Tannins termed

Min, B. R., Pomroy, W. E., Hart, S. P. and Sahlu, T. (2004). The effect of short-term consumption of a forage containing condensed tannins on gastro-intestinal nematode parasite infections in grazing wether goats . Small Ruminant Research, 44, 81-87. 

Controversy has arisen at times [52] regarding the apparent synonymity of the terms basic dye and cationic dye . The Society of Dyers and Colourists defines a basic dye as characterised by its substantivity for the acidic types of acrylic fibres and for tannin-mordanted cotton , whereas a cationic dye is defined as one that dissociates in aqueous... 

The term, complex tannin, appears to be established as descriptor for the class of polyphenols in which a flavan-3-ol unit, representing a constituent unit of the condensed tannins (proanthocyanidins), is connected to a hydrolyzable (gallo-or ellagi-) tannin through a carbon-carbon linkage. Since the first demonstration of their natural occurrence, a considerable number of these unique secondary metabolites have been reported. " New additions (Table 11.17) to this series of compounds come exclusively from the groups of Nonaka and Nishioka, and Okuda and Yoshida in Japan. 

On, ok Chamois Leather—TIiIb article, takes its name from the skins of the chamois but, although the term is still retained, those of sheep, deer, lambs, and the tliin portion of split hides and skins, are now converted into it. It is different from any of the varieties hitherto described, bcoause neither tannin nor mineral matters enter Into its formation the conservation being entirely effected by means of oils and fats. Further, the finest, aB well as tire coarsest quality known as wash-leather, receive precisely the same treatment, and consequently the difference they present is owing to the circumstance, that the finest skins are chosen for tho former, whilst the inferior ones are mado into the latter. In the last, sixteenth, and earlier centuries, the trade in chamois leather was much more considerable than at prosent because, in those periods, it was extensively used for clothing, particularly in the armies. It is now, however, abandoned for this purpose, in consequence of its permeability, owing to which it readily absorbed moisture, and parted with it bnt slowly qualities which kept the wearer in continual. danger of cold and rheumatic complaints. 

Ink (melanos) was made from lampblack or soot from burning resins, mixed with gum or glue. Dioscorides mentions that chalcanthum is added. This addition is difficult to understand. Chalcanthum as we have seen was a term including copper sulphate, ferrous sulphate and mixtures of the two. If a solution of nutgalls or other solution of tannin were used, the addition would be comprehensible... 

While tannins probably vary in composition, the type generally termed tannic acid is a pentadigalloylglucose for hydrolysis yields diagallic add and glucose. 

Benefits The caffeine content makes guarana a strong central nervous system stimulant. It is traditionally used as a tonic for fatigue and to allay hunger and thirst. It also has short-term diuretic effects. The tannin content gives guarana an astringent effect and it has been used to treat diarrhoea. 

---