ANALYSIS OF THE ASH OF THE CASTOR BEAN 



MARSTON LOVELL HAMLIN 

 (Harriman Research Lahoratory, Roosevelt Hospital, New York) 



In the discussion, following the presentation at the February 

 meeting of the Columbia University Biochemical Association, of the 

 results of investigations conducted in this laboratory on the effect of 

 manganous sulfate on the action of lipase in the castor bean, 

 Ricinus communis,'^ Professor Gies suggested that the effect pro- 

 duced in vitro by comparatively large amounts of manganese was 

 very possibly induced in the plant by much smaller amounts, and 

 that it would be of particular interest to test the ash of the seed for 

 its presence.^ The ash of the seed was therefore tested for man- 

 ganese ; and, at the same time, silica, magnesia, lime and phosphoric 

 acid were determined. 



A sample of the kerneis of the seed, cold-pressed, ground, ex- 

 haustively extracted with ether, as for use in lipolytic experiments,^ 

 and dried in vacuo over sulfuric acid, was slowly ignited in a 

 platinum dish. The black residue was treated several times with 

 nitric acid and re-ignited tili free from carbon. The residue was 

 weighed, taken up with water and nitric acid, and the Solution 

 filtered. Calcium sulfate was precipitated in the filtrate by sulfuric 

 acid and alcohol; and, in the filtrate from this precipitate, mag- 

 nesium and phosphorus were determined in separate aliquot parts, 

 each as magnesium pyrophosphate.* 



Of the powdered kerneis, 4.7698 grams gave 0.3483 gram of 

 ash, or 7.3 per cent. Of this, 0.0018 gram was insoluble and 



*Falk and Hamlin : Jour. Amer. Chem. Soc., 1913, xxxv, p. 210. An abstract 

 of this paper appears in this issue of the Biochemical Bulletin (p. 455). 



' The importance of infinitesimal amounts of manganese in plant growth has 

 been repeatedly pointed out by G. Bertrand. For a recent presentation of his 

 views, see his general lecture delivered before the Eighth International Congress 

 of Applied Chemistry, New York, September, 1912. 



* Falk and Hamlin : Loc. cit. 



* Abderhalden : Handbuch der bioch. Arbeitsmeth., 1912, vi, p. 381. 



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