THE n^OTRIDS Oil ALBUMINOIDS OF rill- OAT KERNEL.' 



liy Thomas 11. Osiiokne. 



I.— Historical. 



The proteids contained in or derived from the oat grain have been specially studied by J. P. 

 Norton, Baron vou Uibia, and Dr. W. Ka-eusler. Norton t recfigni/.ed three proteids, viz, (1) nllju- 

 min — 0.5-2.17 per cent — which was taken up from the "epidermis" (after starcii had been niechau- 

 ically removed by elutriatiou witli sli};htly aminoniacal water), by boiling with acetic acid, and 

 was precipitated by ucutraliziug the solution; (li) cajiein (or avenine, as Johnson, in wh(»se labora- 

 tory the work was done, named it) — 15.70-17.72 per cent — which was dissolved in the slightly aiu- 

 mouiacal water used iu separating starch, and thrown down by acetic acid; (.?) (/liiiin — 1..J3-2.47 

 per cent — extracted by alcohol and separated from oil by means of ether, and from sugar by water. 



Yon Bibraf found that no coherent gluten could be got from oat flour by kneading iu water. 

 He recogiuzed albumin — 1.24-1.52 per cent — precipitated by boiling the cold-water extract of the 

 ground oats; caxcin — 0.15-0.17 per cent — the body separating from the hot alcohol extract mi 

 cooling; pUiitt ijclatin (Dumas' (jlntin, Tad(b'i's (jliadin) — 3.00-.5.25 per cent — the sul)stan(e soluble 

 both iu hot and cold alcohol; and nitrogenous substance insolulile in water and aleohol — 11.38-14.85 

 per cent. 



Kreusler§ found oat gliadin, soluble in weak alcohol and oat legumin, .-soluble iu very dilute 

 alkali. 



Since the date of Kreusler's work, 186'J, our knowledge of proteid bodies and of the methods 

 for their investigation has been considerably extended. This advance has been chiefly iu the study 

 ol' the animal proteids, but little real progress having been made in our knowledge of the vegeta- 

 ble albuminoids. The following i-esearch was undertaken with a view to applying the newer 

 methods of study to the plant jiroteids that have agricultural importance. 



II. — Oat Proteids Extuacted by Weak Alcohol. 



(«) kreusler's work. 



The oat proteid soluble in weak alcohol was first examined, and, as results diftering from Kreus- 

 ler's were obtained, it will be well to give here a brief summary of his work. 



Kreusler found that, on extractinggrouud oats with alcohol of 80 per cent and concentrating the 

 extract to ouethii-d of its volume, a considerable amount of sub.stance separated which, after sub- 

 siding from the solution, became a tough, transparent uuiss of amber-yellow color. The solution 

 decanted from this substance and further concentrated yielded a .second deposit. The liquid 

 poured from this .second deposit yielded, on still further concentration, a third. The three sedi- 

 ments were united and dissolved in 80 per cent alcohol at a gentle heat. On cooling, the greater 

 part of the substance precii)itated. After decanting the liquid, this precipitate was treated with 

 absolute alcohol, which caused it to gather on the walls of the vessel as a tenacious mass. After 

 treating with ether and again with absolute alcohol, it was drieil over sulphuric acid. This Kreus- 

 ler desiguated "A." 



" Presented to the Xational Academy of Sciences, in Boston, November 13, 1890, and New York, November 10, 1891. 



t Am. .1. Sci. [2] 3. 330 (1815); 5, 22 (18.«8). 



t Die Getreidearten iiud das Brod (NUmberg, IStt)). 



M- prakt. Chom. 107, 17. 51 



