24 
Extracts  of  Licorice. 
f  Am.  Jour.  Pharm. 
\    January,  1898. 
During  the  course  of  these  experiments,  it  was  found  that  the 
method  in  which  the  ammoniacal  water  is  used  was  not  practical 
on  account  of  the  starchy  materials  present  closing  up  the  pores  of 
the  filter  so  the  liquid  could  not  pass  through  it.  More  success  was 
had  from  the  solvent  containing  alcohol,  as  the  alcohol  seemed  to 
coagulate  the  starch  to  a  sufficient  extent  to  make  it  possible  to 
filter  off  the  insoluble  part  of  the  extract;  but  even  under  these 
conditions  it  required  about  twenty  hours  to  effect  filtration.  An 
attempt  was  made  to  shorten  the  time  required  by  using  a  suction 
pump,  but  this  was  found  to  be  impracticable,  on  account  of  the 
filter  clogging. 
The  following  solvent  for  the  extraction  of  the  glycyrrhizin  was 
found  to  give  the  most  satisfactory  results  : 
Moisture. — A  weighed  quantity  (about  I  gramme)  of  the  extract 
was  put  in  a  porcelain  crucible,  and  dried  in  an  air  bath  at  a  tem- 
perature between  ioo°  and  no0  C.  The  loss  in  weight  was  taken 
as  the  amouut  of  moisture  present. 
Ash. — The  residue  remaining  after  treating  as  above  was  ignited 
to  low  redness  over  a  Bunsen  burner,  until,  on  prolonged  ignition, 
the  weight  remained  constant.  The  residue  gave  the  inorganic 
matter  in  the  extract. 
Insoluble  Matter. — One  gramme  of  the  extract  was  carefully 
weighed,  and  treated  in  a  beaker  with  25  c.c.  of  the  solvent  previ- 
ously mentioned.  The  mixture  was  stirred  at  close  intervals  during 
an  hour,  and  then  allowed  to  stand  for  about  twelve  hours,  so  that 
the  insoluble  matter  could  settle  out.  The  supernatant  liquid  was 
decanted  upon  balanced  filters,  the  residue  in  the  beaker  treated 
with  5  c.c.  more  of  the  solvent,  allowed  to  settle  again,  decanted  as 
before,  and  the  insoluble  matter  transferred  to  the  filter  and  washed 
until  the  washings  passed  through  colorless.  The  filters  and  residue 
were  then  placed  in  an  air-bath  and  dried  at  ioo°-i  io°  C. 
Glycyrrhizin. — The  filtrate  from  the  above  was  acidified  with 
dilute  sulphuric  acid,  which  precipitated  the  glycyrrhizin  as  a  dark 
brown  scale,  which  coagulated  on  standing.    The  precipitate  was 
c.c. 
Official  Ammonia  Water  .... 
Official  Alcohol  
Sufficient  Water  to  make  a  litre. 
40 
240 
METHOD  OF  ANALYSIS. 
