74 



Prof. J. Reynolds Green and Mr. H. Jackson. [Mar. 22, 



posed gradually but fairly rapidly during the germination, and in the later 

 stages contribute to the acidity of the cell-sap, which contains phosphoric 

 acid. 



Search was made in a mass of endosperms for cholin. The germinating 

 seeds were ground up in a mortar and allowed to stand for some days under 

 alcohol which was nearly absolute. This was decanted and evaporated to 

 dryness, the residue being again extracted with absolute alcohol and 

 subsequently by a mixture of alcohol and ether. These extracts were 

 mixed and evaporated to dryness, leaving a final residue, soluble in water. 

 When a strong aqueous solution of this was boiled, decomposition took place, 

 and a gas was evolved which possessed the well-known ammoniacal and 

 fishy odour characteristic of tri-methylamine. The decomposition can be 

 represented by the following equation : — 



CH 2 (OH)CH 2 N(CH 3 ) 3 OH = CH 2 (OH)CH 2 OH + N(CH 3 ) 3 . 



When to some of an aqueous solution of the residue from the alcoholic and 

 ethereal extracts a little platinic chloride was added, after standing for some 

 time the characteristic yellow octahedral crystals of the compound which 

 cholin forms with platinic chloride separated out. These were soluble in 

 15 per cent, alcohol, and on combustion yielded a residue of metallic 

 platinum. We have thus all the constituents of lecithin present in the 

 germinating seeds. 



It was difficult to apply the ordinary tests for lecithin when so large 

 a quantity of oil was present. Towards the close of the germination, 

 however, conditions were more favourable, the lecithin being present in 

 relatively large proportion. 



The existence of a proteolytic enzyme of a tryptic nature in the 

 germinating seeds was shown in the former paper. Among the products of 

 its action a considerable quantity of crystalline amino-bodies were detected, 

 though not sufficient for a complete analysis. They separated out from the 

 concentrated alcoholic extracts, after removal of the sugars, in quantities 

 that enabled their amino-nature to be proved. The power of the enzyme to 

 produce these in vitro has already been noted.* We have found the cholin 

 also to be due to the action of this enzyme. 150 cc. of an extract of the 

 endosperms of a quantity of germinating seeds was prepared by steeping 

 them for several hours in water containing 0'2 per cent, of formaldehyde as 

 an antiseptic. It was then strained through muslin and filtered till it 

 appeared as a clear straw-coloured liquid. This was divided into two, and 

 half of it boiled ^to destroy the protease. A quantity of globulin was 



* Green, loc. cit., p. 377. 



