Allantoin is a natural  compound and a major metabolic intermediate in most living organisms, including bacteria, fungi,  animals.and in a genus of plants of the Dioscoreaceae family, a rather large family, with about 600 species. Generally, the plant is called yam. The major constituents of yam are allantoin, dioscorin, sapogenins, prosapogenin, gracillin, choline, l-arginine, polysaccharides, and proteins (1). This plant and in particular its rhizome, is used in the medical field for the prevention of inflammation and ulcers (2) and it has been used to improve diabetic disorders (3). 

It is a diuretic chemical compound (substance in which the molecule contains twice the bivalent radical from urea) of glyoxylic acid.

As an industrial chemical compound, it appears as a white crystalline powder, odorless, .slightly soluble in water and alcohol, insoluble in ether and chloroform and other organic solvents.

What it is used for and where

Medical

 The aims of this study are to investigate the antioxidant and antitumor activities of the water and ethanol extracts isolated from Chinese yam (Dioscorea opposite Thunb.) flesh (CYF) and peel (CYP) and the effective compounds. this study demonstrated that CYP-W exerted better antitumor activity than flesh extracts and the scavenging ROS effects were also significantly higher in the CYP-W in vitro. Moreover, the data indicated that allantoin may play an important role on antioxidative and antitumor capacity in yam peel (4).

 Reducing post-interventional inflammation and pain in odontostomatological surgery procedures, such as tooth extractions, implants or oral biopsies is a relevant clinical goal. Chlorhexidine oral rinse is commonly used with this aim. Recently a new product containing chlorhexidine, dexpanthenol, allantoin and chitosan (Bexident Post [BP]) in a gel formulation has been developed. We evaluated the efficacy of BP in controlling postsurgical inflammation and pain and in promoting cicatrization in subjects undergoing molar extractions. In this trial BP performed better than bicarbonate  in controlling pain and inflammation in subjects undergoing dental surgery, reducing the consumption of analgesics and favoring better cicatrization (5).

Allantoin is used to treat dermatitis, redness, acne, eczema and in some burns. Its efficacy has been established in wound healing and in improving pigmentation and flexibility of scars (6).

Cosmetics

Allantoin promotes cell growth by increasing the water content of the skin's extracellular matrix, which leads to an overall improvement in the condition of the skin, which remains more moisturised and resistant. It also has good exfoliating properties and can remove dead cells in, for example, face washing.

 Plants that contain Allantoin:

• Symphytum officinale 
• Dioscorea polystachya
• Dioscorea oppositifolia
• Dioscorea bulbifora
• Memora nodosa (Silva Manso)
• Miers (Bignoniaceae)

For more information:      Allantoin studies

Typical commercial product characteristics Allantoin

Appearance	White powder,  white crystals
pH	4.00-6.00
Boiling Point	478°C
Melting Point	230°C
Flash Point	230-234°C
Density	1.7±0.1 g/cm3
Refraction Index	1.616
PSA	113.32000
LogP	-2.89
Heavy metals	10min mg/kg
Loss on drying	＜0.10%
Burnt residue	0.10 %
Ash	＜0.10%
Sulfate	≤ 10ppm
Optical rotation	-0.1° － +0.1°
Molds and Yeast	73.50max cfu/g
Aerobic Bacterial	50max cfu/g
Chemical Risk

 Price

25 g    $21.80

100 g  $29,30

• Molecular formula   C₄H₆N₄O₃ 
• Molecular weight   158.12
• Exact Mass    158.043991
• CAS   97-59-6     
• UNII    
• EC Number   202-592-8
• DSSTox Substance ID  DTXSID3020043
• IUPAC  (2,5-dioxoimidazolidin-4-yl)urea
• InChl=1S/C4H6N4O3/c5-3(10)6-1-2(9)8-4(11)7-1/h1H,(H3,5,6,10)(H2,7,8,9,11)
• InChl Key      POJWUDADGALRAB-UHFFFAOYSA-N
• SMILES   C1(C(=O)NC(=O)N1)NC(=O)N
• MDL number  MFCD00005260
• PubChem Substance ID    329748141
• ChEBI   15676
• RTECS  YT1600000
• NCACRES NA.22
• NSC      757792    7606

Synonyms :

• 5-ureidohydantoin
• Glyoxylic(acid) diureide
• 5-Ureidohydantoin
• (2,5-dioxoimidazolidin-4-yl)urea
• Psoralon
• 5-Ureido-2,4-imidazolidindion
• 1-(2,5-dioxoimidazolidin-4-yl)urea
• 2,5-dioxo-4-imidazolidinyl urea
• 1-(2,5-Dioxo-4-imidazolidinyl)urea
• Urea, N-(2,5-dioxo-4-imidazolidinyl)-
• Sebical
• 4H-imidazole-2,5-diol, 4-[(hydroxyiminomethyl)amino]-
• Urea, (2,5-dioxo-4-imidazolidinyl)-

References_____________________________________________

(1)   Zhang L., Liu Y., Chen G. Simultaneous determination of allantoin, choline and l-arginine in Rhizoma Dioscoreae by capillary electrophoresis. J. Chromatogr. A. 2004;1043:317–321. doi: 10.1016/j.chroma.2004.06.003. 

(2)  Biological functions of allantoin Shestopalov AV, Shkurat TP, Mikashinovich ZI, Kryzhanovskaia IO, Bogacheva MA, Lomteva SV, Prokof'ev VP, Gus'kov EP   Izv Akad Nauk Ser Biol. 2006 Sep-Oct; (5):541-5. 

(3)  Go HK, Rahman MM, Kim GB, Na CS, Song CH, Kim JS, Kim SJ, Kang HS.Nutrients. 2015 Oct 15;7(10):8532-44. doi: 10.3390/nu7105411. Antidiabetic Effects of Yam (Dioscorea batatas) and Its Active Constituent,    Allantoin, in a Rat Model of Streptozotocin-Induced Diabetes.

(4)  Antioxidant and Antitumor Activities of the Extracts from Chinese Yam (Dioscorea opposite Thunb.) Flesh and Peel and the Effective Compounds. Liu Y, Li H, Fan Y, Man S, Liu Z, Gao W, Wang T.   J Food Sci. 2016 Jun;81(6):H1553-64. doi: 10.1111/1750-3841.13322. Epub 2016 Apr 27.

(5)  Efficacy of chlorhexidine, dexpanthenol, allantoin and chitosan gel in comparison with bicarbonate oral rinse in controlling post-interventional inflammation, pain and cicatrization in subjects undergoing dental surgery.  Lopez-Lopez J, Jan-Pallí E, lez-Navarro BG, Jané-Salas E, Estrugo-Devesa A, Milani M.  Curr Med Res Opin. 2015 Dec;31(12):2179-83. doi: 10.1185/03007995.2015.1108909. Epub 2015 Nov 4. Erratum in: Curr Med Res Opin. 2016;32(2):395. Lope-Lopez, Jose [corrected to Lopez-Lopez, Jose]; González-Navarro, Beatriz [corrected to lez-Navarro, Beatriz Gonzá].

 (6) Conti V, Corbi G, Iannaccone T, Corrado B, Giugliano L, Lembo S, Filippelli A, Guida M. Effectiveness and Tolerability of a Patch Containing Onion Extract and Allantoin for Cesarean Section Scars. Front Pharmacol. 2020 Sep 25;11:569514. doi: 10.3389/fphar.2020.569514.