THE  AMERICAN 
JOURNAL  OF  PHARMACY. 
MARCH,  1889. 
ASCLEPIAS  CORNUTI  AND  ASCLEPIAS  TUBEROSA. 
By  Feed.  B.  Quackenbush. 
Read  at  the  Pharmaceutical  Meeting,  February  19. 
An  analysis  of  Asclepias  tuberosa  was  made  in  1861  by  Elaro 
Rhoads,1  who  announced  the  presence  of  a  peculiar  principle  possess- 
ing the  taste  of  the  root  which  he  obtained  from  a  concentrated  infu- 
sion of  the  drug  by  precipitation  with  tannic  acid. 
In  18S1,  W.  L.  Hinchman2  observed  in  Asclepias  Cornuti  a  crystal- 
line principle,  but  obtained  it  in  a  different  manner.  He  treated  the 
drug  with  petroleum  ether,  evaporated  spontaneously  and  treated  the 
residue  with  95  per  cent,  alcohol  from  which  yellow  wart-like  crystals 
were  deposited  which  after  purification  were  white.  List,  in  1849, 
also  separated  a  crystalline  principle  from  the  milk  juice  by  exhaust- 
ing the  congealed  juice  with  ether.  . 
The  Asclepias  Cornuti  used  in  the  following  analysis  was  collected 
and  carefully  dried  by  Prof.  Henry  Trimble  during  the  summer  of 
1888. 
A  complete  analysis  of  the  Ascelepias  tuberosa  was  not  made,  but  it 
was  examined  for  the  purpose  of  learning  if  the  crystalline  principle 
which  was  found  in  the  Asclepias  Cornuti  also  existed  in  it. 
Fifty  grams  of  the  powdered,  root  were  macerated  with  petroleum 
ether  in  several  portions.  This  solution  showed  a  distinct  fluorescence 
similar  to  that  observed  in  petrolatum,  and  yielded  on  evaporation  1#44 
per  cent,  of  a  peculiar  residue  supposed  to  consist  of  caoutchouc,  resin 
and  volatile  oil  to  the  extent  of  2  per  cent.    This  residue  was  insol- 
1  Amer.  Jour.  Phar.,  1861,  p.  493. 
2  Amer.  Jour.  Phar.,  1881,  p.  433. 
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