16 PHYSIOLOGICAL CHEMISTRY. 



weight of the albumins has not been determined, therefore it is 

 impossible to give formulae. For the alkali albuminate, in whose 

 formation from native albumins a part of the nitrogen and the 

 loosely-bound sulphur is split off, LIEBERKUHN has given the 

 formula C tl H 11Q N 18 SO M . 



The constitution of the albuminous bodies, notwithstanding 

 numerous investigations, is still unknown. By heating albumin 

 with barium hydrate and water in sealed tubes at 150-200 C. for 

 several days, SCHUTZENBERGER obtained a number of products 

 among which were ammonia, carbon dioxide, oxalic acid, acetic 

 acid, and, as chief product, a mixture of amido-acids. This mix- 

 ture contained, besides a little tyrosin and a few other bodies, 

 chiefly acids of the series C n H 3n+1 N0 2 (leucines) and C n H 2n _iNO a 

 (leuceines). The sulphur of the albumins yields sulphites. The 

 three bodies, carbon dioxide, oxalic acid, and ammonia, are formed 

 in the same relative proportion as in the decomposition of urea 

 and oxamid; therefore 'SCHUTZENBERGER suggests that perhaps 

 albumin may be considered as a very complex ureid or oxamid. 

 Such a conclusion cannot be derived from the above decomposition 

 processes for several reasons, and the attempts to prepare urea 

 directly by splitting albumin by means of trypsin, or by oxidation, 

 have given negative, or at least not positive, results. 



On fusing albumin with caustic alkali, ammonia and other 

 volatile products are generated; among these leucin, from which 

 volatile fatty acids, such as acetic acid, valerianic acid, and also 

 butyric acid, are formed; also tyrosin, from which phenol, indol, 

 and skatol are produced. The majority of these products are 

 found as a result of putrefaction (see Chap. VII). On boiling 

 with mineral acids, or still better by boiling with hydrochloric 

 acid and zinc chloride (HLASIWETZ and HABERMANIJ), the albumins 

 yields amido-acids, such as leucin, aspartic acid, glutamic acid, and 

 tyrosin (and from vegetable albumin SCHULZE and BARBIERI ob- 

 tained tf-phenylamido-propionic acid), also sulphuretted hydrogen, 

 ammonia, and nitrogenized bases (DRECHSEL). As an essential 

 difference between the action of acids and alkalies (barium hydrate) 

 on albumins, DRECHSEL suggests that by the action of acids car- 

 bon dioxide, oxalic and acetic acids are not produced. 



By the putrefaction of albumins, as well as by decomposition 



