Natural Source of Tannin Acids

Tannin acid or tannins are a type of polyphenol, naturally occurring compounds found in many plants. The resulting liquid contains tannin-rich compounds which can then be used for various purposes, including tanning leather or producing dyes. Tannins are thought to have anti-inflammatory effects and antibacterial properties. It has been linked to reducing the risk of heart disease, cancer, and other diseases. Tannin acid is an important component in many food products due to its ability to add texture, body, and color. Tannins can also be used in winemaking as a preservative agent and to improve flavor. Natural tannins are generally regarded as safe due to their origin, do you know what’re their sources?

Tannin is a secondary metabolite derived from carbohydrate metabolism in nature, which is the product of plants and the environment in the long-term natural evolution process and is also the self-protection substance of plant species. Tannins are abundant in nature, second only to cellulose, hemicellulose and lignin. Tannins can be found in fruits, herbs, nuts, and vegetables as well as types of bark from trees. The tannin concentration of different species and different parts of plants varies greatly. Tannins are usually extracted from plant sources by steeping or soaking the plant material in hot water and the extracted condensed tannin content ranges from 0 to 196 g/kgDM.

Tannins are distributed in nature and deposited in any type of plant tissue, including fruits, stems, leaves, roots, etc. Herbs have the most tannins. For example: cornus fruit, rhubarb root, geranium, sanguisorba and both Polygonum bistorta and Polygonum multiflorum, myrobalans fruits (amla, Emblica officinalis), Chinese Polygonum multiflorum (heshouwu) and Rhodiola Root. Different parts of the plant contain different amounts of tannin:


Tannins are mainly found in the subcutaneous tissue under the cortex, which can be used as a defense against pathogens.


The stem is the part of tannin currently active growth, such as the secondary phloem, xylem, and layer between bark and epidermis, where it regulates epidermal tissue growth.


Tannins are located between the epidermal layer and the protein layer of the seed and help maintain the dormant period.

Fruits and leaves

The bitter taste of tannins reduces the appetite of herbivores and insects, so it is a natural line of defense. In nature, tannin content of some legumes and gramineous plants, weeds, shrubs and trees is higher, and changes with their growing environment

Source of tannins  Parts Applications
Acacia catechu gall Leaves cough, dysentery; topically for skin ulceration
Chinese cedar(Cedrela sinensis)  Root/bark dysentery,  functional bleeding, hematochezia, morbid leucorrhea, involuntary emission
Pomegranate Fruit chronic diarrhea and dysentery, functional bleeding, morbid leucorrhea, hematochezia, rectal prolapse, involuntary emission, intestinal parasites
Acorn(Quercus acutissima ) fruit diarrhea, rectal prolapse, hemorrhoidal bleeding
Oak gallnut(Quercus infectoria) Leaves red-white dysentery, hemorrhoids, rectal prolapse; hyperhidrosis, oral ulceration, leucorrhea, topically for skin lesions
Sumac gallnut (Rhus semialata) Leaves cough, rectal prolapse, functional bleeding; topically for wound bleeding, ulcerous dermatitis,spontaneous sweating, night sweating, epistasis, toxic skin swelling
Rosehips(Rosa laevigata) Fruit enuresis, frequent urination,, involuntary emission, morbid leucorrhea, persistent diarrhea
Chebulic myrobalan(Terminalia chebula ) Fruit chronic diarrhea and dysentery, hematochezia, leucorrhea, night sweating, rectal prolapse, aphonia due to longstanding cough, involuntary emission