Allantoin is a chemical compound with formula C
4H
6N
4O
3. It is also called 5-ureidohydantoin or glyoxyldiureide. It is a diureide of
glyoxylic acidGlyoxylic acid or oxoacetic acid is an organic compound. Together with acetic acid, glycolic acid, and oxalic acid, glyoxylic acid is one of the C2 carboxylic acids. It is a colourless solid that occurs naturally and is useful industrially....
.
Named after the
allantoisAllantois is a part of a developing animal conceptus . It helps the embryo exchange gases and handle liquid waste....
, an
amnioteThe amniotes are a group of tetrapods that have a terrestrially adapted egg. They include synapsids and sauropsids , as well as their fossil ancestors. Amniote embryos, whether laid as eggs or carried by the female, are protected and aided by several extensive membranes...
embryonic excretory organ in which it concentrates during development in most
mammalMammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
s except humans and higher apes, it is a product of oxidation of
uric acidUric acid is a heterocyclic compound of carbon, nitrogen, oxygen, and hydrogen with the formula C5H4N4O3. It forms ions and salts known as urates and acid urates such as ammonium acid urate. Uric acid is created when the body breaks down purine nucleotides. High blood concentrations of uric acid...
by
purineA purine is a heterocyclic aromatic organic compound, consisting of a pyrimidine ring fused to an imidazole ring. Purines, including substituted purines and their tautomers, are the most widely distributed kind of nitrogen-containing heterocycle in nature....
catabolismCatabolism is the set of metabolic pathways that break down molecules into smaller units and release energy. In catabolism, large molecules such as polysaccharides, lipids, nucleic acids and proteins are broken down into smaller units such as monosaccharides, fatty acids, nucleotides, and amino...
. After birth, it is the predominant means by which nitrogenous waste is excreted in the
urineUrine is a typically sterile liquid by-product of the body that is secreted by the kidneys through a process called urination and excreted through the urethra. Cellular metabolism generates numerous by-products, many rich in nitrogen, that require elimination from the bloodstream...
of these animals. In humans and higher apes, the metabolic pathway for conversion of
uric acidUric acid is a heterocyclic compound of carbon, nitrogen, oxygen, and hydrogen with the formula C5H4N4O3. It forms ions and salts known as urates and acid urates such as ammonium acid urate. Uric acid is created when the body breaks down purine nucleotides. High blood concentrations of uric acid...
to allantoin is not present, so the former is excreted. Recombinant
rasburicaseRasburicase is a recombinant version of a urate oxidase enzyme that occurs in many mammals but not in humans.-Uses:Rasburicase is approved for use by the U.S...
is sometimes used as a drug to catalyze this metabolic conversion in patients. In fish, allantoin is broken down further (into
ammoniaAmmonia is a compound of nitrogen and hydrogen with the formula . It is a colourless gas with a characteristic pungent odour. Ammonia contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to food and fertilizers. Ammonia, either directly or...
) before excretion. Allantoin is a major metabolic intermediate in many other organisms including plants and bacteria.
Applications
Allantoin is present in botanical
extractAn extract is a substance made by extracting a part of a raw material, often by using a solvent such as ethanol or water. Extracts may be sold as tinctures or in powder form....
s of the
comfreyComfrey is an important herb in organic gardening. It is used as a fertilizer and also has many purported medicinal uses...
plant and
urineUrine is a typically sterile liquid by-product of the body that is secreted by the kidneys through a process called urination and excreted through the urethra. Cellular metabolism generates numerous by-products, many rich in nitrogen, that require elimination from the bloodstream...
from cows and most mammals. Chemically synthesized bulk allantoin is nature-identical, safe, non-toxic, compatible with cosmetic raw materials and meets CTFA and JSCI requirements. Over 10,000 patents reference allantoin. Manufacturers cite several beneficial effects for allantoin as an active ingredient in over-the-counter cosmetics: a moisturizing and
keratolyticKeratolytic therapy is treatment to remove warts and other lesions in which the epidermis produces excess skin. In this therapy, acid medicine, such as salicylic acid is put on the lesion. Keratolytic therapy thins the skin on and around the lesion. It causes the outer layer of the skin to loosen...
effect, increasing the water content of the
extracellular matrixIn biology, the extracellular matrix is the extracellular part of animal tissue that usually provides structural support to the animal cells in addition to performing various other important functions. The extracellular matrix is the defining feature of connective tissue in animals.Extracellular...
and enhancing the
desquamationDesquamation , also called skin peeling, is the shedding of the outermost membrane or layer of a tissue, such as the skin.-Skin:Normal, nonpathologic desquamation of the skin occurs when keratinocytes, after moving apically over about 14 days, are individually shed unnoticeably...
of upper layers of dead skin cells, increasing the smoothness of the skin; promoting cell proliferation and wound healing; and a soothing, anti-irritant, and skin protectant effect by forming complexes with irritant and sensitizing agents. A study published in 2009 reported the treatment of pruritus in mild-to-moderate atopic dermatitis with a topical non-steroidal agent containing Allantoin.
It is frequently present in
toothpasteToothpaste is a paste or gel dentifrice used with a toothbrush as an accessory to clean and maintain the aesthetics and health of teeth. Toothpaste is used to promote oral hygiene: it serves as an abrasive that aids in removing the dental plaque and food from the teeth, assists in suppressing...
,
mouthwashMouthwash or mouth rinse is a product used to enhance oral hygiene. Some manufacturers of mouthwash claim that antiseptic and anti-plaque mouth rinse kill the bacterial plaque causing cavities, gingivitis, and bad breath. Anti-cavity mouth rinse uses fluoride to protect against tooth decay...
, and other
oral hygieneTeeth cleaning is part of oral hygiene and involves the removal of dental plaque from teeth with the intention of preventing cavities , gingivitis, and periodontal disease. People routinely clean their own teeth by brushing and interdental cleaning, and dental hygienists can remove hardened...
products, in
shampooShampoo is a hair care product used for the removal of oils, dirt, skin particles, dandruff, environmental pollutants and other contaminant particles that gradually build up in hair...
s,
lipstickLipstick is a cosmetic product containing pigments, oils, waxes, and emollients that applies color, texture, and protection to the lips. Many varieties of lipstick are known. As with most other types of makeup, lipstick is typically, but not exclusively, worn by women...
s, anti-acne products, sun care products, and clarifying lotions, various cosmetic lotions and creams, and other cosmetic and pharmaceutical products.
See also
- Imidazolidinyl urea
Imidazolidinyl urea is an antimicrobial preservative used in cosmetics . It is chemically related to diazolidinyl urea which is used in the same way. Imidazolidinyl urea acts as a formaldehyde releaser.- Safety :...
and diazolidinyl ureaDiazolidinyl urea is an antimicrobial preservative used in cosmetics. It is chemically related to imidazolidinyl urea which is used in the same way. Diazolidinyl urea acts as a formaldehyde releaser....
, antimicrobialAn anti-microbial is a substance that kills or inhibits the growth of microorganisms such as bacteria, fungi, or protozoans. Antimicrobial drugs either kill microbes or prevent the growth of microbes...
condensation products of allantoin with formaldehydeFormaldehyde is an organic compound with the formula CH2O. It is the simplest aldehyde, hence its systematic name methanal.Formaldehyde is a colorless gas with a characteristic pungent odor. It is an important precursor to many other chemical compounds, especially for polymers...