Tannins: Major Sources, Properties and Applications

Anticancer Agents: Saponin and Tannin

“…It was determined that tannins were exhibited anti-tumor and anticancer activity against to HeLa cell and murine leukemia cells (L1210/0), murine mammary carcinoma cells (FM3A) and human T-lymphocyte cells (Molt4/C8, CEM/0) (Pizzi, 2008).…”

Monomers and Resulting Polymers from Biomass

“…On a broader scale, tannins have some interesting properties that fit well with the goal of creating chemicals from biomass. Outside the scope of this chapter, tannins are used in the manufacture of leather, as wine, beer, and juice additives, as ore flotation agents, in cement as a superplasticizer, and more recently in pharmaceutical applications [163]. As a polymer tannins mostly find use in adhesives, in particular as a binder for wood where the condensation reaction between formaldehyde and tannin is exploited to form a thermosetting resin.…”

“…As a polymer tannins mostly find use in adhesives, in particular as a binder for wood where the condensation reaction between formaldehyde and tannin is exploited to form a thermosetting resin. The use of tannins in wood adhesives is well established and is not discussed here [163][164][165][166][167]. Recent work by Tondi et al has produced interesting results with regards to the condensation reaction between tannin and FA to produce a near completely biorenewable thermoset foam for applications in insulation, which is the focus of this discussion [168].…”

“…The two types of tannins are condensed and hydrolyzable; the latter constitutes less than 10% of the tannins produced and is therefore not discussed here [164]. Condensed tannins are natural products of the oligomerization of aromatic flavonoids, where the degree of oligomerization depends on the source of the flavonoids [163]. In mimosa and quebracho tannins, the number of flavonoid repeat units ranges between 2 and 11 with an average degree of polymerization between 4 and 5; for pine tannins the average degree of polymerization is higher (between 6 and 7) [163].…”

“…Condensed tannins are natural products of the oligomerization of aromatic flavonoids, where the degree of oligomerization depends on the source of the flavonoids [163]. In mimosa and quebracho tannins, the number of flavonoid repeat units ranges between 2 and 11 with an average degree of polymerization between 4 and 5; for pine tannins the average degree of polymerization is higher (between 6 and 7) [163]. Tannins are produced by a large number of woody plants and can be obtained through simple water extraction; common sources are the wood of quebracho, chestnut, and mangrove and the bark of oak, black wattle, black mimosa, and several species of pines and firs.…”