576 INDIAN MEDICINAL PLANTS. 



is also stated that the milky juice of the plant is applied locally 

 to the os uteri, with the view of inducing abortion. Facts in 

 support of the alleged emmenagogue properties of the papaw are 

 still wanting. It is not within the scope of this work .to con- 

 sider the alleged power of the juice of the papaw to lessen the 

 cohesion of the muscular fibre, or, in homely language, to render 

 tough meat tender. The subject, which is discussed in extenso 

 by Sir W. J. Hooker {Bot. Mag. Nos. 2998 and 2999), Dr. Wight 

 (Illust.y vol. ii., p. 34, et seq.), and Dr. John Davy (Edin. Med. 

 Phil. Mag., Oct., 1855) must still be regarded as sub-judice. 

 (Ph. Ind.). 



Papaw leaves contain an alkaloid Carpaine, which has 

 been used as a heart tonic and febrifuge. 



From Papaw juice is extracted Papain, which is a white, 

 or whitish, amorphous powder, possessing a solvent action on 

 animal proteids.- A five per cent, solution of Papain is stated 

 to dissolve false membrane in diphtheria, and to be a good 

 application to warty epitheliomatous growths. 



Injections of -J-2 grains and upwards have been success- 

 fully used in scirrus and other malignant tumours {B. M. J. 

 1906, Vol. L, p. 1439 et seq., also 1907, Vol. I. p. 135). 



The leaves contain an alkaloid Carpaine,* which crystallises in anhydrous, 

 colourless, lustrous prisms melting at 121°, and resolidifies at about 90°; on 

 further heating, it undergoes partial decomposition, some subliming in 

 colourless needles. The alkaloid is extremely soluble in chloroform and 

 carbon bisulphide, more sparingly in light petroleum and alcohol, and in- 

 soluble in water; in alcoholic solution it is dextrorotatory, [a]D=+21'55°. 

 The base does not give a colour reaction with sulphuric acid either alone or 

 in presence of bromine water or vanadic anhydride ; with potassium 

 chromate and sulphuric acid, a green coloration is produced, nitric acid 

 gives no reaction. The formula of the alkaloid, is 14 H 25 N0 2 . 



Carpaine does not react with benzoic chloride or acetic chloride, but, 

 on treatment with acetic anhydride, a compound is formed which has not 

 yet been investigated. Ammonia and an acid free from nitrogen are formed 

 by the oxidation of carpaine with sulphuric acid and potassium permanganate. 

 —J. Ch. S. LX1V. at I. 1893, pp. 740-741. 



On methylation, carpaine yields methylcarpaine, crystallising from dilute 

 alcohol in small colourless prisms, melting at 71°, benzoylation of nitrosocar- 



* The alkaloid is contained in leaf epidermis and to a lesser extent in the 

 underlying parenchyma, epidermis of leaf stalk. 



