176 CHEMISTRY OF PLANT LIFE 



b. Peptones products of further hydrolysis soluble in water, not 



coagulated by heat, not precipitated by ammonium sulfate, 

 give biuret reaction. 



c. Peptides individual amino-acids, or poly-peptides, may or 



may not give biuret reaction. 



The plant proteins which have been investigated, thus far, 

 fall into these groups as follows: 



1A. Albumins 



Leucosin, found in the seeds of wheat, rye, and barley. 

 Legumelin, " pea, horse-bean, vetch, soy-bean, len- 



til, cowpea, adzuki-bean. 

 Phaselin, " kidney-bean. 



Ricin, castor-bean. 



IB. Globulins 



Legumin, found in the seeds of pea, horse-bean, lentil and vetch. 

 Vignin, cowpea. 



Glycinin, soy-bean. 



Phaseolin, beans (Phaseolus spp.) 



Conglutin, " lupines. 



Vicilin, pea, horse-bean, lentil. 



Corylin, hazel nut. 



Amandin, nuts of almond and peach. 



Juglansin seeds of walnut and butternut. 



Excelsin, " Brazil nut. 



Edestin, hemp seed. 



Avenalin, oats. 



Maysin, corn. 



Castanin, the seeds of European chestnut. 



Tuberin, potato tubers. 



And, crystalline globulins found in the seeds of flax, squash, castor- 

 bean, sesame, cotton, sunflower, radish, rape, mustard, and in cocoa- 

 nuts, candlenuts, and peanuts. 



1C. Glutelins 



Glutenin, found in the seeds of wheat. 

 Oryzenin, " " rice. 



ID. Prolamins 



Gliadin, found in the seeds of rye, wheat, with glutenin forms "gluten." 

 Hordein, " barley 



Zein, " " corn. 



1E-1G. Histories, Protamines and Albuminoids. So far as is 

 now known, no representatives of these classes are found in plants. 



2. Conjugated Proteins. There is no conclusive evidence of 

 the existence in plants of any of the conjugated proteins, other 



