BRIEFER ARTICLES 



ARTIFICIAL PRODUCTION OF ALEURONE GRAINS 



(with one figure) 



As is well known, aleurone grains consist mainly of protein material 

 which may be wholly amorphous or partly amorphous and partly 

 crystalline. - In the latter case each grain consists typically of a crystal 

 of protein (crystalloid), and an envelope of amorphous protein material 

 whose outer layer may be differentiated from the rest. There is usually 

 included in the envelope a globule of mineral matter or organic material 

 combined with mineral matter (globoid). The variations occurring 

 in different plants have been fully described by Pfeffer. 1 



Each grain is laid down in a vacuole in the protoplasm through the 

 activity of the protoplasm itself. Its manufacture is therefore a dis- 

 tinctly vital process. It is the object of this paper to show that bodies of 

 the same structure may be produced artificially. The resemblance is 

 so striking as to leave little doubt that the essential features of the 

 natural process have been successfully imitated. 



The first step in the procedure is the preparation of protein accord- 

 ing to the following method of Osborne. 2 Half a pound of Bertkolletta 

 nuts, after the shells have been removed, are ground into a pulp. The 

 fatty material is then removed by repeated thorough treatments with 

 ether, the small portion of the solvent which remains in the solid after 

 the final decantation being allowed to evaporate completely. To the 

 dry residue is added four or five times its volume of 10 per cent NaCl 

 solution in which it stands some hours. Frequent shaking accelerates 

 the dissolving of the protein. The solution of protein is then decanted 

 and thoroughly filtered. At first the finer particles come through, 

 but on repeated filtering through the same paper there results an abso- 

 lutely clear liquid which microscopic examination shows to be without 

 particles of any kind. This clear filtrate is placed in a dialyzer, and 

 after some hours the sodium chloride is sufficiently removed to cause 

 the precipitation of the protein. 



Most of the protein is precipitated as clear, well formed crystals 

 of the hexagonal system. Their thickness is usually about one-sixth 



* Pfeffer, W., Jahrb. Wiss. Bot. 8: 429. 1872. 

 'Osborne, T. B., Amer. Chem. Jour. 14:622. 1892 



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