Proteins, in cosmetics

Advances in skin care and aesthetic science promoted the inclusion of many polypeptides and proteins in cosmetic formulation for their superior skin conditioning properties. Some widely used polypeptides and proteins are described below. 

Because of their poor water solubility (the main technical requisite for the use of proteins in cosmetic formulations) and the difficulty of extraction from the matrix, most proteins are unsuitable for use in the manufacture of cosmetic preparations in the form in which they occur in nature. Only a few native proteins, such as collagen, serum albumin, and enzymes, can be isolated as soluble native proteins. To make proteins suitable for use in water-based cosmetic products and in a wide range of applications, natural proteins need to be converted into a soluble form this is usually attained by the hydrolysis procedure, i.e., cleavage of the protein macromolecule by disruption of some of the peptide bonds. 

IV. ROLE AND FUNCTIONS OF PROTEINS IN COSMETICS A. General Aspects... 

Johnsen VF. Proteins in cosmetics and toiletries. Drug Cosmet Ind 1980 126 36-39. Morganti P, Muscardin F, Fabrizi G. Protective effect of collagen upon irritation response of detergents. Int J Cosmet Sci 1983 5 7-14. 

In Cosmetics. Amino acids and their derivatives occur in skin protein, and they exhibit a controlling or buffering effect of pH variation in skin and a bactericidal effect (216). Serine is one component of skin care cream or lotion. Ai-Acylglutamic acid triethanolamine monosalt is used for shampoo. Glucose glutamate is a moisturizing compound for hair and skin (234). 

Uses. As broad-spectrum antimicrobial cold sterilant/disinfectant for hospital equipment as tanning agent for leather as tissue fixative as cross-linking agent for proteins as preservative in cosmetics as therapeutic agent for warts, hyperhidrosis, and dermal mycotic infections in X ray processing solutions and film emulsion as a disinfectant in the beauty industry... 

The Alkylglycosides (AGs) and Sucrose esters of fatty acids (SEFAs) are families of nonionic glycosurfactants that have been used for their ability to gently extract membrane proteins with a minimal loss of functionality. These compounds can be synthesized and purified economically, with a worldwide production of thousands of tons per year. Chemically, AGs and SEFAs are a group of uncharged amphipathic compounds that consist of an aliphatic hydrocarbon chain attached to a sugar moiety. Certain AGs and SEFAs such as dodecanoyl sucrose have enjoyed widespread use as food-grade emulsifiers and in cosmetic preparations. 

Another class of surfactants that are used in cosmetics and personal care products is the phosphoric acid esters. These molecules are similar to the phospholipids that are the building blocks of the stratum corneum (the top layer of the skin, which is the main barrier for water loss). Glycerine esters, in particular, triglycerides, are also frequently used. Macromolecular surfactants of the A-B-A block type [where A is PEO and B is polypropylene oxide (PPO)] are also frequently used in cosmetics. Another important naturally occurring class of polymeric surfactants is the proteins, which can be used effectively as emulsifiers. 

Sanchez-Perez, J., Sanz, T., and Garcfa-Dlez, A., Allergic contact dermatitis from hydrolyzed wheat protein in a cosmetic cream, Contact Dermatitis, 42, 360, 2000. 

Protein-rich rape seed residues from biodiesel production plants are rich in phenolic compounds, glucocinolates and phytic acid. Phenolic compounds and phytic acid could be used as potent antioxidants in cosmetic and pharmaceutical formulations (Shamsuddin, 1995 Amarowicz and Shahidi, 1994 Wanasundara et al., 1996 Oatway et al., 2001). Derivatives from glucosinolate hydrolysis, including isothiocyanates, thiocyanates and nitriles, could be used as anticarcinogenic agents, biopesticides and flavour compounds (Halkier and Gershenzon, 2006). 

Another threat which comes with natural products is microbes. The ingredients in cosmetics, such as water, oils, carbohydrates, minerals, and proteins, make them an ideal medium in which bacteria can multiply, as some purchasers of purely natural beauty products have discovered to their cost, not least of which is the disagreeable odour they emit which indicates they are going off. Even such natural products must now contain anti-bacterial agents and these must be proven to work, which is why they are generally synthetic chemicals. The ones most used and most effective at... 

The first plant product commercially produced by plant cell culture was the prenylated anthraquinone shikonin 16, from the boraginaceous plant Lithospermum erythrorhizon Sieb. et Zucc. (Mitsui Petrochemical Industry Company) in 1983.25 Shikonin is used as a dye in cosmetics (lipsticks, soaps and lotions) and its production yield from cell cultures was over ten-fold its isolation yield from the intact plant.25 In practice, eight runs of two weeks each in a 200 L bioreactor could afford the amount of shikonin produced in four years by a 1 ha field of L. erythrorhizon 25 Shikonin has an interesting and pleiotropic biological profile, which includes insulin mimicry and interference with protein-protein interactions, but it has not yet found medicinal application.26... 

O Donovan, C. J. (1976). Recent studies of lysinoalanine in alkali-treated proteins. Fd. Cosmet. Toxicol 14, 483-489. 

Oils used in cosmetics are usually light in color or are colorless therefore, it is necessary to conduct a bleaching step with adsorbents to remove colored materials as well as other impurities such as peroxides, metals, soaps, and protein residues. Once the oil has been properly refined and adsorbent-treated, it can be deodorized by sparging pure steam under high-vacuum. Physical refining or nonchemical removal of free fatty acids and odors by high vacuum distillation can also be accomplished however, care should be exercised to ensure that contaminants such as metals, soap, and proteins are effectively removed prior to the distillation step. 

The aluminum hydroxide gel referred to in the USP 28 is used in cosmetics as an emollient, filler, humectant, a mild astringent, and viscosity controlling agent. In pharmaceutical preparations it is used as an adsorbent, and as a protein binder. It is also used therapeutically as an antacid, and as an abrasive in dentrifrices. It is not, however, used as a vaccine adjuvant. 

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