Tannic acid is a phenolic acid, a naturally occurring polyphenol. It has antibacterial and antiviral properties and has been successfully used to combat HIV, Gram-positive and Gram-negative bacteria, Papilloma virus, Herpes simplex virus types 1 and 2, SARS-CoV-2 (by dual inhibition of the viral major protease and the cellular protease TMPRSS2) (1) and others. It basically prevents viral entry into cells.

Tannic acid statistically improved recovery after warm ischemia but not after cold ischemia, and this study concluded that tannic acid was able to improve renal recovery after warm renal ischemia with an antioxidant effect presumably extended by the production of its derivatives in the body and promoted cell regeneration during hypoxia. Hot ischemia and cold ischemia require specific therapeutic strategies (2).

Tannic acid may contribute to the treatment of inflammation by decreasing myeloperoxidase enzyme activity (3) and plays an important role as a biomaterial because it can capture free radicals and form complexes with metal ions.

Higher concentrations of tannic acid could reduce activated partial thromboplastin and plasma prothrombin times, and various concentrations of tannic acid could affect reaction time, clotting time, clot aggregation rate, and maximum clot strength of whole blood coagulation. These results provide a basis for the design of tannic acid molecules and its possible application in biomedicine (4) and with particular regard to wound healing (5).

Excessive exposure to UV radiation is a major factor in skin aging, erythema, burns and skin cancer. Two natural materials, hyaluronic acid and tannic acid have shown broad-spectrum UV protection, excellent adhesion to the skin surface, antioxidant activity, cooling effect and high moisture content (6).

Tannic acid studies

Molecular Formula: C₇₆H₅₂O₄₆

Molecular Weight: 1701.2

CAS: 1401-55-4

UNII 28F9E0DJY6

EC Number: 215-753-2    226-562-9 

DSSTox Substance ID: DTXSID2026076

MDL number  MFCD00066397

PubChem Substance ID 329751222

NACRES: NA.24

Beilstein/REAXYS Number: 8186396

Synonym:

• Tannin
• Tannins
• Gallotannic acid
• Gallotannin

References________________________________________________________________________

(1) Wang SC, Chen Y, Wang YC, Wang WJ, Yang CS, Tsai CL, Hou MH, Chen HF, Shen YC, Hung MC. Tannic acid suppresses SARS-CoV-2 as a dual inhibitor of the viral main protease and the cellular TMPRSS2 protease. Am J Cancer Res. 2020 Dec 1;10(12):4538-4546.

(2) Alechinsky L, Favreau F, Cechova P, Inal S, Faye PA, Ory C, Thuillier R, Barrou B, Trouillas P, Guillard J, Hauet T. Tannic Acid Improves Renal Function Recovery after Renal Warm Ischemia-Reperfusion in a Rat Model. Biomolecules. 2020 Mar 12;10(3):439. doi: 10.3390/biom10030439. 

(3) Soyocak A, Kurt H, Cosan DT, Saydam F, Calis IU, Kolac UK, Koroglu ZO, Degirmenci I, Mutlu FS, Gunes HV. Tannic acid exhibits anti-inflammatory effects on formalin-induced paw edema model of inflammation in rats. Hum Exp Toxicol. 2019 Nov;38(11):1296-1301. doi: 10.1177/0960327119864154.

(4) Deng L, Qi Y, Liu Z, Xi Y, Xue W. Effect of tannic acid on blood components and functions. Colloids Surf B Biointerfaces. 2019 Dec 1;184:110505. doi: 10.1016/j.colsurfb.2019.110505.

(5) Kaczmarek B, Mazur O, Miłek O, Michalska-Sionkowska M, Osyczka AM, Kleszczyński K. Development of tannic acid-enriched materials modified by poly(ethylene glycol) for potential applications as wound dressing. Prog Biomater. 2020 Sep;9(3):115-123. doi: 10.1007/s40204-020-00136-1.

(6) Gwak MA, Hong BM, Park WH. Hyaluronic acid/tannic acid hydrogel sunscreen with excellent anti-UV, antioxidant, and cooling effects. Int J Biol Macromol. 2021 Sep 29;191:918-924. doi: 10.1016/j.ijbiomac.2021.09.169.