Allantoin

History

Allantoin was first isolated in 1800 by the Italian physician Michele Francesco Buniva (1761–1834) and the French chemist Louis Nicolas Vauquelin, who mistakenly believed it to be present in the amniotic fluid.See:

• Buniva and Vauquelin (1800) "Sur l'eau de l'amnios de femme et de vache" (On the amniotic fluid of women and cows), Annales de chimie, 33 : 269-282.
• See also: Leopold Gmelin with Henry Watts, trans., Hand-book of Chemistry (London, England: The Cavendish Society, 1856), vol. 10, p. 260. In 1821, the French chemist Jean Louis Lassaigne found it in the fluid of the allantois; he called it "l'acide allantoique". In 1837, the German chemists Friedrich Wöhler and Justus Liebig synthesized it from uric acid and renamed it "allantoïn".See:
• Liebig and Wöhler (1837) "Ueber die Natur der Harnsäure" (On the nature of uric acid), Annalen der Physik und Chemie, 41 (8) : 561-569. Allantoin is named on p. 563. From p. 563: "Sie sind Allantoïssäure, oder dieselbe Substance, die man in der Allantoïsflussigkeit der Kühe gefunden hat; wir werden sie von nun an Allantoïn nennen." (They [i.e., the crystals previously isolated] are allantois acid, or the same substance that one found in the allantois fluid of cows; we will call it "allantoin" from now on.)
• Reprinted in: F. Wöhler and J. Liebig (1838) "Untersuchungen über die Natur der Harnsäure" (Investigations into the nature of uric acid), Annalen der Pharmacie, 26 : 241-340.

Animals

Named after the allantois (an amniote embryonic excretory organ in which it concentrates during development in most mammals except humans and other hominids), it is a product of oxidation of uric acid by purine catabolism. After birth, it is the predominant means by which nitrogenous waste is excreted in the urine of these animals. In humans and other higher apes, the metabolic pathway for conversion of uric acid to allantoin is not present, so the former is excreted. Recombinant rasburicase is sometimes used as a drug to catalyze this metabolic conversion in patients. In fish, allantoin is broken down further (into ammonia) before excretion.

Allantoin has been shown to improve insulin resistance when administered to rats and to increase lifespan when administered to the nematode worm Caenorhabditis elegans.

Bacteria

In bacteria, purines and their derivatives (such as allantoin) are used as secondary sources of nitrogen under nutrient-limiting conditions. Their degradation yields ammonia, which can then be utilized. For instance, Bacillus subtilis is able to utilize allantoin as its sole nitrogen source.

Mutants in the B. subtilis pucI gene were unable to grow on allantoin, indicating that it encodes an allantoin transporter.

In Streptomyces coelicolor, allantoinase (EC 3.5.2.5) and allantoicase (EC 3.5.3.4) are essential for allantoin metabolism. In this species the catabolism of allantoin, and the subsequent release of ammonium, inhibits antibiotic production (Streptomyces species synthesize about half of all known antibiotics of microbial origin).

Applications

Allantoin is present in botanical extracts of the comfrey plant and in the urine of most mammals. Chemically synthesized bulk allantoin, which is chemically equivalent to natural allantoin, is safe, non-toxic, compatible with cosmetic raw materials and meets CTFA and JSCI requirements. Over 10,000 patents reference allantoin.

Cosmetics

Manufacturers may use allantoin as an ingredient in over-the-counter cosmetics for its antioxidant, anti-inflammatory and moisturizing properties. It is a Humectant and hygroscopic, which make it a good moisturizer. It can also counteract other agents that may cause dryness like alcohols, sulfates, and fragrances.

Pharmaceuticals

Its anti-bacterial, exfoliating, anti-aging, and moisturizing properties make it useful in toothpaste, mouthwash, and other oral hygiene products, in shampoos, lipsticks, anti-acne products, sun care products, and clarifying lotions, various cosmetic lotions and creams, and other cosmetic and pharmaceutical products.

