THE CHEMISTRY OF THE ANIMAL BODY. 541 



Ba(OH) 2 . The two leucine may be separated by fermentation of cZ-leucin with PeniciUium 

 glaucum. Cleavage of proteid by acids and by putrefaction seems to yield cZ-leucin. 1 

 Cohn 2 states that several varieties of leucin arise in tryptic digestion. 



Caprylic, C 8 H 16 2 , and Capric, C 10 H 20 O 2 , Acids. — These are found as 

 glycerin esters in milk-fat. They are likewise present in sweat and in cheese. 



Palmitic, C 16 H 32 2 , and Stearic, C 18 H 36 2 , Acids. — As glycerin esters 

 these two acids are found in the ordinary fat of adipose tissue, and in the fat 

 of milk. The acids may occur in the feces, and are found combined with 

 calcium in adipocere (p. 560). Wool-fat consists of the cholesterin esters of 

 these acids. 



The bile contains palmitic, stearic, and oleic acids, 3 and to these have been 

 attributed its very slight acid reaction. 4 



Compounds of the Alcohol Radicals with Nitrogen. 



Amines. — These are bodies in which either one, two, or three of the hydrogen atoms 

 in ammonia are replaced by an alcohol radical, and are termed respectively primary, second- 

 ary, and tertiary amines. Methyl, ethyl, and propyl amine bases are the products of pro- 

 teid putrefaction. They resemble ammonia in their basic properties. 



Methylamine, NH 2 (CH 3 ). — This is found in herring-brine. It lias the fishy smell 

 noted in decaying fish. It is a product of the distillation of wood and of animal matter. 

 Feeding methylamine hydrochloride is said to cause the appearance of methylated urea in 

 a rabbit's urine 5 (analogous to the formation of urea from ammonia salts) : 

 2HC1.NH 2 (CH 3 ) + C0 2 = OC(NHCH 3 ) 2 + 2HC1 + H 2 0. 

 According to Sehiffer, 6 the body, probably through intestinal putrefaction, has the power 

 of partially converting creatin into oxalic acid, ammonia, carbonic acid, and methylamine, 

 which last is finally excreted as methylated urea in the urine. 



Ethylamine, C 2 H 5 NH 2 , when fed as carbonate appears in part as ethylated urea in the 

 urine. 7 



Trimethylamine, N(CH 3 ) 3 . — Like ethylamine, this is found in herring-brine and 

 among the products of proteid putrefaction and distillation. In the putrefaction of meat 

 the first ptomaine appearing is cholin, which certainly is derived from lecithin ; the cholin 

 (see p. 543) gradually disappears, and in its place trimethylamine may be detected. 8 



Compounds with Cyanogen. 



The radicle NC — forms a series of bodies not unlike the halogen com- 

 pounds. Owing to the mobility of the cyanogen group, Pfltiger 9 has sought 

 to attribute the properties of living proteid to its presence in ili«' molecule, 

 whereas in the dead proteid of the blood-plasma, for example, he imagines that 

 the nitrogen is contained in an amido- group. When the cyanogen radical 

 occurs in a compound in the form of N==C — the body is called a nitril, when 

 in the form of C=N — an iso-nitril. 



Cyanogen Gas, NC — CN. — A very poisonous gas. 



1 Gmelin: Zeitsehrift fiir physiologisehe Chemie, 1893, I'd. 18, 8.28. 



2 Ibid., 1895, Bd. 20, S. 203. 3 Lassar-Cohn : Ibid., 1891, Bd. 19, S. 571. 

 4 Jolles: Pfliiger's Archiv, 1894, Bd. 57, S. 13. 



* Sehin'er : ZeUsehrift fur physiologisehe Chemie, 1880, Bd. -1, S. 2 )■">. 6 L<>c cit. 



T Schmiedeberg : Archiv fiir exper. Pathologic and Pharmakologie, 1877, I'>d. 8, S. 5. 

 8 Brieger: Abstract in Jahresberichi iiber Thierehemie, L885, 8. 101. 

 s Pfliiger's Archiv, 1875, Bd. 10, S. 251. 



