iv THE CARBOHYDRATE RADICALS 161 



50 to 80 per cent of the latter. Animal gum is not a uniform body but 

 a mixture of the suspected polysaccharid with more or less of mucin- 

 albumoses and perhaps also albuminates. Leo Langstein 1 believes^ 

 however, in the existence of a true animal gum. 



On dissociating pseudo-mucins by strong mineral acids, Otori 2 has 

 obtained laevulinic acid, showing the presence of a true carbohydrate 

 radical in pseudo-mucin. Paramucin does not give rise to laevulinic 

 acid according to Panzer. 3 



The percentage composition of animal gum is interesting, as, 

 according to "Weydemann it contains only 4 to 5 per cent of nitrogen, 

 which means that some portion of the animal gum must contain less 

 nitrogen than does glucosamin. As the carbon percentage is also low, 

 the simplest assumption to make is that animal gum is an aminated 

 polysaccharid. This conclusion has been arrived at by Schulz and 

 Ditthorn ; 4 as the glucoproteid contains hardly more nitrogen than does 

 the galactosamin which is prepared from it, there must be present 

 either another non-nitrogenous body, or the NH 2 -group of the galacto- 

 samin must be linked in some other manner to the proteid moiety. It 

 is, of course, possible that individual mucins may be quite different in 

 this respect (Cohnheim.) 



No definite statements can be made as to the amount of glucosamin 

 present in an albumin-molecule, as it is so readily destroyed. The highest 

 values attained so far are 36*9 per cent for the mucin from the trachea 

 (Miiller) ; 34*9 per cent for ovomucoid (Seemann) ; 30 per cent for the 

 pseudomucin of ovarial cysts (Zangerle). For pseudomucin much 

 lower values have been obtained, namely, 12 '5 per cent by Mitjukoff; 

 10 per cent by Steudel, 2 per cent by Pfannenstiel ; we are therefore 

 dealing in all probability with different bodies (Neuberg and Heymann). 

 Schulz and Ditthorn 4 found in the mucin of frog's spawn a large 

 amount of galactosamin, as already mentioned. 



Egg-albumin behaves exactly as do the mucins. After osazones 

 and reducing substances had repeatedly been prepared from it, 

 Seemann and Langstein 5 succeeded in obtaining glucosamin from it, 

 Seemann obtained 8 '5 grammes glucosamin from 100 grammes 

 albumin ; Hof meister 6 obtained even 1 5 per cent. 



Now the question arises : Shall we put the mucins and allied 



1 Langstein, Ergebnisse d. Physiol. 3. Part 1, p. 453 (1904) ; and in Zeitschr. /. 

 physiol. Chem. 42. 171 (1904). 



2 J. Otori, Zeitschr. f. physiol. Chem. 42. 453, 43. 74 and 86. 



3 Panzer, ibid. 28. 363 (1899). 



4 F. N. Schulz and F. Ditthorn, ibid. 32. 428 (1901). 



5 L. Langstein, ibid. 31. 49 (1900). 



6 F. Hoffmeister, ibid. 24. 159 [p. 170] (1899) ; D. Kurajeff, ibid. 26. 462 (1899). 



M 



