Am,juiUyr;i893aruJ'}      Chemical  Constitution  of  Peptones.  361 
cent.) ;  then  proto-albumose  (loss  28-3  per  cent).  Peptone  loses  5  1 
to  51-8  per  cent. 
Koch's  tuberculin  contains  an  indole-like  substance  in  addition  to 
albumoses  (small  quantities  of  proto-albumose,  large  quantities  of 
deutero-albumose).  In  the  process  of  the  action  of  the  tubercle, 
bacillus,  proto-albumose  is  first  formed,  then  deutero-albumose. 
The  bacteria  so  far  act  like  digestive  ferments,  but  there  is  little  or 
no  true  peptone  formed  ;  and  leucine  and  tyrosine  are  also  absent. 
Tuberculin  also  gives  a  color  with  bromine ;  this  substance,  trypto- 
phan, or  proteinchromogen,  is  probably  a  mixture  of  the  indole-like 
substance  with  other  not  fully  recognized  materials. 
The  hay  bacillus  acts  somewhat  differently  when  grown  in  solutions 
of  proto-albumose,  for  not  only  are  secondary  albumoses  formed, 
but  also  true  peptone,  tyrosine,  leucine,  tryptophan  and  ammonia. 
It  is  thus  very  like  trypsin  in  its  action. 
With  Bacillus  prodigiosus  very  little  albumose  remains ;  it  is  almost 
entirely  broken  up  into  peptone,  leucine,  tyrosine,  tryptophan,  and 
the  indole-yielding  substance. 
In  no  case  was  there  any  formation  of  hydrogen  sulphide. 
CHEMICAL  CONSTITUTION  OF  PEPTONES.1 
By  P.  Schutzenberger. 
Fibrin  peptone,  obtained  from  the  blood  of  the  horse  in  the  manner 
previously  described,  is  evidently  not  homogeneous.  If  a  somewhat 
syrupy  solution  obtained  by  concentration  on  a  water-bath  is  mixed 
with  gradually  increasing  quantities  of  strong  alcohol,  precipitates 
are  obtained  which  are  more  and  more  soluble  in  alcohol.  About 
one-fifth  of  the  fibrin  peptone  remains  in  solution,  even  when  the 
liquid  contains  from  85  to  90  per  cent,  of  alcohol.  The  composition 
of  the  various  fractions  is  not'  identical,  but  indicates  that  they  are 
probably  different  terms  in  a  homologous  series.  The  first  precipi- 
tate has  the  composition  C29H51N8013,  whilst  the  mean  composition 
of  all  the  fractions  is  C31H55N8013.  The  portion  soluble  in  alcohol 
has  the  composition  C30H56N8O13.  The  various  fractions,  when 
heated  for  four  or  five  hours  at  1800  with  3  parts  of  barium  hydrox- 
ide, all  behave  like  fibrin  peptone  and  yield  ammonia,  carbonic 
anhydride,  acetic  acid,  and  a  non-volatile  residue  consisting  of  a 
1  Compt.  rend.,  115,  764-768  ;  Jour.  Chem.  Soc,  Abst.  I,  235. 
