Cysteine is a semiessential proteinogenic amino acid with the formula HOOC−CH(−NH2)−CH2−SH. The thiol side chain in cysteine often participates in enzymatic reactions as a nucleophile. Cysteine is chiral, only L-cysteine is found in nature.
Cosmetics are constituted mixtures of chemical compounds derived from either natural sources, or synthetically created ones. Cosmetics have various purposes. Those designed for personal care and skin care can be used to cleanse or protect the body or skin. Cosmetics designed to enhance or alter one's appearance (makeup) can be used to conceal blemishes, enhance one's natural features, add color to a person's face, or change the appearance of the face entirely to resemble a different person, creature or object. Due to the harsh ingredients in makeup products, individuals with acne-prone skin are more likely to suffer from breakouts. Cosmetics can also be designed to add fragrance to the body.
Cosmetology is the study and application of beauty treatment. Branches of specialty include hairstyling, skin care, cosmetics, manicures/pedicures, non-permanent hair removal such as waxing and sugaring, and permanent hair removal processes such as electrology and intense pulsed light (IPL).
A humectant is a hygroscopic (water-absorbing) substance used to keep things moist. They are used in many products, including food, cosmetics, medicines and pesticides. When used as a food additive, a humectant has the effect of keeping moisture in the food. Humectants are sometimes used as a component of antistatic coatings for plastics.
Hair conditioner is a hair care cosmetic product used to improve the feel, texture, appearance and manageability of hair. Its main purpose is to reduce friction between strands of hair to allow smoother brushing or combing, which might otherwise cause damage to the scalp. Various other benefits are often advertised, such as hair repair, strengthening, or a reduction in split ends.
Shea butter is a fat extracted from the nut of the African shea tree. It is ivory in color when raw and commonly dyed yellow with borututu root or palm oil. It is widely used in cosmetics as a moisturizer, salve or lotion. Shea butter is edible and is used in food preparation in some African countries. Occasionally, shea butter is mixed with other oils as a substitute for cocoa butter, although the taste is noticeably different.
Mink oil is an oil used in medical and cosmetic products. It is obtained by the rendering of mink fat which has been removed from pelts destined for the fur industry.
Oleyl alcohol, or cis-9-octadecen-1-ol, is an unsaturated fatty alcohol with the molecular formula C18H36O or the condensed structural formula CH3(CH2)7−CH=CH−(CH2)8OH. It is a colorless oil, mainly used in cosmetics.
Hair spray is a common cosmetic hairstyling product that is sprayed onto hair to protect against humidity and wind and have it stay in a desired shape. Hair sprays typically consist of several components for the hair as well as a propellant.
Lead(II) acetate (also known as lead acetate, lead diacetate, plumbous acetate, sugar of lead, lead sugar, salt of Saturn, or Goulard's powder), is a white crystalline chemical compound with a slightly sweet taste. Its chemical formula is usually expressed as Pb(CH3COO)2 or Pb(OAc)2, where Ac represents the acetyl group. Like many other lead compounds, it is toxic. Lead acetate is soluble in water and glycerin. With water it forms the trihydrate, Pb(OAc)2·3H2O, a colourless or white efflorescent monoclinic crystalline substance.
Panthenol (also called pantothenol) is the alcohol analog of pantothenic acid (vitamin B5), and is thus a provitamin of B5. In organisms, it is quickly oxidized to pantothenic acid. It is a viscous transparent liquid at room temperature. Panthenol is used in pharmaceutical and cosmetic products as a moisturizer and to improve wound healing.
Alpha hydroxy acids, or α-hydroxy acids, are a class of chemical compounds that consist of a carboxylic acid with a hydroxyl group substituent on the adjacent (alpha) carbon. Prominent examples are glycolic acid, lactic acid, mandelic acid and citric acid.
Shampoo is a hair care product, typically in the form of a viscous liquid, that is used for cleaning hair. Less commonly, shampoo is available in solid bar format. Shampoo is used by applying it to wet hair, massaging the product into the scalp, and then rinsing it out. Some users may follow a shampooing with the use of hair conditioner.
Hair washing without commercial shampoo, sometimes called no poo includes water-only hair washing and hair washing with non-commercial products, such as baking soda and vinegar. Advocates argue that commercial shampoo is an unnecessary expense and may contain harmful ingredients.
Ammonium sulfite is the ammonium salt of sulfurous acid with the chemical formula (NH4)2SO3.
Sodium bisulfite (or sodium bisulphite, sodium hydrogen sulfite) is a chemical mixture with the approximate chemical formula NaHSO3. Sodium bisulfite in fact is not a real compound, but a mixture of salts that dissolve in water to give solutions composed of sodium and bisulfite ions. It appears in form of white or yellowish-white crystals with an odor of sulfur dioxide. Regardless of its ill-defined nature, sodium bisulfite is used in many different industries such as a food additive with E number E222 in the food industry, a reducing agent in the cosmetic industry, and a decomposer of residual hypochlorite used in the bleaching industry.
Egg oil, also known as egg yolk oil or ovum oil, is derived from the yolk of chicken eggs consisting mainly of triglycerides with traces of lecithin, cholesterol, biotin, xanthophylls lutein and zeaxanthin, and immunoglobulins. It is free of egg proteins and hence may be used safely by people who are allergic to eggs, for topical applications such as hair and skin care. The product has several historical references in Unani (Greek) medicine for hair care. Traditional Chinese medicine uses egg oil for burns, eczema, dermatitis, mouth ulcers, skin ulcers, chapped nipples, tinea capitis, ringworm, nasal vestibulitis, frostbite, and hemorrhoids.
Topilutamide, known more commonly as fluridil and sold under the brand name Eucapil, is an antiandrogen medication which is used in the treatment of pattern hair loss in men and women. It is used as a topical medication and is applied to the scalp. Topilutamide belongs to a class of molecules known as perfluoroacylamido-arylpropanamides.
Isophytol is a terpenoid alcohol that is used as a fragrance and as an intermediate in the production of vitamin E and K1.
Hair oil is an oil-based cosmetic product intended to improve the condition of hair. Various types of oils may be included in hair oil products. These often purport to aid with hair growth, dryness, or damage.
