoria hair loss prevention: Shiseido Co., Ltd. discloses hair nourishment preparations containing an Indigofera tinctoria extract active solution to inhibit caspase 3.⁸ A hair loss preventive formula containing the caspase 3 inhibitor was also disclosed.

Emulsified hair styling composition: Shiseido Co., Ltd. also published a patent on an emulsified hair composition that exhibited excellent hair styling and hair moisturizing effects with no stickiness.⁹ The composition contained a polyhydric alcohol, a hydrophilic nonionic surfactant, an amphoteric surfactant and/or a semipolar surfactant, a higher fatty acid, and a high molecular weight silicone. An example of a hair styling composition is shown in Formula 1.