'^"'■Feb.'i'ifss^'"™'}  Bitter  Principle  of  Burdock  Fruit  79 
Dilute  soda  extract  : 
Albuminoids  and  mucilage,  8.00  per  cent. 
Lignin,  3.82  " 
Intercellular  substances,  21.86  " 
Cellulose,  9.31 
Ash,  (silica)  0.59 
Loss,  2.95 
100.00 
THE  BITTER  PRINCIPLE  OF  BURDOCK  FRUIT. 
Contribution  from  the  Chemical  Laboratory  of  the  Philadelphia  College  of 
Pharmacy. 
By  Heney  Trimble, 
In  the  American  Journal  of  Pharmacy  for  1885^  page  127, 
is  an  account  of  the  proximate  analysis  of  burdock  fruit,  by  Mr.  J.  D. 
MacFarland  and  myself,  in  which  it  was  stated  that  the  bitter  prin- 
ciple, then  believed  to  be  an  alkaloid,  would  be  further  investigated. 
Since  then  as  time  has  permitted  I  have  reviewed  the  work  until  an 
entire  re-analysis  has  been  completed.  The  results  differ  in  no  import- 
ant particular  from  those  recorded  then,  except  in  the  character  of  the 
bitter  principle. 
The  absolute  alcohol  extract  has  been  found  now  as  then,  to  consist 
of  a  little  resinous  substance,  somewhat  soluble  in  water,  and  com- 
pletely soluble  in  dilute  alcohol.  A  large  quantity  of  the  desired 
material  was  prepared  by  exhausting  the  drug  with  petroleum  spirit 
to  remove  fixed  oil,  and  then  with  alcohol.  On  pouring  the  concen- 
trated alcoholic  solution  into  water  the  resin  separated,  but  the  bitter 
principle  dissolved  in  the  water,  from  which  it  was  readily  removed  by 
agitation  with  chloroform.  The  residue  on  evaporating  the  chloroform 
was  treated  with  water,  and  the  clear  aqueous  solution  allowed  to  evapo- 
rate in  a  desiccator  over  sulphuric  acid,  when  a  white  granular  crystal- 
line substance  separated.  This  may  be  further  purified  by  resolution 
in  water  and  again  evaporating  in  a  desiccator.  The  purified  material 
is  pure  white,  of  an  intensely  bitter  taste,  and  has  a  neutral  reaction. 
On  testing  for  alkaloids,  negative  results  are  gotten.  Fehling's  solu- 
tion is  not  reduced,  but  on  first  boiling  with  very  dilute  hydrochloric 
acid  for  fifteen  minutes  the  solution  becomes  cloudy,  and  finally  a  resin 
separates  which  appears  to  be  identical  with  the  resin  obtained  on 
pouring  the  alcoholic  solution  into  water  ;  now  when  the  clear  filtrate 
