Am.  Jour.  Pharm. 
July,  1921. 
Studies  on  Licorice  Root. 
489 
Moreover,  the  "direct"  glycyrrhizins  were  only  slightly  less  pure 
than  the  others,  judging  by  color  and  taste.  Here,  again,  it  seems  to 
be  a  question  of  the  physical  condition  of  the  glycyrrhizin, — that 
which  is  obtained  from  root  previously  treated  with  absolute  alcohol 
is  subject  to  greater  loss  in  washing  than  that  not  so  treated. 
This  is  easily  shown  as  follows : 
The  glycyrrhizin  method  which  I  have  given  for  licorice  extract 
prescribes  two  precipitations  with  sulphuric  acid — the  first  giving  the 
main  portion,  and  the  second  giving  a  supplementary  portion  from 
the  evaporated  filtrate  and  washings  from  the  first.  When,  now,  this 
procedure  is  carried  out  with  root  on  which  no  preliminary  treat- 
ment with  strong  alcohol  is  given,  the  second  portion  is  very  small 
(the  first  main  portion  will  be,  say,  10  per  cent.,  and  the  second 
usually  0.3-0.6  per  cent.).  When,  however,  the  analytical  process  is 
applied  to  root  which  has  been  treated  previously  with  strong  alcohol, 
the  washings  from  the  main  glycyrrhizin  precipitate  are  very  notice- 
ably of  darker  color,  giving  a  much  larger  second  precipitate,  and 
even  the  filtrate  and  washings  from  the  second  portion  sometimes 
contain  a  considerable  amount  of  glycyrrhizin.  The  first  portion 
frequently  drops  to,  say  5  per  cent,  and  the  second  portion  may  be  as 
much  as  2  per  cent.,  a  clear  indication  of  the  reason  for  low  results, 
viz.,  that  glycyrrhizin  has  in  this  case  been  lost  in  the  washing.  The 
low  results  are  not  due,  essentially,  to  removal  of  glycyrrhizin  by 
the  strong  alcohol,  and  the  high  results  in  the  "direct"  method  are  not 
essentially  due  to  contamination  of  the  glycyrrhizin  with  resins  and 
bitter  substances. 
There  is  no  advantage  in  adding  a  little  ammonia  to  the  absolute 
alcohol.  It  renders  the  extraction  of  resins  and  bitter  substances 
less  sharp,  and  gives  slightly  lower  glycyrrhizin  figures. 
The  conclusions  drawn  from  the  table  above  were  confirmed  by 
repetition.    In  fact  the  discrepancies  were  even  more  marked. 
Spanish.  Greek..  Russian.  Anatolian. 
Hot  Abs.  Alcohol  Extract                      11.2  8.4  10.4  8.3 
Glycyrrhizin  in  residual  root  (based 
on  original  root)                                5.8  7.4  8.9  9.8 
"Direct"  glycyrrhizhin                           11.1  10.4  14. 1  14.7 
It  was  easy  to  notice  in  carrying  out  this  series,  how  a  consider- 
able part  of  the  glycyrrhizin  from  roots  previously  treated  with  hot 
