Keratin hydrolysates (KHs) are established standard components in hair cosmetics. Understanding the moisturizing effects of KH is advantageous for skin-care cosmetics. The goals of the protocol are: (1) to process chicken feathers into KH by alkaline-enzymatic hydrolysis and purify it by dialysis, and (2) to test if adding KH into an ointment base (OB) increases hydration of the skin and improves skin barrier function by diminishing transepidermal water loss (TEWL). During alkaline-enzymatic hydrolysis feathers are first incubated at a higher temperature in an alkaline environment and then, under mild conditions, hydrolyzed with proteolytic enzyme. The solution of KH is dialyzed, vacuum dried, and milled to a fine powder. Cosmetic formulations comprising from oil in water emulsion (O/W) containing 2, 4, and 6 weight% of KH (based on the weight of the OB) are prepared. Testing the moisturizing properties of KH is carried out on 10 men and 10 women at time intervals of 1, 2, 3, 4, 24, and 48 h. Tested formulations are spread at degreased volar forearm sites. The skin hydration of stratum corneum (SC) is assessed by measuring capacitance of the skin, which is one of the most world-wide used and simple methods. TEWL is based on measuring the quantity of water transported per a defined area and period of time from the skin. Both methods are fully non-invasive. KH makes for an excellent occlusive; depending on the addition of KH into OB, it brings about a 30% reduction in TEWL after application. KH also functions as a humectant, as it binds water from the lower layers of the epidermis to the SC; at the optimum KH addition in the OB, up to 19% rise in hydration in men and 22% rise in women occurs.

Department of Fat Tenside and Cosmetics Technology Faculty of Technology Tomas Bata University in Zlín

Department of Polymer Engineering Faculty of Technology Tomas Bata University in Zlín

Department of Polymer Engineering Faculty of Technology Tomas Bata University in Zlín;

Zobrazit více v PubMed

United States Department of Agriculture - National Agricultural Statistics Services. Poultry Slaughter, 2016 Summary. 2016. Feb,

McGovern V. Recycling poultry feathers: more bang for the cluck. Environ.Health Perspect. 2000;108(8):A336–A339. PubMed PMC

Gousterova A, et al. Degradation of keratin and collagen containing wastes by newly isolated thermoactinomycetes or by alkaline hydrolysis. Lett. Appl. Microbiol. 2005;40(5):335–340. PubMed

Yamauchi K, Yamauchi A, Kusunoki T, Khoda A, Konishi Y. Preparation of stable aqueous solution of keratins, and physiochemical and biodegradational properties of films. Biomed. Mater. Res. 1996;31(4):439–444. PubMed

Schrooyen PMM, Dijkstra PJ, Oberthur RC, Bantjes A, Feijen J. Partially carboxymethylated feather keratins. 2. Thermal and mechanical properties of films. J. Agric. Food Chem. 2001;49(1):221–230. PubMed

Mark HF, Gaylord NG, Bikales NM. Encyclopedia of Polymer Science Technology: vol. 8: Keratin to Modacrylic Fibers. New York: Wiley-Interscience; 1968.

Bertsch A, Cello N. A biotechnological process for treatment and recycling poultry feathers as a feed ingredient. Bioresour. Technol. 2005;96(15):1703–1708. PubMed

Grazziotin A, Pimentel FA, de Jong EV, Brandelli A. Nutritional improvement of feather protein by treatment with microbial keratinase. Animal Feed Sci. Technol. 2006;126(1-2):135–144.

Brandelli A. Bacterial keratinases: useful enzymes for bioprocessing agroindustrial wastes and beyond. Food Bioprocess Technol. 2008;1(2):105–116.

Gusta R, Ramnani P. Microbial keratinases and their prospective applications: an overview. Appl.Microbiol. Biotechnol. 2006;70(1):21–33. PubMed

Vasileva-Tonkova E, Gousterova A, Neshev G. Ecologically safe method for improved feather wastes biodegradation. International Biodeterior & Biodegradation. 2009;63(8):1008–1012.

Lodén M. Hydrating Substance. In: Barel AO, Paye M, Maibach HI, editors. Handbook of Cosmetic Science and Technology. New York: Informa, Healthcare; 2009. pp. 107–119.

Teglia A, Secchi G. Chapter 9: Proteins in Cosmetics. In: Goddard ED, Gruber JV, editors. Principles of Polymer Science and Technology in Cosmetics and Personal Care. New York: Marcel Dekker; 1999.

Magdassi S. Delivery systems in cosmetics. Colloids and Surfaces A: Physicochem. Engin. Aspects. 1997;123-124:671–679.

Dahms G, Jung A, inventors. Method for producing a protein hydrolysate. 20140323702. U.S. Patent. 2014

Pons R, Carrera I, Erra P, Kunieda G, Solans C. Novel preparation methods for highly concentrated water-in-oil emulsions. Colloids and Surfaces A: Physicochem. Engin. Aspects. 1994;91(3):259–266.

Mokrejs P, Hrncirik J, Janacova D, Svoboda P. Processing of keratin waste of meat industry. Asian J. Chem. 2012;24(4):1489–1494.

Mokrejs P, Svoboda P, Hrncirik J. Processing poultry feathers into keratin hydrolysate through alkaline-enzymatic hydrolysis. Waste Manage. Res. 2011;29(3):260–267. PubMed

Mokrejs P, Krejci O, Svoboda P. Producing keratin hydrolysates from sheep wool. Orient. J. Chem. 2011;27(4):1303–1309.

Mokrejs P, Krejci O, Svoboda P, Vasek V. Modeling technological conditions for breakdown of waste sheep wool. Rasayan J. Chem. 2011;4(4):728–735.

Polaskova J, Pavlackova J, Vltavska P, Mokrejs P, Janis R. Moisturizing effect of topical cosmetic products applied to dry skin. J. Cosmet. Sci. 2013;64(5):329–340. PubMed

Polaskova J, Pavlackova J, Egner P. Effect of vehicle on the performance of active moisturizing substances. Skin Res. Technol. 2015;21(4):403–412. PubMed

Verdier-Sévrain S, Bonté F. Skin hydration: a review on its molecular mechanisms. J. Cosmet. Dermatol. 2007;6(2):75–82. PubMed

Darlenski R, Sassning S, Tsankov N, Fluhr JW. Non-invasive in vivo methods for investigation of the skin barrier physical properties. Eur. J. Pharm. Biopharm. 2009;72(2):295–303. PubMed

Berardesca E. EEMCO guidance for assessment of stratum corneum hydration: electrical methods. Skin Res. Technol. 1997;3(2):126–132. PubMed

Rogiers V. EEMCO guidance for the assessment of transepidermal water loss in cosmetic sciences. Skin Pharmacol. Appl. Skin Physiol. 2001;14(2):117–128. PubMed

Ali SM, Yosipovitch G. Skin pH: from basic science to basic skin care. Acta Derm. Venereol. 2013;93(3):261–267. PubMed

Agache P, Humbert P. Measuring the Skin. Berlin: Springer-Verlag; 2004.

Council for International Organizations of Medical Sciences. International Ethical Guidelines for Biomedical Research Involving Human Subjects. Geneva: 2002. PubMed

Ruland JK. Transdermal permeability and skin accumulation of amino acids. Int. J. Pharm. 1991;72(2):149–155.

Draelos ZD. Therapeutic moisturizers. Dermatol. Clin. 2000;18(4):597–607. PubMed

Courage and Khazaka Electronic GmbH, Technical Charges. Information and Operating Instructions for the Multi probe Adapter MPA and its Probe. 2013.