185 



III. THE VEGETABLE TOXINES 

 (PHYTOTOXINES). 



RICINE. 



The seeds of the castor-oil plant, Ricinus communis. produce 

 an extremely virulent poison, which is in every way closely 

 allied to the bacterial toxines. It is present in the embryo 

 endosperm but not in the husk (WERNER). Poisons with 

 completely analogous action are also present, according to 

 SxiLLMARK, 1 in ten other kinds of Ricinus viz., R. sanguineus, 

 africanus, guyanensis nanus, altissimus, communis major, philip- 

 pinensis, brasiliensis, borboniensis arboreus, spectabilis, and jam- 

 aicensis. The seeds of Jatropha curcas (Curcas purgans), a West 

 Indian Euphorbiaceous plant, popularly termed the "purging 

 nut" or "Barbadoes seed," also yield a toxic product which is 

 possibly identical with ricine (STILLMARK). 



Ricine was first investigated by DixoN. 2 He prepared a 

 poisonous product either by extracting the seeds with hydro- 

 chloric acid and precipitation with a solution of soda, or by 

 precipitating the substance from an aqueous extract by means 

 of alcohol. It was obtained in a purer state by treating the 

 aqueous extract with lead acetate and ammonia, suspending 

 the precipitate in water and removing the lead by means of 

 hydrogen sulphide, and then precipitating the toxine with 

 alcohol. In addition to the toxine a non-poisonous glucoside 

 was also detected in the seeds. 



Ricine was more thoroughly studied by SxiLLMARK, 1 working 

 under the direction of RUDOLF KOBERT. He extracted the seed 

 with a 10 per cent, solution of ordinary salt, treated the extract 

 with sodium or magnesium sulphate, and removed the salts by 

 means of dialysis. The yield amounted to 2-8 per cent., calcu- 

 lated on the decorticated air-dried seeds. 



CRUZ S washed the crushed seeds with chloroform and alcohol, 



1 Stillmark, "Ueber Eicin," Arb. pharm. Inst. Dorpat, iii., 59, 1889 

 ^ contains a complete bibliography of the earlier literature on the castor-oil 

 plant). 



2 Dixon, Australian Med. Gaz., 1887, 156, quoted by Cushny (vide infra). 



3 Cruz, "La ricine," Ann. d'Hyg. PubL, xl., 344, 1898. 



