**4. Leather industry**

In leather industry, tannins are generally used to convert animal hide into leather. Here, the main role of tannins is to protect leather from microorganism and heat related deterioration [47]. Tanning industry is thought to be the oldest industry and was started in north western regions of Europe after the Roman conquest [48]. Tannins bind with the skin proteins and protect it from petrification, which is owed to the antibacterial property of tannins. This is due to the chemical bonds established between collagen, the main constitutive protein of skin, for example,

**129**

wine [52].

**6. Future prospectus**

*Applications of Tannins in Industry*

*DOI: http://dx.doi.org/10.5772/intechopen.85984*

**5. Other industrial applications**

impediment in its further applications [51].

collagens, and the tannins present in the vegetable materials. It is estimated that about 15–45% tannins binds with collagens per dry weight. After the industrial revolution, chromium-based tanning was introduced to achieve fast and speedy leather production. But chromium is a potentially carcinogenic and creates high level of pollution and soil contamination. Additionally, it limits recovery and reuse of wastes from leather industries. Water from leather industry creates more pollution, and increase biological oxygen demand (BOD) and chemical oxygen demand (COD) in polluted water. In order to overcome this problem, plant-based tannins can be substitute for chromium in leather processing. It is already mentioned that vegetable tannins were used in the leather industry since historical times. But now, tannins from different parts of plants have been utilized in leather productions [49]. Plant tannins offer many benefits such as high quality and thermal stable leather products.

In addition to above mentioned applications, tannins are also used in diverse types of industries, such as paper industry where high pressure mimosa tannin impregnated alpha cellulose paper is prepared. This impregnated paper offer more abrasive resistance, adhesion properties, water vapor resistance, and staining properties [50]. Recently, natural tannin-based foam without any formaldehyde is prepared that used as acoustic absorbers, metal ion adsorption, panels crash protection, packaging, etc., but low mechanical strength of tannin foams is major

Beverage industry is well known for tannins applications particularly, in case of the wine making. Like leather industry, wine making is also very old industry since historic time. Tannins are used in wine to provide color formations, antioxidants, aroma, proteins precipitations, and flavor development. The source of tannins in the wine is grapes skin, seeds, and addition of oak flakes which add market values to

Tannins are phenolic-based secondary metabolites that are present in the plant kingdom, including algae. Actually, tannins produced in the plant body and involved in the plant protections and act as antimicrobial, antiparasitic, anthelmintic, antiviral, antioxidant, and deferred cattle. Hence, they help plants to fight various types' infections. In addition to biological roles, they also play very important roles in industrial sector, animal feeding, mining, chemical industry, and tanning industry. But there are several limitations associated with the tannins. The main negative effect of tannins as food is their absorptions and binding with various types of biomolecules such as proteins, starch, and metal ions in the digestive system, hence hinders their nutritional availability to human and animals, for example, proanthocyanidins. Some experiments show that complex of tannins and proteins are resistant to various types of proteases in animal digestive system that make proteins unavailable for livestock nutrition. Dietary tannins bind with the proline-rich proteins and as result two types of soluble and insoluble complexes formed which is responsible for astringent sensation [53]. The astringency feeling is perceived by the tongue in the form of diffuse feeling associated with extreme dryness and roughness in mouth [54]. Some experiments also show that tannins also decrease activities of intestinal microflora, consequently less absorption of

*Applications of Tannins in Industry DOI: http://dx.doi.org/10.5772/intechopen.85984*

*Tannins - Structural Properties, Biological Properties and Current Knowledge*

"is a means of cancer management by which the occurrence of the disease can be entirely prevented, slowed, or reversed via administration of one or more naturally occurring and/or synthetic compounds" [43]. Currently, target-based delivery of anticancer agents to the site of cancer or tumor is major challenge. In order to target tumor at nanolevel, cancer nanotechnology has made tremendous progress in last one decade. It is assumed that, if drug is delivered at nanolevel at site of tumor with a high level of specificity so that cancer can be better managed. Nanoparticles of various tannin-based compounds are also prepared but their toxicity to normal body cells left major side effects. Therefore, encapsulation of many types of tannin like, epigallocatechin-3-gallate in chitosan-tripolyphosphate nanoparticles was investigated for target-based delivery to tumor. It is well known that (−)-epigallocatechin-3-gallate, (−)-epigallocatechin, (−)-epicatechin-3-gallate and (−)-epicatechin act as anticancer and antioxidant agents. The nanoemulsions and liposomes of tannins have proven highly effective in target-based delivery of anticancer drugs in case of HepG2 cells [44]. So far, nanoencapsulation method is proved only in in vitro studies and animal models but it is rarely proved effective in normal and

In current era, viral infection is the major threat to the human and animal population. Tannins also show antiviral activity in case of several diseases such as HIV, herpes simplex virus 2 (HSV-2). In case of herpes simplex virus 2 silver nanoparticles with tannic acid (TA-AgNPs) act as microbicide by preventing adsorption of viral particle in the body. Additionally, tannins also provide the better adjutant properties for example, substantial improvement of production of IFN-gamma+ CD8+ T-cells, activated B cells, and plasma cells. In case of spleen also, tannins promotes production of higher amount of IFN-gamma+ NK cells and effector-memory CD8+ T-cells particularly, in case of second challenge against

Free-living protozoa species of *Acanthamoeba* genus generally cause significant

In leather industry, tannins are generally used to convert animal hide into leather.

Here, the main role of tannins is to protect leather from microorganism and heat related deterioration [47]. Tanning industry is thought to be the oldest industry and was started in north western regions of Europe after the Roman conquest [48]. Tannins bind with the skin proteins and protect it from petrification, which is owed to the antibacterial property of tannins. This is due to the chemical bonds established between collagen, the main constitutive protein of skin, for example,

infections of keratitis and encephalitis in human. Acanthamoeba keratitis is a cornea related infection that adversely affected eye vision. It is resistance to current available therapy. To overcome this problem, both pure silver and gold nanoparticle and tannic acid-modified of nanoparticles of silver and gold were prepared and their activities were tested against the clinical strains of *Acanthamoeba* spp. The tannic acid-modified nanoparticles proved more effective and less toxic to eye infection. Moreover, tannic acid-modified silver nanoparticles were well absorbed by the trophozoites eventually inhibits germination of cyst which is a major stage of life cycle of amoebae parasite [46]. So that it can be concluded that tannin-based

nanoparticles are more effective than pure silver and gold particle.

**128**

cancerous cells.

**3.1 Antiviral activity of tannin**

HSV-2 immune response [45].

**4. Leather industry**

collagens, and the tannins present in the vegetable materials. It is estimated that about 15–45% tannins binds with collagens per dry weight. After the industrial revolution, chromium-based tanning was introduced to achieve fast and speedy leather production. But chromium is a potentially carcinogenic and creates high level of pollution and soil contamination. Additionally, it limits recovery and reuse of wastes from leather industries. Water from leather industry creates more pollution, and increase biological oxygen demand (BOD) and chemical oxygen demand (COD) in polluted water. In order to overcome this problem, plant-based tannins can be substitute for chromium in leather processing. It is already mentioned that vegetable tannins were used in the leather industry since historical times. But now, tannins from different parts of plants have been utilized in leather productions [49]. Plant tannins offer many benefits such as high quality and thermal stable leather products.
