476  Glycyrrhizin  in  Licorice  Root.        1  Amjui°y  ri^i arm* 
The  Quantitative  Testing  of  the  Published  Methods, 
i.  tschirch-erikson  (1910). 
The  method  given  by  Tschirch-Erikson  for  the  simultaneous  de- 
termination of  glycyrrhizin  and. of  sugars  in  licorice  root,  is  funda- 
mentally the  same  as  that  already  mentioned  for  licorice  extract.  In 
carrying  it  out  practically,  however,  there  are  some  differences.  In 
addition  to  the  actual  method  for  licorice  root,  I  wish  to  discuss  at 
this  place  the  experiments  which  Erikson  used,  from  which  to  estab- 
lish her  analytical  procedure.  The  basic  thought  of  the  method  pro- 
posed by  Tschirsch,  I  have  already  discussed  under  the  methods  for 
licorice  extract,  so  that  I  can  assume  at  this  point  that  it  is  known. 
The  procedure  for  examining  licorice  root  according  to  Erik- 
son  is  as  follows : 
"I.  First  the  glucose  is  determined  by  15  hours  standing  with 
Fehling  solution  in  the  cold. 
"II.  After  filtering  off  the  precipitated  cuprous  oxide,  the  sac- 
charose is  determined  by  short  boiling  with  Fehling  solution,  and 
finally, 
"III.  The  glucuronic  acid  split  off  from  the  glycyrrhizin  is  de- 
termined in  the  filtrate  by  long  boiling  with  Fehling  solution." 
This  differs  from  the  method  proposed  for  licorice  extract.  In 
the  latter  case,  the  glycyrrhizin  is  first  separated  with  sulphuric  acid, 
and  the  filtrate,  containing  the  sugars,  is  treated  separately.  In  the 
case  of  the  root,  the  order  is  changed,  first  the  glucose,  then  saccha- 
rose, and  finally  the  glycyrrhizic  acid  being  determined.  The  reason 
for  this  change  is  not  clear.  Erikson  says  that  "The  method  has  been 
changed  by  conditions  imposed  by  the  material."  She  does  not  state 
what  grounds  lead  to  this  change. 
Her  research  is  divided  into  four  sections : 
1.  Preparation  of  the  root  extract. 
2.  Determination  of  glucose. 
3.  Determination  of  glucoses  present  as  saccharose. 
4.  Determination  of  the  glycyrrhizic  acid. 
1.  Preparation  of  the  Extract. 
On  the  basis  of  three  experimental  series,  Erikson  proposed  the 
following  method  for  the  preparation  of  the  extract  of  the  root. 
"Ten  g.  of  powdered  licorice  root  are  mixed  with  an  equal  vol- 
ume of  powdered  glass,  moistened  with  a  little  water,  and  allowed  to 
