Cossma 7-8/2013

C osmetic chemists have shown the importance of moisturisers for the topical treatment of dif- ferent skin types and ageing-related conditions. A vast array of personal care ingredients is on the market, but the moisturising properties of the polyhydroxy acid glucono-delta-lac- tone and its salts, the salts of lactic acid, as well as, the polyol erythritol, have not been explored in detail yet. This article describes the major con- stituents that make a good moisturis- ing product and to what extent those mentioned ingredients can contribute. Trend towards natural ingredients Consumers are increasingly attract- ed to using products that are made from naturally-derived or organic in- gredients. This trend towards more sustainability is served by Jungbun- zlauer providing a broad range of bio- based personal care ingredients with multifunctional properties. In different studies the moisturising benefits for leave-on as well as for rinse-off prod- ucts of ingredients such as sodium lactate, glucono-delta-lactone (GdL), sodium gluconate, potassium lactate, erythritol and calcium lactate glu- conate have been tested. Requirements for good moisturising products According to Kligman and Leyden, a good moisturizer can be defined as “a topically applied substance or prod- uct that overcomes the signs and symptoms of dry skin”. In order to strengthen the natural barrier function and keep the skin smooth and flexible, the following requirements need to be fulfilled: – maintain a water content of 20–35% – limited trans-epidermal water loss – preserved water homeostasis – sustained optimal lipid synthesis – allowance for orderly desquamation of stratum corneum (SC) cells An increase in transepidermal wa- ter loss (TEWL) to the extent that the water content of the SC is reduced to < 10% leads to clinical symptoms of a xerosis/xerodermia. Next to the func- tional aspects of skin moisturising there is also the goal to achieve a soft, supple, glowing, healthy looking skin, as subjectively evaluated by the end user. 18 COSSMA 7-8I2013 The mechanism of moisturisation Ingredients that contribute to effec- tive moisturising products can be clas- sified according to their functionality in three major groups: occlusives, humectants and emollients. There are more than 830 humec- tants listed in the CosIng database for cosmetic ingredients of the EU com- mission. Typical humectants are or- ganic water-soluble molecules that can attract and tightly bind a large number of water molecules, thus hydrate the skin. Glycerine is by far the most popu- lar of all humectants used in personal care products, but it features a sticky, unpleasant skin feel. Other naturally occurring moisturisers are amino acids, urea and lactates, being part of the natural moisturising factor (NMF) and supporting the function of a healthy skin. Moisturising performance The moisturising performance of GdL, of several lactate and gluconic acid salts and blends as well as erythri- tol has been evaluated in two-week in vivo studies using a Corneometer for Fig 1: Relative improvement of skin hydration after two weeks of application of a cream with and without 3% (w/w) moisturising ingredients High-perform- ance moisturizing leave-on and rinse-off products due to effective occlusives, humectants and emollients The choice for natural moisturising solutions with a proven performance for leave-on and rinse-off products is still limited. A team of experts from Jungbun- zlauer presents the results of new clinical studies for natural moisturising solutions designed for leave-on as well as rinse-off products based on lactates, gluconates, and polyols, and using glycerine as a positive control. photo:AfricaStudio,Shutterstock.com Improvementofskinmoisturecontent Control (A) Glycerine (B) Glucono-delta- Lactone (C) Sodium Lactate 60% aq. sol. (D) Sodium Gluconate/ Sodium Lactate (E) FOCUS: NATURAL COSMETICS INGREDIENTS Natural moisturising solutions COS1307-8_18_Jungbunz_GB_COS1307-8_14_Plantasense_D 26.07.13 11:28 Seite 18

Cossma 7-8/2013

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