CATECHU 335 



Constituents. Catechutannic acid, 25 (black catechu) or 22 to 

 50 per cent (pale catechu), giving a green color and precipitate with 

 solutions of ferric chloride and in other respects resembling the 

 tannin in oak bark, kino and krameria; a substance somewhat 

 resembling gallic acid, catechin, which crystallizes in silky needles; 

 catechu-red; quercetin and ash about 3 per cent. Pale catechu 

 contains in addition a fluorescent principle. 



Mangrove Extract. The bark of the red variety of Rhizophora 

 Mangle or R. mucronata (Fam. Rhizophoraceae), contains from 17 

 to 39 per cent of tannic acid. An extract is prepared and some- 

 times sold for catechu. It gives a green precipitate with solutions of 

 ferric salts; a reddish-black color with a solution of copper sulphate 

 and ammonia; a reddish-brown color with sulphuric acid; a reddish 

 precipitate with lime water, darkened by excess; and a slight redden- 

 ing with a solution of stannous chloride and hydrochloric acid. It 

 apparently belongs to the same class of tannins as hemlock, oak, 

 rhatany and canaigre. 



Allied Plants. Black catechu is also extracted from the wood of 

 Acacia Suma, of India. The barks of a number of species of Acacia 

 growing in Australia, and known as wattle barks, are used in the 

 preparation of an extract resembling black catechu. The tannin of 

 Acacia arabica and of several species of Caesalpinia yield on hydrolysis 

 gallic and ellagic acids. 



A tannin resembling catechu is obtained from the bark of Eugenia 

 Smithii (Fam. Myrtacese) of Australia. A catechu-like extract is 

 obtained from the bark of the Mahogany Tree (Swietenia Mahogoni), 

 one of the Melicese, of the West Indies and Central America. 



An extract (known as Than), prepared from Terminalia Oliveri 

 (Fam. Combretacese), a large tree growing in the dry regions of the 

 Irrawaddy Valley, is used to adulterate Catechu. It contains a dark- 

 red coloring principle, but apparently no tannin, although the latter 

 has been reported as occurring to the extent of between 14 and 68 

 per cent. 



Literature. Ridenour, Jour. Franklin Inst., 1903, p. 417. 



KINO. Malabar or East Indian Kino. The inspissated juice 

 of Pterocarpus Marsupium, and probably other species of Ptero- 

 carpus (Fam. Leguminosse, sub-fam. Papilionacese), trees indigenous 

 to southern India and Ceylon. The juice exudes through incisions 

 made in the bark, and is allowed to dry in the sun. The drug is 

 exported from Madras and is known as Malabar or East Indian Kino. 



Description. Small, angular, opaque, black or reddish-black, 

 translucent, glistening, brittle pieces, nearly free from dust; the 