Biomarker of oxidative stress

Since uric acid is the end product of the purine metabolism in humans, only non-enzymatic processes with reactive oxygen species will give rise to allantoin, which is thus a suitable biomarker to measure oxidative stress in chronic illnesses and senescence.

References

References

1. "Allantoin".
2. "CAS # 97-59-6, Allantoin, 5-Ureidohydantoin, Glyoxyldiureide, Glyoxylic diureide, Cordianine, Glyoxyldiureid, (2,5-Dioxo-4-imidazolidinyl)urea".
3. (1996-08-09). "Labelling of uric acid and allantoin in different purine organs and urine of the rat". Life Sciences.
4. (2000-10-01). "Purine catabolism in ''Escherichia coli'' and function of xanthine dehydrogenase in purine salvage". Journal of Bacteriology.
5. (2009-01-01). "Lessons from comparative physiology: could uric acid represent a physiologic alarm signal gone awry in western society?". Journal of Comparative Physiology B.
6. Warr, L.N.. (2021). "IMA-CNMNC approved mineral symbols". Mineralogical Magazine.
7. Lassaigne (1821) [http://babel.hathitrust.org/cgi/pt?id=uva.x002488783;view=1up;seq=297 "Nouvelles recherches sur la composition les eaux de l'allantoïde et de l'amnios de la vache"] (New investigations into the composition of the allantoic and amniotic fluids of the cow), ''Annales de chimie et de physique'', 2nd series, '''17''' : 295-305. On pp. 300 ff, Lassaigne names and characterizes "l'acide allantoique" (allantoic acid).
8. (1944). "The absorption and excretion of allantoin in mammals". J. Pharmacol. Exp. Ther..
9. Fujiwara, S. (1995). "Degradation of purines: only ureidoglycollate lyase out of four allantoin-degrading enzymes is present in mammals". The Biochemical Journal.
10. (2008). "Activation of I₂-imidazoline receptors may ameliorate insulin resistance in fructose-rich chow-fed rats". Neuroscience Letters.
11. (2016). "A network pharmacology approach reveals new candidate caloric restriction mimetics in ''C. elegans''". Aging Cell.
12. (2016-05-01). "Allantoin transport protein, PucI, from ''Bacillus subtilis'': evolutionary relationships, amplified expression, activity and specificity". Microbiology.
13. (2008-02-26). "Reconstruction and analysis of the genetic and metabolic regulatory networks of the central metabolism of Bacillus subtilis". BMC Systems Biology.
14. (2001-06-01). "Functional analysis of 14 genes that constitute the purine catabolic pathway in ''Bacillus subtilis'' and evidence for a novel regulon controlled by the PucR transcription activator". Journal of Bacteriology.
15. (2013-11-29). "Allantoin catabolism influences the production of antibiotics in ''Streptomyces coelicolor''". Applied Microbiology and Biotechnology.
16. (May 2019)
17. Becker, Lillian C.. (2010). "Final Report of the Safety Assessment of Allantoin and Its Related Complexes". International Journal of Toxicology.
18. Javdan, Bahar. (August 8, 2024). "The validity of over-the-counter skin, hair, and nail recommendations for adult patients with cancer: A systematic review". Supportive Care in Cancer.
19. Bergfeld MD, Wilma. (2 August 2024). "What Is Allantoin? And What Does It Do for Your Skin (and More)?". Cleveland Clinic.
20. Thornfeldt, C. (2005). "Cosmeceuticals containing herbs: fact, fiction, and future". Dermatologic Surgery.
21. (2008). "Allantoin as a marker of oxidative stress in human erythrocytes". Clinical Chemistry and Laboratory Medicine.
22. (2004). "Uric acid and allantoin levels in Down syndrome: Antioxidant and oxidative stress mechanisms?". Clinica Chimica Acta.